all repos — mgba @ 1baa6fefbb49bea6c72cdffeda1f5f3ce50a1779

mGBA Game Boy Advance Emulator

src/gba/renderers/video-software.c (view raw)

  1/* Copyright (c) 2013-2015 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 "gba/renderers/software-private.h"
  7
  8#include <mgba/core/cache-set.h>
  9#include <mgba/internal/arm/macros.h>
 10#include <mgba/internal/gba/io.h>
 11#include <mgba/internal/gba/renderers/cache-set.h>
 12
 13#include <mgba-util/arm-algo.h>
 14#include <mgba-util/memory.h>
 15
 16#define DIRTY_SCANLINE(R, Y) R->scanlineDirty[Y >> 5] |= (1U << (Y & 0x1F))
 17#define CLEAN_SCANLINE(R, Y) R->scanlineDirty[Y >> 5] &= ~(1U << (Y & 0x1F))
 18
 19static void GBAVideoSoftwareRendererInit(struct GBAVideoRenderer* renderer);
 20static void GBAVideoSoftwareRendererDeinit(struct GBAVideoRenderer* renderer);
 21static void GBAVideoSoftwareRendererReset(struct GBAVideoRenderer* renderer);
 22static void GBAVideoSoftwareRendererWriteVRAM(struct GBAVideoRenderer* renderer, uint32_t address);
 23static void GBAVideoSoftwareRendererWriteOAM(struct GBAVideoRenderer* renderer, uint32_t oam);
 24static void GBAVideoSoftwareRendererWritePalette(struct GBAVideoRenderer* renderer, uint32_t address, uint16_t value);
 25static uint16_t GBAVideoSoftwareRendererWriteVideoRegister(struct GBAVideoRenderer* renderer, uint32_t address, uint16_t value);
 26static void GBAVideoSoftwareRendererDrawScanline(struct GBAVideoRenderer* renderer, int y);
 27static void GBAVideoSoftwareRendererFinishFrame(struct GBAVideoRenderer* renderer);
 28static void GBAVideoSoftwareRendererGetPixels(struct GBAVideoRenderer* renderer, size_t* stride, const void** pixels);
 29static void GBAVideoSoftwareRendererPutPixels(struct GBAVideoRenderer* renderer, size_t stride, const void* pixels);
 30
 31static void GBAVideoSoftwareRendererUpdateDISPCNT(struct GBAVideoSoftwareRenderer* renderer);
 32static void GBAVideoSoftwareRendererWriteBGCNT(struct GBAVideoSoftwareRenderer* renderer, struct GBAVideoSoftwareBackground* bg, uint16_t value);
 33static void GBAVideoSoftwareRendererWriteBGX_LO(struct GBAVideoSoftwareBackground* bg, uint16_t value);
 34static void GBAVideoSoftwareRendererWriteBGX_HI(struct GBAVideoSoftwareBackground* bg, uint16_t value);
 35static void GBAVideoSoftwareRendererWriteBGY_LO(struct GBAVideoSoftwareBackground* bg, uint16_t value);
 36static void GBAVideoSoftwareRendererWriteBGY_HI(struct GBAVideoSoftwareBackground* bg, uint16_t value);
 37static void GBAVideoSoftwareRendererWriteBLDCNT(struct GBAVideoSoftwareRenderer* renderer, uint16_t value);
 38
 39static void _drawScanline(struct GBAVideoSoftwareRenderer* renderer, int y);
 40
 41static void _updatePalettes(struct GBAVideoSoftwareRenderer* renderer);
 42
 43static void _breakWindow(struct GBAVideoSoftwareRenderer* softwareRenderer, struct WindowN* win, int y);
 44static void _breakWindowInner(struct GBAVideoSoftwareRenderer* softwareRenderer, struct WindowN* win);
 45
 46void GBAVideoSoftwareRendererCreate(struct GBAVideoSoftwareRenderer* renderer) {
 47	renderer->d.init = GBAVideoSoftwareRendererInit;
 48	renderer->d.reset = GBAVideoSoftwareRendererReset;
 49	renderer->d.deinit = GBAVideoSoftwareRendererDeinit;
 50	renderer->d.writeVideoRegister = GBAVideoSoftwareRendererWriteVideoRegister;
 51	renderer->d.writeVRAM = GBAVideoSoftwareRendererWriteVRAM;
 52	renderer->d.writeOAM = GBAVideoSoftwareRendererWriteOAM;
 53	renderer->d.writePalette = GBAVideoSoftwareRendererWritePalette;
 54	renderer->d.drawScanline = GBAVideoSoftwareRendererDrawScanline;
 55	renderer->d.finishFrame = GBAVideoSoftwareRendererFinishFrame;
 56	renderer->d.getPixels = GBAVideoSoftwareRendererGetPixels;
 57	renderer->d.putPixels = GBAVideoSoftwareRendererPutPixels;
 58
 59	renderer->d.disableBG[0] = false;
 60	renderer->d.disableBG[1] = false;
 61	renderer->d.disableBG[2] = false;
 62	renderer->d.disableBG[3] = false;
 63	renderer->d.disableOBJ = false;
 64	renderer->d.disableWIN[0] = false;
 65	renderer->d.disableWIN[1] = false;
 66	renderer->d.disableOBJWIN = false;
 67
 68	renderer->d.highlightBG[0] = false;
 69	renderer->d.highlightBG[1] = false;
 70	renderer->d.highlightBG[2] = false;
 71	renderer->d.highlightBG[3] = false;
 72	int i;
 73	for (i = 0; i < 128; ++i) {
 74		renderer->d.highlightOBJ[i] = false;
 75	}
 76	renderer->d.highlightColor = M_COLOR_WHITE;
 77	renderer->d.highlightAmount = 0;
 78
 79	renderer->temporaryBuffer = 0;
 80}
 81
 82static void GBAVideoSoftwareRendererInit(struct GBAVideoRenderer* renderer) {
 83	GBAVideoSoftwareRendererReset(renderer);
 84
 85	struct GBAVideoSoftwareRenderer* softwareRenderer = (struct GBAVideoSoftwareRenderer*) renderer;
 86
 87	int y;
 88	for (y = 0; y < GBA_VIDEO_VERTICAL_PIXELS; ++y) {
 89		color_t* row = &softwareRenderer->outputBuffer[softwareRenderer->outputBufferStride * y];
 90		int x;
 91		for (x = 0; x < GBA_VIDEO_HORIZONTAL_PIXELS; ++x) {
 92			row[x] = M_COLOR_WHITE;
 93		}
 94	}
 95}
 96
 97static void GBAVideoSoftwareRendererReset(struct GBAVideoRenderer* renderer) {
 98	struct GBAVideoSoftwareRenderer* softwareRenderer = (struct GBAVideoSoftwareRenderer*) renderer;
