src/gb/video.c (view raw)
1/* Copyright (c) 2013-2016 Jeffrey Pfau
2 *
3 * This Source Code Form is subject to the terms of the Mozilla Public
4 * License, v. 2.0. If a copy of the MPL was not distributed with this
5 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
6#include "video.h"
7
8#include "core/sync.h"
9#include "core/thread.h"
10#include "gb/gb.h"
11#include "gb/io.h"
12#include "gb/serialize.h"
13
14#include "util/memory.h"
15
16static void GBVideoDummyRendererInit(struct GBVideoRenderer* renderer, enum GBModel model);
17static void GBVideoDummyRendererDeinit(struct GBVideoRenderer* renderer);
18static uint8_t GBVideoDummyRendererWriteVideoRegister(struct GBVideoRenderer* renderer, uint16_t address, uint8_t value);
19static void GBVideoDummyRendererWritePalette(struct GBVideoRenderer* renderer, int index, uint16_t value);
20static void GBVideoDummyRendererDrawRange(struct GBVideoRenderer* renderer, int startX, int endX, int y, struct GBObj* obj, size_t oamMax);
21static void GBVideoDummyRendererFinishScanline(struct GBVideoRenderer* renderer, int y);
22static void GBVideoDummyRendererFinishFrame(struct GBVideoRenderer* renderer);
23static void GBVideoDummyRendererGetPixels(struct GBVideoRenderer* renderer, unsigned* stride, const void** pixels);
24
25static void _cleanOAM(struct GBVideo* video, int y);
26
27static struct GBVideoRenderer dummyRenderer = {
28 .init = GBVideoDummyRendererInit,
29 .deinit = GBVideoDummyRendererDeinit,
30 .writeVideoRegister = GBVideoDummyRendererWriteVideoRegister,
31 .writePalette = GBVideoDummyRendererWritePalette,
32 .drawRange = GBVideoDummyRendererDrawRange,
33 .finishScanline = GBVideoDummyRendererFinishScanline,
34 .finishFrame = GBVideoDummyRendererFinishFrame,
35 .getPixels = GBVideoDummyRendererGetPixels
36};
37
38void GBVideoInit(struct GBVideo* video) {
39 video->renderer = &dummyRenderer;
40 video->vram = 0;
41 video->frameskip = 0;
42}
43
44void GBVideoReset(struct GBVideo* video) {
45 video->ly = 0;
46 video->x = 0;
47 video->mode = 1;
48 video->stat = 1;
49
50 video->nextEvent = INT_MAX;
51 video->eventDiff = 0;
52
53 video->nextMode = INT_MAX;
54 video->dotCounter = INT_MIN;
55 video->nextFrame = INT_MAX;
56
57 video->frameCounter = 0;
58 video->frameskipCounter = 0;
59
60 if (video->vram) {
61 mappedMemoryFree(video->vram, GB_SIZE_VRAM);
62 }
63 video->vram = anonymousMemoryMap(GB_SIZE_VRAM);
64 GBVideoSwitchBank(video, 0);
65 video->renderer->vram = video->vram;
66 memset(&video->oam, 0, sizeof(video->oam));
67 video->renderer->oam = &video->oam;
68 memset(&video->palette, 0, sizeof(video->palette));
69
70 video->renderer->deinit(video->renderer);
71 video->renderer->init(video->renderer, video->p->model);
72}
73
74void GBVideoDeinit(struct GBVideo* video) {
75 GBVideoAssociateRenderer(video, &dummyRenderer);
76 mappedMemoryFree(video->vram, GB_SIZE_VRAM);
77}
78
79void GBVideoAssociateRenderer(struct GBVideo* video, struct GBVideoRenderer* renderer) {
80 video->renderer->deinit(video->renderer);
81 video->renderer = renderer;
82 renderer->vram = video->vram;
83 video->renderer->init(video->renderer, video->p->model);
84}
85
86int32_t GBVideoProcessEvents(struct GBVideo* video, int32_t cycles) {
87 video->eventDiff += cycles;
