src/platform/libretro/libretro.h (view raw)
1/* Copyright (C) 2010-2020 The RetroArch team
2 *
3 * ---------------------------------------------------------------------------------------
4 * The following license statement only applies to this libretro API header (libretro.h).
5 * ---------------------------------------------------------------------------------------
6 *
7 * Permission is hereby granted, free of charge,
8 * to any person obtaining a copy of this software and associated documentation files (the "Software"),
9 * to deal in the Software without restriction, including without limitation the rights to
10 * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software,
11 * and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
12 *
13 * The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
14 *
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
16 * INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
18 * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
19 * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
20 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
21 */
22
23#ifndef LIBRETRO_H__
24#define LIBRETRO_H__
25
26#include <stdint.h>
27#include <stddef.h>
28#include <limits.h>
29
30#ifdef __cplusplus
31extern "C" {
32#endif
33
34#ifndef __cplusplus
35#if defined(_MSC_VER) && _MSC_VER < 1800 && !defined(SN_TARGET_PS3)
36/* Hack applied for MSVC when compiling in C89 mode
37 * as it isn't C99-compliant. */
38#define bool unsigned char
39#define true 1
40#define false 0
41#else
42#include <stdbool.h>
43#endif
44#endif
45
46#ifndef RETRO_CALLCONV
47# if defined(__GNUC__) && defined(__i386__) && !defined(__x86_64__)
48# define RETRO_CALLCONV __attribute__((cdecl))
49# elif defined(_MSC_VER) && defined(_M_X86) && !defined(_M_X64)
50# define RETRO_CALLCONV __cdecl
51# else
52# define RETRO_CALLCONV /* all other platforms only have one calling convention each */
53# endif
54#endif
55
56#ifndef RETRO_API
57# if defined(_WIN32) || defined(__CYGWIN__) || defined(__MINGW32__)
58# ifdef RETRO_IMPORT_SYMBOLS
59# ifdef __GNUC__
60# define RETRO_API RETRO_CALLCONV __attribute__((__dllimport__))
61# else
62# define RETRO_API RETRO_CALLCONV __declspec(dllimport)
63# endif
64# else
65# ifdef __GNUC__
66# define RETRO_API RETRO_CALLCONV __attribute__((__dllexport__))
67# else
68# define RETRO_API RETRO_CALLCONV __declspec(dllexport)
69# endif
70# endif
71# else
72# if defined(__GNUC__) && __GNUC__ >= 4 && !defined(__CELLOS_LV2__)
73# define RETRO_API RETRO_CALLCONV __attribute__((__visibility__("default")))
74# else
75# define RETRO_API RETRO_CALLCONV
76# endif
77# endif
78#endif
79
80/* Used for checking API/ABI mismatches that can break libretro
81 * implementations.
82 * It is not incremented for compatible changes to the API.
83 */
84#define RETRO_API_VERSION 1
85
86/*
87 * Libretro's fundamental device abstractions.
88 *
89 * Libretro's input system consists of some standardized device types,
90 * such as a joypad (with/without analog), mouse, keyboard, lightgun
91 * and a pointer.
92 *
93 * The functionality of these devices are fixed, and individual cores
94 * map their own concept of a controller to libretro's abstractions.
95 * This makes it possible for frontends to map the abstract types to a
96 * real input device, and not having to worry about binding input
97 * correctly to arbitrary controller layouts.
98 */
99
100#define RETRO_DEVICE_TYPE_SHIFT 8
101#define RETRO_DEVICE_MASK ((1 << RETRO_DEVICE_TYPE_SHIFT) - 1)
102#define RETRO_DEVICE_SUBCLASS(base, id) (((id + 1) << RETRO_DEVICE_TYPE_SHIFT) | base)
103
104/* Input disabled. */
105#define RETRO_DEVICE_NONE 0
106
107/* The JOYPAD is called RetroPad. It is essentially a Super Nintendo
108 * controller, but with additional L2/R2/L3/R3 buttons, similar to a
109 * PS1 DualShock. */
110#define RETRO_DEVICE_JOYPAD 1
111
112/* The mouse is a simple mouse, similar to Super Nintendo's mouse.
113 * X and Y coordinates are reported relatively to last poll (poll callback).
114 * It is up to the libretro implementation to keep track of where the mouse
115 * pointer is supposed to be on the screen.
116 * The frontend must make sure not to interfere with its own hardware
117 * mouse pointer.
118 */
119#define RETRO_DEVICE_MOUSE 2
120
121/* KEYBOARD device lets one poll for raw key pressed.
122 * It is poll based, so input callback will return with the current
123 * pressed state.
124 * For event/text based keyboard input, see
125 * RETRO_ENVIRONMENT_SET_KEYBOARD_CALLBACK.
126 */
127#define RETRO_DEVICE_KEYBOARD 3
128
129/* LIGHTGUN device is similar to Guncon-2 for PlayStation 2.
130 * It reports X/Y coordinates in screen space (similar to the pointer)
131 * in the range [-0x8000, 0x7fff] in both axes, with zero being center and
132 * -0x8000 being out of bounds.
133 * As well as reporting on/off screen state. It features a trigger,
134 * start/select buttons, auxiliary action buttons and a
135 * directional pad. A forced off-screen shot can be requested for
136 * auto-reloading function in some games.
137 */
138#define RETRO_DEVICE_LIGHTGUN 4
139
140/* The ANALOG device is an extension to JOYPAD (RetroPad).
141 * Similar to DualShock2 it adds two analog sticks and all buttons can
142 * be analog. This is treated as a separate device type as it returns
143 * axis values in the full analog range of [-0x7fff, 0x7fff],
144 * although some devices may return -0x8000.
145 * Positive X axis is right. Positive Y axis is down.
146 * Buttons are returned in the range [0, 0x7fff].
147 * Only use ANALOG type when polling for analog values.
148 */
149#define RETRO_DEVICE_ANALOG 5
150
151/* Abstracts the concept of a pointing mechanism, e.g. touch.
152 * This allows libretro to query in absolute coordinates where on the
153 * screen a mouse (or something similar) is being placed.
154 * For a touch centric device, coordinates reported are the coordinates
155 * of the press.
156 *
157 * Coordinates in X and Y are reported as:
158 * [-0x7fff, 0x7fff]: -0x7fff corresponds to the far left/top of the screen,
159 * and 0x7fff corresponds to the far right/bottom of the screen.
160 * The "screen" is here defined as area that is passed to the frontend and
161 * later displayed on the monitor.
162 *
163 * The frontend is free to scale/resize this screen as it sees fit, however,
164 * (X, Y) = (-0x7fff, -0x7fff) will correspond to the top-left pixel of the
165 * game image, etc.
166 *
167 * To check if the pointer coordinates are valid (e.g. a touch display
168 * actually being touched), PRESSED returns 1 or 0.
169 *
170 * If using a mouse on a desktop, PRESSED will usually correspond to the
171 * left mouse button, but this is a frontend decision.
172 * PRESSED will only return 1 if the pointer is inside the game screen.
173 *
174 * For multi-touch, the index variable can be used to successively query
175 * more presses.
176 * If index = 0 returns true for _PRESSED, coordinates can be extracted
177 * with _X, _Y for index = 0. One can then query _PRESSED, _X, _Y with
178 * index = 1, and so on.
179 * Eventually _PRESSED will return false for an index. No further presses
180 * are registered at this point. */
181#define RETRO_DEVICE_POINTER 6
182
183/* Buttons for the RetroPad (JOYPAD).
184 * The placement of these is equivalent to placements on the
185 * Super Nintendo controller.
186 * L2/R2/L3/R3 buttons correspond to the PS1 DualShock.
187 * Also used as id values for RETRO_DEVICE_INDEX_ANALOG_BUTTON */
188#define RETRO_DEVICE_ID_JOYPAD_B 0
189#define RETRO_DEVICE_ID_JOYPAD_Y 1
190#define RETRO_DEVICE_ID_JOYPAD_SELECT 2
191#define RETRO_DEVICE_ID_JOYPAD_START 3
192#define RETRO_DEVICE_ID_JOYPAD_UP 4
193#define RETRO_DEVICE_ID_JOYPAD_DOWN 5
194#define RETRO_DEVICE_ID_JOYPAD_LEFT 6
195#define RETRO_DEVICE_ID_JOYPAD_RIGHT 7
196#define RETRO_DEVICE_ID_JOYPAD_A 8
197#define RETRO_DEVICE_ID_JOYPAD_X 9
198#define RETRO_DEVICE_ID_JOYPAD_L 10
199#define RETRO_DEVICE_ID_JOYPAD_R 11
200#define RETRO_DEVICE_ID_JOYPAD_L2 12
201#define RETRO_DEVICE_ID_JOYPAD_R2 13
202#define RETRO_DEVICE_ID_JOYPAD_L3 14
203#define RETRO_DEVICE_ID_JOYPAD_R3 15
204
205#define RETRO_DEVICE_ID_JOYPAD_MASK 256
206
207/* Index / Id values for ANALOG device. */
208#define RETRO_DEVICE_INDEX_ANALOG_LEFT 0
209#define RETRO_DEVICE_INDEX_ANALOG_RIGHT 1
210#define RETRO_DEVICE_INDEX_ANALOG_BUTTON 2
211#define RETRO_DEVICE_ID_ANALOG_X 0
212#define RETRO_DEVICE_ID_ANALOG_Y 1
213
214/* Id values for MOUSE. */
215#define RETRO_DEVICE_ID_MOUSE_X 0
216#define RETRO_DEVICE_ID_MOUSE_Y 1
217#define RETRO_DEVICE_ID_MOUSE_LEFT 2
218#define RETRO_DEVICE_ID_MOUSE_RIGHT 3
219#define RETRO_DEVICE_ID_MOUSE_WHEELUP 4
220#define RETRO_DEVICE_ID_MOUSE_WHEELDOWN 5
221#define RETRO_DEVICE_ID_MOUSE_MIDDLE 6
222#define RETRO_DEVICE_ID_MOUSE_HORIZ_WHEELUP 7
223#define RETRO_DEVICE_ID_MOUSE_HORIZ_WHEELDOWN 8
224#define RETRO_DEVICE_ID_MOUSE_BUTTON_4 9
225#define RETRO_DEVICE_ID_MOUSE_BUTTON_5 10
226
227/* Id values for LIGHTGUN. */
228#define RETRO_DEVICE_ID_LIGHTGUN_SCREEN_X 13 /*Absolute Position*/
229#define RETRO_DEVICE_ID_LIGHTGUN_SCREEN_Y 14 /*Absolute*/
230#define RETRO_DEVICE_ID_LIGHTGUN_IS_OFFSCREEN 15 /*Status Check*/
231#define RETRO_DEVICE_ID_LIGHTGUN_TRIGGER 2
232#define RETRO_DEVICE_ID_LIGHTGUN_RELOAD 16 /*Forced off-screen shot*/
233#define RETRO_DEVICE_ID_LIGHTGUN_AUX_A 3
234#define RETRO_DEVICE_ID_LIGHTGUN_AUX_B 4
235#define RETRO_DEVICE_ID_LIGHTGUN_START 6
236#define RETRO_DEVICE_ID_LIGHTGUN_SELECT 7
237#define RETRO_DEVICE_ID_LIGHTGUN_AUX_C 8
238#define RETRO_DEVICE_ID_LIGHTGUN_DPAD_UP 9
239#define RETRO_DEVICE_ID_LIGHTGUN_DPAD_DOWN 10
240#define RETRO_DEVICE_ID_LIGHTGUN_DPAD_LEFT 11
241#define RETRO_DEVICE_ID_LIGHTGUN_DPAD_RIGHT 12
242/* deprecated */
243#define RETRO_DEVICE_ID_LIGHTGUN_X 0 /*Relative Position*/
244#define RETRO_DEVICE_ID_LIGHTGUN_Y 1 /*Relative*/
245#define RETRO_DEVICE_ID_LIGHTGUN_CURSOR 3 /*Use Aux:A*/
246#define RETRO_DEVICE_ID_LIGHTGUN_TURBO 4 /*Use Aux:B*/
247#define RETRO_DEVICE_ID_LIGHTGUN_PAUSE 5 /*Use Start*/
248
249/* Id values for POINTER. */
250#define RETRO_DEVICE_ID_POINTER_X 0
251#define RETRO_DEVICE_ID_POINTER_Y 1
252#define RETRO_DEVICE_ID_POINTER_PRESSED 2
253#define RETRO_DEVICE_ID_POINTER_COUNT 3
254
255/* Returned from retro_get_region(). */
256#define RETRO_REGION_NTSC 0
257#define RETRO_REGION_PAL 1
258
259/* Id values for LANGUAGE */
260enum retro_language
261{
262 RETRO_LANGUAGE_ENGLISH = 0,
263 RETRO_LANGUAGE_JAPANESE = 1,
264 RETRO_LANGUAGE_FRENCH = 2,
265 RETRO_LANGUAGE_SPANISH = 3,
266 RETRO_LANGUAGE_GERMAN = 4,
267 RETRO_LANGUAGE_ITALIAN = 5,
268 RETRO_LANGUAGE_DUTCH = 6,
269 RETRO_LANGUAGE_PORTUGUESE_BRAZIL = 7,
270 RETRO_LANGUAGE_PORTUGUESE_PORTUGAL = 8,
271 RETRO_LANGUAGE_RUSSIAN = 9,
272 RETRO_LANGUAGE_KOREAN = 10,
273 RETRO_LANGUAGE_CHINESE_TRADITIONAL = 11,
274 RETRO_LANGUAGE_CHINESE_SIMPLIFIED = 12,
275 RETRO_LANGUAGE_ESPERANTO = 13,
276 RETRO_LANGUAGE_POLISH = 14,
277 RETRO_LANGUAGE_VIETNAMESE = 15,
278 RETRO_LANGUAGE_ARABIC = 16,
279 RETRO_LANGUAGE_GREEK = 17,
280 RETRO_LANGUAGE_TURKISH = 18,
281 RETRO_LANGUAGE_SLOVAK = 19,
282 RETRO_LANGUAGE_PERSIAN = 20,
283 RETRO_LANGUAGE_HEBREW = 21,
284 RETRO_LANGUAGE_ASTURIAN = 22,
285 RETRO_LANGUAGE_LAST,
286
287 /* Ensure sizeof(enum) == sizeof(int) */
288 RETRO_LANGUAGE_DUMMY = INT_MAX
289};
290
291/* Passed to retro_get_memory_data/size().
292 * If the memory type doesn't apply to the
293 * implementation NULL/0 can be returned.
294 */
295#define RETRO_MEMORY_MASK 0xff
296
297/* Regular save RAM. This RAM is usually found on a game cartridge,
298 * backed up by a battery.
299 * If save game data is too complex for a single memory buffer,
300 * the SAVE_DIRECTORY (preferably) or SYSTEM_DIRECTORY environment
301 * callback can be used. */
302#define RETRO_MEMORY_SAVE_RAM 0
303
304/* Some games have a built-in clock to keep track of time.
305 * This memory is usually just a couple of bytes to keep track of time.