 99	int i;
100
101	softwareRenderer->dispcnt = 0x0080;
102
103	softwareRenderer->target1Obj = 0;
104	softwareRenderer->target1Bd = 0;
105	softwareRenderer->target2Obj = 0;
106	softwareRenderer->target2Bd = 0;
107	softwareRenderer->blendEffect = BLEND_NONE;
108	for (i = 0; i < 1024; i += 2) {
109		uint16_t entry;
110		LOAD_16(entry, i, softwareRenderer->d.palette);
111		GBAVideoSoftwareRendererWritePalette(renderer, i, entry);
112	}
113	softwareRenderer->blendDirty = false;
114	_updatePalettes(softwareRenderer);
115
116	softwareRenderer->blda = 0;
117	softwareRenderer->bldb = 0;
118	softwareRenderer->bldy = 0;
119
120	softwareRenderer->winN[0] = (struct WindowN) { .control = { .priority = 0 } };
121	softwareRenderer->winN[1] = (struct WindowN) { .control = { .priority = 1 } };
122	softwareRenderer->objwin = (struct WindowControl) { .priority = 2 };
123	softwareRenderer->winout = (struct WindowControl) { .priority = 3 };
124	softwareRenderer->oamDirty = 1;
125	softwareRenderer->oamMax = 0;
126
127	softwareRenderer->mosaic = 0;
128	softwareRenderer->greenswap = false;
129	softwareRenderer->nextY = 0;
130
131	softwareRenderer->objOffsetX = 0;
132	softwareRenderer->objOffsetY = 0;
133
134	memset(softwareRenderer->scanlineDirty, 0xFFFFFFFF, sizeof(softwareRenderer->scanlineDirty));
135	memset(softwareRenderer->cache, 0, sizeof(softwareRenderer->cache));
136	memset(softwareRenderer->nextIo, 0, sizeof(softwareRenderer->nextIo));
137
138	softwareRenderer->lastHighlightAmount = 0;
139
140	for (i = 0; i < 4; ++i) {
141		struct GBAVideoSoftwareBackground* bg = &softwareRenderer->bg[i];
142		bg->index = i;
143		bg->enabled = 0;
144		bg->priority = 0;
145		bg->charBase = 0;
146		bg->mosaic = 0;
147		bg->multipalette = 0;
148		bg->screenBase = 0;
149		bg->overflow = 0;
150		bg->size = 0;
151		bg->target1 = 0;
152		bg->target2 = 0;
153		bg->x = 0;
154		bg->y = 0;
155		bg->refx = 0;
156		bg->refy = 0;
157		bg->dx = 256;
158		bg->dmx = 0;
159		bg->dy = 0;
160		bg->dmy = 256;
161		bg->sx = 0;
162		bg->sy = 0;
163		bg->yCache = -1;
164		bg->offsetX = 0;
165		bg->offsetY = 0;
166	}
167}
168
169static void GBAVideoSoftwareRendererDeinit(struct GBAVideoRenderer* renderer) {
170	struct GBAVideoSoftwareRenderer* softwareRenderer = (struct GBAVideoSoftwareRenderer*) renderer;
171	UNUSED(softwareRenderer);
172}
173
174static uint16_t GBAVideoSoftwareRendererWriteVideoRegister(struct GBAVideoRenderer* renderer, uint32_t address, uint16_t value) {
175	struct GBAVideoSoftwareRenderer* softwareRenderer = (struct GBAVideoSoftwareRenderer*) renderer;
176	if (renderer->cache) {
177		GBAVideoCacheWriteVideoRegister(renderer->cache, address, value);
178	}
179
180	switch (address) {
181	case REG_DISPCNT:
182		value &= 0xFFF7;
183		softwareRenderer->dispcnt = value;
184		GBAVideoSoftwareRendererUpdateDISPCNT(softwareRenderer);
185		break;
186	case REG_GREENSWP:
187		softwareRenderer->greenswap = value & 1;
188		break;
189	case REG_BG0CNT:
190		value &= 0xDFFF;
191		GBAVideoSoftwareRendererWriteBGCNT(softwareRenderer, &softwareRenderer->bg[0], value);
192		break;
193	case REG_BG1CNT:
194		value &= 0xDFFF;
195		GBAVideoSoftwareRendererWriteBGCNT(softwareRenderer, &softwareRenderer->bg[1], value);
196		break;
197	case REG_BG2CNT:
198		value &= 0xFFFF;
199		GBAVideoSoftwareRendererWriteBGCNT(softwareRenderer, &softwareRenderer->bg[2], value);
200		break;
201	case REG_BG3CNT:
202		value &= 0xFFFF;
203		GBAVideoSoftwareRendererWriteBGCNT(softwareRenderer, &softwareRenderer->bg[3], value);
204		break;
205	case REG_BG0HOFS:
206		value &= 0x01FF;
207		softwareRenderer->bg[0].x = value;
208		break;
209	case REG_BG0VOFS:
210		value &= 0x01FF;
211		softwareRenderer->bg[0].y = value;
212		break;
213	case REG_BG1HOFS:
214		value &= 0x01FF;
215		softwareRenderer->bg[1].x = value;
216		break;
217	case REG_BG1VOFS:
218		value &= 0x01FF;
219		softwareRenderer->bg[1].y = value;
220		break;
221	case REG_BG2HOFS:
222		value &= 0x01FF;
223		softwareRenderer->bg[2].x = value;
224		break;
225	case REG_BG2VOFS:
226		value &= 0x01FF;
227		softwareRenderer->bg[2].y = value;
228		break;
229	case REG_BG3HOFS:
230		value &= 0x01FF;
231		softwareRenderer->bg[3].x = value;
232		break;
233	case REG_BG3VOFS:
234		value &= 0x01FF;
235		softwareRenderer->bg[3].y = value;
236		break;
237	case REG_BG2PA:
238		softwareRenderer->bg[2].dx = value;
239		break;
240	case REG_BG2PB:
241		softwareRenderer->bg[2].dmx = value;
242		break;
243	case REG_BG2PC:
244		softwareRenderer->bg[2].dy = value;
245		break;
246	case REG_BG2PD:
247		softwareRenderer->bg[2].dmy = value;
248		break;
249	case REG_BG2X_LO:
250		GBAVideoSoftwareRendererWriteBGX_LO(&softwareRenderer->bg[2], value);
251		if (softwareRenderer->bg[2].sx != softwareRenderer->cache[softwareRenderer->nextY].scale[0][0]) {
252			DIRTY_SCANLINE(softwareRenderer, softwareRenderer->nextY);
253		}
254		break;
255	case REG_BG2X_HI:
256		GBAVideoSoftwareRendererWriteBGX_HI(&softwareRenderer->bg[2], value);
257		if (softwareRenderer->bg[2].sx != softwareRenderer->cache[softwareRenderer->nextY].scale[0][0]) {
