all repos — mgba @ 965f2745398f08f115de731fbcf50d4be52a49ac

mGBA Game Boy Advance Emulator

src/gb/renderers/software.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 "software.h"
  7
  8#include "gb/io.h"
  9#include "util/memory.h"
 10
 11static void GBVideoSoftwareRendererInit(struct GBVideoRenderer* renderer, enum GBModel model);
 12static void GBVideoSoftwareRendererDeinit(struct GBVideoRenderer* renderer);
 13static uint8_t GBVideoSoftwareRendererWriteVideoRegister(struct GBVideoRenderer* renderer, uint16_t address, uint8_t value);
 14static void GBVideoSoftwareRendererWritePalette(struct GBVideoRenderer* renderer, int index, uint16_t value);
 15static void GBVideoSoftwareRendererDrawRange(struct GBVideoRenderer* renderer, int startX, int endX, int y, struct GBObj** obj, size_t oamMax);
 16static void GBVideoSoftwareRendererFinishScanline(struct GBVideoRenderer* renderer, int y);
 17static void GBVideoSoftwareRendererFinishFrame(struct GBVideoRenderer* renderer);
 18static void GBVideoSoftwareRendererGetPixels(struct GBVideoRenderer* renderer, unsigned* stride, const void** pixels);
 19static void GBVideoSoftwareRendererPutPixels(struct GBVideoRenderer* renderer, unsigned stride, void* pixels);
 20
 21static void GBVideoSoftwareRendererDrawBackground(struct GBVideoSoftwareRenderer* renderer, uint8_t* maps, int startX, int endX, int y, int sx, int sy);
 22static void GBVideoSoftwareRendererDrawObj(struct GBVideoSoftwareRenderer* renderer, struct GBObj* obj, int startX, int endX, int y);
 23
 24void GBVideoSoftwareRendererCreate(struct GBVideoSoftwareRenderer* renderer) {
 25	renderer->d.init = GBVideoSoftwareRendererInit;
 26	renderer->d.deinit = GBVideoSoftwareRendererDeinit;
 27	renderer->d.writeVideoRegister = GBVideoSoftwareRendererWriteVideoRegister;
 28	renderer->d.writePalette = GBVideoSoftwareRendererWritePalette,
 29	renderer->d.drawRange = GBVideoSoftwareRendererDrawRange;
 30	renderer->d.finishScanline = GBVideoSoftwareRendererFinishScanline;
 31	renderer->d.finishFrame = GBVideoSoftwareRendererFinishFrame;
 32	renderer->d.getPixels = GBVideoSoftwareRendererGetPixels;
 33	renderer->d.putPixels = 0;
 34
 35	renderer->temporaryBuffer = 0;
 36}
 37
 38static void GBVideoSoftwareRendererInit(struct GBVideoRenderer* renderer, enum GBModel model) {
 39	struct GBVideoSoftwareRenderer* softwareRenderer = (struct GBVideoSoftwareRenderer*) renderer;
 40	softwareRenderer->scy = 0;
 41	softwareRenderer->scx = 0;
 42	softwareRenderer->wy = 0;
 43	softwareRenderer->currentWy = 0;
 44	softwareRenderer->wx = 0;
 45	softwareRenderer->model = model;
 46
 47	int y;
 48	for (y = 0; y < GB_VIDEO_VERTICAL_PIXELS; ++y) {
 49		color_t* row = &softwareRenderer->outputBuffer[softwareRenderer->outputBufferStride * y];
 50		int x;
 51		for (x = 0; x < GB_VIDEO_HORIZONTAL_PIXELS; ++x) {
 52			row[x] = softwareRenderer->palette[0];
 53		}
 54	}
 55}
 56
 57static void GBVideoSoftwareRendererDeinit(struct GBVideoRenderer* renderer) {