306 */
307#define RETRO_MEMORY_RTC 1
308
309/* System ram lets a frontend peek into a game systems main RAM. */
310#define RETRO_MEMORY_SYSTEM_RAM 2
311
312/* Video ram lets a frontend peek into a game systems video RAM (VRAM). */
313#define RETRO_MEMORY_VIDEO_RAM 3
314
315/* Keysyms used for ID in input state callback when polling RETRO_KEYBOARD. */
316enum retro_key
317{
318 RETROK_UNKNOWN = 0,
319 RETROK_FIRST = 0,
320 RETROK_BACKSPACE = 8,
321 RETROK_TAB = 9,
322 RETROK_CLEAR = 12,
323 RETROK_RETURN = 13,
324 RETROK_PAUSE = 19,
325 RETROK_ESCAPE = 27,
326 RETROK_SPACE = 32,
327 RETROK_EXCLAIM = 33,
328 RETROK_QUOTEDBL = 34,
329 RETROK_HASH = 35,
330 RETROK_DOLLAR = 36,
331 RETROK_AMPERSAND = 38,
332 RETROK_QUOTE = 39,
333 RETROK_LEFTPAREN = 40,
334 RETROK_RIGHTPAREN = 41,
335 RETROK_ASTERISK = 42,
336 RETROK_PLUS = 43,
337 RETROK_COMMA = 44,
338 RETROK_MINUS = 45,
339 RETROK_PERIOD = 46,
340 RETROK_SLASH = 47,
341 RETROK_0 = 48,
342 RETROK_1 = 49,
343 RETROK_2 = 50,
344 RETROK_3 = 51,
345 RETROK_4 = 52,
346 RETROK_5 = 53,
347 RETROK_6 = 54,
348 RETROK_7 = 55,
349 RETROK_8 = 56,
350 RETROK_9 = 57,
351 RETROK_COLON = 58,
352 RETROK_SEMICOLON = 59,
353 RETROK_LESS = 60,
354 RETROK_EQUALS = 61,
355 RETROK_GREATER = 62,
356 RETROK_QUESTION = 63,
357 RETROK_AT = 64,
358 RETROK_LEFTBRACKET = 91,
359 RETROK_BACKSLASH = 92,
360 RETROK_RIGHTBRACKET = 93,
361 RETROK_CARET = 94,
362 RETROK_UNDERSCORE = 95,
363 RETROK_BACKQUOTE = 96,
364 RETROK_a = 97,
365 RETROK_b = 98,
366 RETROK_c = 99,
367 RETROK_d = 100,
368 RETROK_e = 101,
369 RETROK_f = 102,
370 RETROK_g = 103,
371 RETROK_h = 104,
372 RETROK_i = 105,
373 RETROK_j = 106,
374 RETROK_k = 107,
375 RETROK_l = 108,
376 RETROK_m = 109,
377 RETROK_n = 110,
378 RETROK_o = 111,
379 RETROK_p = 112,
380 RETROK_q = 113,
381 RETROK_r = 114,
382 RETROK_s = 115,
383 RETROK_t = 116,
384 RETROK_u = 117,
385 RETROK_v = 118,
386 RETROK_w = 119,
387 RETROK_x = 120,
388 RETROK_y = 121,
389 RETROK_z = 122,
390 RETROK_LEFTBRACE = 123,
391 RETROK_BAR = 124,
392 RETROK_RIGHTBRACE = 125,
393 RETROK_TILDE = 126,
394 RETROK_DELETE = 127,
395
396 RETROK_KP0 = 256,
397 RETROK_KP1 = 257,
398 RETROK_KP2 = 258,
399 RETROK_KP3 = 259,
400 RETROK_KP4 = 260,
401 RETROK_KP5 = 261,
402 RETROK_KP6 = 262,
403 RETROK_KP7 = 263,
404 RETROK_KP8 = 264,
405 RETROK_KP9 = 265,
406 RETROK_KP_PERIOD = 266,
407 RETROK_KP_DIVIDE = 267,
408 RETROK_KP_MULTIPLY = 268,
409 RETROK_KP_MINUS = 269,
410 RETROK_KP_PLUS = 270,
411 RETROK_KP_ENTER = 271,
412 RETROK_KP_EQUALS = 272,
413
414 RETROK_UP = 273,
415 RETROK_DOWN = 274,
416 RETROK_RIGHT = 275,
417 RETROK_LEFT = 276,
418 RETROK_INSERT = 277,
419 RETROK_HOME = 278,
420 RETROK_END = 279,
421 RETROK_PAGEUP = 280,
422 RETROK_PAGEDOWN = 281,
423
424 RETROK_F1 = 282,
425 RETROK_F2 = 283,
426 RETROK_F3 = 284,
427 RETROK_F4 = 285,
428 RETROK_F5 = 286,
429 RETROK_F6 = 287,
430 RETROK_F7 = 288,
431 RETROK_F8 = 289,
432 RETROK_F9 = 290,
433 RETROK_F10 = 291,
434 RETROK_F11 = 292,
435 RETROK_F12 = 293,
436 RETROK_F13 = 294,
437 RETROK_F14 = 295,
438 RETROK_F15 = 296,
439
440 RETROK_NUMLOCK = 300,
441 RETROK_CAPSLOCK = 301,
442 RETROK_SCROLLOCK = 302,
443 RETROK_RSHIFT = 303,
444 RETROK_LSHIFT = 304,
445 RETROK_RCTRL = 305,
446 RETROK_LCTRL = 306,
447 RETROK_RALT = 307,
448 RETROK_LALT = 308,
449 RETROK_RMETA = 309,
450 RETROK_LMETA = 310,
451 RETROK_LSUPER = 311,
452 RETROK_RSUPER = 312,
453 RETROK_MODE = 313,
454 RETROK_COMPOSE = 314,
455
456 RETROK_HELP = 315,
457 RETROK_PRINT = 316,
458 RETROK_SYSREQ = 317,
459 RETROK_BREAK = 318,
460 RETROK_MENU = 319,
461 RETROK_POWER = 320,
462 RETROK_EURO = 321,
463 RETROK_UNDO = 322,
464 RETROK_OEM_102 = 323,
465
466 RETROK_LAST,
467
468 RETROK_DUMMY = INT_MAX /* Ensure sizeof(enum) == sizeof(int) */
469};
470
471enum retro_mod
472{
473 RETROKMOD_NONE = 0x0000,
474
475 RETROKMOD_SHIFT = 0x01,
476 RETROKMOD_CTRL = 0x02,
477 RETROKMOD_ALT = 0x04,
478 RETROKMOD_META = 0x08,
479
480 RETROKMOD_NUMLOCK = 0x10,
481 RETROKMOD_CAPSLOCK = 0x20,
482 RETROKMOD_SCROLLOCK = 0x40,
483
484 RETROKMOD_DUMMY = INT_MAX /* Ensure sizeof(enum) == sizeof(int) */
485};
486
487/* If set, this call is not part of the public libretro API yet. It can
488 * change or be removed at any time. */
489#define RETRO_ENVIRONMENT_EXPERIMENTAL 0x10000
490/* Environment callback to be used internally in frontend. */
491#define RETRO_ENVIRONMENT_PRIVATE 0x20000
492
493/* Environment commands. */
494#define RETRO_ENVIRONMENT_SET_ROTATION 1 /* const unsigned * --
495 * Sets screen rotation of graphics.
496 * Valid values are 0, 1, 2, 3, which rotates screen by 0, 90, 180,
497 * 270 degrees counter-clockwise respectively.
498 */
499#define RETRO_ENVIRONMENT_GET_OVERSCAN 2 /* bool * --
500 * NOTE: As of 2019 this callback is considered deprecated in favor of
501 * using core options to manage overscan in a more nuanced, core-specific way.
502 *
503 * Boolean value whether or not the implementation should use overscan,
504 * or crop away overscan.
505 */
506#define RETRO_ENVIRONMENT_GET_CAN_DUPE 3 /* bool * --
507 * Boolean value whether or not frontend supports frame duping,
508 * passing NULL to video frame callback.
509 */
510
511 /* Environ 4, 5 are no longer supported (GET_VARIABLE / SET_VARIABLES),
512 * and reserved to avoid possible ABI clash.
513 */
514
515#define RETRO_ENVIRONMENT_SET_MESSAGE 6 /* const struct retro_message * --
516 * Sets a message to be displayed in implementation-specific manner
517 * for a certain amount of 'frames'.
518 * Should not be used for trivial messages, which should simply be
519 * logged via RETRO_ENVIRONMENT_GET_LOG_INTERFACE (or as a
520 * fallback, stderr).
521 */
522#define RETRO_ENVIRONMENT_SHUTDOWN 7 /* N/A (NULL) --
523 * Requests the frontend to shutdown.
524 * Should only be used if game has a specific
525 * way to shutdown the game from a menu item or similar.
526 */
527#define RETRO_ENVIRONMENT_SET_PERFORMANCE_LEVEL 8
528 /* const unsigned * --
529 * Gives a hint to the frontend how demanding this implementation
530 * is on a system. E.g. reporting a level of 2 means
531 * this implementation should run decently on all frontends
532 * of level 2 and up.
533 *
534 * It can be used by the frontend to potentially warn
535 * about too demanding implementations.
536 *
537 * The levels are "floating".
538 *
539 * This function can be called on a per-game basis,
540 * as certain games an implementation can play might be
541 * particularly demanding.
542 * If called, it should be called in retro_load_game().
543 */
544#define RETRO_ENVIRONMENT_GET_SYSTEM_DIRECTORY 9
545 /* const char ** --
546 * Returns the "system" directory of the frontend.
547 * This directory can be used to store system specific
548 * content such as BIOSes, configuration data, etc.
549 * The returned value can be NULL.
550 * If so, no such directory is defined,
551 * and it's up to the implementation to find a suitable directory.
552 *
553 * NOTE: Some cores used this folder also for "save" data such as
554 * memory cards, etc, for lack of a better place to put it.
555 * This is now discouraged, and if possible, cores should try to
556 * use the new GET_SAVE_DIRECTORY.
557 */
558#define RETRO_ENVIRONMENT_SET_PIXEL_FORMAT 10
559 /* const enum retro_pixel_format * --
560 * Sets the internal pixel format used by the implementation.
561 * The default pixel format is RETRO_PIXEL_FORMAT_0RGB1555.
562 * This pixel format however, is deprecated (see enum retro_pixel_format).
563 * If the call returns false, the frontend does not support this pixel
564 * format.
565 *
566 * This function should be called inside retro_load_game() or
567 * retro_get_system_av_info().
568 */
569#define RETRO_ENVIRONMENT_SET_INPUT_DESCRIPTORS 11
570 /* const struct retro_input_descriptor * --
571 * Sets an array of retro_input_descriptors.
572 * It is up to the frontend to present this in a usable way.
573 * The array is terminated by retro_input_descriptor::description
574 * being set to NULL.
575 * This function can be called at any time, but it is recommended
576 * to call it as early as possible.
577 */
578#define RETRO_ENVIRONMENT_SET_KEYBOARD_CALLBACK 12
579 /* const struct retro_keyboard_callback * --
580 * Sets a callback function used to notify core about keyboard events.
581 */
582#define RETRO_ENVIRONMENT_SET_DISK_CONTROL_INTERFACE 13
583 /* const struct retro_disk_control_callback * --
584 * Sets an interface which frontend can use to eject and insert
585 * disk images.
586 * This is used for games which consist of multiple images and
587 * must be manually swapped out by the user (e.g. PSX).
588 */
589#define RETRO_ENVIRONMENT_SET_HW_RENDER 14
590 /* struct retro_hw_render_callback * --
591 * Sets an interface to let a libretro core render with
592 * hardware acceleration.
593 * Should be called in retro_load_game().
594 * If successful, libretro cores will be able to render to a
595 * frontend-provided framebuffer.
596 * The size of this framebuffer will be at least as large as
597 * max_width/max_height provided in get_av_info().
598 * If HW rendering is used, pass only RETRO_HW_FRAME_BUFFER_VALID or
599 * NULL to retro_video_refresh_t.
600 */
601#define RETRO_ENVIRONMENT_GET_VARIABLE 15
602 /* struct retro_variable * --
603 * Interface to acquire user-defined information from environment
604 * that cannot feasibly be supported in a multi-system way.
605 * 'key' should be set to a key which has already been set by
606 * SET_VARIABLES.
607 * 'data' will be set to a value or NULL.
608 */
609#define RETRO_ENVIRONMENT_SET_VARIABLES 16
610 /* const struct retro_variable * --
611 * Allows an implementation to signal the environment
612 * which variables it might want to check for later using
613 * GET_VARIABLE.
614 * This allows the frontend to present these variables to
615 * a user dynamically.
616 * This should be called the first time as early as
617 * possible (ideally in retro_set_environment).
618 * Afterward it may be called again for the core to communicate
619 * updated options to the frontend, but the number of core
620 * options must not change from the number in the initial call.
621 *
622 * 'data' points to an array of retro_variable structs
623 * terminated by a { NULL, NULL } element.
624 * retro_variable::key should be namespaced to not collide
625 * with other implementations' keys. E.g. A core called
626 * 'foo' should use keys named as 'foo_option'.
627 * retro_variable::value should contain a human readable
628 * description of the key as well as a '|' delimited list
629 * of expected values.
630 *
631 * The number of possible options should be very limited,
632 * i.e. it should be feasible to cycle through options
633 * without a keyboard.
634 *
635 * First entry should be treated as a default.
636 *
637 * Example entry:
638 * { "foo_option", "Speed hack coprocessor X; false|true" }
639 *
640 * Text before first ';' is description. This ';' must be
641 * followed by a space, and followed by a list of possible
642 * values split up with '|'.
643 *
644 * Only strings are operated on. The possible values will
645 * generally be displayed and stored as-is by the frontend.
646 */
647#define RETRO_ENVIRONMENT_GET_VARIABLE_UPDATE 17
648 /* bool * --
649 * Result is set to true if some variables are updated by
650 * frontend since last call to RETRO_ENVIRONMENT_GET_VARIABLE.
651 * Variables should be queried with GET_VARIABLE.
652 */
653#define RETRO_ENVIRONMENT_SET_SUPPORT_NO_GAME 18
654 /* const bool * --
655 * If true, the libretro implementation supports calls to
656 * retro_load_game() with NULL as argument.
657 * Used by cores which can run without particular game data.
658 * This should be called within retro_set_environment() only.
659 */
660#define RETRO_ENVIRONMENT_GET_LIBRETRO_PATH 19
661 /* const char ** --
662 * Retrieves the absolute path from where this libretro
663 * implementation was loaded.
664 * NULL is returned if the libretro was loaded statically
665 * (i.e. linked statically to frontend), or if the path cannot be
666 * determined.
667 * Mostly useful in cooperation with SET_SUPPORT_NO_GAME as assets can
668 * be loaded without ugly hacks.
669 */
670
671 /* Environment 20 was an obsolete version of SET_AUDIO_CALLBACK.
672 * It was not used by any known core at the time,
673 * and was removed from the API. */
674#define RETRO_ENVIRONMENT_SET_FRAME_TIME_CALLBACK 21
675 /* const struct retro_frame_time_callback * --
676 * Lets the core know how much time has passed since last
677 * invocation of retro_run().
678 * The frontend can tamper with the timing to fake fast-forward,
679 * slow-motion, frame stepping, etc.
680 * In this case the delta time will use the reference value
681 * in frame_time_callback..
682 */
683#define RETRO_ENVIRONMENT_SET_AUDIO_CALLBACK 22
684 /* const struct retro_audio_callback * --
685 * Sets an interface which is used to notify a libretro core about audio
686 * being available for writing.
687 * The callback can be called from any thread, so a core using this must
688 * have a thread safe audio implementation.
689 * It is intended for games where audio and video are completely
690 * asynchronous and audio can be generated on the fly.
691 * This interface is not recommended for use with emulators which have
692 * highly synchronous audio.
693 *
694 * The callback only notifies about writability; the libretro core still
695 * has to call the normal audio callbacks
696 * to write audio. The audio callbacks must be called from within the
697 * notification callback.
698 * The amount of audio data to write is up to the implementation.
699 * Generally, the audio callback will be called continously in a loop.
700 *
701 * Due to thread safety guarantees and lack of sync between audio and
702 * video, a frontend can selectively disallow this interface based on
703 * internal configuration. A core using this interface must also
704 * implement the "normal" audio interface.
705 *
706 * A libretro core using SET_AUDIO_CALLBACK should also make use of
707 * SET_FRAME_TIME_CALLBACK.
708 */
709#define RETRO_ENVIRONMENT_GET_RUMBLE_INTERFACE 23
710 /* struct retro_rumble_interface * --
711 * Gets an interface which is used by a libretro core to set
712 * state of rumble motors in controllers.
713 * A strong and weak motor is supported, and they can be
714 * controlled indepedently.
715 */
716#define RETRO_ENVIRONMENT_GET_INPUT_DEVICE_CAPABILITIES 24
717 /* uint64_t * --
718 * Gets a bitmask telling which device type are expected to be
719 * handled properly in a call to retro_input_state_t.
720 * Devices which are not handled or recognized always return
721 * 0 in retro_input_state_t.
722 * Example bitmask: caps = (1 << RETRO_DEVICE_JOYPAD) | (1 << RETRO_DEVICE_ANALOG).
723 * Should only be called in retro_run().
724 */
725#define RETRO_ENVIRONMENT_GET_SENSOR_INTERFACE (25 | RETRO_ENVIRONMENT_EXPERIMENTAL)
726 /* struct retro_sensor_interface * --
727 * Gets access to the sensor interface.
728 * The purpose of this interface is to allow
729 * setting state related to sensors such as polling rate,
730 * enabling/disable it entirely, etc.
731 * Reading sensor state is done via the normal
732 * input_state_callback API.
733 */
734#define RETRO_ENVIRONMENT_GET_CAMERA_INTERFACE (26 | RETRO_ENVIRONMENT_EXPERIMENTAL)
735 /* struct retro_camera_callback * --
736 * Gets an interface to a video camera driver.
737 * A libretro core can use this interface to get access to a
738 * video camera.
739 * New video frames are delivered in a callback in same
740 * thread as retro_run().
741 *
742 * GET_CAMERA_INTERFACE should be called in retro_load_game().
743 *
744 * Depending on the camera implementation used, camera frames
745 * will be delivered as a raw framebuffer,
746 * or as an OpenGL texture directly.
747 *
748 * The core has to tell the frontend here which types of
749 * buffers can be handled properly.
750 * An OpenGL texture can only be handled when using a
751 * libretro GL core (SET_HW_RENDER).
752 * It is recommended to use a libretro GL core when
753 * using camera interface.
754 *
755 * The camera is not started automatically. The retrieved start/stop
756 * functions must be used to explicitly
757 * start and stop the camera driver.
758 */
759#define RETRO_ENVIRONMENT_GET_LOG_INTERFACE 27
760 /* struct retro_log_callback * --
761 * Gets an interface for logging. This is useful for
762 * logging in a cross-platform way
763 * as certain platforms cannot use stderr for logging.
764 * It also allows the frontend to
765 * show logging information in a more suitable way.
766 * If this interface is not used, libretro cores should
767 * log to stderr as desired.
768 */
769#define RETRO_ENVIRONMENT_GET_PERF_INTERFACE 28
770 /* struct retro_perf_callback * --
771 * Gets an interface for performance counters. This is useful
772 * for performance logging in a cross-platform way and for detecting
773 * architecture-specific features, such as SIMD support.
774 */
775#define RETRO_ENVIRONMENT_GET_LOCATION_INTERFACE 29
776 /* struct retro_location_callback * --
777 * Gets access to the location interface.
778 * The purpose of this interface is to be able to retrieve
779 * location-based information from the host device,
780 * such as current latitude / longitude.
781 */
782#define RETRO_ENVIRONMENT_GET_CONTENT_DIRECTORY 30 /* Old name, kept for compatibility. */
783#define RETRO_ENVIRONMENT_GET_CORE_ASSETS_DIRECTORY 30
784 /* const char ** --
785 * Returns the "core assets" directory of the frontend.
786 * This directory can be used to store specific assets that the
787 * core relies upon, such as art assets,
788 * input data, etc etc.
789 * The returned value can be NULL.
790 * If so, no such directory is defined,
791 * and it's up to the implementation to find a suitable directory.
792 */
793#define RETRO_ENVIRONMENT_GET_SAVE_DIRECTORY 31
794 /* const char ** --
795 * Returns the "save" directory of the frontend, unless there is no
796 * save directory available. The save directory should be used to
797 * store SRAM, memory cards, high scores, etc, if the libretro core
798 * cannot use the regular memory interface (retro_get_memory_data()).
