all repos — mgba @ c15dedf3f44f76abe87a40fe02db6f9a26f80123

mGBA Game Boy Advance Emulator

src/gba/renderers/gl.c (view raw)

   1/* Copyright (c) 2013-2019 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 <mgba/internal/gba/renderers/gl.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
  13static void GBAVideoGLRendererInit(struct GBAVideoRenderer* renderer);
  14static void GBAVideoGLRendererDeinit(struct GBAVideoRenderer* renderer);
  15static void GBAVideoGLRendererReset(struct GBAVideoRenderer* renderer);
  16static void GBAVideoGLRendererWriteVRAM(struct GBAVideoRenderer* renderer, uint32_t address);
  17static void GBAVideoGLRendererWriteOAM(struct GBAVideoRenderer* renderer, uint32_t oam);
  18static void GBAVideoGLRendererWritePalette(struct GBAVideoRenderer* renderer, uint32_t address, uint16_t value);
  19static uint16_t GBAVideoGLRendererWriteVideoRegister(struct GBAVideoRenderer* renderer, uint32_t address, uint16_t value);
  20static void GBAVideoGLRendererDrawScanline(struct GBAVideoRenderer* renderer, int y);
  21static void GBAVideoGLRendererFinishFrame(struct GBAVideoRenderer* renderer);
  22static void GBAVideoGLRendererGetPixels(struct GBAVideoRenderer* renderer, size_t* stride, const void** pixels);
  23static void GBAVideoGLRendererPutPixels(struct GBAVideoRenderer* renderer, size_t stride, const void* pixels);
  24
  25static void GBAVideoGLRendererUpdateDISPCNT(struct GBAVideoGLRenderer* renderer);
  26static void GBAVideoGLRendererWriteBGCNT(struct GBAVideoGLBackground* bg, uint16_t value);
  27static void GBAVideoGLRendererWriteBGX_LO(struct GBAVideoGLBackground* bg, uint16_t value);
  28static void GBAVideoGLRendererWriteBGX_HI(struct GBAVideoGLBackground* bg, uint16_t value);
  29static void GBAVideoGLRendererWriteBGY_LO(struct GBAVideoGLBackground* bg, uint16_t value);
  30static void GBAVideoGLRendererWriteBGY_HI(struct GBAVideoGLBackground* bg, uint16_t value);
  31static void GBAVideoGLRendererWriteBLDCNT(struct GBAVideoGLRenderer* renderer, uint16_t value);
  32
  33static void GBAVideoGLRendererDrawSprite(struct GBAVideoGLRenderer* renderer, struct GBAObj* sprite, int y, int spriteY);
  34static void GBAVideoGLRendererDrawBackgroundMode0(struct GBAVideoGLRenderer* renderer, struct GBAVideoGLBackground* background, int y);
  35static void GBAVideoGLRendererDrawBackgroundMode2(struct GBAVideoGLRenderer* renderer, struct GBAVideoGLBackground* background, int y);
  36static void GBAVideoGLRendererDrawBackgroundMode3(struct GBAVideoGLRenderer* renderer, struct GBAVideoGLBackground* background, int y);
  37static void GBAVideoGLRendererDrawBackgroundMode4(struct GBAVideoGLRenderer* renderer, struct GBAVideoGLBackground* background, int y);
  38static void GBAVideoGLRendererDrawBackgroundMode5(struct GBAVideoGLRenderer* renderer, struct GBAVideoGLBackground* background, int y);
  39
  40static void _compositeLayer(struct GBAVideoGLRenderer* renderer, GLuint tex, GLuint flags, int y);
  41
  42#define TEST_LAYER_ENABLED(X) !renderer->disableBG[X] && glRenderer->bg[X].enabled == 4 && glRenderer->bg[X].priority == priority
  43
  44static const GLchar* const _gl3Header =
  45	"#version 130\n";
  46
  47static const char* const _vertexShader =
  48	"attribute vec2 position;\n"
  49	"uniform ivec2 loc;\n"
  50	"uniform ivec2 maxPos;\n"
  51	"varying vec2 texCoord;\n"
  52
  53	"void main() {\n"
  54	"	vec2 local = vec2(position.x, float(position.y * loc.x + loc.y) / abs(maxPos.y));\n"
  55	"	gl_Position = vec4((local * 2. - 1.) * sign(maxPos), 0., 1.);\n"
  56	"	texCoord = local * abs(maxPos);\n"
  57	"}";
  58
  59static const char* const _renderTile16 =
  60	"vec4 renderTile(int tile, int paletteId, ivec2 localCoord) {\n"
  61	"	int address = charBase + tile * 16 + (localCoord.x >> 2) + (localCoord.y << 1);\n"
  62	"	vec4 halfrow = texelFetch(vram, ivec2(address & 255, address >> 8), 0);\n"
  63	"	int entry = int(halfrow[3 - (localCoord.x & 3)] * 15.9);\n"
  64	"	vec4 color = texelFetch(palette, ivec2(entry, paletteId), 0);\n"
  65	"	if (entry == 0) {\n"
  66	"		discard;\n"
  67	"	}\n"
  68	"	color.a = 1;\n"
  69	"	return color;\n"
  70	"}";
  71
  72static const char* const _renderTile256 =
  73	"vec4 renderTile(int tile, int paletteId, ivec2 localCoord) {\n"
  74	"	int address = charBase + tile * 32 + (localCoord.x >> 1) + (localCoord.y << 2);\n"
  75	"	vec4 halfrow = texelFetch(vram, ivec2(address & 255, address >> 8), 0);\n"
  76	"	int entry = int(halfrow[3 - 2 * (localCoord.x & 1)] * 15.9);\n"
  77	"	int pal2 = int(halfrow[2 - 2 * (localCoord.x & 1)] * 15.9);\n"
  78	"	vec4 color = texelFetch(palette, ivec2(entry, pal2 + (paletteId & 16)), 0);\n"
  79	"	if ((pal2 | entry) == 0) {\n"
  80	"		discard;\n"
  81	"	}\n"
  82	"	color.a = 1.;\n"
  83	"	return color;\n"
  84	"}";
  85
  86static const char* const _renderMode0 =
  87	"varying vec2 texCoord;\n"
  88	"uniform sampler2D vram;\n"
  89	"uniform sampler2D palette;\n"
  90	"uniform int screenBase;\n"
  91	"uniform int charBase;\n"
  92	"uniform int size;\n"
  93	"uniform ivec2 offset;\n"
  94	"uniform ivec3 inflags;\n"
  95	"out vec4 color;\n"
  96	"out vec3 flags;\n"
  97	"const vec3 flagCoeff = vec3(32., 8., 4.);\n"
  98
  99	"vec4 renderTile(int tile, int paletteId, ivec2 localCoord);\n"
 100
 101	"void main() {\n"
 102	"	ivec2 coord = ivec2(texCoord) + offset;\n"
 103	"	if ((size & 1) == 1) {\n"
 104	"		coord.y += coord.x & 256;\n"
 105	"	}\n"
 106	"	coord.x &= 255;\n"