258			DIRTY_SCANLINE(softwareRenderer, softwareRenderer->nextY);
259		}
260		break;
261	case REG_BG2Y_LO:
262		GBAVideoSoftwareRendererWriteBGY_LO(&softwareRenderer->bg[2], value);
263		if (softwareRenderer->bg[2].sy != softwareRenderer->cache[softwareRenderer->nextY].scale[0][1]) {
264			DIRTY_SCANLINE(softwareRenderer, softwareRenderer->nextY);
265		}
266		break;
267	case REG_BG2Y_HI:
268		GBAVideoSoftwareRendererWriteBGY_HI(&softwareRenderer->bg[2], value);
269		if (softwareRenderer->bg[2].sy != softwareRenderer->cache[softwareRenderer->nextY].scale[0][1]) {
270			DIRTY_SCANLINE(softwareRenderer, softwareRenderer->nextY);
271		}
272		break;
273	case REG_BG3PA:
274		softwareRenderer->bg[3].dx = value;
275		break;
276	case REG_BG3PB:
277		softwareRenderer->bg[3].dmx = value;
278		break;
279	case REG_BG3PC:
280		softwareRenderer->bg[3].dy = value;
281		break;
282	case REG_BG3PD:
283		softwareRenderer->bg[3].dmy = value;
284		break;
285	case REG_BG3X_LO:
286		GBAVideoSoftwareRendererWriteBGX_LO(&softwareRenderer->bg[3], value);
287		if (softwareRenderer->bg[3].sx != softwareRenderer->cache[softwareRenderer->nextY].scale[1][0]) {
288			DIRTY_SCANLINE(softwareRenderer, softwareRenderer->nextY);
289		}
290		break;
291	case REG_BG3X_HI:
292		GBAVideoSoftwareRendererWriteBGX_HI(&softwareRenderer->bg[3], value);
293		if (softwareRenderer->bg[3].sx != softwareRenderer->cache[softwareRenderer->nextY].scale[1][0]) {
294			DIRTY_SCANLINE(softwareRenderer, softwareRenderer->nextY);
295		}
296		break;
297	case REG_BG3Y_LO:
298		GBAVideoSoftwareRendererWriteBGY_LO(&softwareRenderer->bg[3], value);
299		if (softwareRenderer->bg[3].sy != softwareRenderer->cache[softwareRenderer->nextY].scale[1][1]) {
300			DIRTY_SCANLINE(softwareRenderer, softwareRenderer->nextY);
301		}
302		break;
303	case REG_BG3Y_HI:
304		GBAVideoSoftwareRendererWriteBGY_HI(&softwareRenderer->bg[3], value);
305		if (softwareRenderer->bg[3].sy != softwareRenderer->cache[softwareRenderer->nextY].scale[1][1]) {
306			DIRTY_SCANLINE(softwareRenderer, softwareRenderer->nextY);
307		}
308		break;
309	case REG_BLDCNT:
310		GBAVideoSoftwareRendererWriteBLDCNT(softwareRenderer, value);
311		value &= 0x3FFF;
312		break;
313	case REG_BLDALPHA:
314		softwareRenderer->blda = value & 0x1F;
315		if (softwareRenderer->blda > 0x10) {
316			softwareRenderer->blda = 0x10;
317		}
318		softwareRenderer->bldb = (value >> 8) & 0x1F;
319		if (softwareRenderer->bldb > 0x10) {
320			softwareRenderer->bldb = 0x10;
321		}
322		value &= 0x1F1F;
323		break;
324	case REG_BLDY:
325		value &= 0x1F;
326		if (value > 0x10) {
327			value = 0x10;
328		}
329		if (softwareRenderer->bldy != value) {
330			softwareRenderer->bldy = value;
331			softwareRenderer->blendDirty = true;
332		}
333		break;
334	case REG_WIN0H:
335		softwareRenderer->winN[0].h.end = value;
336		softwareRenderer->winN[0].h.start = value >> 8;
337		if (softwareRenderer->winN[0].h.start > GBA_VIDEO_HORIZONTAL_PIXELS && softwareRenderer->winN[0].h.start > softwareRenderer->winN[0].h.end) {
338			softwareRenderer->winN[0].h.start = 0;
339		}
340		if (softwareRenderer->winN[0].h.end > GBA_VIDEO_HORIZONTAL_PIXELS) {
341			softwareRenderer->winN[0].h.end = GBA_VIDEO_HORIZONTAL_PIXELS;
342			if (softwareRenderer->winN[0].h.start > GBA_VIDEO_HORIZONTAL_PIXELS) {
343				softwareRenderer->winN[0].h.start = GBA_VIDEO_HORIZONTAL_PIXELS;
344			}
345		}
346		break;
347	case REG_WIN1H:
348		softwareRenderer->winN[1].h.end = value;
349		softwareRenderer->winN[1].h.start = value >> 8;
350		if (softwareRenderer->winN[1].h.start > GBA_VIDEO_HORIZONTAL_PIXELS && softwareRenderer->winN[1].h.start > softwareRenderer->winN[1].h.end) {
351			softwareRenderer->winN[1].h.start = 0;
352		}
353		if (softwareRenderer->winN[1].h.end > GBA_VIDEO_HORIZONTAL_PIXELS) {
354			softwareRenderer->winN[1].h.end = GBA_VIDEO_HORIZONTAL_PIXELS;
355			if (softwareRenderer->winN[1].h.start > GBA_VIDEO_HORIZONTAL_PIXELS) {
356				softwareRenderer->winN[1].h.start = GBA_VIDEO_HORIZONTAL_PIXELS;
357			}
358		}
359		break;
360	case REG_WIN0V:
361		softwareRenderer->winN[0].v.end = value;
362		softwareRenderer->winN[0].v.start = value >> 8;
363		if (softwareRenderer->winN[0].v.start > GBA_VIDEO_VERTICAL_PIXELS && softwareRenderer->winN[0].v.start > softwareRenderer->winN[0].v.end) {
364			softwareRenderer->winN[0].v.start = 0;
365		}
366		if (softwareRenderer->winN[0].v.end > GBA_VIDEO_VERTICAL_PIXELS) {
367			softwareRenderer->winN[0].v.end = GBA_VIDEO_VERTICAL_PIXELS;
368			if (softwareRenderer->winN[0].v.start > GBA_VIDEO_VERTICAL_PIXELS) {
369				softwareRenderer->winN[0].v.start = GBA_VIDEO_VERTICAL_PIXELS;
370			}
371		}
372		break;
373	case REG_WIN1V:
374		softwareRenderer->winN[1].v.end = value;
375		softwareRenderer->winN[1].v.start = value >> 8;
376		if (softwareRenderer->winN[1].v.start > GBA_VIDEO_VERTICAL_PIXELS && softwareRenderer->winN[1].v.start > softwareRenderer->winN[1].v.end) {
377			softwareRenderer->winN[1].v.start = 0;
378		}
379		if (softwareRenderer->winN[1].v.end > GBA_VIDEO_VERTICAL_PIXELS) {
380			softwareRenderer->winN[1].v.end = GBA_VIDEO_VERTICAL_PIXELS;