799 *
800 * If the frontend cannot designate a save directory, it will return
801 * NULL to indicate that the core should attempt to operate without a
802 * save directory set.
803 *
804 * NOTE: early libretro cores used the system directory for save
805 * files. Cores that need to be backwards-compatible can still check
806 * GET_SYSTEM_DIRECTORY.
807 */
808#define RETRO_ENVIRONMENT_SET_SYSTEM_AV_INFO 32
809 /* const struct retro_system_av_info * --
810 * Sets a new av_info structure. This can only be called from
811 * within retro_run().
812 * This should *only* be used if the core is completely altering the
813 * internal resolutions, aspect ratios, timings, sampling rate, etc.
814 * Calling this can require a full reinitialization of video/audio
815 * drivers in the frontend,
816 *
817 * so it is important to call it very sparingly, and usually only with
818 * the users explicit consent.
819 * An eventual driver reinitialize will happen so that video and
820 * audio callbacks
821 * happening after this call within the same retro_run() call will
822 * target the newly initialized driver.
823 *
824 * This callback makes it possible to support configurable resolutions
825 * in games, which can be useful to
826 * avoid setting the "worst case" in max_width/max_height.
827 *
828 * ***HIGHLY RECOMMENDED*** Do not call this callback every time
829 * resolution changes in an emulator core if it's
830 * expected to be a temporary change, for the reasons of possible
831 * driver reinitialization.
832 * This call is not a free pass for not trying to provide
833 * correct values in retro_get_system_av_info(). If you need to change
834 * things like aspect ratio or nominal width/height,
835 * use RETRO_ENVIRONMENT_SET_GEOMETRY, which is a softer variant
836 * of SET_SYSTEM_AV_INFO.
837 *
838 * If this returns false, the frontend does not acknowledge a
839 * changed av_info struct.
840 */
841#define RETRO_ENVIRONMENT_SET_PROC_ADDRESS_CALLBACK 33
842 /* const struct retro_get_proc_address_interface * --
843 * Allows a libretro core to announce support for the
844 * get_proc_address() interface.
845 * This interface allows for a standard way to extend libretro where
846 * use of environment calls are too indirect,
847 * e.g. for cases where the frontend wants to call directly into the core.
848 *
849 * If a core wants to expose this interface, SET_PROC_ADDRESS_CALLBACK
850 * **MUST** be called from within retro_set_environment().
851 */
852#define RETRO_ENVIRONMENT_SET_SUBSYSTEM_INFO 34
853 /* const struct retro_subsystem_info * --
854 * This environment call introduces the concept of libretro "subsystems".
855 * A subsystem is a variant of a libretro core which supports
856 * different kinds of games.
857 * The purpose of this is to support e.g. emulators which might
858 * have special needs, e.g. Super Nintendo's Super GameBoy, Sufami Turbo.
859 * It can also be used to pick among subsystems in an explicit way
860 * if the libretro implementation is a multi-system emulator itself.
861 *
862 * Loading a game via a subsystem is done with retro_load_game_special(),
863 * and this environment call allows a libretro core to expose which
864 * subsystems are supported for use with retro_load_game_special().
865 * A core passes an array of retro_game_special_info which is terminated
866 * with a zeroed out retro_game_special_info struct.
867 *
868 * If a core wants to use this functionality, SET_SUBSYSTEM_INFO
869 * **MUST** be called from within retro_set_environment().
870 */
871#define RETRO_ENVIRONMENT_SET_CONTROLLER_INFO 35
872 /* const struct retro_controller_info * --
873 * This environment call lets a libretro core tell the frontend
874 * which controller subclasses are recognized in calls to
875 * retro_set_controller_port_device().
876 *
877 * Some emulators such as Super Nintendo support multiple lightgun
878 * types which must be specifically selected from. It is therefore
879 * sometimes necessary for a frontend to be able to tell the core
880 * about a special kind of input device which is not specifcally
881 * provided by the Libretro API.
882 *
883 * In order for a frontend to understand the workings of those devices,
884 * they must be defined as a specialized subclass of the generic device
885 * types already defined in the libretro API.
886 *
887 * The core must pass an array of const struct retro_controller_info which
888 * is terminated with a blanked out struct. Each element of the
889 * retro_controller_info struct corresponds to the ascending port index
890 * that is passed to retro_set_controller_port_device() when that function
891 * is called to indicate to the core that the frontend has changed the
892 * active device subclass. SEE ALSO: retro_set_controller_port_device()
893 *
894 * The ascending input port indexes provided by the core in the struct
895 * are generally presented by frontends as ascending User # or Player #,
896 * such as Player 1, Player 2, Player 3, etc. Which device subclasses are
897 * supported can vary per input port.
898 *
899 * The first inner element of each entry in the retro_controller_info array
900 * is a retro_controller_description struct that specifies the names and
901 * codes of all device subclasses that are available for the corresponding
902 * User or Player, beginning with the generic Libretro device that the
903 * subclasses are derived from. The second inner element of each entry is the
904 * total number of subclasses that are listed in the retro_controller_description.
905 *
906 * NOTE: Even if special device types are set in the libretro core,
907 * libretro should only poll input based on the base input device types.
908 */
909#define RETRO_ENVIRONMENT_SET_MEMORY_MAPS (36 | RETRO_ENVIRONMENT_EXPERIMENTAL)
910 /* const struct retro_memory_map * --
911 * This environment call lets a libretro core tell the frontend
912 * about the memory maps this core emulates.
913 * This can be used to implement, for example, cheats in a core-agnostic way.
914 *
915 * Should only be used by emulators; it doesn't make much sense for
916 * anything else.
917 * It is recommended to expose all relevant pointers through
918 * retro_get_memory_* as well.
919 *
920 * Can be called from retro_init and retro_load_game.
921 */
922#define RETRO_ENVIRONMENT_SET_GEOMETRY 37
923 /* const struct retro_game_geometry * --
924 * This environment call is similar to SET_SYSTEM_AV_INFO for changing
925 * video parameters, but provides a guarantee that drivers will not be
926 * reinitialized.
927 * This can only be called from within retro_run().
928 *
929 * The purpose of this call is to allow a core to alter nominal
930 * width/heights as well as aspect ratios on-the-fly, which can be
931 * useful for some emulators to change in run-time.
932 *
933 * max_width/max_height arguments are ignored and cannot be changed
934 * with this call as this could potentially require a reinitialization or a
935 * non-constant time operation.
936 * If max_width/max_height are to be changed, SET_SYSTEM_AV_INFO is required.
937 *
938 * A frontend must guarantee that this environment call completes in
939 * constant time.
940 */
941#define RETRO_ENVIRONMENT_GET_USERNAME 38
942 /* const char **
943 * Returns the specified username of the frontend, if specified by the user.
944 * This username can be used as a nickname for a core that has online facilities
945 * or any other mode where personalization of the user is desirable.
946 * The returned value can be NULL.
947 * If this environ callback is used by a core that requires a valid username,
948 * a default username should be specified by the core.
949 */
950#define RETRO_ENVIRONMENT_GET_LANGUAGE 39
951 /* unsigned * --
952 * Returns the specified language of the frontend, if specified by the user.
953 * It can be used by the core for localization purposes.
954 */
955#define RETRO_ENVIRONMENT_GET_CURRENT_SOFTWARE_FRAMEBUFFER (40 | RETRO_ENVIRONMENT_EXPERIMENTAL)
956 /* struct retro_framebuffer * --
957 * Returns a preallocated framebuffer which the core can use for rendering
958 * the frame into when not using SET_HW_RENDER.
959 * The framebuffer returned from this call must not be used
960 * after the current call to retro_run() returns.
961 *
962 * The goal of this call is to allow zero-copy behavior where a core
963 * can render directly into video memory, avoiding extra bandwidth cost by copying
964 * memory from core to video memory.
965 *
966 * If this call succeeds and the core renders into it,
967 * the framebuffer pointer and pitch can be passed to retro_video_refresh_t.
968 * If the buffer from GET_CURRENT_SOFTWARE_FRAMEBUFFER is to be used,
969 * the core must pass the exact
970 * same pointer as returned by GET_CURRENT_SOFTWARE_FRAMEBUFFER;
971 * i.e. passing a pointer which is offset from the
972 * buffer is undefined. The width, height and pitch parameters
973 * must also match exactly to the values obtained from GET_CURRENT_SOFTWARE_FRAMEBUFFER.
974 *
975 * It is possible for a frontend to return a different pixel format
976 * than the one used in SET_PIXEL_FORMAT. This can happen if the frontend
977 * needs to perform conversion.
978 *
979 * It is still valid for a core to render to a different buffer
980 * even if GET_CURRENT_SOFTWARE_FRAMEBUFFER succeeds.
981 *
982 * A frontend must make sure that the pointer obtained from this function is
983 * writeable (and readable).
984 */
985#define RETRO_ENVIRONMENT_GET_HW_RENDER_INTERFACE (41 | RETRO_ENVIRONMENT_EXPERIMENTAL)
986 /* const struct retro_hw_render_interface ** --
987 * Returns an API specific rendering interface for accessing API specific data.
988 * Not all HW rendering APIs support or need this.
989 * The contents of the returned pointer is specific to the rendering API
990 * being used. See the various headers like libretro_vulkan.h, etc.
991 *
992 * GET_HW_RENDER_INTERFACE cannot be called before context_reset has been called.
993 * Similarly, after context_destroyed callback returns,
994 * the contents of the HW_RENDER_INTERFACE are invalidated.
995 */
996#define RETRO_ENVIRONMENT_SET_SUPPORT_ACHIEVEMENTS (42 | RETRO_ENVIRONMENT_EXPERIMENTAL)
997 /* const bool * --
998 * If true, the libretro implementation supports achievements
999 * either via memory descriptors set with RETRO_ENVIRONMENT_SET_MEMORY_MAPS
1000 * or via retro_get_memory_data/retro_get_memory_size.
1001 *
1002 * This must be called before the first call to retro_run.
1003 */
1004#define RETRO_ENVIRONMENT_SET_HW_RENDER_CONTEXT_NEGOTIATION_INTERFACE (43 | RETRO_ENVIRONMENT_EXPERIMENTAL)
1005 /* const struct retro_hw_render_context_negotiation_interface * --
1006 * Sets an interface which lets the libretro core negotiate with frontend how a context is created.
1007 * The semantics of this interface depends on which API is used in SET_HW_RENDER earlier.
1008 * This interface will be used when the frontend is trying to create a HW rendering context,
1009 * so it will be used after SET_HW_RENDER, but before the context_reset callback.
1010 */
1011#define RETRO_ENVIRONMENT_SET_SERIALIZATION_QUIRKS 44
1012 /* uint64_t * --
1013 * Sets quirk flags associated with serialization. The frontend will zero any flags it doesn't
1014 * recognize or support. Should be set in either retro_init or retro_load_game, but not both.
1015 */
1016#define RETRO_ENVIRONMENT_SET_HW_SHARED_CONTEXT (44 | RETRO_ENVIRONMENT_EXPERIMENTAL)
1017 /* N/A (null) * --
1018 * The frontend will try to use a 'shared' hardware context (mostly applicable
1019 * to OpenGL) when a hardware context is being set up.
1020 *
1021 * Returns true if the frontend supports shared hardware contexts and false
1022 * if the frontend does not support shared hardware contexts.
1023 *
1024 * This will do nothing on its own until SET_HW_RENDER env callbacks are
1025 * being used.
1026 */
1027#define RETRO_ENVIRONMENT_GET_VFS_INTERFACE (45 | RETRO_ENVIRONMENT_EXPERIMENTAL)
1028 /* struct retro_vfs_interface_info * --
1029 * Gets access to the VFS interface.
1030 * VFS presence needs to be queried prior to load_game or any
1031 * get_system/save/other_directory being called to let front end know
1032 * core supports VFS before it starts handing out paths.
1033 * It is recomended to do so in retro_set_environment
1034 */
1035#define RETRO_ENVIRONMENT_GET_LED_INTERFACE (46 | RETRO_ENVIRONMENT_EXPERIMENTAL)
1036 /* struct retro_led_interface * --
1037 * Gets an interface which is used by a libretro core to set
1038 * state of LEDs.
1039 */
1040#define RETRO_ENVIRONMENT_GET_AUDIO_VIDEO_ENABLE (47 | RETRO_ENVIRONMENT_EXPERIMENTAL)
1041 /* int * --
1042 * Tells the core if the frontend wants audio or video.
1043 * If disabled, the frontend will discard the audio or video,
1044 * so the core may decide to skip generating a frame or generating audio.
1045 * This is mainly used for increasing performance.
1046 * Bit 0 (value 1): Enable Video
1047 * Bit 1 (value 2): Enable Audio
1048 * Bit 2 (value 4): Use Fast Savestates.
1049 * Bit 3 (value 8): Hard Disable Audio
1050 * Other bits are reserved for future use and will default to zero.
1051 * If video is disabled:
1052 * * The frontend wants the core to not generate any video,
1053 * including presenting frames via hardware acceleration.
1054 * * The frontend's video frame callback will do nothing.
1055 * * After running the frame, the video output of the next frame should be
1056 * no different than if video was enabled, and saving and loading state
1057 * should have no issues.
1058 * If audio is disabled:
1059 * * The frontend wants the core to not generate any audio.
1060 * * The frontend's audio callbacks will do nothing.
1061 * * After running the frame, the audio output of the next frame should be
1062 * no different than if audio was enabled, and saving and loading state
1063 * should have no issues.
1064 * Fast Savestates:
1065 * * Guaranteed to be created by the same binary that will load them.
1066 * * Will not be written to or read from the disk.
1067 * * Suggest that the core assumes loading state will succeed.
1068 * * Suggest that the core updates its memory buffers in-place if possible.
1069 * * Suggest that the core skips clearing memory.
1070 * * Suggest that the core skips resetting the system.
1071 * * Suggest that the core may skip validation steps.
1072 * Hard Disable Audio:
1073 * * Used for a secondary core when running ahead.
1074 * * Indicates that the frontend will never need audio from the core.
1075 * * Suggests that the core may stop synthesizing audio, but this should not
1076 * compromise emulation accuracy.
1077 * * Audio output for the next frame does not matter, and the frontend will
1078 * never need an accurate audio state in the future.
1079 * * State will never be saved when using Hard Disable Audio.
1080 */
1081#define RETRO_ENVIRONMENT_GET_MIDI_INTERFACE (48 | RETRO_ENVIRONMENT_EXPERIMENTAL)
1082 /* struct retro_midi_interface ** --
1083 * Returns a MIDI interface that can be used for raw data I/O.
1084 */
1085
1086#define RETRO_ENVIRONMENT_GET_FASTFORWARDING (49 | RETRO_ENVIRONMENT_EXPERIMENTAL)
1087 /* bool * --
1088 * Boolean value that indicates whether or not the frontend is in
1089 * fastforwarding mode.
1090 */
1091
1092#define RETRO_ENVIRONMENT_GET_TARGET_REFRESH_RATE (50 | RETRO_ENVIRONMENT_EXPERIMENTAL)
1093 /* float * --
1094 * Float value that lets us know what target refresh rate
1095 * is curently in use by the frontend.
1096 *
1097 * The core can use the returned value to set an ideal
1098 * refresh rate/framerate.
1099 */
1100
1101#define RETRO_ENVIRONMENT_GET_INPUT_BITMASKS (51 | RETRO_ENVIRONMENT_EXPERIMENTAL)
1102 /* bool * --
1103 * Boolean value that indicates whether or not the frontend supports
1104 * input bitmasks being returned by retro_input_state_t. The advantage
1105 * of this is that retro_input_state_t has to be only called once to
1106 * grab all button states instead of multiple times.
1107 *
1108 * If it returns true, you can pass RETRO_DEVICE_ID_JOYPAD_MASK as 'id'
1109 * to retro_input_state_t (make sure 'device' is set to RETRO_DEVICE_JOYPAD).
1110 * It will return a bitmask of all the digital buttons.
1111 */
1112
1113#define RETRO_ENVIRONMENT_GET_CORE_OPTIONS_VERSION 52
1114 /* unsigned * --
1115 * Unsigned value is the API version number of the core options
1116 * interface supported by the frontend. If callback return false,
1117 * API version is assumed to be 0.
1118 *
1119 * In legacy code, core options are set by passing an array of
1120 * retro_variable structs to RETRO_ENVIRONMENT_SET_VARIABLES.
1121 * This may be still be done regardless of the core options
1122 * interface version.
1123 *
1124 * If version is >= 1 however, core options may instead be set by
1125 * passing an array of retro_core_option_definition structs to
1126 * RETRO_ENVIRONMENT_SET_CORE_OPTIONS, or a 2D array of
1127 * retro_core_option_definition structs to RETRO_ENVIRONMENT_SET_CORE_OPTIONS_INTL.
1128 * This allows the core to additionally set option sublabel information
1129 * and/or provide localisation support.
1130 */
1131
1132#define RETRO_ENVIRONMENT_SET_CORE_OPTIONS 53
1133 /* const struct retro_core_option_definition ** --
1134 * Allows an implementation to signal the environment
1135 * which variables it might want to check for later using
1136 * GET_VARIABLE.
1137 * This allows the frontend to present these variables to
1138 * a user dynamically.
1139 * This should only be called if RETRO_ENVIRONMENT_GET_CORE_OPTIONS_VERSION
1140 * returns an API version of >= 1.
1141 * This should be called instead of RETRO_ENVIRONMENT_SET_VARIABLES.
1142 * This should be called the first time as early as
1143 * possible (ideally in retro_set_environment).
1144 * Afterwards it may be called again for the core to communicate
1145 * updated options to the frontend, but the number of core
1146 * options must not change from the number in the initial call.