88 if (video->nextEvent != INT_MAX) {
89 video->nextEvent -= cycles;
90 }
91 if (video->nextEvent <= 0) {
92 if (video->nextEvent != INT_MAX) {
93 video->nextMode -= video->eventDiff;
94 video->nextFrame -= video->eventDiff;
95 }
96 video->nextEvent = INT_MAX;
97 GBVideoProcessDots(video);
98 if (video->nextMode <= 0) {
99 int lyc = video->p->memory.io[REG_LYC];
100 switch (video->mode) {
101 case 0:
102 if (video->frameskipCounter <= 0) {
103 video->renderer->finishScanline(video->renderer, video->ly);
104 }
105 ++video->ly;
106 video->p->memory.io[REG_LY] = video->ly;
107 video->stat = GBRegisterSTATSetLYC(video->stat, lyc == video->ly);
108 if (video->ly < GB_VIDEO_VERTICAL_PIXELS) {
109 video->nextMode = GB_VIDEO_MODE_2_LENGTH;
110 video->mode = 2;
111 if (!GBRegisterSTATIsHblankIRQ(video->stat) && GBRegisterSTATIsOAMIRQ(video->stat)) {
112 video->p->memory.io[REG_IF] |= (1 << GB_IRQ_LCDSTAT);
113 }
114 } else {
115 video->nextMode = GB_VIDEO_HORIZONTAL_LENGTH;
116 video->mode = 1;
117 --video->frameskipCounter;
118 if (video->frameskipCounter < 0) {
119 mCoreSyncPostFrame(video->p->sync);
120 video->frameskipCounter = video->frameskip;
121 }
122 ++video->frameCounter;
123
124 if (video->nextFrame != 0) {
125 video->nextFrame = 0;
126 }
127
128 if (video->p->stream && video->p->stream->postVideoFrame) {
129 const color_t* pixels;
130 unsigned stride;
131 video->renderer->getPixels(video->renderer, &stride, (const void**) &pixels);
132 video->p->stream->postVideoFrame(video->p->stream, pixels, stride);
133 }
134
135 if (GBRegisterSTATIsVblankIRQ(video->stat) || GBRegisterSTATIsOAMIRQ(video->stat)) {
136 video->p->memory.io[REG_IF] |= (1 << GB_IRQ_LCDSTAT);
137 }
138 video->p->memory.io[REG_IF] |= (1 << GB_IRQ_VBLANK);
139 }
140 if (GBRegisterSTATIsLYCIRQ(video->stat) && lyc == video->ly) {
141 video->p->memory.io[REG_IF] |= (1 << GB_IRQ_LCDSTAT);
142 }
143 GBUpdateIRQs(video->p);
144 break;
145 case 1:
146 // TODO: One M-cycle delay
147 ++video->ly;
148 if (video->ly == GB_VIDEO_VERTICAL_TOTAL_PIXELS + 1) {
149 video->ly = 0;
150 video->p->memory.io[REG_LY] = video->ly;
151 video->nextMode = GB_VIDEO_MODE_2_LENGTH;
152 video->mode = 2;
153 if (GBRegisterSTATIsOAMIRQ(video->stat)) {
154 video->p->memory.io[REG_IF] |= (1 << GB_IRQ_LCDSTAT);
155 GBUpdateIRQs(video->p);
156 }
157 video->renderer->finishFrame(video->renderer);
158 break;
159 } else if (video->ly == GB_VIDEO_VERTICAL_TOTAL_PIXELS) {
160 video->p->memory.io[REG_LY] = 0;
161 video->nextMode = GB_VIDEO_HORIZONTAL_LENGTH - 8;
162 } else if (video->ly == GB_VIDEO_VERTICAL_TOTAL_PIXELS - 1) {
163 video->p->memory.io[REG_LY] = video->ly;
164 video->nextMode = 8;
165 } else {
166 video->p->memory.io[REG_LY] = video->ly;
167 video->nextMode = GB_VIDEO_HORIZONTAL_LENGTH;
168 }
169
170 video->stat = GBRegisterSTATSetLYC(video->stat, lyc == video->p->memory.io[REG_LY]);
171 if (GBRegisterSTATIsLYCIRQ(video->stat) && lyc == video->p->memory.io[REG_LY]) {
172 video->p->memory.io[REG_IF] |= (1 << GB_IRQ_LCDSTAT);
173 GBUpdateIRQs(video->p);
174 }
175 if (video->p->memory.mbcType == GB_MBC7 && video->p->memory.rotation && video->p->memory.rotation->sample) {
176 video->p->memory.rotation->sample(video->p->memory.rotation);
177 }