381			if (softwareRenderer->winN[1].v.start > GBA_VIDEO_VERTICAL_PIXELS) {
382				softwareRenderer->winN[1].v.start = GBA_VIDEO_VERTICAL_PIXELS;
383			}
384		}
385		break;
386	case REG_WININ:
387		value &= 0x3F3F;
388		softwareRenderer->winN[0].control.packed = value;
389		softwareRenderer->winN[1].control.packed = value >> 8;
390		break;
391	case REG_WINOUT:
392		value &= 0x3F3F;
393		softwareRenderer->winout.packed = value;
394		softwareRenderer->objwin.packed = value >> 8;
395		break;
396	case REG_MOSAIC:
397		softwareRenderer->mosaic = value;
398		break;
399	default:
400		mLOG(GBA_VIDEO, GAME_ERROR, "Invalid video register: 0x%03X", address);
401	}
402	softwareRenderer->nextIo[address >> 1] = value;
403	if (softwareRenderer->cache[softwareRenderer->nextY].io[address >> 1] != value) {
404		softwareRenderer->cache[softwareRenderer->nextY].io[address >> 1] = value;
405		DIRTY_SCANLINE(softwareRenderer, softwareRenderer->nextY);
406	}
407	return value;
408}
409
410static void GBAVideoSoftwareRendererWriteVRAM(struct GBAVideoRenderer* renderer, uint32_t address) {
411	struct GBAVideoSoftwareRenderer* softwareRenderer = (struct GBAVideoSoftwareRenderer*) renderer;
412	if (renderer->cache) {
413		mCacheSetWriteVRAM(renderer->cache, address);
414	}
415	memset(softwareRenderer->scanlineDirty, 0xFFFFFFFF, sizeof(softwareRenderer->scanlineDirty));
416	softwareRenderer->bg[0].yCache = -1;
417	softwareRenderer->bg[1].yCache = -1;
418	softwareRenderer->bg[2].yCache = -1;
419	softwareRenderer->bg[3].yCache = -1;
420}
421
422static void GBAVideoSoftwareRendererWriteOAM(struct GBAVideoRenderer* renderer, uint32_t oam) {
423	struct GBAVideoSoftwareRenderer* softwareRenderer = (struct GBAVideoSoftwareRenderer*) renderer;
424	UNUSED(oam);
425	softwareRenderer->oamDirty = 1;
426	memset(softwareRenderer->scanlineDirty, 0xFFFFFFFF, sizeof(softwareRenderer->scanlineDirty));
427}
428
429static void GBAVideoSoftwareRendererWritePalette(struct GBAVideoRenderer* renderer, uint32_t address, uint16_t value) {
430	struct GBAVideoSoftwareRenderer* softwareRenderer = (struct GBAVideoSoftwareRenderer*) renderer;
431	color_t color = mColorFrom555(value);
432	softwareRenderer->normalPalette[address >> 1] = color;
433	if (softwareRenderer->blendEffect == BLEND_BRIGHTEN) {
434		softwareRenderer->variantPalette[address >> 1] = _brighten(color, softwareRenderer->bldy);
435	} else if (softwareRenderer->blendEffect == BLEND_DARKEN) {
436		softwareRenderer->variantPalette[address >> 1] = _darken(color, softwareRenderer->bldy);
437	}
438	if (renderer->cache) {
439		mCacheSetWritePalette(renderer->cache, address >> 1, color);
440	}
441	memset(softwareRenderer->scanlineDirty, 0xFFFFFFFF, sizeof(softwareRenderer->scanlineDirty));
442}
443
444static void _breakWindow(struct GBAVideoSoftwareRenderer* softwareRenderer, struct WindowN* win, int y) {
445	if (win->v.end >= win->v.start) {
446		if (y >= win->v.end + win->offsetY) {
447			return;
448		}
449		if (y < win->v.start + win->offsetY) {
450			return;
451		}
452	} else if (y >= win->v.end + win->offsetY && y < win->v.start + win->offsetY) {
453		return;
454	}
455	if (win->h.end > GBA_VIDEO_HORIZONTAL_PIXELS || win->h.end < win->h.start) {
456		struct WindowN splits[2] = { *win, *win };
457		splits[0].h.start = 0;
458		splits[1].h.end = GBA_VIDEO_HORIZONTAL_PIXELS;
459		_breakWindowInner(softwareRenderer, &splits[0]);
460		_breakWindowInner(softwareRenderer, &splits[1]);
461	} else {
462		_breakWindowInner(softwareRenderer, win);
463	}
464}
465
466static void _breakWindowInner(struct GBAVideoSoftwareRenderer* softwareRenderer, struct WindowN* win) {
467	int activeWindow;
468	int startX = 0;
469	if (win->h.end > 0) {
470		for (activeWindow = 0; activeWindow < softwareRenderer->nWindows; ++activeWindow) {
471			if (win->h.start < softwareRenderer->windows[activeWindow].endX) {
472				// Insert a window before the end of the active window
473				struct Window oldWindow = softwareRenderer->windows[activeWindow];
474				if (win->h.start > startX) {
475					// And after the start of the active window
476					int nextWindow = softwareRenderer->nWindows;
477					++softwareRenderer->nWindows;
478					for (; nextWindow > activeWindow; --nextWindow) {
479						softwareRenderer->windows[nextWindow] = softwareRenderer->windows[nextWindow - 1];
480					}
481					softwareRenderer->windows[activeWindow].endX = win->h.start;
482					++activeWindow;
483				}
484				softwareRenderer->windows[activeWindow].control = win->control;
485				softwareRenderer->windows[activeWindow].endX = win->h.end;
486				if (win->h.end >= oldWindow.endX) {
487					// Trim off extra windows we've overwritten
488					for (++activeWindow; softwareRenderer->nWindows > activeWindow + 1 && win->h.end >= softwareRenderer->windows[activeWindow].endX; ++activeWindow) {
489						if (VIDEO_CHECKS && activeWindow >= MAX_WINDOW) {
490							mLOG(GBA_VIDEO, FATAL, "Out of bounds window write will occur");
491							return;
492						}
493						softwareRenderer->windows[activeWindow] = softwareRenderer->windows[activeWindow + 1];
494						--softwareRenderer->nWindows;
495					}
496				} else {