 58	struct GBVideoSoftwareRenderer* softwareRenderer = (struct GBVideoSoftwareRenderer*) renderer;
 59	UNUSED(softwareRenderer);
 60}
 61
 62static uint8_t GBVideoSoftwareRendererWriteVideoRegister(struct GBVideoRenderer* renderer, uint16_t address, uint8_t value) {
 63	struct GBVideoSoftwareRenderer* softwareRenderer = (struct GBVideoSoftwareRenderer*) renderer;
 64	switch (address) {
 65	case REG_LCDC:
 66		softwareRenderer->lcdc = value;
 67		break;
 68	case REG_SCY:
 69		softwareRenderer->scy = value;
 70		break;
 71	case REG_SCX:
 72		softwareRenderer->scx = value;
 73		break;
 74	case REG_WY:
 75		softwareRenderer->wy = value;
 76		softwareRenderer->currentWy = value;
 77		break;
 78	case REG_WX:
 79		softwareRenderer->wx = value;
 80		break;
 81	}
 82	return value;
 83}
 84
 85static void GBVideoSoftwareRendererWritePalette(struct GBVideoRenderer* renderer, int index, uint16_t value) {
 86	struct GBVideoSoftwareRenderer* softwareRenderer = (struct GBVideoSoftwareRenderer*) renderer;
 87#ifdef COLOR_16_BIT
 88#ifdef COLOR_5_6_5
 89	color_t color = 0;
 90	color |= (value & 0x001F) << 11;
 91	color |= (value & 0x03E0) << 1;
 92	color |= (value & 0x7C00) >> 10;
 93#else
 94	color_t color = value;
 95#endif
 96#else
 97	color_t color = 0;
 98	color |= (value << 3) & 0xF8;
 99	color |= (value << 6) & 0xF800;
100	color |= (value << 9) & 0xF80000;
101#endif
102	softwareRenderer->palette[index] = color;
103}
104
105static void GBVideoSoftwareRendererDrawRange(struct GBVideoRenderer* renderer, int startX, int endX, int y, struct GBObj** obj, size_t oamMax) {
106	struct GBVideoSoftwareRenderer* softwareRenderer = (struct GBVideoSoftwareRenderer*) renderer;
107	uint8_t* maps = &softwareRenderer->d.vram[GB_BASE_MAP];
108	if (GBRegisterLCDCIsTileMap(softwareRenderer->lcdc)) {
109		maps += GB_SIZE_MAP;
110	}
111	if (GBRegisterLCDCIsBgEnable(softwareRenderer->lcdc)) {
112		GBVideoSoftwareRendererDrawBackground(softwareRenderer, maps, startX, endX, y, softwareRenderer->scx, softwareRenderer->scy);
113
114		if (GBRegisterLCDCIsWindow(softwareRenderer->lcdc) && softwareRenderer->wy <= y && endX >= softwareRenderer->wx - 7) {
115			maps = &softwareRenderer->d.vram[GB_BASE_MAP];
116			if (GBRegisterLCDCIsWindowTileMap(softwareRenderer->lcdc)) {
117				maps += GB_SIZE_MAP;
118			}
119			GBVideoSoftwareRendererDrawBackground(softwareRenderer, maps, softwareRenderer->wx - 7, endX, y, 7 - softwareRenderer->wx, (softwareRenderer->currentWy - y) - softwareRenderer->wy);
120		}
121	} else {
122		memset(&softwareRenderer->row[startX], 0, endX - startX);
123	}
124
125	if (GBRegisterLCDCIsObjEnable(softwareRenderer->lcdc)) {
126		size_t i;
127		for (i = 0; i < oamMax; ++i) {
128			GBVideoSoftwareRendererDrawObj(softwareRenderer, obj[i], startX, endX, y);
129		}
130	}
131	color_t* row = &softwareRenderer->outputBuffer[softwareRenderer->outputBufferStride * y];
132	int x;