1147 *
1148 * 'data' points to an array of retro_core_option_definition structs
1149 * terminated by a { NULL, NULL, NULL, {{0}}, NULL } element.
1150 * retro_core_option_definition::key should be namespaced to not collide
1151 * with other implementations' keys. e.g. A core called
1152 * 'foo' should use keys named as 'foo_option'.
1153 * retro_core_option_definition::desc should contain a human readable
1154 * description of the key.
1155 * retro_core_option_definition::info should contain any additional human
1156 * readable information text that a typical user may need to
1157 * understand the functionality of the option.
1158 * retro_core_option_definition::values is an array of retro_core_option_value
1159 * structs terminated by a { NULL, NULL } element.
1160 * > retro_core_option_definition::values[index].value is an expected option
1161 * value.
1162 * > retro_core_option_definition::values[index].label is a human readable
1163 * label used when displaying the value on screen. If NULL,
1164 * the value itself is used.
1165 * retro_core_option_definition::default_value is the default core option
1166 * setting. It must match one of the expected option values in the
1167 * retro_core_option_definition::values array. If it does not, or the
1168 * default value is NULL, the first entry in the
1169 * retro_core_option_definition::values array is treated as the default.
1170 *
1171 * The number of possible options should be very limited,
1172 * and must be less than RETRO_NUM_CORE_OPTION_VALUES_MAX.
1173 * i.e. it should be feasible to cycle through options
1174 * without a keyboard.
1175 *
1176 * Example entry:
1177 * {
1178 * "foo_option",
1179 * "Speed hack coprocessor X",
1180 * "Provides increased performance at the expense of reduced accuracy",
1181 * {
1182 * { "false", NULL },
1183 * { "true", NULL },
1184 * { "unstable", "Turbo (Unstable)" },
1185 * { NULL, NULL },
1186 * },
1187 * "false"
1188 * }
1189 *
1190 * Only strings are operated on. The possible values will
1191 * generally be displayed and stored as-is by the frontend.
1192 */
1193
1194#define RETRO_ENVIRONMENT_SET_CORE_OPTIONS_INTL 54
1195 /* const struct retro_core_options_intl * --
1196 * Allows an implementation to signal the environment
1197 * which variables it might want to check for later using
1198 * GET_VARIABLE.
1199 * This allows the frontend to present these variables to
1200 * a user dynamically.
1201 * This should only be called if RETRO_ENVIRONMENT_GET_CORE_OPTIONS_VERSION
1202 * returns an API version of >= 1.
1203 * This should be called instead of RETRO_ENVIRONMENT_SET_VARIABLES.
1204 * This should be called the first time as early as
1205 * possible (ideally in retro_set_environment).
1206 * Afterwards it may be called again for the core to communicate
1207 * updated options to the frontend, but the number of core
1208 * options must not change from the number in the initial call.
1209 *
1210 * This is fundamentally the same as RETRO_ENVIRONMENT_SET_CORE_OPTIONS,
1211 * with the addition of localisation support. The description of the
1212 * RETRO_ENVIRONMENT_SET_CORE_OPTIONS callback should be consulted
1213 * for further details.
1214 *
1215 * 'data' points to a retro_core_options_intl struct.
1216 *
1217 * retro_core_options_intl::us is a pointer to an array of
1218 * retro_core_option_definition structs defining the US English
1219 * core options implementation. It must point to a valid array.
1220 *
1221 * retro_core_options_intl::local is a pointer to an array of
1222 * retro_core_option_definition structs defining core options for
1223 * the current frontend language. It may be NULL (in which case
1224 * retro_core_options_intl::us is used by the frontend). Any items
1225 * missing from this array will be read from retro_core_options_intl::us
1226 * instead.
1227 *
1228 * NOTE: Default core option values are always taken from the
1229 * retro_core_options_intl::us array. Any default values in
1230 * retro_core_options_intl::local array will be ignored.
1231 */
1232
1233#define RETRO_ENVIRONMENT_SET_CORE_OPTIONS_DISPLAY 55
1234 /* struct retro_core_option_display * --
1235 *
1236 * Allows an implementation to signal the environment to show
1237 * or hide a variable when displaying core options. This is
1238 * considered a *suggestion*. The frontend is free to ignore
1239 * this callback, and its implementation not considered mandatory.
1240 *
1241 * 'data' points to a retro_core_option_display struct
1242 *
1243 * retro_core_option_display::key is a variable identifier
1244 * which has already been set by SET_VARIABLES/SET_CORE_OPTIONS.
1245 *
1246 * retro_core_option_display::visible is a boolean, specifying
1247 * whether variable should be displayed
1248 *
1249 * Note that all core option variables will be set visible by
1250 * default when calling SET_VARIABLES/SET_CORE_OPTIONS.
1251 */
1252
1253#define RETRO_ENVIRONMENT_GET_PREFERRED_HW_RENDER 56
1254 /* unsigned * --
1255 *
1256 * Allows an implementation to ask frontend preferred hardware
1257 * context to use. Core should use this information to deal
1258 * with what specific context to request with SET_HW_RENDER.
1259 *
1260 * 'data' points to an unsigned variable
1261 */
1262
1263#define RETRO_ENVIRONMENT_GET_DISK_CONTROL_INTERFACE_VERSION 57
1264 /* unsigned * --
1265 * Unsigned value is the API version number of the disk control
1266 * interface supported by the frontend. If callback return false,
1267 * API version is assumed to be 0.
1268 *
1269 * In legacy code, the disk control interface is defined by passing
1270 * a struct of type retro_disk_control_callback to
1271 * RETRO_ENVIRONMENT_SET_DISK_CONTROL_INTERFACE.
1272 * This may be still be done regardless of the disk control
1273 * interface version.
1274 *
1275 * If version is >= 1 however, the disk control interface may
1276 * instead be defined by passing a struct of type
1277 * retro_disk_control_ext_callback to
1278 * RETRO_ENVIRONMENT_SET_DISK_CONTROL_EXT_INTERFACE.
1279 * This allows the core to provide additional information about
1280 * disk images to the frontend and/or enables extra
1281 * disk control functionality by the frontend.
1282 */
1283
1284#define RETRO_ENVIRONMENT_SET_DISK_CONTROL_EXT_INTERFACE 58
1285 /* const struct retro_disk_control_ext_callback * --
1286 * Sets an interface which frontend can use to eject and insert
1287 * disk images, and also obtain information about individual
1288 * disk image files registered by the core.
1289 * This is used for games which consist of multiple images and
1290 * must be manually swapped out by the user (e.g. PSX, floppy disk
1291 * based systems).
1292 */
1293
1294#define RETRO_ENVIRONMENT_GET_MESSAGE_INTERFACE_VERSION 59
1295 /* unsigned * --
1296 * Unsigned value is the API version number of the message
1297 * interface supported by the frontend. If callback returns
1298 * false, API version is assumed to be 0.
1299 *
1300 * In legacy code, messages may be displayed in an
1301 * implementation-specific manner by passing a struct
1302 * of type retro_message to RETRO_ENVIRONMENT_SET_MESSAGE.
1303 * This may be still be done regardless of the message
1304 * interface version.
1305 *
1306 * If version is >= 1 however, messages may instead be
1307 * displayed by passing a struct of type retro_message_ext
1308 * to RETRO_ENVIRONMENT_SET_MESSAGE_EXT. This allows the
1309 * core to specify message logging level, priority and
1310 * destination (OSD, logging interface or both).
1311 */
1312
1313#define RETRO_ENVIRONMENT_SET_MESSAGE_EXT 60
1314 /* const struct retro_message_ext * --
1315 * Sets a message to be displayed in an implementation-specific
1316 * manner for a certain amount of 'frames'. Additionally allows
1317 * the core to specify message logging level, priority and
1318 * destination (OSD, logging interface or both).
1319 * Should not be used for trivial messages, which should simply be
1320 * logged via RETRO_ENVIRONMENT_GET_LOG_INTERFACE (or as a
1321 * fallback, stderr).
1322 */
1323
1324#define RETRO_ENVIRONMENT_GET_INPUT_MAX_USERS 61
1325 /* unsigned * --
1326 * Unsigned value is the number of active input devices
1327 * provided by the frontend. This may change between
1328 * frames, but will remain constant for the duration
1329 * of each frame.
1330 * If callback returns true, a core need not poll any
1331 * input device with an index greater than or equal to
1332 * the number of active devices.
1333 * If callback returns false, the number of active input
1334 * devices is unknown. In this case, all input devices
1335 * should be considered active.
1336 */
1337
1338#define RETRO_ENVIRONMENT_SET_AUDIO_BUFFER_STATUS_CALLBACK 62
1339 /* const struct retro_audio_buffer_status_callback * --
1340 * Lets the core know the occupancy level of the frontend
1341 * audio buffer. Can be used by a core to attempt frame
1342 * skipping in order to avoid buffer under-runs.
1343 * A core may pass NULL to disable buffer status reporting
1344 * in the frontend.
1345 */
1346
1347#define RETRO_ENVIRONMENT_SET_MINIMUM_AUDIO_LATENCY 63
1348 /* const unsigned * --
1349 * Sets minimum frontend audio latency in milliseconds.
1350 * Resultant audio latency may be larger than set value,
1351 * or smaller if a hardware limit is encountered. A frontend
1352 * is expected to honour requests up to 512 ms.
1353 *
1354 * - If value is less than current frontend
1355 * audio latency, callback has no effect
1356 * - If value is zero, default frontend audio
1357 * latency is set
1358 *
1359 * May be used by a core to increase audio latency and
1360 * therefore decrease the probability of buffer under-runs
1361 * (crackling) when performing 'intensive' operations.
1362 * A core utilising RETRO_ENVIRONMENT_SET_AUDIO_BUFFER_STATUS_CALLBACK
1363 * to implement audio-buffer-based frame skipping may achieve
1364 * optimal results by setting the audio latency to a 'high'
1365 * (typically 6x or 8x) integer multiple of the expected
1366 * frame time.
1367 *
1368 * WARNING: This can only be called from within retro_run().
1369 * Calling this can require a full reinitialization of audio
1370 * drivers in the frontend, so it is important to call it very
1371 * sparingly, and usually only with the users explicit consent.
1372 * An eventual driver reinitialize will happen so that audio
1373 * callbacks happening after this call within the same retro_run()
1374 * call will target the newly initialized driver.
1375 */
1376
1377/* VFS functionality */
1378
1379/* File paths:
1380 * File paths passed as parameters when using this API shall be well formed UNIX-style,
1381 * using "/" (unquoted forward slash) as directory separator regardless of the platform's native separator.
1382 * Paths shall also include at least one forward slash ("game.bin" is an invalid path, use "./game.bin" instead).
1383 * Other than the directory separator, cores shall not make assumptions about path format:
1384 * "C:/path/game.bin", "http://example.com/game.bin", "#game/game.bin", "./game.bin" (without quotes) are all valid paths.
1385 * Cores may replace the basename or remove path components from the end, and/or add new components;
1386 * however, cores shall not append "./", "../" or multiple consecutive forward slashes ("//") to paths they request to front end.
1387 * The frontend is encouraged to make such paths work as well as it can, but is allowed to give up if the core alters paths too much.
1388 * Frontends are encouraged, but not required, to support native file system paths (modulo replacing the directory separator, if applicable).
1389 * Cores are allowed to try using them, but must remain functional if the front rejects such requests.
1390 * Cores are encouraged to use the libretro-common filestream functions for file I/O,
1391 * as they seamlessly integrate with VFS, deal with directory separator replacement as appropriate
1392 * and provide platform-specific fallbacks in cases where front ends do not support VFS. */
1393
1394/* Opaque file handle
1395 * Introduced in VFS API v1 */
1396struct retro_vfs_file_handle;
1397
1398/* Opaque directory handle
1399 * Introduced in VFS API v3 */
1400struct retro_vfs_dir_handle;
1401
1402/* File open flags
1403 * Introduced in VFS API v1 */
1404#define RETRO_VFS_FILE_ACCESS_READ (1 << 0) /* Read only mode */
1405#define RETRO_VFS_FILE_ACCESS_WRITE (1 << 1) /* Write only mode, discard contents and overwrites existing file unless RETRO_VFS_FILE_ACCESS_UPDATE is also specified */
1406#define RETRO_VFS_FILE_ACCESS_READ_WRITE (RETRO_VFS_FILE_ACCESS_READ | RETRO_VFS_FILE_ACCESS_WRITE) /* Read-write mode, discard contents and overwrites existing file unless RETRO_VFS_FILE_ACCESS_UPDATE is also specified*/
1407#define RETRO_VFS_FILE_ACCESS_UPDATE_EXISTING (1 << 2) /* Prevents discarding content of existing files opened for writing */
1408
1409/* These are only hints. The frontend may choose to ignore them. Other than RAM/CPU/etc use,
1410 and how they react to unlikely external interference (for example someone else writing to that file,
1411 or the file's server going down), behavior will not change. */
1412#define RETRO_VFS_FILE_ACCESS_HINT_NONE (0)
1413/* Indicate that the file will be accessed many times. The frontend should aggressively cache everything. */
1414#define RETRO_VFS_FILE_ACCESS_HINT_FREQUENT_ACCESS (1 << 0)
1415
1416/* Seek positions */
1417#define RETRO_VFS_SEEK_POSITION_START 0
1418#define RETRO_VFS_SEEK_POSITION_CURRENT 1
1419#define RETRO_VFS_SEEK_POSITION_END 2
1420
1421/* stat() result flags
1422 * Introduced in VFS API v3 */
1423#define RETRO_VFS_STAT_IS_VALID (1 << 0)
1424#define RETRO_VFS_STAT_IS_DIRECTORY (1 << 1)
1425#define RETRO_VFS_STAT_IS_CHARACTER_SPECIAL (1 << 2)
1426
1427/* Get path from opaque handle. Returns the exact same path passed to file_open when getting the handle
1428 * Introduced in VFS API v1 */
1429typedef const char *(RETRO_CALLCONV *retro_vfs_get_path_t)(struct retro_vfs_file_handle *stream);
1430
1431/* Open a file for reading or writing. If path points to a directory, this will
1432 * fail. Returns the opaque file handle, or NULL for error.
1433 * Introduced in VFS API v1 */
1434typedef struct retro_vfs_file_handle *(RETRO_CALLCONV *retro_vfs_open_t)(const char *path, unsigned mode, unsigned hints);
1435
1436/* Close the file and release its resources. Must be called if open_file returns non-NULL. Returns 0 on success, -1 on failure.
1437 * Whether the call succeeds ot not, the handle passed as parameter becomes invalid and should no longer be used.
1438 * Introduced in VFS API v1 */
1439typedef int (RETRO_CALLCONV *retro_vfs_close_t)(struct retro_vfs_file_handle *stream);
1440
1441/* Return the size of the file in bytes, or -1 for error.
1442 * Introduced in VFS API v1 */
1443typedef int64_t (RETRO_CALLCONV *retro_vfs_size_t)(struct retro_vfs_file_handle *stream);
1444
1445/* Truncate file to specified size. Returns 0 on success or -1 on error
1446 * Introduced in VFS API v2 */
1447typedef int64_t (RETRO_CALLCONV *retro_vfs_truncate_t)(struct retro_vfs_file_handle *stream, int64_t length);
1448
1449/* Get the current read / write position for the file. Returns -1 for error.
1450 * Introduced in VFS API v1 */
1451typedef int64_t (RETRO_CALLCONV *retro_vfs_tell_t)(struct retro_vfs_file_handle *stream);
1452
1453/* Set the current read/write position for the file. Returns the new position, -1 for error.
1454 * Introduced in VFS API v1 */
1455typedef int64_t (RETRO_CALLCONV *retro_vfs_seek_t)(struct retro_vfs_file_handle *stream, int64_t offset, int seek_position);
1456
1457/* Read data from a file. Returns the number of bytes read, or -1 for error.
1458 * Introduced in VFS API v1 */
1459typedef int64_t (RETRO_CALLCONV *retro_vfs_read_t)(struct retro_vfs_file_handle *stream, void *s, uint64_t len);
1460
1461/* Write data to a file. Returns the number of bytes written, or -1 for error.
1462 * Introduced in VFS API v1 */
1463typedef int64_t (RETRO_CALLCONV *retro_vfs_write_t)(struct retro_vfs_file_handle *stream, const void *s, uint64_t len);
1464
1465/* Flush pending writes to file, if using buffered IO. Returns 0 on sucess, or -1 on failure.
1466 * Introduced in VFS API v1 */
1467typedef int (RETRO_CALLCONV *retro_vfs_flush_t)(struct retro_vfs_file_handle *stream);
1468
1469/* Delete the specified file. Returns 0 on success, -1 on failure
1470 * Introduced in VFS API v1 */
1471typedef int (RETRO_CALLCONV *retro_vfs_remove_t)(const char *path);
1472
1473/* Rename the specified file. Returns 0 on success, -1 on failure
1474 * Introduced in VFS API v1 */
1475typedef int (RETRO_CALLCONV *retro_vfs_rename_t)(const char *old_path, const char *new_path);
1476
1477/* Stat the specified file. Retruns a bitmask of RETRO_VFS_STAT_* flags, none are set if path was not valid.
1478 * Additionally stores file size in given variable, unless NULL is given.
1479 * Introduced in VFS API v3 */
1480typedef int (RETRO_CALLCONV *retro_vfs_stat_t)(const char *path, int32_t *size);
1481
1482/* Create the specified directory. Returns 0 on success, -1 on unknown failure, -2 if already exists.
1483 * Introduced in VFS API v3 */
1484typedef int (RETRO_CALLCONV *retro_vfs_mkdir_t)(const char *dir);
1485
1486/* Open the specified directory for listing. Returns the opaque dir handle, or NULL for error.
1487 * Support for the include_hidden argument may vary depending on the platform.