178 break;
179 case 2:
180 _cleanOAM(video, video->ly);
181 video->dotCounter = 0;
182 video->nextEvent = GB_VIDEO_HORIZONTAL_LENGTH;
183 video->x = 0;
184 video->nextMode = GB_VIDEO_MODE_3_LENGTH_BASE + video->objMax * 12;
185 video->mode = 3;
186 break;
187 case 3:
188 video->nextMode = GB_VIDEO_MODE_0_LENGTH_BASE - video->objMax * 12;
189 video->mode = 0;
190 if (GBRegisterSTATIsHblankIRQ(video->stat)) {
191 video->p->memory.io[REG_IF] |= (1 << GB_IRQ_LCDSTAT);
192 GBUpdateIRQs(video->p);
193 }
194 if (video->ly < GB_VIDEO_VERTICAL_PIXELS && video->p->memory.isHdma && video->p->memory.io[REG_HDMA5] != 0xFF) {
195 video->p->memory.hdmaRemaining = 0x10;
196 video->p->memory.hdmaNext = video->p->cpu->cycles;
197 }
198 break;
199 }
200 video->stat = GBRegisterSTATSetMode(video->stat, video->mode);
201 video->p->memory.io[REG_STAT] = video->stat;
202 }
203 if (video->nextFrame <= 0) {
204 if (video->p->cpu->executionState == LR35902_CORE_FETCH) {
205 GBFrameEnded(video->p);
206 struct mCoreThread* thread = mCoreThreadGet();
207 if (thread && thread->frameCallback) {
208 thread->frameCallback(thread);
209 }
210 video->nextFrame = GB_VIDEO_TOTAL_LENGTH;
211 } else {
212 video->nextFrame = 4 - ((video->p->cpu->executionState + 1) & 3);
213 if (video->nextFrame < video->nextEvent) {
214 video->nextEvent = video->nextFrame;
215 }
216 }
217 }
218 if (video->nextMode < video->nextEvent) {
219 video->nextEvent = video->nextMode;
220 }
221 video->eventDiff = 0;
222 }
223 return video->nextEvent;
224}
225
226static void _cleanOAM(struct GBVideo* video, int y) {
227 // TODO: GBC differences
228 // TODO: Optimize
229 video->objMax = 0;
230 int spriteHeight = 8;
231 if (GBRegisterLCDCIsObjSize(video->p->memory.io[REG_LCDC])) {
232 spriteHeight = 16;
233 }
234 int o = 0;
235 int i;
236 for (i = 0; i < 40; ++i) {
237 uint8_t oy = video->oam.obj[i].y;
238 if (y < oy - 16 || y >= oy - 16 + spriteHeight) {
239 continue;
240 }
241 // TODO: Sort
242 video->objThisLine[o] = video->oam.obj[i];
243 ++o;
244 if (o == 10) {
245 break;
246 }
247 }
248 video->objMax = o;
249}
250
251void GBVideoProcessDots(struct GBVideo* video) {
252 if (video->mode != 3 || video->dotCounter < 0) {
253 return;
254 }
255 int oldX = video->x;
256 video->x = video->dotCounter + video->eventDiff + (video->p->cpu->cycles >> video->p->doubleSpeed);
257 if (video->x > GB_VIDEO_HORIZONTAL_PIXELS) {
258 video->x = GB_VIDEO_HORIZONTAL_PIXELS;
259 }
260 if (video->x == GB_VIDEO_HORIZONTAL_PIXELS) {
261 video->dotCounter = INT_MIN;
262 }
263 if (video->frameskipCounter <= 0) {
264 video->renderer->drawRange(video->renderer, oldX, video->x, video->ly, video->objThisLine, video->objMax);
265 }
266}
267
268void GBVideoWriteLCDC(struct GBVideo* video, GBRegisterLCDC value) {
269 if (!GBRegisterLCDCIsEnable(video->p->memory.io[REG_LCDC]) && GBRegisterLCDCIsEnable(value)) {
270 video->mode = 2;
271 video->nextMode = GB_VIDEO_MODE_2_LENGTH - 5; // TODO: Why is this fudge factor needed? Might be related to T-cycles for load/store differing
272 video->nextEvent = video->nextMode;
273 video->eventDiff = -video->p->cpu->cycles >> video->p->doubleSpeed;
274 video->ly = 0;
275 video->p->memory.io[REG_LY] = 0;
276 // TODO: Does this read as 0 for 4 T-cycles?