 107	"	int mapAddress = screenBase + (coord.x >> 3) + (coord.y >> 3) * 32;\n"
 108	"	vec4 map = texelFetch(vram, ivec2(mapAddress & 255, mapAddress >> 8), 0);\n"
 109	"	int tileFlags = int(map.g * 15.9);\n"
 110	"	if ((tileFlags & 4) == 4) {\n"
 111	"		coord.x ^= 7;\n"
 112	"	}\n"
 113	"	if ((tileFlags & 8) == 8) {\n"
 114	"		coord.y ^= 7;\n"
 115	"	}\n"
 116	"	int tile = int(map.a * 15.9) + int(map.b * 15.9) * 16 + (tileFlags & 0x3) * 256;\n"
 117	"	color = renderTile(tile, int(map.r * 15.9), coord & 7);\n"
 118	"	flags = inflags / flagCoeff;\n"
 119	"}";
 120
 121static const char* const _fetchTileOverflow =
 122	"vec4 fetchTile(ivec2 coord) {\n"
 123	"	int sizeAdjusted = (0x8000 << size) - 1;\n"
 124	"	coord &= sizeAdjusted;\n"
 125	"	return renderTile(coord);\n"
 126	"}";
 127
 128static const char* const _fetchTileNoOverflow =
 129	"vec4 fetchTile(ivec2 coord) {\n"
 130	"	int sizeAdjusted = (0x8000 << size) - 1;\n"
 131	"	ivec2 outerCoord = coord & ~sizeAdjusted;\n"
 132	"	if ((outerCoord.x | outerCoord.y) != 0) {\n"
 133	"		discard;\n"
 134	"	}\n"
 135	"	return renderTile(coord);\n"
 136	"}";
 137
 138static const char* const _renderMode2 =
 139	"varying vec2 texCoord;\n"
 140	"uniform sampler2D vram;\n"
 141	"uniform sampler2D palette;\n"
 142	"uniform int screenBase;\n"
 143	"uniform int charBase;\n"
 144	"uniform int size;\n"
 145	"uniform ivec3 inflags;\n"
 146	"uniform ivec2[4] offset;\n"
 147	"uniform ivec2[4] transform;\n"
 148	"out vec4 color;\n"
 149	"out vec3 flags;\n"
 150	"const vec3 flagCoeff = vec3(32., 8., 4.);\n"
 151	"precision highp float;\n"
 152	"precision highp int;\n"
 153
 154	"vec4 fetchTile(ivec2 coord);\n"
 155
 156	"vec4 renderTile(ivec2 coord) {\n"
 157	"	int map = (coord.x >> 11) + (((coord.y >> 7) & 0x7F0) << size);\n"
 158	"	int mapAddress = screenBase + (map >> 1);\n"
 159	"	vec4 twomaps = texelFetch(vram, ivec2(mapAddress & 255, mapAddress >> 8), 0);\n"
 160	"	int tile = int(twomaps[3 - 2 * (map & 1)] * 15.9) + int(twomaps[2 - 2 * (map & 1)] * 15.9) * 16;\n"
 161	"	int address = charBase + tile * 32 + ((coord.x >> 9) & 3) + ((coord.y >> 6) & 0x1C);\n"
 162	"	vec4 halfrow = texelFetch(vram, ivec2(address & 255, address >> 8), 0);\n"
 163	"	int entry = int(halfrow[3 - ((coord.x >> 7) & 2)] * 15.9);\n"
 164	"	int pal2 = int(halfrow[2 - ((coord.x >> 7) & 2)] * 15.9);\n"
 165	"	vec4 color = texelFetch(palette, ivec2(entry, pal2), 0);\n"
 166	"	if ((pal2 | entry) == 0) {\n"
 167	"		discard;\n"
 168	"	}\n"
 169	"	color.a = 1.;\n"
 170	"	return color;\n"
 171	"}\n"
 172
 173	"vec2 interpolate(ivec2 arr[4], float x) {\n"
 174	"	float x1m = 1. - x;\n"
 175	"	return x1m * x1m * x1m * arr[0] +"
 176		"  3 * x1m * x1m * x   * arr[1] +"
 177		"  3 * x1m * x   * x   * arr[2] +"
 178		"      x   * x   * x   * arr[3];\n"
 179	"}\n"
 180
 181	"void main() {\n"
 182	"	float y = fract(texCoord.y);\n"
 183	"	float lin = 0.5 - y / ceil(y) * 0.25;\n"
 184	"	vec2 mixedTransform = interpolate(transform, lin);\n"
 185	"	vec2 mixedOffset = interpolate(offset, lin);\n"
 186	"	color = fetchTile(ivec2(mixedTransform * texCoord.x + mixedOffset));\n"
 187	"	flags = inflags / flagCoeff;\n"
 188	"}";
 189
 190static const char* const _renderObj =
 191	"varying vec2 texCoord;\n"
 192	"uniform sampler2D vram;\n"
 193	"uniform sampler2D palette;\n"
 194	"uniform int charBase;\n"
 195	"uniform int stride;\n"
 196	"uniform int localPalette;\n"
 197	"uniform ivec3 inflags;\n"
 198	"uniform mat2x2 transform;\n"
 199	"uniform ivec4 dims;\n"
 200	"out vec4 color;\n"
 201	"out vec3 flags;\n"
 202	"const vec3 flagCoeff = vec3(32., 8., 4.);\n"
 203
 204	"vec4 renderTile(int tile, int paletteId, ivec2 localCoord);\n"
 205
 206	"void main() {\n"
 207	"	ivec2 coord = ivec2(transform * (texCoord - dims.zw / 2) + dims.xy / 2);\n"
 208	"	if ((coord & ~(dims.xy - 1)) != ivec2(0, 0)) {\n"
 209	"		discard;\n"
 210	"	}\n"
 211	"	color = renderTile((coord.x >> 3) + (coord.y >> 3) * stride, 16 + localPalette, coord & 7);\n"
 212	"	flags = inflags / flagCoeff;\n"
 213	"}";
 214
 215static const char* const _composite =
 216	"varying vec2 texCoord;\n"
 217	"uniform int scale;\n"
 218	"uniform vec3 blend;\n"
 219	"uniform sampler2D layer;\n"
 220	"uniform sampler2D layerFlags;\n"
 221	"uniform sampler2D oldLayer;\n"
 222	"uniform sampler2D oldFlags;\n"
 223	"out vec4 color;\n"
 224	"out vec3 flags;\n"
 225	"const vec3 flagCoeff = vec3(32., 8., 4.);\n"
 226
 227	"void main() {\n"
 228	"	vec4 pix = texelFetch(layer, ivec2(texCoord * scale), 0);\n"
 229	"	if (pix.a == 0) {\n"
 230	"		discard;\n"
 231	"	}\n"
 232	"	ivec3 inflags = ivec3(texelFetch(layerFlags, ivec2(texCoord * scale), 0).xyz * flagCoeff);\n"
 233	"	ivec3 oflags = ivec3(texelFetch(oldFlags, ivec2(texCoord * scale), 0).xyz * flagCoeff);\n"
 234	"	ivec3 outflags = ivec3(0, 0, 0);\n"
 235	"	if (inflags.x < oflags.x) {\n"
 236	"		outflags = inflags;\n"
 237	"		if (inflags.z == 1 && (inflags.y & 1) == 1 && (oflags.y & 2) == 2) {\n"
 238	"			vec4 oldpix = texelFetch(oldLayer, ivec2(texCoord * scale), 0);\n"
 239	"			pix *= blend.x;\n"
 240	"			pix += oldpix * blend.y;\n"
 241	"		}\n"
 242	"	} else {\n"
 243	"		pix = texelFetch(oldLayer, ivec2(texCoord * scale), 0);\n"
 244	"		outflags = oflags;\n"
 245	"	}\n"
 246	"	color = pix;\n"
 247	"	flags = outflags / flagCoeff;\n"
 248	"}";
 249
 250static const GLint _vertices[] = {
 251	0, 0,
 252	0, 1,
 253	1, 1,
 254	1, 0,
 255};
 256
 257void GBAVideoGLRendererCreate(struct GBAVideoGLRenderer* renderer) {