1488 * Introduced in VFS API v3 */
1489typedef struct retro_vfs_dir_handle *(RETRO_CALLCONV *retro_vfs_opendir_t)(const char *dir, bool include_hidden);
1490
1491/* Read the directory entry at the current position, and move the read pointer to the next position.
1492 * Returns true on success, false if already on the last entry.
1493 * Introduced in VFS API v3 */
1494typedef bool (RETRO_CALLCONV *retro_vfs_readdir_t)(struct retro_vfs_dir_handle *dirstream);
1495
1496/* Get the name of the last entry read. Returns a string on success, or NULL for error.
1497 * The returned string pointer is valid until the next call to readdir or closedir.
1498 * Introduced in VFS API v3 */
1499typedef const char *(RETRO_CALLCONV *retro_vfs_dirent_get_name_t)(struct retro_vfs_dir_handle *dirstream);
1500
1501/* Check if the last entry read was a directory. Returns true if it was, false otherwise (or on error).
1502 * Introduced in VFS API v3 */
1503typedef bool (RETRO_CALLCONV *retro_vfs_dirent_is_dir_t)(struct retro_vfs_dir_handle *dirstream);
1504
1505/* Close the directory and release its resources. Must be called if opendir returns non-NULL. Returns 0 on success, -1 on failure.
1506 * Whether the call succeeds ot not, the handle passed as parameter becomes invalid and should no longer be used.
1507 * Introduced in VFS API v3 */
1508typedef int (RETRO_CALLCONV *retro_vfs_closedir_t)(struct retro_vfs_dir_handle *dirstream);
1509
1510struct retro_vfs_interface
1511{
1512 /* VFS API v1 */
1513 retro_vfs_get_path_t get_path;
1514 retro_vfs_open_t open;
1515 retro_vfs_close_t close;
1516 retro_vfs_size_t size;
1517 retro_vfs_tell_t tell;
1518 retro_vfs_seek_t seek;
1519 retro_vfs_read_t read;
1520 retro_vfs_write_t write;
1521 retro_vfs_flush_t flush;
1522 retro_vfs_remove_t remove;
1523 retro_vfs_rename_t rename;
1524 /* VFS API v2 */
1525 retro_vfs_truncate_t truncate;
1526 /* VFS API v3 */
1527 retro_vfs_stat_t stat;
1528 retro_vfs_mkdir_t mkdir;
1529 retro_vfs_opendir_t opendir;
1530 retro_vfs_readdir_t readdir;
1531 retro_vfs_dirent_get_name_t dirent_get_name;
1532 retro_vfs_dirent_is_dir_t dirent_is_dir;
1533 retro_vfs_closedir_t closedir;
1534};
1535
1536struct retro_vfs_interface_info
1537{
1538 /* Set by core: should this be higher than the version the front end supports,
1539 * front end will return false in the RETRO_ENVIRONMENT_GET_VFS_INTERFACE call
1540 * Introduced in VFS API v1 */
1541 uint32_t required_interface_version;
1542
1543 /* Frontend writes interface pointer here. The frontend also sets the actual
1544 * version, must be at least required_interface_version.
1545 * Introduced in VFS API v1 */
1546 struct retro_vfs_interface *iface;
1547};
1548
1549enum retro_hw_render_interface_type
1550{
1551 RETRO_HW_RENDER_INTERFACE_VULKAN = 0,
1552 RETRO_HW_RENDER_INTERFACE_D3D9 = 1,
1553 RETRO_HW_RENDER_INTERFACE_D3D10 = 2,
1554 RETRO_HW_RENDER_INTERFACE_D3D11 = 3,
1555 RETRO_HW_RENDER_INTERFACE_D3D12 = 4,
1556 RETRO_HW_RENDER_INTERFACE_GSKIT_PS2 = 5,
1557 RETRO_HW_RENDER_INTERFACE_DUMMY = INT_MAX
1558};
1559
1560/* Base struct. All retro_hw_render_interface_* types
1561 * contain at least these fields. */
1562struct retro_hw_render_interface
1563{
1564 enum retro_hw_render_interface_type interface_type;
1565 unsigned interface_version;
1566};
1567
1568typedef void (RETRO_CALLCONV *retro_set_led_state_t)(int led, int state);
1569struct retro_led_interface
1570{
1571 retro_set_led_state_t set_led_state;
1572};
1573
1574/* Retrieves the current state of the MIDI input.
1575 * Returns true if it's enabled, false otherwise. */
1576typedef bool (RETRO_CALLCONV *retro_midi_input_enabled_t)(void);
1577
1578/* Retrieves the current state of the MIDI output.
1579 * Returns true if it's enabled, false otherwise */
1580typedef bool (RETRO_CALLCONV *retro_midi_output_enabled_t)(void);
1581
1582/* Reads next byte from the input stream.
1583 * Returns true if byte is read, false otherwise. */
1584typedef bool (RETRO_CALLCONV *retro_midi_read_t)(uint8_t *byte);
1585
1586/* Writes byte to the output stream.
1587 * 'delta_time' is in microseconds and represent time elapsed since previous write.
1588 * Returns true if byte is written, false otherwise. */
1589typedef bool (RETRO_CALLCONV *retro_midi_write_t)(uint8_t byte, uint32_t delta_time);
1590
1591/* Flushes previously written data.
1592 * Returns true if successful, false otherwise. */
1593typedef bool (RETRO_CALLCONV *retro_midi_flush_t)(void);
1594
1595struct retro_midi_interface
1596{
1597 retro_midi_input_enabled_t input_enabled;
1598 retro_midi_output_enabled_t output_enabled;
1599 retro_midi_read_t read;
1600 retro_midi_write_t write;
1601 retro_midi_flush_t flush;
1602};
1603
1604enum retro_hw_render_context_negotiation_interface_type
1605{
1606 RETRO_HW_RENDER_CONTEXT_NEGOTIATION_INTERFACE_VULKAN = 0,
1607 RETRO_HW_RENDER_CONTEXT_NEGOTIATION_INTERFACE_DUMMY = INT_MAX
1608};
1609
1610/* Base struct. All retro_hw_render_context_negotiation_interface_* types
1611 * contain at least these fields. */
1612struct retro_hw_render_context_negotiation_interface
1613{
1614 enum retro_hw_render_context_negotiation_interface_type interface_type;
1615 unsigned interface_version;
1616};
1617
1618/* Serialized state is incomplete in some way. Set if serialization is
1619 * usable in typical end-user cases but should not be relied upon to
1620 * implement frame-sensitive frontend features such as netplay or
1621 * rerecording. */
1622#define RETRO_SERIALIZATION_QUIRK_INCOMPLETE (1 << 0)
1623/* The core must spend some time initializing before serialization is
1624 * supported. retro_serialize() will initially fail; retro_unserialize()
1625 * and retro_serialize_size() may or may not work correctly either. */
1626#define RETRO_SERIALIZATION_QUIRK_MUST_INITIALIZE (1 << 1)
1627/* Serialization size may change within a session. */
1628#define RETRO_SERIALIZATION_QUIRK_CORE_VARIABLE_SIZE (1 << 2)
1629/* Set by the frontend to acknowledge that it supports variable-sized
1630 * states. */
1631#define RETRO_SERIALIZATION_QUIRK_FRONT_VARIABLE_SIZE (1 << 3)
1632/* Serialized state can only be loaded during the same session. */
1633#define RETRO_SERIALIZATION_QUIRK_SINGLE_SESSION (1 << 4)
1634/* Serialized state cannot be loaded on an architecture with a different
1635 * endianness from the one it was saved on. */
1636#define RETRO_SERIALIZATION_QUIRK_ENDIAN_DEPENDENT (1 << 5)
1637/* Serialized state cannot be loaded on a different platform from the one it
1638 * was saved on for reasons other than endianness, such as word size
1639 * dependence */
1640#define RETRO_SERIALIZATION_QUIRK_PLATFORM_DEPENDENT (1 << 6)
1641
1642#define RETRO_MEMDESC_CONST (1 << 0) /* The frontend will never change this memory area once retro_load_game has returned. */
1643#define RETRO_MEMDESC_BIGENDIAN (1 << 1) /* The memory area contains big endian data. Default is little endian. */
1644#define RETRO_MEMDESC_SYSTEM_RAM (1 << 2) /* The memory area is system RAM. This is main RAM of the gaming system. */
1645#define RETRO_MEMDESC_SAVE_RAM (1 << 3) /* The memory area is save RAM. This RAM is usually found on a game cartridge, backed up by a battery. */
1646#define RETRO_MEMDESC_VIDEO_RAM (1 << 4) /* The memory area is video RAM (VRAM) */
1647#define RETRO_MEMDESC_ALIGN_2 (1 << 16) /* All memory access in this area is aligned to their own size, or 2, whichever is smaller. */
1648#define RETRO_MEMDESC_ALIGN_4 (2 << 16)
1649#define RETRO_MEMDESC_ALIGN_8 (3 << 16)
1650#define RETRO_MEMDESC_MINSIZE_2 (1 << 24) /* All memory in this region is accessed at least 2 bytes at the time. */
1651#define RETRO_MEMDESC_MINSIZE_4 (2 << 24)
1652#define RETRO_MEMDESC_MINSIZE_8 (3 << 24)
1653struct retro_memory_descriptor
1654{
1655 uint64_t flags;
1656
1657 /* Pointer to the start of the relevant ROM or RAM chip.
1658 * It's strongly recommended to use 'offset' if possible, rather than
1659 * doing math on the pointer.
1660 *
1661 * If the same byte is mapped my multiple descriptors, their descriptors
1662 * must have the same pointer.
1663 * If 'start' does not point to the first byte in the pointer, put the
1664 * difference in 'offset' instead.
1665 *
1666 * May be NULL if there's nothing usable here (e.g. hardware registers and
1667 * open bus). No flags should be set if the pointer is NULL.
1668 * It's recommended to minimize the number of descriptors if possible,
1669 * but not mandatory. */
1670 void *ptr;
1671 size_t offset;
1672
1673 /* This is the location in the emulated address space
1674 * where the mapping starts. */
1675 size_t start;
1676
1677 /* Which bits must be same as in 'start' for this mapping to apply.
1678 * The first memory descriptor to claim a certain byte is the one
1679 * that applies.
1680 * A bit which is set in 'start' must also be set in this.
1681 * Can be zero, in which case each byte is assumed mapped exactly once.
1682 * In this case, 'len' must be a power of two. */
1683 size_t select;
1684
1685 /* If this is nonzero, the set bits are assumed not connected to the
1686 * memory chip's address pins. */
1687 size_t disconnect;
1688
1689 /* This one tells the size of the current memory area.
1690 * If, after start+disconnect are applied, the address is higher than
1691 * this, the highest bit of the address is cleared.
1692 *
1693 * If the address is still too high, the next highest bit is cleared.
1694 * Can be zero, in which case it's assumed to be infinite (as limited
1695 * by 'select' and 'disconnect'). */
1696 size_t len;
1697
1698 /* To go from emulated address to physical address, the following
1699 * order applies:
1700 * Subtract 'start', pick off 'disconnect', apply 'len', add 'offset'. */
1701
1702 /* The address space name must consist of only a-zA-Z0-9_-,
1703 * should be as short as feasible (maximum length is 8 plus the NUL),
1704 * and may not be any other address space plus one or more 0-9A-F
1705 * at the end.
1706 * However, multiple memory descriptors for the same address space is
1707 * allowed, and the address space name can be empty. NULL is treated
1708 * as empty.
1709 *
1710 * Address space names are case sensitive, but avoid lowercase if possible.
1711 * The same pointer may exist in multiple address spaces.
1712 *
1713 * Examples:
1714 * blank+blank - valid (multiple things may be mapped in the same namespace)
1715 * 'Sp'+'Sp' - valid (multiple things may be mapped in the same namespace)
1716 * 'A'+'B' - valid (neither is a prefix of each other)
1717 * 'S'+blank - valid ('S' is not in 0-9A-F)
1718 * 'a'+blank - valid ('a' is not in 0-9A-F)
1719 * 'a'+'A' - valid (neither is a prefix of each other)
1720 * 'AR'+blank - valid ('R' is not in 0-9A-F)
1721 * 'ARB'+blank - valid (the B can't be part of the address either, because
1722 * there is no namespace 'AR')
1723 * blank+'B' - not valid, because it's ambigous which address space B1234
1724 * would refer to.
1725 * The length can't be used for that purpose; the frontend may want
1726 * to append arbitrary data to an address, without a separator. */
1727 const char *addrspace;
1728
1729 /* TODO: When finalizing this one, add a description field, which should be
1730 * "WRAM" or something roughly equally long. */
1731
1732 /* TODO: When finalizing this one, replace 'select' with 'limit', which tells
1733 * which bits can vary and still refer to the same address (limit = ~select).
1734 * TODO: limit? range? vary? something else? */
1735
1736 /* TODO: When finalizing this one, if 'len' is above what 'select' (or
1737 * 'limit') allows, it's bankswitched. Bankswitched data must have both 'len'
1738 * and 'select' != 0, and the mappings don't tell how the system switches the
1739 * banks. */
1740
1741 /* TODO: When finalizing this one, fix the 'len' bit removal order.
1742 * For len=0x1800, pointer 0x1C00 should go to 0x1400, not 0x0C00.
1743 * Algorithm: Take bits highest to lowest, but if it goes above len, clear
1744 * the most recent addition and continue on the next bit.
1745 * TODO: Can the above be optimized? Is "remove the lowest bit set in both
1746 * pointer and 'len'" equivalent? */
1747
1748 /* TODO: Some emulators (MAME?) emulate big endian systems by only accessing
1749 * the emulated memory in 32-bit chunks, native endian. But that's nothing
1750 * compared to Darek Mihocka <http://www.emulators.com/docs/nx07_vm101.htm>
1751 * (section Emulation 103 - Nearly Free Byte Reversal) - he flips the ENTIRE
1752 * RAM backwards! I'll want to represent both of those, via some flags.
1753 *
1754 * I suspect MAME either didn't think of that idea, or don't want the #ifdef.
1755 * Not sure which, nor do I really care. */
1756
1757 /* TODO: Some of those flags are unused and/or don't really make sense. Clean
1758 * them up. */
1759};
1760
1761/* The frontend may use the largest value of 'start'+'select' in a
1762 * certain namespace to infer the size of the address space.
1763 *
1764 * If the address space is larger than that, a mapping with .ptr=NULL
1765 * should be at the end of the array, with .select set to all ones for
1766 * as long as the address space is big.
1767 *
1768 * Sample descriptors (minus .ptr, and RETRO_MEMFLAG_ on the flags):
1769 * SNES WRAM:
1770 * .start=0x7E0000, .len=0x20000
1771 * (Note that this must be mapped before the ROM in most cases; some of the
1772 * ROM mappers
1773 * try to claim $7E0000, or at least $7E8000.)
1774 * SNES SPC700 RAM:
1775 * .addrspace="S", .len=0x10000
1776 * SNES WRAM mirrors:
1777 * .flags=MIRROR, .start=0x000000, .select=0xC0E000, .len=0x2000
1778 * .flags=MIRROR, .start=0x800000, .select=0xC0E000, .len=0x2000
1779 * SNES WRAM mirrors, alternate equivalent descriptor:
1780 * .flags=MIRROR, .select=0x40E000, .disconnect=~0x1FFF
1781 * (Various similar constructions can be created by combining parts of
1782 * the above two.)
1783 * SNES LoROM (512KB, mirrored a couple of times):
1784 * .flags=CONST, .start=0x008000, .select=0x408000, .disconnect=0x8000, .len=512*1024
1785 * .flags=CONST, .start=0x400000, .select=0x400000, .disconnect=0x8000, .len=512*1024
1786 * SNES HiROM (4MB):
1787 * .flags=CONST, .start=0x400000, .select=0x400000, .len=4*1024*1024
1788 * .flags=CONST, .offset=0x8000, .start=0x008000, .select=0x408000, .len=4*1024*1024
1789 * SNES ExHiROM (8MB):
1790 * .flags=CONST, .offset=0, .start=0xC00000, .select=0xC00000, .len=4*1024*1024
1791 * .flags=CONST, .offset=4*1024*1024, .start=0x400000, .select=0xC00000, .len=4*1024*1024
1792 * .flags=CONST, .offset=0x8000, .start=0x808000, .select=0xC08000, .len=4*1024*1024
1793 * .flags=CONST, .offset=4*1024*1024+0x8000, .start=0x008000, .select=0xC08000, .len=4*1024*1024
1794 * Clarify the size of the address space:
1795 * .ptr=NULL, .select=0xFFFFFF
1796 * .len can be implied by .select in many of them, but was included for clarity.
1797 */
1798
1799struct retro_memory_map
1800{
1801 const struct retro_memory_descriptor *descriptors;
1802 unsigned num_descriptors;
1803};
1804
1805struct retro_controller_description
1806{
1807 /* Human-readable description of the controller. Even if using a generic
1808 * input device type, this can be set to the particular device type the
1809 * core uses. */
1810 const char *desc;
1811
1812 /* Device type passed to retro_set_controller_port_device(). If the device
1813 * type is a sub-class of a generic input device type, use the
1814 * RETRO_DEVICE_SUBCLASS macro to create an ID.
1815 *
1816 * E.g. RETRO_DEVICE_SUBCLASS(RETRO_DEVICE_JOYPAD, 1). */
1817 unsigned id;
1818};
1819
1820struct retro_controller_info
1821{
1822 const struct retro_controller_description *types;
1823 unsigned num_types;
1824};
1825
1826struct retro_subsystem_memory_info
1827{
1828 /* The extension associated with a memory type, e.g. "psram". */
1829 const char *extension;
1830
1831 /* The memory type for retro_get_memory(). This should be at
1832 * least 0x100 to avoid conflict with standardized
1833 * libretro memory types. */
1834 unsigned type;
1835};
1836
1837struct retro_subsystem_rom_info
1838{
1839 /* Describes what the content is (SGB BIOS, GB ROM, etc). */
1840 const char *desc;
1841
1842 /* Same definition as retro_get_system_info(). */
1843 const char *valid_extensions;
1844
1845 /* Same definition as retro_get_system_info(). */
1846 bool need_fullpath;
1847
1848 /* Same definition as retro_get_system_info(). */
1849 bool block_extract;
1850
1851 /* This is set if the content is required to load a game.