277 video->stat = GBRegisterSTATSetMode(video->stat, 2);
278 video->stat = GBRegisterSTATSetLYC(video->stat, video->ly == video->p->memory.io[REG_LYC]);
279 if (GBRegisterSTATIsLYCIRQ(video->stat) && video->ly == video->p->memory.io[REG_LYC]) {
280 video->p->memory.io[REG_IF] |= (1 << GB_IRQ_LCDSTAT);
281 GBUpdateIRQs(video->p);
282 }
283 video->p->memory.io[REG_STAT] = video->stat;
284
285 if (video->p->cpu->cycles + (video->nextEvent << video->p->doubleSpeed) < video->p->cpu->nextEvent) {
286 video->p->cpu->nextEvent = video->p->cpu->cycles + (video->nextEvent << video->p->doubleSpeed);
287 }
288 return;
289 }
290 if (GBRegisterLCDCIsEnable(video->p->memory.io[REG_LCDC]) && !GBRegisterLCDCIsEnable(value)) {
291 video->mode = 0;
292 video->nextMode = INT_MAX;
293 video->nextEvent = INT_MAX;
294 video->stat = GBRegisterSTATSetMode(video->stat, video->mode);
295 video->p->memory.io[REG_STAT] = video->stat;
296 video->ly = 0;
297 video->p->memory.io[REG_LY] = 0;
298 }
299}
300
301void GBVideoWriteSTAT(struct GBVideo* video, GBRegisterSTAT value) {
302 video->stat = (video->stat & 0x7) | (value & 0x78);
303 if (video->p->model == GB_MODEL_DMG && video->mode == 1) {
304 video->p->memory.io[REG_IF] |= (1 << GB_IRQ_LCDSTAT);
305 GBUpdateIRQs(video->p);
306 }
307}
308
309void GBVideoWritePalette(struct GBVideo* video, uint16_t address, uint8_t value) {
310 static const uint16_t dmgPalette[4] = { 0x7FFF, 0x56B5, 0x294A, 0x0000};
311 if (video->p->model < GB_MODEL_CGB) {
312 switch (address) {
313 case REG_BGP:
314 video->palette[0] = dmgPalette[value & 3];
315 video->palette[1] = dmgPalette[(value >> 2) & 3];
316 video->palette[2] = dmgPalette[(value >> 4) & 3];
317 video->palette[3] = dmgPalette[(value >> 6) & 3];
318 video->renderer->writePalette(video->renderer, 0, video->palette[0]);
319 video->renderer->writePalette(video->renderer, 1, video->palette[1]);
320 video->renderer->writePalette(video->renderer, 2, video->palette[2]);
321 video->renderer->writePalette(video->renderer, 3, video->palette[3]);
322 break;
323 case REG_OBP0:
324 video->palette[8 * 4 + 0] = dmgPalette[value & 3];
325 video->palette[8 * 4 + 1] = dmgPalette[(value >> 2) & 3];
326 video->palette[8 * 4 + 2] = dmgPalette[(value >> 4) & 3];
327 video->palette[8 * 4 + 3] = dmgPalette[(value >> 6) & 3];
328 video->renderer->writePalette(video->renderer, 8 * 4 + 0, video->palette[8 * 4 + 0]);
329 video->renderer->writePalette(video->renderer, 8 * 4 + 1, video->palette[8 * 4 + 1]);
330 video->renderer->writePalette(video->renderer, 8 * 4 + 2, video->palette[8 * 4 + 2]);
331 video->renderer->writePalette(video->renderer, 8 * 4 + 3, video->palette[8 * 4 + 3]);
332 break;
333 case REG_OBP1:
334 video->palette[9 * 4 + 0] = dmgPalette[value & 3];
335 video->palette[9 * 4 + 1] = dmgPalette[(value >> 2) & 3];
336 video->palette[9 * 4 + 2] = dmgPalette[(value >> 4) & 3];
337 video->palette[9 * 4 + 3] = dmgPalette[(value >> 6) & 3];