497					++activeWindow;
498					int nextWindow = softwareRenderer->nWindows;
499					++softwareRenderer->nWindows;
500					for (; nextWindow > activeWindow; --nextWindow) {
501						softwareRenderer->windows[nextWindow] = softwareRenderer->windows[nextWindow - 1];
502					}
503					softwareRenderer->windows[activeWindow] = oldWindow;
504				}
505				break;
506			}
507			startX = softwareRenderer->windows[activeWindow].endX;
508		}
509	}
510#ifdef DEBUG
511	if (softwareRenderer->nWindows > MAX_WINDOW) {
512		mLOG(GBA_VIDEO, FATAL, "Out of bounds window write occurred!");
513	}
514#endif
515}
516
517static void GBAVideoSoftwareRendererDrawScanline(struct GBAVideoRenderer* renderer, int y) {
518	struct GBAVideoSoftwareRenderer* softwareRenderer = (struct GBAVideoSoftwareRenderer*) renderer;
519
520	if (y == GBA_VIDEO_VERTICAL_PIXELS - 1) {
521		softwareRenderer->nextY = 0;
522	} else {
523		softwareRenderer->nextY = y + 1;
524	}
525
526	bool dirty = softwareRenderer->scanlineDirty[y >> 5] & (1U << (y & 0x1F));
527	if (memcmp(softwareRenderer->nextIo, softwareRenderer->cache[y].io, sizeof(softwareRenderer->nextIo))) {
528		memcpy(softwareRenderer->cache[y].io, softwareRenderer->nextIo, sizeof(softwareRenderer->nextIo));
529		dirty = true;
530	}
531
532	if (GBARegisterDISPCNTGetMode(softwareRenderer->dispcnt) != 0) {
533		if (softwareRenderer->cache[y].scale[0][0] != softwareRenderer->bg[2].sx ||
534		    softwareRenderer->cache[y].scale[0][1] != softwareRenderer->bg[2].sy ||
535		    softwareRenderer->cache[y].scale[1][0] != softwareRenderer->bg[3].sx ||
536		    softwareRenderer->cache[y].scale[1][1] != softwareRenderer->bg[3].sy) {
537			dirty = true;
538		}
539	}
540	softwareRenderer->cache[y].scale[0][0] = softwareRenderer->bg[2].sx;
541	softwareRenderer->cache[y].scale[0][1] = softwareRenderer->bg[2].sy;
542	softwareRenderer->cache[y].scale[1][0] = softwareRenderer->bg[3].sx;
543	softwareRenderer->cache[y].scale[1][1] = softwareRenderer->bg[3].sy;
544
545	if (!dirty) {
546		if (GBARegisterDISPCNTGetMode(softwareRenderer->dispcnt) != 0) {
547			softwareRenderer->bg[2].sx += softwareRenderer->bg[2].dmx;
548			softwareRenderer->bg[2].sy += softwareRenderer->bg[2].dmy;
549			softwareRenderer->bg[3].sx += softwareRenderer->bg[3].dmx;
550			softwareRenderer->bg[3].sy += softwareRenderer->bg[3].dmy;
551		}
552		return;
553	}
554
555	CLEAN_SCANLINE(softwareRenderer, y);
556
557	color_t* row = &softwareRenderer->outputBuffer[softwareRenderer->outputBufferStride * y];
558	if (GBARegisterDISPCNTIsForcedBlank(softwareRenderer->dispcnt)) {
559		int x;
560		for (x = 0; x < GBA_VIDEO_HORIZONTAL_PIXELS; ++x) {
561			row[x] = M_COLOR_WHITE;
562		}
563		return;
564	}
565
566	int x;
567	for (x = 0; x < GBA_VIDEO_HORIZONTAL_PIXELS; x += 4) {
568		softwareRenderer->spriteLayer[x] = FLAG_UNWRITTEN;
569		softwareRenderer->spriteLayer[x + 1] = FLAG_UNWRITTEN;
570		softwareRenderer->spriteLayer[x + 2] = FLAG_UNWRITTEN;
571		softwareRenderer->spriteLayer[x + 3] = FLAG_UNWRITTEN;
572	}
573
574	softwareRenderer->windows[0].endX = GBA_VIDEO_HORIZONTAL_PIXELS;
575	softwareRenderer->nWindows = 1;
576	if (GBARegisterDISPCNTIsWin0Enable(softwareRenderer->dispcnt) || GBARegisterDISPCNTIsWin1Enable(softwareRenderer->dispcnt) || GBARegisterDISPCNTIsObjwinEnable(softwareRenderer->dispcnt)) {
577		softwareRenderer->windows[0].control = softwareRenderer->winout;
578		if (GBARegisterDISPCNTIsWin1Enable(softwareRenderer->dispcnt) && !renderer->disableWIN[1]) {
579			_breakWindow(softwareRenderer, &softwareRenderer->winN[1], y);
580		}
581		if (GBARegisterDISPCNTIsWin0Enable(softwareRenderer->dispcnt) && !renderer->disableWIN[0]) {
582			_breakWindow(softwareRenderer, &softwareRenderer->winN[0], y);
583		}
584	} else {
585		softwareRenderer->windows[0].control.packed = 0xFF;
586	}
587
588	if (softwareRenderer->lastHighlightAmount != softwareRenderer->d.highlightAmount) {
589		softwareRenderer->lastHighlightAmount = softwareRenderer->d.highlightAmount;
590		if (softwareRenderer->lastHighlightAmount) {
591			softwareRenderer->blendDirty = true;
592		}
593	}
594
595	if (softwareRenderer->blendDirty) {
596		_updatePalettes(softwareRenderer);
597		softwareRenderer->blendDirty = false;
598	}
599	softwareRenderer->forceTarget1 = false;
600
601	int w;
602	x = 0;
603	for (w = 0; w < softwareRenderer->nWindows; ++w) {
604		// TOOD: handle objwin on backdrop
605		uint32_t backdrop = FLAG_UNWRITTEN | FLAG_PRIORITY | FLAG_IS_BACKGROUND;
606		if (!softwareRenderer->target1Bd || softwareRenderer->blendEffect == BLEND_NONE || softwareRenderer->blendEffect == BLEND_ALPHA || !GBAWindowControlIsBlendEnable(softwareRenderer->windows[w].control.packed)) {
607			backdrop |= softwareRenderer->normalPalette[0];
608		} else {
609			backdrop |= softwareRenderer->variantPalette[0];
610		}
611		int end = softwareRenderer->windows[w].endX;
612		for (; x < end - 3; x += 4) {
613			softwareRenderer->row[x] = backdrop;
614			softwareRenderer->row[x + 1] = backdrop;
615			softwareRenderer->row[x + 2] = backdrop;
616			softwareRenderer->row[x + 3] = backdrop;
617		}
618		for (; x < end; ++x) {