1852 * If this is set to false, a zeroed-out retro_game_info can be passed. */
1853 bool required;
1854
1855 /* Content can have multiple associated persistent
1856 * memory types (retro_get_memory()). */
1857 const struct retro_subsystem_memory_info *memory;
1858 unsigned num_memory;
1859};
1860
1861struct retro_subsystem_info
1862{
1863 /* Human-readable string of the subsystem type, e.g. "Super GameBoy" */
1864 const char *desc;
1865
1866 /* A computer friendly short string identifier for the subsystem type.
1867 * This name must be [a-z].
1868 * E.g. if desc is "Super GameBoy", this can be "sgb".
1869 * This identifier can be used for command-line interfaces, etc.
1870 */
1871 const char *ident;
1872
1873 /* Infos for each content file. The first entry is assumed to be the
1874 * "most significant" content for frontend purposes.
1875 * E.g. with Super GameBoy, the first content should be the GameBoy ROM,
1876 * as it is the most "significant" content to a user.
1877 * If a frontend creates new file paths based on the content used
1878 * (e.g. savestates), it should use the path for the first ROM to do so. */
1879 const struct retro_subsystem_rom_info *roms;
1880
1881 /* Number of content files associated with a subsystem. */
1882 unsigned num_roms;
1883
1884 /* The type passed to retro_load_game_special(). */
1885 unsigned id;
1886};
1887
1888typedef void (RETRO_CALLCONV *retro_proc_address_t)(void);
1889
1890/* libretro API extension functions:
1891 * (None here so far).
1892 *
1893 * Get a symbol from a libretro core.
1894 * Cores should only return symbols which are actual
1895 * extensions to the libretro API.
1896 *
1897 * Frontends should not use this to obtain symbols to standard
1898 * libretro entry points (static linking or dlsym).
1899 *
1900 * The symbol name must be equal to the function name,
1901 * e.g. if void retro_foo(void); exists, the symbol must be called "retro_foo".
1902 * The returned function pointer must be cast to the corresponding type.
1903 */
1904typedef retro_proc_address_t (RETRO_CALLCONV *retro_get_proc_address_t)(const char *sym);
1905
1906struct retro_get_proc_address_interface
1907{
1908 retro_get_proc_address_t get_proc_address;
1909};
1910
1911enum retro_log_level
1912{
1913 RETRO_LOG_DEBUG = 0,
1914 RETRO_LOG_INFO,
1915 RETRO_LOG_WARN,
1916 RETRO_LOG_ERROR,
1917
1918 RETRO_LOG_DUMMY = INT_MAX
1919};
1920
1921/* Logging function. Takes log level argument as well. */
1922typedef void (RETRO_CALLCONV *retro_log_printf_t)(enum retro_log_level level,
1923 const char *fmt, ...);
1924
1925struct retro_log_callback
1926{
1927 retro_log_printf_t log;
1928};
1929
1930/* Performance related functions */
1931
1932/* ID values for SIMD CPU features */
1933#define RETRO_SIMD_SSE (1 << 0)
1934#define RETRO_SIMD_SSE2 (1 << 1)
1935#define RETRO_SIMD_VMX (1 << 2)
1936#define RETRO_SIMD_VMX128 (1 << 3)
1937#define RETRO_SIMD_AVX (1 << 4)
1938#define RETRO_SIMD_NEON (1 << 5)
1939#define RETRO_SIMD_SSE3 (1 << 6)
1940#define RETRO_SIMD_SSSE3 (1 << 7)
1941#define RETRO_SIMD_MMX (1 << 8)
1942#define RETRO_SIMD_MMXEXT (1 << 9)
1943#define RETRO_SIMD_SSE4 (1 << 10)
1944#define RETRO_SIMD_SSE42 (1 << 11)
1945#define RETRO_SIMD_AVX2 (1 << 12)
1946#define RETRO_SIMD_VFPU (1 << 13)
1947#define RETRO_SIMD_PS (1 << 14)
1948#define RETRO_SIMD_AES (1 << 15)
1949#define RETRO_SIMD_VFPV3 (1 << 16)
1950#define RETRO_SIMD_VFPV4 (1 << 17)
1951#define RETRO_SIMD_POPCNT (1 << 18)
1952#define RETRO_SIMD_MOVBE (1 << 19)
1953#define RETRO_SIMD_CMOV (1 << 20)
1954#define RETRO_SIMD_ASIMD (1 << 21)
1955
1956typedef uint64_t retro_perf_tick_t;
1957typedef int64_t retro_time_t;
1958
1959struct retro_perf_counter
1960{
1961 const char *ident;
1962 retro_perf_tick_t start;
1963 retro_perf_tick_t total;
1964 retro_perf_tick_t call_cnt;
1965
1966 bool registered;
1967};
1968
1969/* Returns current time in microseconds.
1970 * Tries to use the most accurate timer available.
1971 */
1972typedef retro_time_t (RETRO_CALLCONV *retro_perf_get_time_usec_t)(void);
1973
1974/* A simple counter. Usually nanoseconds, but can also be CPU cycles.
1975 * Can be used directly if desired (when creating a more sophisticated
1976 * performance counter system).
1977 * */
1978typedef retro_perf_tick_t (RETRO_CALLCONV *retro_perf_get_counter_t)(void);
1979
1980/* Returns a bit-mask of detected CPU features (RETRO_SIMD_*). */
1981typedef uint64_t (RETRO_CALLCONV *retro_get_cpu_features_t)(void);
1982
1983/* Asks frontend to log and/or display the state of performance counters.
1984 * Performance counters can always be poked into manually as well.
1985 */
1986typedef void (RETRO_CALLCONV *retro_perf_log_t)(void);
1987
1988/* Register a performance counter.
1989 * ident field must be set with a discrete value and other values in
1990 * retro_perf_counter must be 0.
1991 * Registering can be called multiple times. To avoid calling to
1992 * frontend redundantly, you can check registered field first. */
1993typedef void (RETRO_CALLCONV *retro_perf_register_t)(struct retro_perf_counter *counter);
1994
1995/* Starts a registered counter. */
1996typedef void (RETRO_CALLCONV *retro_perf_start_t)(struct retro_perf_counter *counter);
1997
1998/* Stops a registered counter. */
1999typedef void (RETRO_CALLCONV *retro_perf_stop_t)(struct retro_perf_counter *counter);
2000
2001/* For convenience it can be useful to wrap register, start and stop in macros.
2002 * E.g.:
2003 * #ifdef LOG_PERFORMANCE
2004 * #define RETRO_PERFORMANCE_INIT(perf_cb, name) static struct retro_perf_counter name = {#name}; if (!name.registered) perf_cb.perf_register(&(name))
2005 * #define RETRO_PERFORMANCE_START(perf_cb, name) perf_cb.perf_start(&(name))
2006 * #define RETRO_PERFORMANCE_STOP(perf_cb, name) perf_cb.perf_stop(&(name))
2007 * #else
2008 * ... Blank macros ...
2009 * #endif
2010 *
2011 * These can then be used mid-functions around code snippets.
2012 *
2013 * extern struct retro_perf_callback perf_cb; * Somewhere in the core.
2014 *
2015 * void do_some_heavy_work(void)
2016 * {
2017 * RETRO_PERFORMANCE_INIT(cb, work_1;
2018 * RETRO_PERFORMANCE_START(cb, work_1);
2019 * heavy_work_1();
2020 * RETRO_PERFORMANCE_STOP(cb, work_1);
2021 *
2022 * RETRO_PERFORMANCE_INIT(cb, work_2);
2023 * RETRO_PERFORMANCE_START(cb, work_2);
2024 * heavy_work_2();
2025 * RETRO_PERFORMANCE_STOP(cb, work_2);
2026 * }
2027 *
2028 * void retro_deinit(void)
2029 * {
2030 * perf_cb.perf_log(); * Log all perf counters here for example.
2031 * }
2032 */
2033
2034struct retro_perf_callback
2035{
2036 retro_perf_get_time_usec_t get_time_usec;
2037 retro_get_cpu_features_t get_cpu_features;
2038
2039 retro_perf_get_counter_t get_perf_counter;
2040 retro_perf_register_t perf_register;
2041 retro_perf_start_t perf_start;
2042 retro_perf_stop_t perf_stop;
2043 retro_perf_log_t perf_log;
2044};
2045
2046/* FIXME: Document the sensor API and work out behavior.
2047 * It will be marked as experimental until then.
2048 */
2049enum retro_sensor_action
2050{
2051 RETRO_SENSOR_ACCELEROMETER_ENABLE = 0,
2052 RETRO_SENSOR_ACCELEROMETER_DISABLE,
2053 RETRO_SENSOR_GYROSCOPE_ENABLE,
2054 RETRO_SENSOR_GYROSCOPE_DISABLE,
2055 RETRO_SENSOR_ILLUMINANCE_ENABLE,
2056 RETRO_SENSOR_ILLUMINANCE_DISABLE,
2057
2058 RETRO_SENSOR_DUMMY = INT_MAX
2059};
2060
2061/* Id values for SENSOR types. */
2062#define RETRO_SENSOR_ACCELEROMETER_X 0
2063#define RETRO_SENSOR_ACCELEROMETER_Y 1
2064#define RETRO_SENSOR_ACCELEROMETER_Z 2
2065#define RETRO_SENSOR_GYROSCOPE_X 3
2066#define RETRO_SENSOR_GYROSCOPE_Y 4
2067#define RETRO_SENSOR_GYROSCOPE_Z 5
2068#define RETRO_SENSOR_ILLUMINANCE 6
2069
2070typedef bool (RETRO_CALLCONV *retro_set_sensor_state_t)(unsigned port,
2071 enum retro_sensor_action action, unsigned rate);
2072
2073typedef float (RETRO_CALLCONV *retro_sensor_get_input_t)(unsigned port, unsigned id);
2074
2075struct retro_sensor_interface
2076{
2077 retro_set_sensor_state_t set_sensor_state;
2078 retro_sensor_get_input_t get_sensor_input;
2079};
2080
2081enum retro_camera_buffer
2082{
2083 RETRO_CAMERA_BUFFER_OPENGL_TEXTURE = 0,
2084 RETRO_CAMERA_BUFFER_RAW_FRAMEBUFFER,
2085
2086 RETRO_CAMERA_BUFFER_DUMMY = INT_MAX
2087};
2088
2089/* Starts the camera driver. Can only be called in retro_run(). */
2090typedef bool (RETRO_CALLCONV *retro_camera_start_t)(void);
2091
2092/* Stops the camera driver. Can only be called in retro_run(). */
2093typedef void (RETRO_CALLCONV *retro_camera_stop_t)(void);
2094
2095/* Callback which signals when the camera driver is initialized
2096 * and/or deinitialized.
2097 * retro_camera_start_t can be called in initialized callback.
2098 */
2099typedef void (RETRO_CALLCONV *retro_camera_lifetime_status_t)(void);
2100
2101/* A callback for raw framebuffer data. buffer points to an XRGB8888 buffer.
2102 * Width, height and pitch are similar to retro_video_refresh_t.
2103 * First pixel is top-left origin.
2104 */
2105typedef void (RETRO_CALLCONV *retro_camera_frame_raw_framebuffer_t)(const uint32_t *buffer,
2106 unsigned width, unsigned height, size_t pitch);
2107
2108/* A callback for when OpenGL textures are used.
2109 *
2110 * texture_id is a texture owned by camera driver.
2111 * Its state or content should be considered immutable, except for things like
2112 * texture filtering and clamping.
2113 *
2114 * texture_target is the texture target for the GL texture.
2115 * These can include e.g. GL_TEXTURE_2D, GL_TEXTURE_RECTANGLE, and possibly
2116 * more depending on extensions.
2117 *
2118 * affine points to a packed 3x3 column-major matrix used to apply an affine
2119 * transform to texture coordinates. (affine_matrix * vec3(coord_x, coord_y, 1.0))
2120 * After transform, normalized texture coord (0, 0) should be bottom-left
2121 * and (1, 1) should be top-right (or (width, height) for RECTANGLE).
2122 *
2123 * GL-specific typedefs are avoided here to avoid relying on gl.h in
2124 * the API definition.
2125 */
2126typedef void (RETRO_CALLCONV *retro_camera_frame_opengl_texture_t)(unsigned texture_id,
2127 unsigned texture_target, const float *affine);
2128
2129struct retro_camera_callback
2130{
2131 /* Set by libretro core.
2132 * Example bitmask: caps = (1 << RETRO_CAMERA_BUFFER_OPENGL_TEXTURE) | (1 << RETRO_CAMERA_BUFFER_RAW_FRAMEBUFFER).
2133 */
2134 uint64_t caps;
2135
2136 /* Desired resolution for camera. Is only used as a hint. */
2137 unsigned width;
2138 unsigned height;
2139
2140 /* Set by frontend. */
2141 retro_camera_start_t start;
2142 retro_camera_stop_t stop;
2143
2144 /* Set by libretro core if raw framebuffer callbacks will be used. */
2145 retro_camera_frame_raw_framebuffer_t frame_raw_framebuffer;
2146
2147 /* Set by libretro core if OpenGL texture callbacks will be used. */
2148 retro_camera_frame_opengl_texture_t frame_opengl_texture;
2149
2150 /* Set by libretro core. Called after camera driver is initialized and
2151 * ready to be started.
2152 * Can be NULL, in which this callback is not called.
2153 */
2154 retro_camera_lifetime_status_t initialized;
2155
2156 /* Set by libretro core. Called right before camera driver is
2157 * deinitialized.
2158 * Can be NULL, in which this callback is not called.
2159 */
2160 retro_camera_lifetime_status_t deinitialized;
2161};
2162
2163/* Sets the interval of time and/or distance at which to update/poll
2164 * location-based data.
2165 *
2166 * To ensure compatibility with all location-based implementations,
2167 * values for both interval_ms and interval_distance should be provided.
2168 *
2169 * interval_ms is the interval expressed in milliseconds.
2170 * interval_distance is the distance interval expressed in meters.
2171 */
2172typedef void (RETRO_CALLCONV *retro_location_set_interval_t)(unsigned interval_ms,
2173 unsigned interval_distance);
2174
2175/* Start location services. The device will start listening for changes to the
2176 * current location at regular intervals (which are defined with
2177 * retro_location_set_interval_t). */
2178typedef bool (RETRO_CALLCONV *retro_location_start_t)(void);
2179
2180/* Stop location services. The device will stop listening for changes
2181 * to the current location. */
2182typedef void (RETRO_CALLCONV *retro_location_stop_t)(void);
2183
2184/* Get the position of the current location. Will set parameters to
2185 * 0 if no new location update has happened since the last time. */
2186typedef bool (RETRO_CALLCONV *retro_location_get_position_t)(double *lat, double *lon,
2187 double *horiz_accuracy, double *vert_accuracy);
2188
2189/* Callback which signals when the location driver is initialized
2190 * and/or deinitialized.
2191 * retro_location_start_t can be called in initialized callback.
2192 */
2193typedef void (RETRO_CALLCONV *retro_location_lifetime_status_t)(void);
2194
2195struct retro_location_callback
2196{
2197 retro_location_start_t start;
2198 retro_location_stop_t stop;
2199 retro_location_get_position_t get_position;
2200 retro_location_set_interval_t set_interval;
2201
2202 retro_location_lifetime_status_t initialized;
2203 retro_location_lifetime_status_t deinitialized;
2204};
2205
2206enum retro_rumble_effect
2207{
2208 RETRO_RUMBLE_STRONG = 0,
2209 RETRO_RUMBLE_WEAK = 1,
2210
2211 RETRO_RUMBLE_DUMMY = INT_MAX
2212};
2213
2214/* Sets rumble state for joypad plugged in port 'port'.
2215 * Rumble effects are controlled independently,
2216 * and setting e.g. strong rumble does not override weak rumble.
2217 * Strength has a range of [0, 0xffff].
2218 *
2219 * Returns true if rumble state request was honored.
2220 * Calling this before first retro_run() is likely to return false. */
2221typedef bool (RETRO_CALLCONV *retro_set_rumble_state_t)(unsigned port,
2222 enum retro_rumble_effect effect, uint16_t strength);
2223
2224struct retro_rumble_interface
2225{
2226 retro_set_rumble_state_t set_rumble_state;
2227};
2228
2229/* Notifies libretro that audio data should be written. */
2230typedef void (RETRO_CALLCONV *retro_audio_callback_t)(void);
2231
2232/* True: Audio driver in frontend is active, and callback is
2233 * expected to be called regularily.
2234 * False: Audio driver in frontend is paused or inactive.
2235 * Audio callback will not be called until set_state has been
2236 * called with true.
2237 * Initial state is false (inactive).
2238 */
2239typedef void (RETRO_CALLCONV *retro_audio_set_state_callback_t)(bool enabled);
2240
2241struct retro_audio_callback
2242{
2243 retro_audio_callback_t callback;
2244 retro_audio_set_state_callback_t set_state;
2245};
2246
2247/* Notifies a libretro core of time spent since last invocation
2248 * of retro_run() in microseconds.
2249 *
2250 * It will be called right before retro_run() every frame.
2251 * The frontend can tamper with timing to support cases like
2252 * fast-forward, slow-motion and framestepping.