338 video->renderer->writePalette(video->renderer, 9 * 4 + 0, video->palette[9 * 4 + 0]);
339 video->renderer->writePalette(video->renderer, 9 * 4 + 1, video->palette[9 * 4 + 1]);
340 video->renderer->writePalette(video->renderer, 9 * 4 + 2, video->palette[9 * 4 + 2]);
341 video->renderer->writePalette(video->renderer, 9 * 4 + 3, video->palette[9 * 4 + 3]);
342 break;
343 }
344 } else {
345 switch (address) {
346 case REG_BCPD:
347 if (video->bcpIndex & 1) {
348 video->palette[video->bcpIndex >> 1] &= 0x00FF;
349 video->palette[video->bcpIndex >> 1] |= value << 8;
350 } else {
351 video->palette[video->bcpIndex >> 1] &= 0xFF00;
352 video->palette[video->bcpIndex >> 1] |= value;
353 }
354 video->renderer->writePalette(video->renderer, video->bcpIndex >> 1, video->palette[video->bcpIndex >> 1]);
355 if (video->bcpIncrement) {
356 ++video->bcpIndex;
357 video->bcpIndex &= 0x3F;
358 video->p->memory.io[REG_BCPS] &= 0x80;
359 video->p->memory.io[REG_BCPS] |= video->bcpIndex;
360 }
361 video->p->memory.io[REG_BCPD] = video->palette[video->bcpIndex >> 1] >> (8 * (video->bcpIndex & 1));
362 break;
363 case REG_OCPD:
364 if (video->ocpIndex & 1) {
365 video->palette[8 * 4 + (video->ocpIndex >> 1)] &= 0x00FF;
366 video->palette[8 * 4 + (video->ocpIndex >> 1)] |= value << 8;
367 } else {
368 video->palette[8 * 4 + (video->ocpIndex >> 1)] &= 0xFF00;
369 video->palette[8 * 4 + (video->ocpIndex >> 1)] |= value;
370 }
371 video->renderer->writePalette(video->renderer, 8 * 4 + (video->ocpIndex >> 1), video->palette[8 * 4 + (video->ocpIndex >> 1)]);
372 if (video->ocpIncrement) {
373 ++video->ocpIndex;
374 video->ocpIndex &= 0x3F;
375 video->p->memory.io[REG_OCPS] &= 0x80;
376 video->p->memory.io[REG_OCPS] |= video->ocpIndex;
377 }
378 video->p->memory.io[REG_OCPD] = video->palette[8 * 4 + (video->ocpIndex >> 1)] >> (8 * (video->ocpIndex & 1));
379 break;
380 }
381 }
382}
383
384void GBVideoSwitchBank(struct GBVideo* video, uint8_t value) {
385 value &= 1;
386 video->vramBank = &video->vram[value * GB_SIZE_VRAM_BANK0];
387 video->vramCurrentBank = value;
388}
389
390static void GBVideoDummyRendererInit(struct GBVideoRenderer* renderer, enum GBModel model) {
391 UNUSED(renderer);
392 UNUSED(model);
393 // Nothing to do
394}
395
396static void GBVideoDummyRendererDeinit(struct GBVideoRenderer* renderer) {
397 UNUSED(renderer);
398 // Nothing to do
399}
400
401static uint8_t GBVideoDummyRendererWriteVideoRegister(struct GBVideoRenderer* renderer, uint16_t address, uint8_t value) {
402 UNUSED(renderer);
403 UNUSED(address);
404 return value;
405}
406
407static void GBVideoDummyRendererWritePalette(struct GBVideoRenderer* renderer, int index, uint16_t value) {
408 UNUSED(renderer);
409 UNUSED(index);
410 UNUSED(value);
411}
412
413static void GBVideoDummyRendererDrawRange(struct GBVideoRenderer* renderer, int startX, int endX, int y, struct GBObj* obj, size_t oamMax) {
414 UNUSED(renderer);
415 UNUSED(endX);
416 UNUSED(startX);
417 UNUSED(y);
418 UNUSED(obj);