 258	renderer->d.init = GBAVideoGLRendererInit;
 259	renderer->d.reset = GBAVideoGLRendererReset;
 260	renderer->d.deinit = GBAVideoGLRendererDeinit;
 261	renderer->d.writeVideoRegister = GBAVideoGLRendererWriteVideoRegister;
 262	renderer->d.writeVRAM = GBAVideoGLRendererWriteVRAM;
 263	renderer->d.writeOAM = GBAVideoGLRendererWriteOAM;
 264	renderer->d.writePalette = GBAVideoGLRendererWritePalette;
 265	renderer->d.drawScanline = GBAVideoGLRendererDrawScanline;
 266	renderer->d.finishFrame = GBAVideoGLRendererFinishFrame;
 267	renderer->d.getPixels = GBAVideoGLRendererGetPixels;
 268	renderer->d.putPixels = GBAVideoGLRendererPutPixels;
 269
 270	renderer->d.disableBG[0] = false;
 271	renderer->d.disableBG[1] = false;
 272	renderer->d.disableBG[2] = false;
 273	renderer->d.disableBG[3] = false;
 274	renderer->d.disableOBJ = false;
 275
 276	renderer->scale = 1;
 277}
 278
 279void _compileShader(struct GBAVideoGLRenderer* glRenderer, GLuint program, const char** shaderBuffer, int shaderBufferLines, GLuint vs, char* log) {
 280	GLuint fs = glCreateShader(GL_FRAGMENT_SHADER);
 281	glAttachShader(program, vs);
 282	glAttachShader(program, fs);
 283	glShaderSource(fs, shaderBufferLines, shaderBuffer, 0);
 284	glCompileShader(fs);
 285	glGetShaderInfoLog(fs, 1024, 0, log);
 286	if (log[0]) {
 287		mLOG(GBA_VIDEO, ERROR, "Fragment shader compilation failure: %s", log);
 288	}
 289	glLinkProgram(program);
 290	glGetProgramInfoLog(program, 1024, 0, log);
 291	if (log[0]) {
 292		mLOG(GBA_VIDEO, ERROR, "Program link failure: %s", log);
 293	}
 294	glDeleteShader(fs);
 295	glBindFragDataLocation(program, 0, "color");
 296	glBindFragDataLocation(program, 1, "flags");
 297}
 298
 299void GBAVideoGLRendererInit(struct GBAVideoRenderer* renderer) {
 300	struct GBAVideoGLRenderer* glRenderer = (struct GBAVideoGLRenderer*) renderer;
 301	glGenFramebuffers(2, glRenderer->fbo);
 302	glGenTextures(3, glRenderer->layers);
 303
 304	glGenTextures(1, &glRenderer->paletteTex);
 305	glBindTexture(GL_TEXTURE_2D, glRenderer->paletteTex);
 306	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
 307	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
 308
 309	glGenTextures(1, &glRenderer->vramTex);
 310	glBindTexture(GL_TEXTURE_2D, glRenderer->vramTex);
 311	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
 312	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
 313	glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA4, 256, 192, 0, GL_RGBA, GL_UNSIGNED_SHORT_4_4_4_4, 0);
 314
 315	glGenTextures(1, &glRenderer->oamTex);
 316	glBindTexture(GL_TEXTURE_2D, glRenderer->oamTex);
 317	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
 318	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
 319
 320	glBindFramebuffer(GL_FRAMEBUFFER, glRenderer->fbo[GBA_GL_FBO_OBJ]);
 321	glBindTexture(GL_TEXTURE_2D, glRenderer->layers[GBA_GL_TEX_OBJ_COLOR]);
 322	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
 323	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
 324	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
 325	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
 326	glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, GBA_VIDEO_HORIZONTAL_PIXELS * glRenderer->scale, GBA_VIDEO_VERTICAL_PIXELS * glRenderer->scale, 0, GL_RGBA, GL_UNSIGNED_BYTE, 0);
 327	glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, glRenderer->layers[GBA_GL_TEX_OBJ_COLOR], 0);
 328
 329	glBindTexture(GL_TEXTURE_2D, glRenderer->layers[GBA_GL_TEX_OBJ_FLAGS]);
 330	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
 331	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
 332	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
 333	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
 334	glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, GBA_VIDEO_HORIZONTAL_PIXELS * glRenderer->scale, GBA_VIDEO_VERTICAL_PIXELS * glRenderer->scale, 0, GL_RGB, GL_UNSIGNED_BYTE, 0);
 335	glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT1, GL_TEXTURE_2D, glRenderer->layers[GBA_GL_TEX_OBJ_FLAGS], 0);
 336
 337	glBindFramebuffer(GL_FRAMEBUFFER, glRenderer->fbo[GBA_GL_FBO_COMPOSITE]);
 338	glBindTexture(GL_TEXTURE_2D, glRenderer->outputTex);
 339	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
 340	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
 341	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
 342	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
 343	glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, GBA_VIDEO_HORIZONTAL_PIXELS * glRenderer->scale, GBA_VIDEO_VERTICAL_PIXELS * glRenderer->scale, 0, GL_RGB, GL_UNSIGNED_BYTE, 0);
 344	glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, glRenderer->outputTex, 0);
 345
 346	glBindTexture(GL_TEXTURE_2D, glRenderer->layers[GBA_GL_TEX_COMPOSITE_FLAGS]);
 347	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
 348	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
 349	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
 350	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
 351	glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, GBA_VIDEO_HORIZONTAL_PIXELS * glRenderer->scale, GBA_VIDEO_VERTICAL_PIXELS * glRenderer->scale, 0, GL_RGB, GL_UNSIGNED_BYTE, 0);
 352	glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT1, GL_TEXTURE_2D, glRenderer->layers[GBA_GL_TEX_COMPOSITE_FLAGS], 0);
 353
 354	glBindFramebuffer(GL_FRAMEBUFFER, 0);
 355
 356	int i;
 357	for (i = 0; i < 4; ++i) {