133	for (x = startX; x < endX; x += 8) {
134		row[x] = softwareRenderer->palette[softwareRenderer->row[x]];
135		row[x + 1] = softwareRenderer->palette[softwareRenderer->row[x + 1]];
136		row[x + 2] = softwareRenderer->palette[softwareRenderer->row[x + 2]];
137		row[x + 3] = softwareRenderer->palette[softwareRenderer->row[x + 3]];
138		row[x + 4] = softwareRenderer->palette[softwareRenderer->row[x + 4]];
139		row[x + 5] = softwareRenderer->palette[softwareRenderer->row[x + 5]];
140		row[x + 6] = softwareRenderer->palette[softwareRenderer->row[x + 6]];
141		row[x + 7] = softwareRenderer->palette[softwareRenderer->row[x + 7]];
142	}
143}
144
145static void GBVideoSoftwareRendererFinishScanline(struct GBVideoRenderer* renderer, int y) {
146	struct GBVideoSoftwareRenderer* softwareRenderer = (struct GBVideoSoftwareRenderer*) renderer;
147	if (GBRegisterLCDCIsBgEnable(softwareRenderer->lcdc) && GBRegisterLCDCIsWindow(softwareRenderer->lcdc) && softwareRenderer->wy <= y && softwareRenderer->wx - 7 < GB_VIDEO_HORIZONTAL_PIXELS) {
148		++softwareRenderer->currentWy;
149	}
150}
151
152static void GBVideoSoftwareRendererFinishFrame(struct GBVideoRenderer* renderer) {
153	struct GBVideoSoftwareRenderer* softwareRenderer = (struct GBVideoSoftwareRenderer*) renderer;
154
155	if (softwareRenderer->temporaryBuffer) {
156		mappedMemoryFree(softwareRenderer->temporaryBuffer, GB_VIDEO_HORIZONTAL_PIXELS * GB_VIDEO_VERTICAL_PIXELS * 4);
157		softwareRenderer->temporaryBuffer = 0;
158	}
159	softwareRenderer->currentWy = softwareRenderer->wy;
160}
161
162static void GBVideoSoftwareRendererDrawBackground(struct GBVideoSoftwareRenderer* renderer, uint8_t* maps, int startX, int endX, int y, int sx, int sy) {
163	uint8_t* data = renderer->d.vram;
164	uint8_t* attr = &maps[GB_SIZE_VRAM_BANK0];
165	if (!GBRegisterLCDCIsTileData(renderer->lcdc)) {
166		data += 0x1000;
167	}
168	int topY = (((y + sy) >> 3) & 0x1F) * 0x20;
169	int bottomY = (y + sy) & 7;
170	if (startX < 0) {
171		startX = 0;
172	}
173	int x;
174	if ((startX + sx) & 7) {
175		int startX2 = startX + 8 - ((startX + sx) & 7);
176		for (x = startX; x < startX2; ++x) {
177			uint8_t* localData = data;
178			int localY = bottomY;
179			int topX = ((x + sx) >> 3) & 0x1F;
180			int bottomX = 7 - ((x + sx) & 7);
181			int bgTile;
182			if (GBRegisterLCDCIsTileData(renderer->lcdc)) {
183				bgTile = maps[topX + topY];
184			} else {
185				bgTile = ((int8_t*) maps)[topX + topY];
186			}
187			int p = 0;
188			if (renderer->model >= GB_MODEL_CGB) {
189				GBObjAttributes attrs = attr[topX + topY];
190				p = GBObjAttributesGetCGBPalette(attrs) * 4;
191				if (GBObjAttributesIsBank(attrs)) {
192					localData += GB_SIZE_VRAM_BANK0;
193				}
194				if (GBObjAttributesIsYFlip(attrs)) {
195					localY = 7 - bottomY;
196				}
197				if (GBObjAttributesIsXFlip(attrs)) {
198					bottomX = 7 - bottomX;
199					bottomX = 7 - bottomX;
200				}
201			}