419 UNUSED(oamMax);
420 // Nothing to do
421}
422
423static void GBVideoDummyRendererFinishScanline(struct GBVideoRenderer* renderer, int y) {
424 UNUSED(renderer);
425 UNUSED(y);
426 // Nothing to do
427}
428
429static void GBVideoDummyRendererFinishFrame(struct GBVideoRenderer* renderer) {
430 UNUSED(renderer);
431 // Nothing to do
432}
433
434static void GBVideoDummyRendererGetPixels(struct GBVideoRenderer* renderer, unsigned* stride, const void** pixels) {
435 UNUSED(renderer);
436 UNUSED(stride);
437 UNUSED(pixels);
438 // Nothing to do
439}
440
441void GBVideoSerialize(const struct GBVideo* video, struct GBSerializedState* state) {
442 STORE_16LE(video->x, 0, &state->video.x);
443 STORE_16LE(video->ly, 0, &state->video.ly);
444 STORE_32LE(video->nextEvent, 0, &state->video.nextEvent);
445 STORE_32LE(video->eventDiff, 0, &state->video.eventDiff);
446 STORE_32LE(video->nextMode, 0, &state->video.nextMode);
447 STORE_32LE(video->dotCounter, 0, &state->video.dotCounter);
448 STORE_32LE(video->frameCounter, 0, &state->video.frameCounter);
449 state->video.vramCurrentBank = video->vramCurrentBank;
450
451 GBSerializedVideoFlags flags = 0;
452 flags = GBSerializedVideoFlagsSetBcpIncrement(flags, video->bcpIncrement);
453 flags = GBSerializedVideoFlagsSetOcpIncrement(flags, video->ocpIncrement);
454 state->video.flags = flags;
455 STORE_16LE(video->bcpIndex, 0, &state->video.bcpIndex);
456 STORE_16LE(video->ocpIndex, 0, &state->video.ocpIndex);
457
458 size_t i;
459 for (i = 0; i < 64; ++i) {
460 STORE_16LE(video->palette[i], i * 2, state->video.palette);
461 }
462
463 memcpy(state->vram, video->vram, GB_SIZE_VRAM);
464 memcpy(state->oam, &video->oam.raw, GB_SIZE_OAM);
465}
466
467void GBVideoDeserialize(struct GBVideo* video, const struct GBSerializedState* state) {
468 LOAD_16LE(video->x, 0, &state->video.x);
469 LOAD_16LE(video->ly, 0, &state->video.ly);
470 LOAD_32LE(video->nextEvent, 0, &state->video.nextEvent);
471 LOAD_32LE(video->eventDiff, 0, &state->video.eventDiff);
472 LOAD_32LE(video->nextMode, 0, &state->video.nextMode);
473 LOAD_32LE(video->dotCounter, 0, &state->video.dotCounter);
474 LOAD_32LE(video->frameCounter, 0, &state->video.frameCounter);
475 video->vramCurrentBank = state->video.vramCurrentBank;
476
477 GBSerializedVideoFlags flags = state->video.flags;
478 video->bcpIncrement = GBSerializedVideoFlagsGetBcpIncrement(flags);
479 video->ocpIncrement = GBSerializedVideoFlagsGetOcpIncrement(flags);
480 LOAD_16LE(video->bcpIndex, 0, &state->video.bcpIndex);
481 LOAD_16LE(video->ocpIndex, 0, &state->video.ocpIndex);
482
483 size_t i;
484 for (i = 0; i < 64; ++i) {
485 LOAD_16LE(video->palette[i], i * 2, state->video.palette);
486 video->renderer->writePalette(video->renderer, i, video->palette[i]);
487 }
488
489 memcpy(video->vram, state->vram, GB_SIZE_VRAM);
490 memcpy(&video->oam.raw, state->oam, GB_SIZE_OAM);
491
492 _cleanOAM(video, video->ly);
493 GBVideoSwitchBank(video, video->vramCurrentBank);
494}