2253 *
2254 * In those scenarios the reference frame time value will be used. */
2255typedef int64_t retro_usec_t;
2256typedef void (RETRO_CALLCONV *retro_frame_time_callback_t)(retro_usec_t usec);
2257struct retro_frame_time_callback
2258{
2259 retro_frame_time_callback_t callback;
2260 /* Represents the time of one frame. It is computed as
2261 * 1000000 / fps, but the implementation will resolve the
2262 * rounding to ensure that framestepping, etc is exact. */
2263 retro_usec_t reference;
2264};
2265
2266/* Notifies a libretro core of the current occupancy
2267 * level of the frontend audio buffer.
2268 *
2269 * - active: 'true' if audio buffer is currently
2270 * in use. Will be 'false' if audio is
2271 * disabled in the frontend
2272 *
2273 * - occupancy: Given as a value in the range [0,100],
2274 * corresponding to the occupancy percentage
2275 * of the audio buffer
2276 *
2277 * - underrun_likely: 'true' if the frontend expects an
2278 * audio buffer underrun during the
2279 * next frame (indicates that a core
2280 * should attempt frame skipping)
2281 *
2282 * It will be called right before retro_run() every frame. */
2283typedef void (RETRO_CALLCONV *retro_audio_buffer_status_callback_t)(
2284 bool active, unsigned occupancy, bool underrun_likely);
2285struct retro_audio_buffer_status_callback
2286{
2287 retro_audio_buffer_status_callback_t callback;
2288};
2289
2290/* Pass this to retro_video_refresh_t if rendering to hardware.
2291 * Passing NULL to retro_video_refresh_t is still a frame dupe as normal.
2292 * */
2293#define RETRO_HW_FRAME_BUFFER_VALID ((void*)-1)
2294
2295/* Invalidates the current HW context.
2296 * Any GL state is lost, and must not be deinitialized explicitly.
2297 * If explicit deinitialization is desired by the libretro core,
2298 * it should implement context_destroy callback.
2299 * If called, all GPU resources must be reinitialized.
2300 * Usually called when frontend reinits video driver.
2301 * Also called first time video driver is initialized,
2302 * allowing libretro core to initialize resources.
2303 */
2304typedef void (RETRO_CALLCONV *retro_hw_context_reset_t)(void);
2305
2306/* Gets current framebuffer which is to be rendered to.
2307 * Could change every frame potentially.
2308 */
2309typedef uintptr_t (RETRO_CALLCONV *retro_hw_get_current_framebuffer_t)(void);
2310
2311/* Get a symbol from HW context. */
2312typedef retro_proc_address_t (RETRO_CALLCONV *retro_hw_get_proc_address_t)(const char *sym);
2313
2314enum retro_hw_context_type
2315{
2316 RETRO_HW_CONTEXT_NONE = 0,
2317 /* OpenGL 2.x. Driver can choose to use latest compatibility context. */
2318 RETRO_HW_CONTEXT_OPENGL = 1,
2319 /* OpenGL ES 2.0. */
2320 RETRO_HW_CONTEXT_OPENGLES2 = 2,
2321 /* Modern desktop core GL context. Use version_major/
2322 * version_minor fields to set GL version. */
2323 RETRO_HW_CONTEXT_OPENGL_CORE = 3,
2324 /* OpenGL ES 3.0 */
2325 RETRO_HW_CONTEXT_OPENGLES3 = 4,
2326 /* OpenGL ES 3.1+. Set version_major/version_minor. For GLES2 and GLES3,
2327 * use the corresponding enums directly. */
2328 RETRO_HW_CONTEXT_OPENGLES_VERSION = 5,
2329
2330 /* Vulkan, see RETRO_ENVIRONMENT_GET_HW_RENDER_INTERFACE. */
2331 RETRO_HW_CONTEXT_VULKAN = 6,
2332
2333 /* Direct3D, set version_major to select the type of interface
2334 * returned by RETRO_ENVIRONMENT_GET_HW_RENDER_INTERFACE */
2335 RETRO_HW_CONTEXT_DIRECT3D = 7,
2336
2337 RETRO_HW_CONTEXT_DUMMY = INT_MAX
2338};
2339
2340struct retro_hw_render_callback
2341{
2342 /* Which API to use. Set by libretro core. */
2343 enum retro_hw_context_type context_type;
2344
2345 /* Called when a context has been created or when it has been reset.
2346 * An OpenGL context is only valid after context_reset() has been called.
2347 *
2348 * When context_reset is called, OpenGL resources in the libretro
2349 * implementation are guaranteed to be invalid.
2350 *
2351 * It is possible that context_reset is called multiple times during an
2352 * application lifecycle.
2353 * If context_reset is called without any notification (context_destroy),
2354 * the OpenGL context was lost and resources should just be recreated
2355 * without any attempt to "free" old resources.
2356 */
2357 retro_hw_context_reset_t context_reset;
2358
2359 /* Set by frontend.
2360 * TODO: This is rather obsolete. The frontend should not
2361 * be providing preallocated framebuffers. */
2362 retro_hw_get_current_framebuffer_t get_current_framebuffer;
2363
2364 /* Set by frontend.
2365 * Can return all relevant functions, including glClear on Windows. */
2366 retro_hw_get_proc_address_t get_proc_address;
2367
2368 /* Set if render buffers should have depth component attached.
2369 * TODO: Obsolete. */
2370 bool depth;
2371
2372 /* Set if stencil buffers should be attached.
2373 * TODO: Obsolete. */
2374 bool stencil;
2375
2376 /* If depth and stencil are true, a packed 24/8 buffer will be added.
2377 * Only attaching stencil is invalid and will be ignored. */
2378
2379 /* Use conventional bottom-left origin convention. If false,
2380 * standard libretro top-left origin semantics are used.
2381 * TODO: Move to GL specific interface. */
2382 bool bottom_left_origin;
2383
2384 /* Major version number for core GL context or GLES 3.1+. */
2385 unsigned version_major;
2386
2387 /* Minor version number for core GL context or GLES 3.1+. */
2388 unsigned version_minor;
2389
2390 /* If this is true, the frontend will go very far to avoid
2391 * resetting context in scenarios like toggling fullscreen, etc.
2392 * TODO: Obsolete? Maybe frontend should just always assume this ...
2393 */
2394 bool cache_context;
2395
2396 /* The reset callback might still be called in extreme situations
2397 * such as if the context is lost beyond recovery.
2398 *
2399 * For optimal stability, set this to false, and allow context to be
2400 * reset at any time.
2401 */
2402
2403 /* A callback to be called before the context is destroyed in a
2404 * controlled way by the frontend. */
2405 retro_hw_context_reset_t context_destroy;
2406
2407 /* OpenGL resources can be deinitialized cleanly at this step.
2408 * context_destroy can be set to NULL, in which resources will
2409 * just be destroyed without any notification.
2410 *
2411 * Even when context_destroy is non-NULL, it is possible that
2412 * context_reset is called without any destroy notification.
2413 * This happens if context is lost by external factors (such as
2414 * notified by GL_ARB_robustness).
2415 *
2416 * In this case, the context is assumed to be already dead,
2417 * and the libretro implementation must not try to free any OpenGL
2418 * resources in the subsequent context_reset.
2419 */
2420
2421 /* Creates a debug context. */
2422 bool debug_context;
2423};
2424
2425/* Callback type passed in RETRO_ENVIRONMENT_SET_KEYBOARD_CALLBACK.
2426 * Called by the frontend in response to keyboard events.
2427 * down is set if the key is being pressed, or false if it is being released.
2428 * keycode is the RETROK value of the char.
2429 * character is the text character of the pressed key. (UTF-32).
2430 * key_modifiers is a set of RETROKMOD values or'ed together.
2431 *
2432 * The pressed/keycode state can be indepedent of the character.
2433 * It is also possible that multiple characters are generated from a
2434 * single keypress.
2435 * Keycode events should be treated separately from character events.
2436 * However, when possible, the frontend should try to synchronize these.
2437 * If only a character is posted, keycode should be RETROK_UNKNOWN.
2438 *
2439 * Similarily if only a keycode event is generated with no corresponding
2440 * character, character should be 0.
2441 */
2442typedef void (RETRO_CALLCONV *retro_keyboard_event_t)(bool down, unsigned keycode,
2443 uint32_t character, uint16_t key_modifiers);
2444
2445struct retro_keyboard_callback
2446{
2447 retro_keyboard_event_t callback;
2448};
2449
2450/* Callbacks for RETRO_ENVIRONMENT_SET_DISK_CONTROL_INTERFACE &
2451 * RETRO_ENVIRONMENT_SET_DISK_CONTROL_EXT_INTERFACE.
2452 * Should be set for implementations which can swap out multiple disk
2453 * images in runtime.
2454 *
2455 * If the implementation can do this automatically, it should strive to do so.
2456 * However, there are cases where the user must manually do so.
2457 *
2458 * Overview: To swap a disk image, eject the disk image with
2459 * set_eject_state(true).
2460 * Set the disk index with set_image_index(index). Insert the disk again
2461 * with set_eject_state(false).
2462 */
2463
2464/* If ejected is true, "ejects" the virtual disk tray.
2465 * When ejected, the disk image index can be set.
2466 */
2467typedef bool (RETRO_CALLCONV *retro_set_eject_state_t)(bool ejected);
2468
2469/* Gets current eject state. The initial state is 'not ejected'. */
2470typedef bool (RETRO_CALLCONV *retro_get_eject_state_t)(void);
2471
2472/* Gets current disk index. First disk is index 0.
2473 * If return value is >= get_num_images(), no disk is currently inserted.
2474 */
2475typedef unsigned (RETRO_CALLCONV *retro_get_image_index_t)(void);
2476
2477/* Sets image index. Can only be called when disk is ejected.
2478 * The implementation supports setting "no disk" by using an
2479 * index >= get_num_images().
2480 */
2481typedef bool (RETRO_CALLCONV *retro_set_image_index_t)(unsigned index);
2482
2483/* Gets total number of images which are available to use. */
2484typedef unsigned (RETRO_CALLCONV *retro_get_num_images_t)(void);
2485
2486struct retro_game_info;
2487
2488/* Replaces the disk image associated with index.
2489 * Arguments to pass in info have same requirements as retro_load_game().
2490 * Virtual disk tray must be ejected when calling this.
2491 *
2492 * Replacing a disk image with info = NULL will remove the disk image
2493 * from the internal list.
2494 * As a result, calls to get_image_index() can change.
2495 *
2496 * E.g. replace_image_index(1, NULL), and previous get_image_index()
2497 * returned 4 before.
2498 * Index 1 will be removed, and the new index is 3.
2499 */
2500typedef bool (RETRO_CALLCONV *retro_replace_image_index_t)(unsigned index,
2501 const struct retro_game_info *info);
2502
2503/* Adds a new valid index (get_num_images()) to the internal disk list.
2504 * This will increment subsequent return values from get_num_images() by 1.
2505 * This image index cannot be used until a disk image has been set
2506 * with replace_image_index. */
2507typedef bool (RETRO_CALLCONV *retro_add_image_index_t)(void);
2508
2509/* Sets initial image to insert in drive when calling
2510 * core_load_game().
2511 * Since we cannot pass the initial index when loading
2512 * content (this would require a major API change), this
2513 * is set by the frontend *before* calling the core's
2514 * retro_load_game()/retro_load_game_special() implementation.
2515 * A core should therefore cache the index/path values and handle
2516 * them inside retro_load_game()/retro_load_game_special().
2517 * - If 'index' is invalid (index >= get_num_images()), the
2518 * core should ignore the set value and instead use 0
2519 * - 'path' is used purely for error checking - i.e. when
2520 * content is loaded, the core should verify that the
2521 * disk specified by 'index' has the specified file path.
2522 * This is to guard against auto selecting the wrong image
2523 * if (for example) the user should modify an existing M3U
2524 * playlist. We have to let the core handle this because
2525 * set_initial_image() must be called before loading content,
2526 * i.e. the frontend cannot access image paths in advance
2527 * and thus cannot perform the error check itself.
2528 * If set path and content path do not match, the core should
2529 * ignore the set 'index' value and instead use 0
2530 * Returns 'false' if index or 'path' are invalid, or core
2531 * does not support this functionality
2532 */
2533typedef bool (RETRO_CALLCONV *retro_set_initial_image_t)(unsigned index, const char *path);
2534
2535/* Fetches the path of the specified disk image file.
2536 * Returns 'false' if index is invalid (index >= get_num_images())
2537 * or path is otherwise unavailable.
2538 */
2539typedef bool (RETRO_CALLCONV *retro_get_image_path_t)(unsigned index, char *path, size_t len);
2540
2541/* Fetches a core-provided 'label' for the specified disk
2542 * image file. In the simplest case this may be a file name
2543 * (without extension), but for cores with more complex
2544 * content requirements information may be provided to
2545 * facilitate user disk swapping - for example, a core
2546 * running floppy-disk-based content may uniquely label
2547 * save disks, data disks, level disks, etc. with names
2548 * corresponding to in-game disk change prompts (so the
2549 * frontend can provide better user guidance than a 'dumb'
2550 * disk index value).
2551 * Returns 'false' if index is invalid (index >= get_num_images())
2552 * or label is otherwise unavailable.
2553 */
2554typedef bool (RETRO_CALLCONV *retro_get_image_label_t)(unsigned index, char *label, size_t len);
2555
2556struct retro_disk_control_callback
2557{
2558 retro_set_eject_state_t set_eject_state;
2559 retro_get_eject_state_t get_eject_state;
2560
2561 retro_get_image_index_t get_image_index;
2562 retro_set_image_index_t set_image_index;
2563 retro_get_num_images_t get_num_images;
2564
2565 retro_replace_image_index_t replace_image_index;
2566 retro_add_image_index_t add_image_index;
2567};
2568
2569struct retro_disk_control_ext_callback
2570{
2571 retro_set_eject_state_t set_eject_state;
2572 retro_get_eject_state_t get_eject_state;
2573
2574 retro_get_image_index_t get_image_index;
2575 retro_set_image_index_t set_image_index;
2576 retro_get_num_images_t get_num_images;
2577
2578 retro_replace_image_index_t replace_image_index;
2579 retro_add_image_index_t add_image_index;
2580
2581 /* NOTE: Frontend will only attempt to record/restore
2582 * last used disk index if both set_initial_image()
2583 * and get_image_path() are implemented */
2584 retro_set_initial_image_t set_initial_image; /* Optional - may be NULL */
2585
2586 retro_get_image_path_t get_image_path; /* Optional - may be NULL */
2587 retro_get_image_label_t get_image_label; /* Optional - may be NULL */
2588};
2589
2590enum retro_pixel_format
2591{
2592 /* 0RGB1555, native endian.
2593 * 0 bit must be set to 0.
2594 * This pixel format is default for compatibility concerns only.
2595 * If a 15/16-bit pixel format is desired, consider using RGB565. */
2596 RETRO_PIXEL_FORMAT_0RGB1555 = 0,
2597
2598 /* XRGB8888, native endian.
2599 * X bits are ignored. */
2600 RETRO_PIXEL_FORMAT_XRGB8888 = 1,
2601
2602 /* RGB565, native endian.
2603 * This pixel format is the recommended format to use if a 15/16-bit
2604 * format is desired as it is the pixel format that is typically
2605 * available on a wide range of low-power devices.
2606 *
2607 * It is also natively supported in APIs like OpenGL ES. */
2608 RETRO_PIXEL_FORMAT_RGB565 = 2,
2609
2610 /* Ensure sizeof() == sizeof(int). */
2611 RETRO_PIXEL_FORMAT_UNKNOWN = INT_MAX
2612};
2613
2614struct retro_message
2615{
2616 const char *msg; /* Message to be displayed. */
2617 unsigned frames; /* Duration in frames of message. */
2618};
2619
2620enum retro_message_target
2621{
2622 RETRO_MESSAGE_TARGET_ALL = 0,
2623 RETRO_MESSAGE_TARGET_OSD,
2624 RETRO_MESSAGE_TARGET_LOG
2625};
2626
2627enum retro_message_type
2628{
2629 RETRO_MESSAGE_TYPE_NOTIFICATION = 0,
2630 RETRO_MESSAGE_TYPE_NOTIFICATION_ALT,
2631 RETRO_MESSAGE_TYPE_STATUS,
2632 RETRO_MESSAGE_TYPE_PROGRESS
2633};
2634
2635struct retro_message_ext
2636{
2637 /* Message string to be displayed/logged */
2638 const char *msg;
2639 /* Duration (in ms) of message when targeting the OSD */
2640 unsigned duration;
2641 /* Message priority when targeting the OSD
2642 * > When multiple concurrent messages are sent to
2643 * the frontend and the frontend does not have the
2644 * capacity to display them all, messages with the
2645 * *highest* priority value should be shown
2646 * > There is no upper limit to a message priority
2647 * value (within the bounds of the unsigned data type)
2648 * > In the reference frontend (RetroArch), the same
2649 * priority values are used for frontend-generated
2650 * notifications, which are typically assigned values
2651 * between 0 and 3 depending upon importance */
2652 unsigned priority;
2653 /* Message logging level (info, warn, error, etc.) */
2654 enum retro_log_level level;
2655 /* Message destination: OSD, logging interface or both */
2656 enum retro_message_target target;
2657 /* Message 'type' when targeting the OSD
2658 * > RETRO_MESSAGE_TYPE_NOTIFICATION: Specifies that a
2659 * message should be handled in identical fashion to
2660 * a standard frontend-generated notification
2661 * > RETRO_MESSAGE_TYPE_NOTIFICATION_ALT: Specifies that
2662 * message is a notification that requires user attention
2663 * or action, but that it should be displayed in a manner
2664 * that differs from standard frontend-generated notifications.
2665 * This would typically correspond to messages that should be
2666 * displayed immediately (independently from any internal
2667 * frontend message queue), and/or which should be visually
2668 * distinguishable from frontend-generated notifications.