 358		glRenderer->bg[i].index = i;
 359		glGenFramebuffers(1, &glRenderer->bg[i].fbo);
 360		glGenTextures(1, &glRenderer->bg[i].tex);
 361		glGenTextures(1, &glRenderer->bg[i].flags);
 362		glBindFramebuffer(GL_FRAMEBUFFER, glRenderer->bg[i].fbo);
 363
 364		glBindTexture(GL_TEXTURE_2D, glRenderer->bg[i].tex);
 365		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
 366		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
 367		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
 368		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
 369		glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, GBA_VIDEO_HORIZONTAL_PIXELS * glRenderer->scale, GBA_VIDEO_VERTICAL_PIXELS * glRenderer->scale, 0, GL_RGBA, GL_UNSIGNED_BYTE, 0);
 370		glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, glRenderer->bg[i].tex, 0);
 371
 372		glBindTexture(GL_TEXTURE_2D, glRenderer->bg[i].flags);
 373		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
 374		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
 375		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
 376		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
 377		glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, GBA_VIDEO_HORIZONTAL_PIXELS * glRenderer->scale, GBA_VIDEO_VERTICAL_PIXELS * glRenderer->scale, 0, GL_RGB, GL_UNSIGNED_BYTE, 0);
 378		glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT1, GL_TEXTURE_2D, glRenderer->bg[i].flags, 0);
 379
 380		glBindFramebuffer(GL_FRAMEBUFFER, 0);
 381	}
 382
 383	glRenderer->compositeProgram = glCreateProgram();
 384	glRenderer->objProgram[0] = glCreateProgram();
 385	glRenderer->objProgram[1] = glCreateProgram();
 386	glRenderer->bgProgram[0] = glCreateProgram();
 387	glRenderer->bgProgram[1] = glCreateProgram();
 388	glRenderer->bgProgram[2] = glCreateProgram();
 389	glRenderer->bgProgram[3] = glCreateProgram();
 390	glRenderer->bgProgram[4] = glCreateProgram();
 391	glRenderer->bgProgram[5] = glCreateProgram();
 392
 393	char log[1024];
 394	const GLchar* shaderBuffer[8];
 395	shaderBuffer[0] = _gl3Header;
 396
 397	GLuint vs = glCreateShader(GL_VERTEX_SHADER);
 398	shaderBuffer[1] = _vertexShader;
 399	glShaderSource(vs, 2, shaderBuffer, 0);
 400	glCompileShader(vs);
 401	glGetShaderInfoLog(vs, 1024, 0, log);
 402	if (log[0]) {
 403		mLOG(GBA_VIDEO, ERROR, "Vertex shader compilation failure: %s", log);
 404	}
 405
 406	shaderBuffer[1] = _renderMode0;
 407
 408	shaderBuffer[2] = _renderTile16;
 409	_compileShader(glRenderer, glRenderer->bgProgram[0], shaderBuffer, 3, vs, log);
 410
 411	shaderBuffer[2] = _renderTile256;
 412	_compileShader(glRenderer, glRenderer->bgProgram[1], shaderBuffer, 3, vs, log);
 413
 414	shaderBuffer[1] = _renderMode2;
 415
 416	shaderBuffer[2] = _fetchTileOverflow;
 417	_compileShader(glRenderer, glRenderer->bgProgram[2], shaderBuffer, 3, vs, log);
 418
 419	shaderBuffer[2] = _fetchTileNoOverflow;
 420	_compileShader(glRenderer, glRenderer->bgProgram[3], shaderBuffer, 3, vs, log);
 421
 422	shaderBuffer[1] = _renderObj;
 423
 424	shaderBuffer[2] = _renderTile16;
 425	_compileShader(glRenderer, glRenderer->objProgram[0], shaderBuffer, 3, vs, log);
 426
 427	shaderBuffer[2] = _renderTile256;
 428	_compileShader(glRenderer, glRenderer->objProgram[1], shaderBuffer, 3, vs, log);
 429
 430	shaderBuffer[1] = _composite;
 431	_compileShader(glRenderer, glRenderer->compositeProgram, shaderBuffer, 2, vs, log);
 432
 433	glDeleteShader(vs);
 434
 435	GBAVideoGLRendererReset(renderer);
 436}
 437
 438void GBAVideoGLRendererDeinit(struct GBAVideoRenderer* renderer) {
 439	struct GBAVideoGLRenderer* glRenderer = (struct GBAVideoGLRenderer*) renderer;
 440	glDeleteFramebuffers(2, glRenderer->fbo);
 441	glDeleteTextures(3, glRenderer->layers);
 442	glDeleteTextures(1, &glRenderer->paletteTex);
 443	glDeleteTextures(1, &glRenderer->vramTex);
 444	glDeleteTextures(1, &glRenderer->oamTex);
 445
 446	glDeleteProgram(glRenderer->bgProgram[0]);
 447	glDeleteProgram(glRenderer->bgProgram[1]);
 448	glDeleteProgram(glRenderer->bgProgram[2]);
 449	glDeleteProgram(glRenderer->bgProgram[3]);
 450	glDeleteProgram(glRenderer->bgProgram[4]);
 451	glDeleteProgram(glRenderer->bgProgram[5]);
 452	glDeleteProgram(glRenderer->bgProgram[6]);
 453	glDeleteProgram(glRenderer->objProgram[0]);
 454	glDeleteProgram(glRenderer->objProgram[1]);
 455	glDeleteProgram(glRenderer->compositeProgram);
 456}
 457
 458void GBAVideoGLRendererReset(struct GBAVideoRenderer* renderer) {
 459	struct GBAVideoGLRenderer* glRenderer = (struct GBAVideoGLRenderer*) renderer;
 460
 461	glRenderer->paletteDirty = true;
 462	glRenderer->vramDirty = 0xFFFFFF;
 463	glRenderer->firstAffine = -1;
 464}
 465
 466void GBAVideoGLRendererWriteVRAM(struct GBAVideoRenderer* renderer, uint32_t address) {
 467	struct GBAVideoGLRenderer* glRenderer = (struct GBAVideoGLRenderer*) renderer;
 468	glRenderer->vramDirty |= 1 << (address >> 12);
 469}
 470
 471void GBAVideoGLRendererWriteOAM(struct GBAVideoRenderer* renderer, uint32_t oam) {
 472	UNUSED(oam);
 473	struct GBAVideoGLRenderer* glRenderer = (struct GBAVideoGLRenderer*) renderer;
 474	glRenderer->oamDirty = true;
 475}
 476
 477void GBAVideoGLRendererWritePalette(struct GBAVideoRenderer* renderer, uint32_t address, uint16_t value) {
 478	UNUSED(address);
 479	UNUSED(value);
 480	struct GBAVideoGLRenderer* glRenderer = (struct GBAVideoGLRenderer*) renderer;
 481	glRenderer->paletteDirty = true;
 482}
 483