619			softwareRenderer->row[x] = backdrop;
620		}
621	}
622
623	softwareRenderer->bg[0].highlight = softwareRenderer->d.highlightBG[0];
624	softwareRenderer->bg[1].highlight = softwareRenderer->d.highlightBG[1];
625	softwareRenderer->bg[2].highlight = softwareRenderer->d.highlightBG[2];
626	softwareRenderer->bg[3].highlight = softwareRenderer->d.highlightBG[3];
627
628	_drawScanline(softwareRenderer, y);
629
630	if ((softwareRenderer->forceTarget1 || softwareRenderer->bg[0].target1 || softwareRenderer->bg[1].target1 || softwareRenderer->bg[2].target1 || softwareRenderer->bg[3].target1) && softwareRenderer->target2Bd) {
631		x = 0;
632		for (w = 0; w < softwareRenderer->nWindows; ++w) {
633			uint32_t backdrop = 0;
634			if (!softwareRenderer->target1Bd || softwareRenderer->blendEffect == BLEND_NONE || softwareRenderer->blendEffect == BLEND_ALPHA || !GBAWindowControlIsBlendEnable(softwareRenderer->windows[w].control.packed)) {
635				backdrop |= softwareRenderer->normalPalette[0];
636			} else {
637				backdrop |= softwareRenderer->variantPalette[0];
638			}
639			int end = softwareRenderer->windows[w].endX;
640			for (; x < end; ++x) {
641				uint32_t color = softwareRenderer->row[x];
642				if (color & FLAG_TARGET_1) {
643					softwareRenderer->row[x] = mColorMix5Bit(softwareRenderer->bldb, backdrop, softwareRenderer->blda, color);
644				}
645			}
646		}
647	}
648	if (softwareRenderer->forceTarget1 && (softwareRenderer->blendEffect == BLEND_DARKEN || softwareRenderer->blendEffect == BLEND_BRIGHTEN)) {
649		x = 0;
650		for (w = 0; w < softwareRenderer->nWindows; ++w) {
651			int end = softwareRenderer->windows[w].endX;
652			uint32_t mask = FLAG_REBLEND | FLAG_IS_BACKGROUND;
653			uint32_t match = FLAG_REBLEND;
654			bool objBlend = GBAWindowControlIsBlendEnable(softwareRenderer->objwin.packed);
655			bool winBlend = GBAWindowControlIsBlendEnable(softwareRenderer->windows[w].control.packed);
656			if (GBARegisterDISPCNTIsObjwinEnable(softwareRenderer->dispcnt) && objBlend != winBlend) {
657				mask |= FLAG_OBJWIN;
658				if (objBlend) {
659					match |= FLAG_OBJWIN;
660				}
661			} else if (!winBlend) {
662				x = end;
663				continue;
664			}
665			if (softwareRenderer->blendEffect == BLEND_DARKEN) {
666				for (; x < end; ++x) {
667					uint32_t color = softwareRenderer->row[x];
668					if ((color & mask) == match) {
669						softwareRenderer->row[x] = _darken(color, softwareRenderer->bldy);
670					}
671				}
672			} else if (softwareRenderer->blendEffect == BLEND_BRIGHTEN) {
673				for (; x < end; ++x) {
674					uint32_t color = softwareRenderer->row[x];
675					if ((color & mask) == match) {
676						softwareRenderer->row[x] = _brighten(color, softwareRenderer->bldy);
677					}
678				}
679			}
680		}
681	}
682
683	if (softwareRenderer->greenswap) {
684		for (x = 0; x < GBA_VIDEO_HORIZONTAL_PIXELS; x += 4) {
685			row[x] = softwareRenderer->row[x] & (M_COLOR_RED | M_COLOR_BLUE);
686			row[x] |= softwareRenderer->row[x + 1] & M_COLOR_GREEN;
687			row[x + 1] = softwareRenderer->row[x + 1] & (M_COLOR_RED | M_COLOR_BLUE);
688			row[x + 1] |= softwareRenderer->row[x] & M_COLOR_GREEN;
689			row[x + 2] = softwareRenderer->row[x + 2] & (M_COLOR_RED | M_COLOR_BLUE);
690			row[x + 2] |= softwareRenderer->row[x + 3] & M_COLOR_GREEN;
691			row[x + 3] = softwareRenderer->row[x + 3] & (M_COLOR_RED | M_COLOR_BLUE);
692			row[x + 3] |= softwareRenderer->row[x + 2] & M_COLOR_GREEN;
693
694		}
695	} else {
696#ifdef COLOR_16_BIT
697		for (x = 0; x < GBA_VIDEO_HORIZONTAL_PIXELS; x += 4) {
698			row[x] = softwareRenderer->row[x];
699			row[x + 1] = softwareRenderer->row[x + 1];
700			row[x + 2] = softwareRenderer->row[x + 2];
701			row[x + 3] = softwareRenderer->row[x + 3];
702		}
703#else
704		memcpy(row, softwareRenderer->row, GBA_VIDEO_HORIZONTAL_PIXELS * sizeof(*row));
705#endif
706	}
707}
708
709static void GBAVideoSoftwareRendererFinishFrame(struct GBAVideoRenderer* renderer) {
710	struct GBAVideoSoftwareRenderer* softwareRenderer = (struct GBAVideoSoftwareRenderer*) renderer;
711
712	softwareRenderer->nextY = 0;
713	if (softwareRenderer->temporaryBuffer) {
714		mappedMemoryFree(softwareRenderer->temporaryBuffer, GBA_VIDEO_HORIZONTAL_PIXELS * GBA_VIDEO_VERTICAL_PIXELS * 4);
715		softwareRenderer->temporaryBuffer = 0;
716	}
717	softwareRenderer->bg[2].sx = softwareRenderer->bg[2].refx;
718	softwareRenderer->bg[2].sy = softwareRenderer->bg[2].refy;
719	softwareRenderer->bg[3].sx = softwareRenderer->bg[3].refx;
720	softwareRenderer->bg[3].sy = softwareRenderer->bg[3].refy;
721
722	if (softwareRenderer->bg[0].enabled > 0) {
723		softwareRenderer->bg[0].enabled = 3;
724	}
725	if (softwareRenderer->bg[1].enabled > 0) {
726		softwareRenderer->bg[1].enabled = 3;
727	}
728	if (softwareRenderer->bg[2].enabled > 0) {
729		softwareRenderer->bg[2].enabled = 3;
730	}
731	if (softwareRenderer->bg[3].enabled > 0) {
732		softwareRenderer->bg[3].enabled = 3;
733	}
734}
735
736static void GBAVideoSoftwareRendererGetPixels(struct GBAVideoRenderer* renderer, size_t* stride, const void** pixels) {
737	struct GBAVideoSoftwareRenderer* softwareRenderer = (struct GBAVideoSoftwareRenderer*) renderer;