2669 * For example, a core may wish to inform the user of
2670 * information related to a disk-change event. It is
2671 * expected that the frontend itself may provide a
2672 * notification in this case; if the core sends a
2673 * message of type RETRO_MESSAGE_TYPE_NOTIFICATION, an
2674 * uncomfortable 'double-notification' may occur. A message
2675 * of RETRO_MESSAGE_TYPE_NOTIFICATION_ALT should therefore
2676 * be presented such that visual conflict with regular
2677 * notifications does not occur
2678 * > RETRO_MESSAGE_TYPE_STATUS: Indicates that message
2679 * is not a standard notification. This typically
2680 * corresponds to 'status' indicators, such as a core's
2681 * internal FPS, which are intended to be displayed
2682 * either permanently while a core is running, or in
2683 * a manner that does not suggest user attention or action
2684 * is required. 'Status' type messages should therefore be
2685 * displayed in a different on-screen location and in a manner
2686 * easily distinguishable from both standard frontend-generated
2687 * notifications and messages of type RETRO_MESSAGE_TYPE_NOTIFICATION_ALT
2688 * > RETRO_MESSAGE_TYPE_PROGRESS: Indicates that message reports
2689 * the progress of an internal core task. For example, in cases
2690 * where a core itself handles the loading of content from a file,
2691 * this may correspond to the percentage of the file that has been
2692 * read. Alternatively, an audio/video playback core may use a
2693 * message of type RETRO_MESSAGE_TYPE_PROGRESS to display the current
2694 * playback position as a percentage of the runtime. 'Progress' type
2695 * messages should therefore be displayed as a literal progress bar,
2696 * where:
2697 * - 'retro_message_ext.msg' is the progress bar title/label
2698 * - 'retro_message_ext.progress' determines the length of
2699 * the progress bar
2700 * NOTE: Message type is a *hint*, and may be ignored
2701 * by the frontend. If a frontend lacks support for
2702 * displaying messages via alternate means than standard
2703 * frontend-generated notifications, it will treat *all*
2704 * messages as having the type RETRO_MESSAGE_TYPE_NOTIFICATION */
2705 enum retro_message_type type;
2706 /* Task progress when targeting the OSD and message is
2707 * of type RETRO_MESSAGE_TYPE_PROGRESS
2708 * > -1: Unmetered/indeterminate
2709 * > 0-100: Current progress percentage
2710 * NOTE: Since message type is a hint, a frontend may ignore
2711 * progress values. Where relevant, a core should therefore
2712 * include progress percentage within the message string,
2713 * such that the message intent remains clear when displayed
2714 * as a standard frontend-generated notification */
2715 int8_t progress;
2716};
2717
2718/* Describes how the libretro implementation maps a libretro input bind
2719 * to its internal input system through a human readable string.
2720 * This string can be used to better let a user configure input. */
2721struct retro_input_descriptor
2722{
2723 /* Associates given parameters with a description. */
2724 unsigned port;
2725 unsigned device;
2726 unsigned index;
2727 unsigned id;
2728
2729 /* Human readable description for parameters.
2730 * The pointer must remain valid until
2731 * retro_unload_game() is called. */
2732 const char *description;
2733};
2734
2735struct retro_system_info
2736{
2737 /* All pointers are owned by libretro implementation, and pointers must
2738 * remain valid until it is unloaded. */
2739
2740 const char *library_name; /* Descriptive name of library. Should not
2741 * contain any version numbers, etc. */
2742 const char *library_version; /* Descriptive version of core. */
2743
2744 const char *valid_extensions; /* A string listing probably content
2745 * extensions the core will be able to
2746 * load, separated with pipe.
2747 * I.e. "bin|rom|iso".
2748 * Typically used for a GUI to filter
2749 * out extensions. */
2750
2751 /* Libretro cores that need to have direct access to their content
2752 * files, including cores which use the path of the content files to
2753 * determine the paths of other files, should set need_fullpath to true.
2754 *
2755 * Cores should strive for setting need_fullpath to false,
2756 * as it allows the frontend to perform patching, etc.
2757 *
2758 * If need_fullpath is true and retro_load_game() is called:
2759 * - retro_game_info::path is guaranteed to have a valid path
2760 * - retro_game_info::data and retro_game_info::size are invalid
2761 *
2762 * If need_fullpath is false and retro_load_game() is called:
2763 * - retro_game_info::path may be NULL
2764 * - retro_game_info::data and retro_game_info::size are guaranteed
2765 * to be valid
2766 *
2767 * See also:
2768 * - RETRO_ENVIRONMENT_GET_SYSTEM_DIRECTORY
2769 * - RETRO_ENVIRONMENT_GET_SAVE_DIRECTORY
2770 */
2771 bool need_fullpath;
2772
2773 /* If true, the frontend is not allowed to extract any archives before
2774 * loading the real content.
2775 * Necessary for certain libretro implementations that load games
2776 * from zipped archives. */
2777 bool block_extract;
2778};
2779
2780struct retro_game_geometry
2781{
2782 unsigned base_width; /* Nominal video width of game. */
2783 unsigned base_height; /* Nominal video height of game. */
2784 unsigned max_width; /* Maximum possible width of game. */
2785 unsigned max_height; /* Maximum possible height of game. */
2786
2787 float aspect_ratio; /* Nominal aspect ratio of game. If
2788 * aspect_ratio is <= 0.0, an aspect ratio
2789 * of base_width / base_height is assumed.
2790 * A frontend could override this setting,
2791 * if desired. */
2792};
2793
2794struct retro_system_timing
2795{
2796 double fps; /* FPS of video content. */
2797 double sample_rate; /* Sampling rate of audio. */
2798};
2799
2800struct retro_system_av_info
2801{
2802 struct retro_game_geometry geometry;
2803 struct retro_system_timing timing;
2804};
2805
2806struct retro_variable
2807{
2808 /* Variable to query in RETRO_ENVIRONMENT_GET_VARIABLE.
2809 * If NULL, obtains the complete environment string if more
2810 * complex parsing is necessary.
2811 * The environment string is formatted as key-value pairs
2812 * delimited by semicolons as so:
2813 * "key1=value1;key2=value2;..."
2814 */
2815 const char *key;
2816
2817 /* Value to be obtained. If key does not exist, it is set to NULL. */
2818 const char *value;
2819};
2820
2821struct retro_core_option_display
2822{
2823 /* Variable to configure in RETRO_ENVIRONMENT_SET_CORE_OPTIONS_DISPLAY */
2824 const char *key;
2825
2826 /* Specifies whether variable should be displayed
2827 * when presenting core options to the user */
2828 bool visible;
2829};
2830
2831/* Maximum number of values permitted for a core option
2832 * > Note: We have to set a maximum value due the limitations
2833 * of the C language - i.e. it is not possible to create an
2834 * array of structs each containing a variable sized array,
2835 * so the retro_core_option_definition values array must
2836 * have a fixed size. The size limit of 128 is a balancing
2837 * act - it needs to be large enough to support all 'sane'
2838 * core options, but setting it too large may impact low memory
2839 * platforms. In practise, if a core option has more than
2840 * 128 values then the implementation is likely flawed.
2841 * To quote the above API reference:
2842 * "The number of possible options should be very limited
2843 * i.e. it should be feasible to cycle through options
2844 * without a keyboard."
2845 */
2846#define RETRO_NUM_CORE_OPTION_VALUES_MAX 128
2847
2848struct retro_core_option_value
2849{
2850 /* Expected option value */
2851 const char *value;
2852
2853 /* Human-readable value label. If NULL, value itself
2854 * will be displayed by the frontend */
2855 const char *label;
2856};
2857
2858struct retro_core_option_definition
2859{
2860 /* Variable to query in RETRO_ENVIRONMENT_GET_VARIABLE. */
2861 const char *key;
2862
2863 /* Human-readable core option description (used as menu label) */
2864 const char *desc;
2865
2866 /* Human-readable core option information (used as menu sublabel) */
2867 const char *info;
2868
2869 /* Array of retro_core_option_value structs, terminated by NULL */
2870 struct retro_core_option_value values[RETRO_NUM_CORE_OPTION_VALUES_MAX];
2871
2872 /* Default core option value. Must match one of the values
2873 * in the retro_core_option_value array, otherwise will be
2874 * ignored */
2875 const char *default_value;
2876};
2877
2878struct retro_core_options_intl
2879{
2880 /* Pointer to an array of retro_core_option_definition structs
2881 * - US English implementation
2882 * - Must point to a valid array */
2883 struct retro_core_option_definition *us;
2884
2885 /* Pointer to an array of retro_core_option_definition structs
2886 * - Implementation for current frontend language
2887 * - May be NULL */
2888 struct retro_core_option_definition *local;
2889};
2890
2891struct retro_game_info
2892{
2893 const char *path; /* Path to game, UTF-8 encoded.
2894 * Sometimes used as a reference for building other paths.
2895 * May be NULL if game was loaded from stdin or similar,
2896 * but in this case some cores will be unable to load `data`.
2897 * So, it is preferable to fabricate something here instead
2898 * of passing NULL, which will help more cores to succeed.
2899 * retro_system_info::need_fullpath requires
2900 * that this path is valid. */
2901 const void *data; /* Memory buffer of loaded game. Will be NULL
2902 * if need_fullpath was set. */
2903 size_t size; /* Size of memory buffer. */
2904 const char *meta; /* String of implementation specific meta-data. */
2905};
2906
2907#define RETRO_MEMORY_ACCESS_WRITE (1 << 0)
2908 /* The core will write to the buffer provided by retro_framebuffer::data. */
2909#define RETRO_MEMORY_ACCESS_READ (1 << 1)
2910 /* The core will read from retro_framebuffer::data. */
2911#define RETRO_MEMORY_TYPE_CACHED (1 << 0)
2912 /* The memory in data is cached.
2913 * If not cached, random writes and/or reading from the buffer is expected to be very slow. */
2914struct retro_framebuffer
2915{
2916 void *data; /* The framebuffer which the core can render into.
2917 Set by frontend in GET_CURRENT_SOFTWARE_FRAMEBUFFER.
2918 The initial contents of data are unspecified. */
2919 unsigned width; /* The framebuffer width used by the core. Set by core. */
2920 unsigned height; /* The framebuffer height used by the core. Set by core. */
2921 size_t pitch; /* The number of bytes between the beginning of a scanline,
2922 and beginning of the next scanline.
2923 Set by frontend in GET_CURRENT_SOFTWARE_FRAMEBUFFER. */
2924 enum retro_pixel_format format; /* The pixel format the core must use to render into data.
2925 This format could differ from the format used in
2926 SET_PIXEL_FORMAT.
2927 Set by frontend in GET_CURRENT_SOFTWARE_FRAMEBUFFER. */
2928
2929 unsigned access_flags; /* How the core will access the memory in the framebuffer.
2930 RETRO_MEMORY_ACCESS_* flags.
2931 Set by core. */
2932 unsigned memory_flags; /* Flags telling core how the memory has been mapped.
2933 RETRO_MEMORY_TYPE_* flags.
2934 Set by frontend in GET_CURRENT_SOFTWARE_FRAMEBUFFER. */
2935};
2936
2937/* Callbacks */
2938
2939/* Environment callback. Gives implementations a way of performing
2940 * uncommon tasks. Extensible. */
2941typedef bool (RETRO_CALLCONV *retro_environment_t)(unsigned cmd, void *data);
2942
2943/* Render a frame. Pixel format is 15-bit 0RGB1555 native endian
2944 * unless changed (see RETRO_ENVIRONMENT_SET_PIXEL_FORMAT).
2945 *
2946 * Width and height specify dimensions of buffer.
2947 * Pitch specifices length in bytes between two lines in buffer.
2948 *
2949 * For performance reasons, it is highly recommended to have a frame
2950 * that is packed in memory, i.e. pitch == width * byte_per_pixel.
2951 * Certain graphic APIs, such as OpenGL ES, do not like textures
2952 * that are not packed in memory.
2953 */
2954typedef void (RETRO_CALLCONV *retro_video_refresh_t)(const void *data, unsigned width,
2955 unsigned height, size_t pitch);
2956
2957/* Renders a single audio frame. Should only be used if implementation
2958 * generates a single sample at a time.
2959 * Format is signed 16-bit native endian.
2960 */
2961typedef void (RETRO_CALLCONV *retro_audio_sample_t)(int16_t left, int16_t right);
2962
2963/* Renders multiple audio frames in one go.
2964 *
2965 * One frame is defined as a sample of left and right channels, interleaved.
2966 * I.e. int16_t buf[4] = { l, r, l, r }; would be 2 frames.
2967 * Only one of the audio callbacks must ever be used.
2968 */
2969typedef size_t (RETRO_CALLCONV *retro_audio_sample_batch_t)(const int16_t *data,
2970 size_t frames);
2971
2972/* Polls input. */
2973typedef void (RETRO_CALLCONV *retro_input_poll_t)(void);
2974
2975/* Queries for input for player 'port'. device will be masked with
2976 * RETRO_DEVICE_MASK.
2977 *
2978 * Specialization of devices such as RETRO_DEVICE_JOYPAD_MULTITAP that
2979 * have been set with retro_set_controller_port_device()
2980 * will still use the higher level RETRO_DEVICE_JOYPAD to request input.
2981 */
2982typedef int16_t (RETRO_CALLCONV *retro_input_state_t)(unsigned port, unsigned device,
2983 unsigned index, unsigned id);
2984
2985/* Sets callbacks. retro_set_environment() is guaranteed to be called
2986 * before retro_init().
2987 *
2988 * The rest of the set_* functions are guaranteed to have been called
2989 * before the first call to retro_run() is made. */
2990RETRO_API void retro_set_environment(retro_environment_t);
2991RETRO_API void retro_set_video_refresh(retro_video_refresh_t);
2992RETRO_API void retro_set_audio_sample(retro_audio_sample_t);
2993RETRO_API void retro_set_audio_sample_batch(retro_audio_sample_batch_t);
2994RETRO_API void retro_set_input_poll(retro_input_poll_t);
2995RETRO_API void retro_set_input_state(retro_input_state_t);
2996
2997/* Library global initialization/deinitialization. */
2998RETRO_API void retro_init(void);
2999RETRO_API void retro_deinit(void);
3000
3001/* Must return RETRO_API_VERSION. Used to validate ABI compatibility
3002 * when the API is revised. */
3003RETRO_API unsigned retro_api_version(void);
3004
3005/* Gets statically known system info. Pointers provided in *info
3006 * must be statically allocated.
3007 * Can be called at any time, even before retro_init(). */
3008RETRO_API void retro_get_system_info(struct retro_system_info *info);
3009
3010/* Gets information about system audio/video timings and geometry.
3011 * Can be called only after retro_load_game() has successfully completed.
3012 * NOTE: The implementation of this function might not initialize every
3013 * variable if needed.
3014 * E.g. geom.aspect_ratio might not be initialized if core doesn't
3015 * desire a particular aspect ratio. */
3016RETRO_API void retro_get_system_av_info(struct retro_system_av_info *info);
3017
3018/* Sets device to be used for player 'port'.
3019 * By default, RETRO_DEVICE_JOYPAD is assumed to be plugged into all
3020 * available ports.
3021 * Setting a particular device type is not a guarantee that libretro cores
3022 * will only poll input based on that particular device type. It is only a
3023 * hint to the libretro core when a core cannot automatically detect the
3024 * appropriate input device type on its own. It is also relevant when a
3025 * core can change its behavior depending on device type.
3026 *
3027 * As part of the core's implementation of retro_set_controller_port_device,
3028 * the core should call RETRO_ENVIRONMENT_SET_INPUT_DESCRIPTORS to notify the
3029 * frontend if the descriptions for any controls have changed as a
3030 * result of changing the device type.
3031 */
3032RETRO_API void retro_set_controller_port_device(unsigned port, unsigned device);
3033
3034/* Resets the current game. */
3035RETRO_API void retro_reset(void);
3036
3037/* Runs the game for one video frame.
3038 * During retro_run(), input_poll callback must be called at least once.
3039 *
3040 * If a frame is not rendered for reasons where a game "dropped" a frame,
3041 * this still counts as a frame, and retro_run() should explicitly dupe
3042 * a frame if GET_CAN_DUPE returns true.
3043 * In this case, the video callback can take a NULL argument for data.
3044 */
3045RETRO_API void retro_run(void);
3046
3047/* Returns the amount of data the implementation requires to serialize
3048 * internal state (save states).
3049 * Between calls to retro_load_game() and retro_unload_game(), the
3050 * returned size is never allowed to be larger than a previous returned
3051 * value, to ensure that the frontend can allocate a save state buffer once.
3052 */
3053RETRO_API size_t retro_serialize_size(void);
3054
3055/* Serializes internal state. If failed, or size is lower than
3056 * retro_serialize_size(), it should return false, true otherwise. */
3057RETRO_API bool retro_serialize(void *data, size_t size);
3058RETRO_API bool retro_unserialize(const void *data, size_t size);
3059
3060RETRO_API void retro_cheat_reset(void);
3061RETRO_API void retro_cheat_set(unsigned index, bool enabled, const char *code);
3062
3063/* Loads a game.
3064 * Return true to indicate successful loading and false to indicate load failure.
3065 */
3066RETRO_API bool retro_load_game(const struct retro_game_info *game);
3067
3068/* Loads a "special" kind of game. Should not be used,
3069 * except in extreme cases. */
3070RETRO_API bool retro_load_game_special(
3071 unsigned game_type,
3072 const struct retro_game_info *info, size_t num_info
3073);
3074
3075/* Unloads the currently loaded game. Called before retro_deinit(void). */
3076RETRO_API void retro_unload_game(void);
3077
3078/* Gets region of game. */
3079RETRO_API unsigned retro_get_region(void);
3080
3081/* Gets region of memory. */
3082RETRO_API void *retro_get_memory_data(unsigned id);
3083RETRO_API size_t retro_get_memory_size(unsigned id);
3084
3085#ifdef __cplusplus
3086}
3087#endif
3088
3089#endif