 484uint16_t GBAVideoGLRendererWriteVideoRegister(struct GBAVideoRenderer* renderer, uint32_t address, uint16_t value) {
 485	struct GBAVideoGLRenderer* glRenderer = (struct GBAVideoGLRenderer*) renderer;
 486	if (renderer->cache) {
 487		GBAVideoCacheWriteVideoRegister(renderer->cache, address, value);
 488	}
 489
 490	switch (address) {
 491	case REG_DISPCNT:
 492		value &= 0xFFF7;
 493		glRenderer->dispcnt = value;
 494		GBAVideoGLRendererUpdateDISPCNT(glRenderer);
 495		break;
 496	case REG_BG0CNT:
 497		value &= 0xDFFF;
 498		GBAVideoGLRendererWriteBGCNT(&glRenderer->bg[0], value);
 499		break;
 500	case REG_BG1CNT:
 501		value &= 0xDFFF;
 502		GBAVideoGLRendererWriteBGCNT(&glRenderer->bg[1], value);
 503		break;
 504	case REG_BG2CNT:
 505		value &= 0xFFFF;
 506		GBAVideoGLRendererWriteBGCNT(&glRenderer->bg[2], value);
 507		break;
 508	case REG_BG3CNT:
 509		value &= 0xFFFF;
 510		GBAVideoGLRendererWriteBGCNT(&glRenderer->bg[3], value);
 511		break;
 512	case REG_BG0HOFS:
 513		value &= 0x01FF;
 514		glRenderer->bg[0].x = value;
 515		break;
 516	case REG_BG0VOFS:
 517		value &= 0x01FF;
 518		glRenderer->bg[0].y = value;
 519		break;
 520	case REG_BG1HOFS:
 521		value &= 0x01FF;
 522		glRenderer->bg[1].x = value;
 523		break;
 524	case REG_BG1VOFS:
 525		value &= 0x01FF;
 526		glRenderer->bg[1].y = value;
 527		break;
 528	case REG_BG2HOFS:
 529		value &= 0x01FF;
 530		glRenderer->bg[2].x = value;
 531		break;
 532	case REG_BG2VOFS:
 533		value &= 0x01FF;
 534		glRenderer->bg[2].y = value;
 535		break;
 536	case REG_BG3HOFS:
 537		value &= 0x01FF;
 538		glRenderer->bg[3].x = value;
 539		break;
 540	case REG_BG3VOFS:
 541		value &= 0x01FF;
 542		glRenderer->bg[3].y = value;
 543		break;
 544	case REG_BG2PA:
 545		glRenderer->bg[2].affine[0].dx = value;
 546		break;
 547	case REG_BG2PB:
 548		glRenderer->bg[2].affine[0].dmx = value;
 549		break;
 550	case REG_BG2PC:
 551		glRenderer->bg[2].affine[0].dy = value;
 552		break;
 553	case REG_BG2PD:
 554		glRenderer->bg[2].affine[0].dmy = value;
 555		break;
 556	case REG_BG2X_LO:
 557		GBAVideoGLRendererWriteBGX_LO(&glRenderer->bg[2], value);
 558		break;
 559	case REG_BG2X_HI:
 560		GBAVideoGLRendererWriteBGX_HI(&glRenderer->bg[2], value);
 561		break;
 562	case REG_BG2Y_LO:
 563		GBAVideoGLRendererWriteBGY_LO(&glRenderer->bg[2], value);
 564		break;
 565	case REG_BG2Y_HI:
 566		GBAVideoGLRendererWriteBGY_HI(&glRenderer->bg[2], value);
 567		break;
 568	case REG_BG3PA:
 569		glRenderer->bg[3].affine[0].dx = value;
 570		break;
 571	case REG_BG3PB:
 572		glRenderer->bg[3].affine[0].dmx = value;
 573		break;
 574	case REG_BG3PC:
 575		glRenderer->bg[3].affine[0].dy = value;
 576		break;
 577	case REG_BG3PD:
 578		glRenderer->bg[3].affine[0].dmy = value;
 579		break;
 580	case REG_BG3X_LO:
 581		GBAVideoGLRendererWriteBGX_LO(&glRenderer->bg[3], value);
 582		break;
 583	case REG_BG3X_HI:
 584		GBAVideoGLRendererWriteBGX_HI(&glRenderer->bg[3], value);
 585		break;
 586	case REG_BG3Y_LO:
 587		GBAVideoGLRendererWriteBGY_LO(&glRenderer->bg[3], value);
 588		break;
 589	case REG_BG3Y_HI:
 590		GBAVideoGLRendererWriteBGY_HI(&glRenderer->bg[3], value);
 591		break;
 592	case REG_BLDCNT:
 593		GBAVideoGLRendererWriteBLDCNT(glRenderer, value);
 594		value &= 0x3FFF;
 595		break;
 596	case REG_BLDALPHA:
 597		glRenderer->blda = value & 0x1F;
 598		if (glRenderer->blda > 0x10) {
 599			glRenderer->blda = 0x10;
 600		}
 601		glRenderer->bldb = (value >> 8) & 0x1F;
 602		if (glRenderer->bldb > 0x10) {
 603			glRenderer->bldb = 0x10;
 604		}
 605		value &= 0x1F1F;
 606		break;
 607	case REG_BLDY:
 608		value &= 0x1F;
 609		if (value > 0x10) {
 610			value = 0x10;
 611		}
 612		if (glRenderer->bldy != value) {
 613			glRenderer->bldy = value;
 614		}
 615		break;
 616	case REG_WIN0H:
 617		/*glRenderer->winN[0].h.end = value;
 618		glRenderer->winN[0].h.start = value >> 8;
 619		if (glRenderer->winN[0].h.start > GBA_VIDEO_HORIZONTAL_PIXELS && glRenderer->winN[0].h.start > glRenderer->winN[0].h.end) {
 620			glRenderer->winN[0].h.start = 0;
 621		}
 622		if (glRenderer->winN[0].h.end > GBA_VIDEO_HORIZONTAL_PIXELS) {
 623			glRenderer->winN[0].h.end = GBA_VIDEO_HORIZONTAL_PIXELS;
 624			if (glRenderer->winN[0].h.start > GBA_VIDEO_HORIZONTAL_PIXELS) {
 625				glRenderer->winN[0].h.start = GBA_VIDEO_HORIZONTAL_PIXELS;
 626			}
 627		}*/
 628		break;
 629	case REG_WIN1H:
 630		/*glRenderer->winN[1].h.end = value;
 631		glRenderer->winN[1].h.start = value >> 8;
 632		if (glRenderer->winN[1].h.start > GBA_VIDEO_HORIZONTAL_PIXELS && glRenderer->winN[1].h.start > glRenderer->winN[1].h.end) {
 633			glRenderer->winN[1].h.start = 0;
 634		}
 635		if (glRenderer->winN[1].h.end > GBA_VIDEO_HORIZONTAL_PIXELS) {
 636			glRenderer->winN[1].h.end = GBA_VIDEO_HORIZONTAL_PIXELS;
 637			if (glRenderer->winN[1].h.start > GBA_VIDEO_HORIZONTAL_PIXELS) {
 638				glRenderer->winN[1].h.start = GBA_VIDEO_HORIZONTAL_PIXELS;
 639			}
 640		}*/
 641		break;
 642	case REG_WIN0V:
 643		/*glRenderer->winN[0].v.end = value;
 644		glRenderer->winN[0].v.start = value >> 8;
 645		if (glRenderer->winN[0].v.start > GBA_VIDEO_VERTICAL_PIXELS && glRenderer->winN[0].v.start > glRenderer->winN[0].v.end) {
 646			glRenderer->winN[0].v.start = 0;
 647		}
 648		if (glRenderer->winN[0].v.end > GBA_VIDEO_VERTICAL_PIXELS) {
 649			glRenderer->winN[0].v.end = GBA_VIDEO_VERTICAL_PIXELS;
 650			if (glRenderer->winN[0].v.start > GBA_VIDEO_VERTICAL_PIXELS) {
 651				glRenderer->winN[0].v.start = GBA_VIDEO_VERTICAL_PIXELS;
 652			}
 653		}*/