738	*stride = softwareRenderer->outputBufferStride;
739	*pixels = softwareRenderer->outputBuffer;
740}
741
742static void GBAVideoSoftwareRendererPutPixels(struct GBAVideoRenderer* renderer, size_t stride, const void* pixels) {
743	struct GBAVideoSoftwareRenderer* softwareRenderer = (struct GBAVideoSoftwareRenderer*) renderer;
744
745	const color_t* colorPixels = pixels;
746	unsigned i;
747	for (i = 0; i < GBA_VIDEO_VERTICAL_PIXELS; ++i) {
748		memmove(&softwareRenderer->outputBuffer[softwareRenderer->outputBufferStride * i], &colorPixels[stride * i], GBA_VIDEO_HORIZONTAL_PIXELS * BYTES_PER_PIXEL);
749	}
750}
751
752static void _enableBg(struct GBAVideoSoftwareRenderer* renderer, int bg, bool active) {
753	int wasActive = renderer->bg[bg].enabled;
754	if (!active) {
755		renderer->bg[bg].enabled = 0;
756	} else if (!wasActive && active) {
757		if (renderer->nextY == 0 || GBARegisterDISPCNTGetMode(renderer->dispcnt) > 2) {
758			// TODO: Investigate in more depth how switching background works in different modes
759			renderer->bg[bg].enabled = 3;
760		} else {
761			renderer->bg[bg].enabled = 1;
762		}
763	}
764}
765
766static void GBAVideoSoftwareRendererUpdateDISPCNT(struct GBAVideoSoftwareRenderer* renderer) {
767	_enableBg(renderer, 0, GBARegisterDISPCNTGetBg0Enable(renderer->dispcnt));
768	_enableBg(renderer, 1, GBARegisterDISPCNTGetBg1Enable(renderer->dispcnt));
769	_enableBg(renderer, 2, GBARegisterDISPCNTGetBg2Enable(renderer->dispcnt));
770	_enableBg(renderer, 3, GBARegisterDISPCNTGetBg3Enable(renderer->dispcnt));
771}
772
773static void GBAVideoSoftwareRendererWriteBGCNT(struct GBAVideoSoftwareRenderer* renderer, struct GBAVideoSoftwareBackground* bg, uint16_t value) {
774	UNUSED(renderer);
775	bg->priority = GBARegisterBGCNTGetPriority(value);
776	bg->charBase = GBARegisterBGCNTGetCharBase(value) << 14;
777	bg->mosaic = GBARegisterBGCNTGetMosaic(value);
778	bg->multipalette = GBARegisterBGCNTGet256Color(value);
779	bg->screenBase = GBARegisterBGCNTGetScreenBase(value) << 11;
780	bg->overflow = GBARegisterBGCNTGetOverflow(value);
781	bg->size = GBARegisterBGCNTGetSize(value);
782	bg->yCache = -1;
783}
784
785static void GBAVideoSoftwareRendererWriteBGX_LO(struct GBAVideoSoftwareBackground* bg, uint16_t value) {
786	bg->refx = (bg->refx & 0xFFFF0000) | value;
787	bg->sx = bg->refx;
788}
789
790static void GBAVideoSoftwareRendererWriteBGX_HI(struct GBAVideoSoftwareBackground* bg, uint16_t value) {
791	bg->refx = (bg->refx & 0x0000FFFF) | (value << 16);
792	bg->refx <<= 4;
793	bg->refx >>= 4;
794	bg->sx = bg->refx;
795}
796
797static void GBAVideoSoftwareRendererWriteBGY_LO(struct GBAVideoSoftwareBackground* bg, uint16_t value) {
798	bg->refy = (bg->refy & 0xFFFF0000) | value;
799	bg->sy = bg->refy;
800}
801
802static void GBAVideoSoftwareRendererWriteBGY_HI(struct GBAVideoSoftwareBackground* bg, uint16_t value) {
803	bg->refy = (bg->refy & 0x0000FFFF) | (value << 16);
804	bg->refy <<= 4;
805	bg->refy >>= 4;
806	bg->sy = bg->refy;
807}
808
809static void GBAVideoSoftwareRendererWriteBLDCNT(struct GBAVideoSoftwareRenderer* renderer, uint16_t value) {
810	enum GBAVideoBlendEffect oldEffect = renderer->blendEffect;
811
812	renderer->bg[0].target1 = GBARegisterBLDCNTGetTarget1Bg0(value);
813	renderer->bg[1].target1 = GBARegisterBLDCNTGetTarget1Bg1(value);
814	renderer->bg[2].target1 = GBARegisterBLDCNTGetTarget1Bg2(value);
815	renderer->bg[3].target1 = GBARegisterBLDCNTGetTarget1Bg3(value);
816	renderer->bg[0].target2 = GBARegisterBLDCNTGetTarget2Bg0(value);
817	renderer->bg[1].target2 = GBARegisterBLDCNTGetTarget2Bg1(value);
818	renderer->bg[2].target2 = GBARegisterBLDCNTGetTarget2Bg2(value);
819	renderer->bg[3].target2 = GBARegisterBLDCNTGetTarget2Bg3(value);
820
821	renderer->blendEffect = GBARegisterBLDCNTGetEffect(value);
822	renderer->target1Obj = GBARegisterBLDCNTGetTarget1Obj(value);
823	renderer->target1Bd = GBARegisterBLDCNTGetTarget1Bd(value);
824	renderer->target2Obj = GBARegisterBLDCNTGetTarget2Obj(value);
825	renderer->target2Bd = GBARegisterBLDCNTGetTarget2Bd(value);
826
827	if (oldEffect != renderer->blendEffect) {
828		renderer->blendDirty = true;
829	}
830}
831
832#define TEST_LAYER_ENABLED(X) \
833	!renderer->d.disableBG[X] && \
834	(renderer->bg[X].enabled == 3 && \
835	(GBAWindowControlIsBg ## X ## Enable(renderer->currentWindow.packed) || \
836	(GBARegisterDISPCNTIsObjwinEnable(renderer->dispcnt) && GBAWindowControlIsBg ## X ## Enable (renderer->objwin.packed))) && \
837	renderer->bg[X].priority == priority)
838
839static void _drawScanline(struct GBAVideoSoftwareRenderer* renderer, int y) {
840	int w;
841	int spriteLayers = 0;
842	if (GBARegisterDISPCNTIsObjEnable(renderer->dispcnt) && !renderer->d.disableOBJ) {
843		if (renderer->oamDirty) {
844			renderer->oamMax = GBAVideoRendererCleanOAM(renderer->d.oam->obj, renderer->sprites, renderer->objOffsetY);
845			renderer->oamDirty = false;
846		}
847		renderer->spriteCyclesRemaining = GBARegisterDISPCNTIsHblankIntervalFree(renderer->dispcnt) ? OBJ_HBLANK_FREE_LENGTH : OBJ_LENGTH;
848		int mosaicV = GBAMosaicControlGetObjV(renderer->mosaic) + 1;