202			uint8_t tileDataLower = data[(bgTile * 8 + localY) * 2];
203			uint8_t tileDataUpper = data[(bgTile * 8 + localY) * 2 + 1];
204			tileDataUpper >>= bottomX;
205			tileDataLower >>= bottomX;
206			renderer->row[x] = p | ((tileDataUpper & 1) << 1) | (tileDataLower & 1);
207		}
208		startX = startX2;
209	}
210	for (x = startX; x < endX; x += 8) {
211		uint8_t* localData = data;
212		int localY = bottomY;
213		int topX = ((x + sx) >> 3) & 0x1F;
214		int bgTile;
215		if (GBRegisterLCDCIsTileData(renderer->lcdc)) {
216			bgTile = maps[topX + topY];
217		} else {
218			bgTile = ((int8_t*) maps)[topX + topY];
219		}
220		int p = 0;
221		if (renderer->model >= GB_MODEL_CGB) {
222			GBObjAttributes attrs = attr[topX + topY];
223			p = GBObjAttributesGetCGBPalette(attrs) * 4;
224			if (GBObjAttributesIsBank(attrs)) {
225				localData += GB_SIZE_VRAM_BANK0;
226			}
227			if (GBObjAttributesIsYFlip(attrs)) {
228				localY = 7 - bottomY;
229			}
230			if (GBObjAttributesIsXFlip(attrs)) {
231				uint8_t tileDataLower = localData[(bgTile * 8 + localY) * 2];
232				uint8_t tileDataUpper = localData[(bgTile * 8 + localY) * 2 + 1];
233				renderer->row[x + 0] = p | ((tileDataUpper & 1) << 1) | (tileDataLower & 1);
234				renderer->row[x + 1] = p | (tileDataUpper & 2) | ((tileDataLower & 2) >> 1);
235				renderer->row[x + 2] = p | ((tileDataUpper & 4) >> 1) | ((tileDataLower & 4) >> 2);
236				renderer->row[x + 3] = p | ((tileDataUpper & 8) >> 2) | ((tileDataLower & 8) >> 3);
237				renderer->row[x + 4] = p | ((tileDataUpper & 16) >> 3) | ((tileDataLower & 16) >> 4);
238				renderer->row[x + 5] = p | ((tileDataUpper & 32) >> 4) | ((tileDataLower & 32) >> 5);
239				renderer->row[x + 6] = p | ((tileDataUpper & 64) >> 5) | ((tileDataLower & 64) >> 6);
240				renderer->row[x + 7] = p | ((tileDataUpper & 128) >> 6) | ((tileDataLower & 128) >> 7);
241				continue;
242			}
243		}
244		uint8_t tileDataLower = localData[(bgTile * 8 + localY) * 2];
245		uint8_t tileDataUpper = localData[(bgTile * 8 + localY) * 2 + 1];
246		renderer->row[x + 7] = p | ((tileDataUpper & 1) << 1) | (tileDataLower & 1);
247		renderer->row[x + 6] = p | (tileDataUpper & 2) | ((tileDataLower & 2) >> 1);
248		renderer->row[x + 5] = p | ((tileDataUpper & 4) >> 1) | ((tileDataLower & 4) >> 2);
249		renderer->row[x + 4] = p | ((tileDataUpper & 8) >> 2) | ((tileDataLower & 8) >> 3);
250		renderer->row[x + 3] = p | ((tileDataUpper & 16) >> 3) | ((tileDataLower & 16) >> 4);
251		renderer->row[x + 2] = p | ((tileDataUpper & 32) >> 4) | ((tileDataLower & 32) >> 5);
252		renderer->row[x + 1] = p | ((tileDataUpper & 64) >> 5) | ((tileDataLower & 64) >> 6);
253		renderer->row[x + 0] = p | ((tileDataUpper & 128) >> 6) | ((tileDataLower & 128) >> 7);
254	}
255}
256
257static void GBVideoSoftwareRendererDrawObj(struct GBVideoSoftwareRenderer* renderer, struct GBObj* obj, int startX, int endX, int y) {
258	int ix = obj->x - 8;
259	if (endX < ix || startX >= ix + 8) {