 654		break;
 655	case REG_WIN1V:
 656		/*glRenderer->winN[1].v.end = value;
 657		glRenderer->winN[1].v.start = value >> 8;
 658		if (glRenderer->winN[1].v.start > GBA_VIDEO_VERTICAL_PIXELS && glRenderer->winN[1].v.start > glRenderer->winN[1].v.end) {
 659			glRenderer->winN[1].v.start = 0;
 660		}
 661		if (glRenderer->winN[1].v.end > GBA_VIDEO_VERTICAL_PIXELS) {
 662			glRenderer->winN[1].v.end = GBA_VIDEO_VERTICAL_PIXELS;
 663			if (glRenderer->winN[1].v.start > GBA_VIDEO_VERTICAL_PIXELS) {
 664				glRenderer->winN[1].v.start = GBA_VIDEO_VERTICAL_PIXELS;
 665			}
 666		}*/
 667		break;
 668	case REG_WININ:
 669		value &= 0x3F3F;
 670		//glRenderer->winN[0].control.packed = value;
 671		//glRenderer->winN[1].control.packed = value >> 8;
 672		break;
 673	case REG_WINOUT:
 674		value &= 0x3F3F;
 675		//glRenderer->winout.packed = value;
 676		//glRenderer->objwin.packed = value >> 8;
 677		break;
 678	case REG_MOSAIC:
 679		glRenderer->mosaic = value;
 680		break;
 681	case REG_GREENSWP:
 682		mLOG(GBA_VIDEO, STUB, "Stub video register write: 0x%03X", address);
 683		break;
 684	default:
 685		mLOG(GBA_VIDEO, GAME_ERROR, "Invalid video register: 0x%03X", address);
 686	}
 687	return value;
 688}
 689
 690void GBAVideoGLRendererDrawScanline(struct GBAVideoRenderer* renderer, int y) {
 691	struct GBAVideoGLRenderer* glRenderer = (struct GBAVideoGLRenderer*) renderer;
 692	if (glRenderer->paletteDirty) {
 693		glBindTexture(GL_TEXTURE_2D, glRenderer->paletteTex);
 694		glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB5_A1, 16, 32, 0, GL_RGBA, GL_UNSIGNED_SHORT_1_5_5_5_REV, glRenderer->d.palette);
 695		glRenderer->paletteDirty = false;
 696	}
 697	int i;
 698	for (i = 0; i < 24; ++i) {
 699		if (!(glRenderer->vramDirty & (1 << i))) {
 700			continue;
 701		}
 702		// TODO: PBOs
 703		glBindTexture(GL_TEXTURE_2D, glRenderer->vramTex);
 704		glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 8 * i, 256, 8, GL_RGBA, GL_UNSIGNED_SHORT_4_4_4_4, &glRenderer->d.vram[2048 * i]);
 705	}
 706	glRenderer->vramDirty = 0;
 707
 708	uint32_t backdrop = M_RGB5_TO_RGB8(renderer->palette[0]);
 709	glClearColor(((backdrop >> 16) & 0xFF) / 256., ((backdrop >> 8) & 0xFF) / 256., (backdrop & 0xFF) / 256., 0.f);
 710	glBindFramebuffer(GL_FRAMEBUFFER, glRenderer->fbo[GBA_GL_FBO_COMPOSITE]);
 711	glEnable(GL_SCISSOR_TEST);
 712	glScissor(0, y * glRenderer->scale, GBA_VIDEO_HORIZONTAL_PIXELS * glRenderer->scale, glRenderer->scale);
 713	glDrawBuffer(GL_COLOR_ATTACHMENT0);
 714	glClear(GL_COLOR_BUFFER_BIT);
 715	if (y == 0) {
 716		glDisable(GL_SCISSOR_TEST);
 717		glDrawBuffer(GL_COLOR_ATTACHMENT1);
 718		glClearColor(1, (glRenderer->target1Bd | (glRenderer->target2Bd * 2)) / 8.f, 0, 1);
 719		glClear(GL_COLOR_BUFFER_BIT);
 720		
 721		glClearColor(0, 0, 0, 0);
 722		glBindFramebuffer(GL_FRAMEBUFFER, glRenderer->fbo[GBA_GL_FBO_OBJ]);
 723		glDrawBuffer(GL_COLOR_ATTACHMENT0);
 724		glClear(GL_COLOR_BUFFER_BIT);
 725		glDrawBuffer(GL_COLOR_ATTACHMENT1);
 726		glClear(GL_COLOR_BUFFER_BIT);
 727
 728		for (i = 0; i < 4; ++i) {
 729			glBindFramebuffer(GL_FRAMEBUFFER, glRenderer->bg[i].fbo);
 730			glDrawBuffer(GL_COLOR_ATTACHMENT0);
 731			glClear(GL_COLOR_BUFFER_BIT);
 732			glDrawBuffer(GL_COLOR_ATTACHMENT1);
 733			glClear(GL_COLOR_BUFFER_BIT);
 734		}
 735		glDrawBuffer(GL_COLOR_ATTACHMENT0);
 736		glEnable(GL_SCISSOR_TEST);
 737	}
 738	glBindFramebuffer(GL_FRAMEBUFFER, 0);
 739
 740	if (GBARegisterDISPCNTGetMode(glRenderer->dispcnt) != 0) {
 741		if (glRenderer->firstAffine < 0) {
 742			memcpy(&glRenderer->bg[2].affine[3], &glRenderer->bg[2].affine[0], sizeof(struct GBAVideoGLAffine));
 743			memcpy(&glRenderer->bg[3].affine[3], &glRenderer->bg[3].affine[0], sizeof(struct GBAVideoGLAffine));
 744			memcpy(&glRenderer->bg[2].affine[2], &glRenderer->bg[2].affine[0], sizeof(struct GBAVideoGLAffine));
 745			memcpy(&glRenderer->bg[3].affine[2], &glRenderer->bg[3].affine[0], sizeof(struct GBAVideoGLAffine));
 746			memcpy(&glRenderer->bg[2].affine[1], &glRenderer->bg[2].affine[0], sizeof(struct GBAVideoGLAffine));
 747			memcpy(&glRenderer->bg[3].affine[1], &glRenderer->bg[3].affine[0], sizeof(struct GBAVideoGLAffine));
 748			glRenderer->firstAffine = y;
 749		} else if (y - glRenderer->firstAffine == 1) {
 750			memcpy(&glRenderer->bg[2].affine[1], &glRenderer->bg[2].affine[0], sizeof(struct GBAVideoGLAffine));
 751			memcpy(&glRenderer->bg[3].affine[1], &glRenderer->bg[3].affine[0], sizeof(struct GBAVideoGLAffine));			
 752		}
 753	} else {
 754		glRenderer->firstAffine = -1;
 755	}
 756
 757	int spriteLayers = 0;
 758	if (GBARegisterDISPCNTIsObjEnable(glRenderer->dispcnt) && !glRenderer->d.disableOBJ) {
 759		if (glRenderer->oamDirty) {
 760			glBindTexture(GL_TEXTURE_2D, glRenderer->oamTex);
 761			glTexImage2D(GL_TEXTURE_2D, 0, GL_R16UI, 4, 128, 0, GL_RED_INTEGER, GL_UNSIGNED_SHORT, glRenderer->d.oam);
 762			glRenderer->oamMax = GBAVideoRendererCleanOAM(glRenderer->d.oam->obj, glRenderer->sprites, 0);
 763			glRenderer->oamDirty = false;
 764		}
 765		int i;
 766		for (i = glRenderer->oamMax; i--;) {
 767			struct GBAVideoRendererSprite* sprite = &glRenderer->sprites[i];
 768			if ((y < sprite->y && (sprite->endY - 256 < 0 || y >= sprite->endY - 256)) || y >= sprite->endY) {
 769				continue;
 770			}
 771
 772			GBAVideoGLRendererDrawSprite(glRenderer, &sprite->obj, y, sprite->y);
 773			spriteLayers |= 1 << GBAObjAttributesCGetPriority(sprite->obj.c);
 774		}
 775	}
 776