849		int mosaicY = y - (y % mosaicV);
850		int i;
851		for (i = 0; i < renderer->oamMax; ++i) {
852			struct GBAVideoRendererSprite* sprite = &renderer->sprites[i];
853			int localY = y;
854			renderer->end = 0;
855			if ((y < sprite->y && (sprite->endY - 256 < 0 || y >= sprite->endY - 256)) || y >= sprite->endY) {
856				continue;
857			}
858			if (GBAObjAttributesAIsMosaic(sprite->obj.a) && mosaicV > 1) {
859				localY = mosaicY;
860				if (localY < sprite->y && sprite->y < GBA_VIDEO_VERTICAL_PIXELS) {
861					localY = sprite->y;
862				}
863				if (localY >= (sprite->endY & 0xFF)) {
864					localY = sprite->endY - 1;
865				}
866			}
867			for (w = 0; w < renderer->nWindows; ++w) {
868				renderer->currentWindow = renderer->windows[w].control;
869				renderer->start = renderer->end;
870				renderer->end = renderer->windows[w].endX;
871				// TODO: partial sprite drawing
872				if (!GBAWindowControlIsObjEnable(renderer->currentWindow.packed) && !GBARegisterDISPCNTIsObjwinEnable(renderer->dispcnt)) {
873					continue;
874				}
875
876				int drawn = GBAVideoSoftwareRendererPreprocessSprite(renderer, &sprite->obj, sprite->index, localY);
877				spriteLayers |= drawn << GBAObjAttributesCGetPriority(sprite->obj.c);
878			}
879			renderer->spriteCyclesRemaining -= sprite->cycles;
880			if (renderer->spriteCyclesRemaining <= 0) {
881				break;
882			}
883		}
884	}
885
886	unsigned priority;
887	for (priority = 0; priority < 4; ++priority) {
888		renderer->end = 0;
889		for (w = 0; w < renderer->nWindows; ++w) {
890			renderer->start = renderer->end;
891			renderer->end = renderer->windows[w].endX;
892			renderer->currentWindow = renderer->windows[w].control;
893			if (spriteLayers & (1 << priority)) {
894				GBAVideoSoftwareRendererPostprocessSprite(renderer, priority);
895			}
896			if (TEST_LAYER_ENABLED(0) && GBARegisterDISPCNTGetMode(renderer->dispcnt) < 2) {
897				GBAVideoSoftwareRendererDrawBackgroundMode0(renderer, &renderer->bg[0], y);
898			}
899			if (TEST_LAYER_ENABLED(1) && GBARegisterDISPCNTGetMode(renderer->dispcnt) < 2) {
900				GBAVideoSoftwareRendererDrawBackgroundMode0(renderer, &renderer->bg[1], y);
901			}
902			if (TEST_LAYER_ENABLED(2)) {
903				switch (GBARegisterDISPCNTGetMode(renderer->dispcnt)) {
904				case 0:
905					GBAVideoSoftwareRendererDrawBackgroundMode0(renderer, &renderer->bg[2], y);
906					break;
907				case 1:
908				case 2:
909					GBAVideoSoftwareRendererDrawBackgroundMode2(renderer, &renderer->bg[2], y);
910					break;
911				case 3:
912					GBAVideoSoftwareRendererDrawBackgroundMode3(renderer, &renderer->bg[2], y);
913					break;
914				case 4:
915					GBAVideoSoftwareRendererDrawBackgroundMode4(renderer, &renderer->bg[2], y);
916					break;
917				case 5:
918					GBAVideoSoftwareRendererDrawBackgroundMode5(renderer, &renderer->bg[2], y);
919					break;
920				}
921			}
922			if (TEST_LAYER_ENABLED(3)) {
923				switch (GBARegisterDISPCNTGetMode(renderer->dispcnt)) {
924				case 0:
925					GBAVideoSoftwareRendererDrawBackgroundMode0(renderer, &renderer->bg[3], y);
926					break;
927				case 2:
928					GBAVideoSoftwareRendererDrawBackgroundMode2(renderer, &renderer->bg[3], y);
929					break;
930				}
931			}
932		}
933	}
934	if (GBARegisterDISPCNTGetMode(renderer->dispcnt) != 0) {
935		renderer->bg[2].sx += renderer->bg[2].dmx;
936		renderer->bg[2].sy += renderer->bg[2].dmy;
937		renderer->bg[3].sx += renderer->bg[3].dmx;
938		renderer->bg[3].sy += renderer->bg[3].dmy;
939	}
940
941	if (renderer->bg[0].enabled > 0 && renderer->bg[0].enabled < 3) {
942		++renderer->bg[0].enabled;
943		DIRTY_SCANLINE(renderer, y);
944	}
945	if (renderer->bg[1].enabled > 0 && renderer->bg[1].enabled < 3) {
946		++renderer->bg[1].enabled;
947		DIRTY_SCANLINE(renderer, y);
948	}
949	if (renderer->bg[2].enabled > 0 && renderer->bg[2].enabled < 3) {
950		++renderer->bg[2].enabled;
951		DIRTY_SCANLINE(renderer, y);
952	}
953	if (renderer->bg[3].enabled > 0 && renderer->bg[3].enabled < 3) {
954		++renderer->bg[3].enabled;
955		DIRTY_SCANLINE(renderer, y);
956	}
957}
958
959static void _updatePalettes(struct GBAVideoSoftwareRenderer* renderer) {
960	int i;
961	if (renderer->blendEffect == BLEND_BRIGHTEN) {
962		for (i = 0; i < 512; ++i) {
963			renderer->variantPalette[i] = _brighten(renderer->normalPalette[i], renderer->bldy);
964		}
965	} else if (renderer->blendEffect == BLEND_DARKEN) {
966		for (i = 0; i < 512; ++i) {
967			renderer->variantPalette[i] = _darken(renderer->normalPalette[i], renderer->bldy);
968		}
969	} else {
970		for (i = 0; i < 512; ++i) {
971			renderer->variantPalette[i] = renderer->normalPalette[i];
972		}
973	}
974	unsigned highlightAmount = renderer->d.highlightAmount >> 4;
975
976	if (highlightAmount) {
977		for (i = 0; i < 512; ++i) {
978			renderer->highlightPalette[i] = mColorMix5Bit(0x10 - highlightAmount, renderer->normalPalette[i], highlightAmount, renderer->d.highlightColor);
979			renderer->highlightVariantPalette[i] = mColorMix5Bit(0x10 - highlightAmount, renderer->variantPalette[i], highlightAmount, renderer->d.highlightColor);
980		}
981	}
982}