260		return;
261	}
262	if (obj->x < endX) {
263		endX = obj->x;
264	}
265	if (obj->x - 8 > startX) {
266		startX = obj->x - 8;
267	}
268	if (startX < 0) {
269		startX = 0;
270	}
271	uint8_t* data = renderer->d.vram;
272	int tileOffset = 0;
273	int bottomY;
274	if (GBObjAttributesIsYFlip(obj->attr)) {
275		bottomY = 7 - ((y - obj->y - 16) & 7);
276		if (GBRegisterLCDCIsObjSize(renderer->lcdc) && y - obj->y < -8) {
277			++tileOffset;
278		}
279	} else {
280		bottomY = (y - obj->y - 16) & 7;
281		if (GBRegisterLCDCIsObjSize(renderer->lcdc) && y - obj->y >= -8) {
282			++tileOffset;
283		}
284	}
285	uint8_t mask = GBObjAttributesIsPriority(obj->attr) ? ~0x1C : ~0x3F;
286	int p;
287	if (renderer->model >= GB_MODEL_CGB) {
288		p = (GBObjAttributesGetCGBPalette(obj->attr) + 8) * 4;
289		if (GBObjAttributesIsBank(obj->attr)) {
290			data += GB_SIZE_VRAM_BANK0;
291		}
292	} else {
293		p = (GBObjAttributesGetPalette(obj->attr) + 8) * 4;
294	}
295	int bottomX;
296	int x;
297	for (x = startX; x < endX; ++x) {
298		if (GBObjAttributesIsXFlip(obj->attr)) {
299			bottomX = (x - obj->x) & 7;
300		} else {
301			bottomX = 7 - ((x - obj->x) & 7);
302		}
303		int objTile = obj->tile + tileOffset;
304		uint8_t tileDataLower = data[(objTile * 8 + bottomY) * 2];
305		uint8_t tileDataUpper = data[(objTile * 8 + bottomY) * 2 + 1];
306		tileDataUpper >>= bottomX;
307		tileDataLower >>= bottomX;
308		color_t current = renderer->row[x];
309		if (((tileDataUpper | tileDataLower) & 1) && !(current & mask)) {
310			renderer->row[x] = p | ((tileDataUpper & 1) << 1) | (tileDataLower & 1);
311		}
312	}
313}
314
315static void GBVideoSoftwareRendererGetPixels(struct GBVideoRenderer* renderer, unsigned* stride, const void** pixels) {
316	struct GBVideoSoftwareRenderer* softwareRenderer = (struct GBVideoSoftwareRenderer*) renderer;
317	// TODO: Share with GBAVideoSoftwareRendererGetPixels
318#ifdef COLOR_16_BIT
319	*stride = GB_VIDEO_HORIZONTAL_PIXELS;
320	if (!softwareRenderer->temporaryBuffer) {
321		softwareRenderer->temporaryBuffer = anonymousMemoryMap(GB_VIDEO_HORIZONTAL_PIXELS * GB_VIDEO_VERTICAL_PIXELS * 4);
322	}
323	*pixels = softwareRenderer->temporaryBuffer;
324	unsigned y, x;
325	for (y = 0; y < GB_VIDEO_VERTICAL_PIXELS; ++y) {
326		for (x = 0; x < GB_VIDEO_HORIZONTAL_PIXELS; ++x) {
327			color_t inColor = softwareRenderer->outputBuffer[softwareRenderer->outputBufferStride * y + x];
328			uint32_t outColor;
329#ifdef COLOR_5_6_5
330			outColor = (inColor & 0x1F) << 19;
331			outColor |= (inColor & 0x7C0) << 5;
332			outColor |= (inColor & 0xF800) >> 8;
333#else
334			outColor = (inColor & 0x1F) << 3;
335			outColor |= (inColor & 0x3E0) << 6;
336			outColor |= (inColor & 0x7C00) << 9;
337#endif
338			softwareRenderer->temporaryBuffer[GB_VIDEO_HORIZONTAL_PIXELS * y + x] = outColor;
339		}
340	}
341#else
342	*stride = softwareRenderer->outputBufferStride;
343	*pixels = softwareRenderer->outputBuffer;
344#endif
345}