 777	_compositeLayer(glRenderer, glRenderer->layers[GBA_GL_TEX_OBJ_COLOR], glRenderer->layers[GBA_GL_TEX_OBJ_FLAGS], y);
 778	unsigned priority;
 779	for (priority = 4; priority--;) {
 780		if (TEST_LAYER_ENABLED(0) && GBARegisterDISPCNTGetMode(glRenderer->dispcnt) < 2) {
 781			GBAVideoGLRendererDrawBackgroundMode0(glRenderer, &glRenderer->bg[0], y);
 782		}
 783		if (TEST_LAYER_ENABLED(1) && GBARegisterDISPCNTGetMode(glRenderer->dispcnt) < 2) {
 784			GBAVideoGLRendererDrawBackgroundMode0(glRenderer, &glRenderer->bg[1], y);
 785		}
 786		if (TEST_LAYER_ENABLED(2)) {
 787			switch (GBARegisterDISPCNTGetMode(glRenderer->dispcnt)) {
 788			case 0:
 789				GBAVideoGLRendererDrawBackgroundMode0(glRenderer, &glRenderer->bg[2], y);
 790				break;
 791			case 1:
 792			case 2:
 793				GBAVideoGLRendererDrawBackgroundMode2(glRenderer, &glRenderer->bg[2], y);
 794				break;
 795			case 3:
 796				//GBAVideoGLRendererDrawBackgroundMode3(glRenderer, &glRenderer->bg[2], y);
 797				break;
 798			case 4:
 799				//GBAVideoGLRendererDrawBackgroundMode4(glRenderer, &glRenderer->bg[2], y);
 800				break;
 801			case 5:
 802				//GBAVideoGLRendererDrawBackgroundMode5(glRenderer, &glRenderer->bg[2], y);
 803				break;
 804			}
 805		}
 806		if (TEST_LAYER_ENABLED(3)) {
 807			switch (GBARegisterDISPCNTGetMode(glRenderer->dispcnt)) {
 808			case 0:
 809				GBAVideoGLRendererDrawBackgroundMode0(glRenderer, &glRenderer->bg[3], y);
 810				break;
 811			case 2:
 812				GBAVideoGLRendererDrawBackgroundMode2(glRenderer, &glRenderer->bg[3], y);
 813				break;
 814			}
 815		}
 816	}
 817
 818	if (GBARegisterDISPCNTGetMode(glRenderer->dispcnt) != 0) {
 819		memcpy(&glRenderer->bg[2].affine[3], &glRenderer->bg[2].affine[2], sizeof(struct GBAVideoGLAffine));
 820		memcpy(&glRenderer->bg[3].affine[3], &glRenderer->bg[3].affine[2], sizeof(struct GBAVideoGLAffine));
 821		memcpy(&glRenderer->bg[2].affine[2], &glRenderer->bg[2].affine[1], sizeof(struct GBAVideoGLAffine));
 822		memcpy(&glRenderer->bg[3].affine[2], &glRenderer->bg[3].affine[1], sizeof(struct GBAVideoGLAffine));
 823		memcpy(&glRenderer->bg[2].affine[1], &glRenderer->bg[2].affine[0], sizeof(struct GBAVideoGLAffine));
 824		memcpy(&glRenderer->bg[3].affine[1], &glRenderer->bg[3].affine[0], sizeof(struct GBAVideoGLAffine));
 825
 826		glRenderer->bg[2].affine[0].sx += glRenderer->bg[2].affine[0].dmx;
 827		glRenderer->bg[2].affine[0].sy += glRenderer->bg[2].affine[0].dmy;
 828		glRenderer->bg[3].affine[0].sx += glRenderer->bg[3].affine[0].dmx;
 829		glRenderer->bg[3].affine[0].sy += glRenderer->bg[3].affine[0].dmy;
 830	}
 831}
 832
 833void GBAVideoGLRendererFinishFrame(struct GBAVideoRenderer* renderer) {
 834	struct GBAVideoGLRenderer* glRenderer = (struct GBAVideoGLRenderer*) renderer;
 835	glRenderer->firstAffine = -1;
 836	glRenderer->bg[2].affine[0].sx = glRenderer->bg[2].refx;
 837	glRenderer->bg[2].affine[0].sy = glRenderer->bg[2].refy;
 838	glRenderer->bg[3].affine[0].sx = glRenderer->bg[3].refx;
 839	glRenderer->bg[3].affine[0].sy = glRenderer->bg[3].refy;
 840	glFlush();
 841}
 842
 843void GBAVideoGLRendererGetPixels(struct GBAVideoRenderer* renderer, size_t* stride, const void** pixels) {
 844
 845}
 846
 847void GBAVideoGLRendererPutPixels(struct GBAVideoRenderer* renderer, size_t stride, const void* pixels) {
 848
 849}
 850
 851static void _enableBg(struct GBAVideoGLRenderer* renderer, int bg, bool active) {
 852	int wasActive = renderer->bg[bg].enabled;
 853	if (!active) {
 854		renderer->bg[bg].enabled = 0;
 855	} else if (!wasActive && active) {
 856		/*if (renderer->nextY == 0 || GBARegisterDISPCNTGetMode(renderer->dispcnt) > 2) {
 857			// TODO: Investigate in more depth how switching background works in different modes
 858			renderer->bg[bg].enabled = 4;
 859		} else {
 860			renderer->bg[bg].enabled = 1;
 861		}*/
 862		renderer->bg[bg].enabled = 4;
 863	}
 864}
 865
 866static void GBAVideoGLRendererUpdateDISPCNT(struct GBAVideoGLRenderer* renderer) {
 867	_enableBg(renderer, 0, GBARegisterDISPCNTGetBg0Enable(renderer->dispcnt));
 868	_enableBg(renderer, 1, GBARegisterDISPCNTGetBg1Enable(renderer->dispcnt));
 869	_enableBg(renderer, 2, GBARegisterDISPCNTGetBg2Enable(renderer->dispcnt));
 870	_enableBg(renderer, 3, GBARegisterDISPCNTGetBg3Enable(renderer->dispcnt));
 871}
 872
 873static void GBAVideoGLRendererWriteBGCNT(struct GBAVideoGLBackground* bg, uint16_t value) {
 874	bg->priority = GBARegisterBGCNTGetPriority(value);
 875	bg->charBase = GBARegisterBGCNTGetCharBase(value) << 13;
 876	bg->mosaic = GBARegisterBGCNTGetMosaic(value);
 877	bg->multipalette = GBARegisterBGCNTGet256Color(value);
 878	bg->screenBase = GBARegisterBGCNTGetScreenBase(value) << 10;
 879	bg->overflow = GBARegisterBGCNTGetOverflow(value);
 880	bg->size = GBARegisterBGCNTGetSize(value);
 881}
 882
 883static void GBAVideoGLRendererWriteBGX_LO(struct GBAVideoGLBackground* bg, uint16_t value) {
 884	bg->refx = (bg->refx & 0xFFFF0000) | value;
 885	bg->affine[0].sx = bg->refx;
 886}
 887
 888static void GBAVideoGLRendererWriteBGX_HI(struct GBAVideoGLBackground* bg, uint16_t value) {
 889	bg->refx = (bg->refx & 0x0000FFFF) | (value << 16);
 890	bg->refx <<= 4;
 891	bg->refx >>= 4;
 892	bg->affine[0].sx = bg->refx;
 893}
 894
 895static void GBAVideoGLRendererWriteBGY_LO(struct GBAVideoGLBackground* bg, uint16_t value) {
 896	bg->refy = (bg->refy & 0xFFFF0000) | value;
 897	bg->affine[0].sy = bg->refy;
 898}
 899
