all repos — mgba @ 5b8d64b0b5e5b3aa1edac7a98be6cbf471869dd0

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