 900static void GBAVideoGLRendererWriteBGY_HI(struct GBAVideoGLBackground* bg, uint16_t value) {
 901	bg->refy = (bg->refy & 0x0000FFFF) | (value << 16);
 902	bg->refy <<= 4;
 903	bg->refy >>= 4;
 904	bg->affine[0].sy = bg->refy;
 905}
 906
 907static void GBAVideoGLRendererWriteBLDCNT(struct GBAVideoGLRenderer* renderer, uint16_t value) {
 908	renderer->bg[0].target1 = GBARegisterBLDCNTGetTarget1Bg0(value);
 909	renderer->bg[1].target1 = GBARegisterBLDCNTGetTarget1Bg1(value);
 910	renderer->bg[2].target1 = GBARegisterBLDCNTGetTarget1Bg2(value);
 911	renderer->bg[3].target1 = GBARegisterBLDCNTGetTarget1Bg3(value);
 912	renderer->bg[0].target2 = GBARegisterBLDCNTGetTarget2Bg0(value);
 913	renderer->bg[1].target2 = GBARegisterBLDCNTGetTarget2Bg1(value);
 914	renderer->bg[2].target2 = GBARegisterBLDCNTGetTarget2Bg2(value);
 915	renderer->bg[3].target2 = GBARegisterBLDCNTGetTarget2Bg3(value);
 916
 917	renderer->blendEffect = GBARegisterBLDCNTGetEffect(value);
 918	renderer->target1Obj = GBARegisterBLDCNTGetTarget1Obj(value);
 919	renderer->target1Bd = GBARegisterBLDCNTGetTarget1Bd(value);
 920	renderer->target2Obj = GBARegisterBLDCNTGetTarget2Obj(value);
 921	renderer->target2Bd = GBARegisterBLDCNTGetTarget2Bd(value);
 922}
 923
 924static void _compositeLayer(struct GBAVideoGLRenderer* renderer, GLuint tex, GLuint flags, int y) {
 925	if ((y & 0x1F) != 0x1F) {
 926		return;
 927	}
 928	glBindFramebuffer(GL_FRAMEBUFFER, renderer->fbo[GBA_GL_FBO_COMPOSITE]);
 929	glViewport(0, 0, GBA_VIDEO_HORIZONTAL_PIXELS * renderer->scale, GBA_VIDEO_VERTICAL_PIXELS * renderer->scale);
 930	glScissor(0, (y & ~0x1F) * renderer->scale, GBA_VIDEO_HORIZONTAL_PIXELS * renderer->scale, 0x20 * renderer->scale);
 931	glUseProgram(renderer->compositeProgram);
 932	glActiveTexture(GL_TEXTURE0);
 933	glBindTexture(GL_TEXTURE_2D, tex);
 934	glActiveTexture(GL_TEXTURE0 + 1);
 935	glBindTexture(GL_TEXTURE_2D, flags);
 936	glActiveTexture(GL_TEXTURE0 + 2);
 937	glBindTexture(GL_TEXTURE_2D, renderer->outputTex);
 938	glActiveTexture(GL_TEXTURE0 + 3);
 939	glBindTexture(GL_TEXTURE_2D, renderer->layers[GBA_GL_TEX_COMPOSITE_FLAGS]);
 940	glUniform2i(0, 0x20, y & ~0x1F);
 941	glUniform2i(1, GBA_VIDEO_HORIZONTAL_PIXELS, GBA_VIDEO_VERTICAL_PIXELS);
 942	glUniform1i(2, renderer->scale);
 943	glUniform3f(3, renderer->blda / 16.f, renderer->bldb / 16.f, renderer->bldy / 16.f);
 944	glUniform1i(4, 0);
 945	glUniform1i(5, 1);
 946	glUniform1i(6, 2);
 947	glUniform1i(7, 3);
 948	glVertexAttribPointer(0, 2, GL_INT, GL_FALSE, 0, _vertices);
 949	glEnableVertexAttribArray(0);
 950	glDrawBuffers(2, (GLenum[]) { GL_COLOR_ATTACHMENT0, GL_COLOR_ATTACHMENT1 });
 951	glDrawArrays(GL_TRIANGLE_FAN, 0, 4);
 952	glDrawBuffers(1, (GLenum[]) { GL_COLOR_ATTACHMENT0 });
 953	glBindFramebuffer(GL_FRAMEBUFFER, 0);
 954}
 955
 956void GBAVideoGLRendererDrawSprite(struct GBAVideoGLRenderer* renderer, struct GBAObj* sprite, int y, int spriteY) {
 957	int width = GBAVideoObjSizes[GBAObjAttributesAGetShape(sprite->a) * 4 + GBAObjAttributesBGetSize(sprite->b)][0];
 958	int height = GBAVideoObjSizes[GBAObjAttributesAGetShape(sprite->a) * 4 + GBAObjAttributesBGetSize(sprite->b)][1];
 959	int32_t x = (uint32_t) GBAObjAttributesBGetX(sprite->b) << 23;
 960	x >>= 23;
 961
 962	int align = GBAObjAttributesAIs256Color(sprite->a) && !GBARegisterDISPCNTIsObjCharacterMapping(renderer->dispcnt);
 963	unsigned charBase = (BASE_TILE >> 1) + (GBAObjAttributesCGetTile(sprite->c) & ~align) * 0x10;
 964	int stride = GBARegisterDISPCNTIsObjCharacterMapping(renderer->dispcnt) ? (width >> 3) : (0x40 >> !GBAObjAttributesAIs256Color(sprite->a));
 965
 966	if (spriteY + height >= 256) {
 967		spriteY -= 256;
 968	}
 969
 970	if (!GBAObjAttributesAIsTransformed(sprite->a) && GBAObjAttributesBIsVFlip(sprite->b)) {
 971		spriteY = (y - height) + (y - spriteY) + 1;
 972	}
 973
 974	int totalWidth = width;
 975	int totalHeight = height;
 976	if (GBAObjAttributesAIsTransformed(sprite->a) && GBAObjAttributesAIsDoubleSize(sprite->a)) {
 977		totalWidth <<= 1;
 978		totalHeight <<= 1;
 979	}
 980
 981	glBindFramebuffer(GL_FRAMEBUFFER, renderer->fbo[GBA_GL_FBO_OBJ]);
 982	glViewport(x * renderer->scale, spriteY * renderer->scale, totalWidth * renderer->scale, totalHeight * renderer->scale);
 983	glScissor(x * renderer->scale, y * renderer->scale, totalWidth * renderer->scale, renderer->scale);
 984	glUseProgram(renderer->objProgram[GBAObjAttributesAGet256Color(sprite->a)]);
 985	glActiveTexture(GL_TEXTURE0);
 986	glBindTexture(GL_TEXTURE_2D, renderer->vramTex);
 987	glActiveTexture(GL_TEXTURE0 + 1);
 988	glBindTexture(GL_TEXTURE_2D, renderer->paletteTex);
 989	glUniform2i(0, 1, y - spriteY);
 990	glUniform2i(1, (GBAObjAttributesBIsHFlip(sprite->b) && !GBAObjAttributesAIsTransformed(sprite->a)) ? -totalWidth : totalWidth, totalHeight);
 991	glUniform1i(2, 0);
 992	glUniform1i(3, 1);
 993	glUniform1i(4, charBase);
 994	glUniform1i(5, stride);
 995	glUniform1i(6, GBAObjAttributesCGetPalette(sprite->c));
 996	glUniform3i(7, GBAObjAttributesCGetPriority(sprite->c) << 3, renderer->target1Obj | (renderer->target2Obj * 2), 0);
 997	if (GBAObjAttributesAIsTransformed(sprite->a)) {
 998		struct GBAOAMMatrix mat;
 999		LOAD_16(mat.a, 0, &renderer->d.oam->mat[GBAObjAttributesBGetMatIndex(sprite->b)].a);
1000		LOAD_16(mat.b, 0, &renderer->d.oam->mat[GBAObjAttributesBGetMatIndex(sprite->b)].b);
1001		LOAD_16(mat.c, 0, &renderer->d.oam->mat[GBAObjAttributesBGetMatIndex(sprite->b)].c);
1002		LOAD_16(mat.d, 0, &renderer->d.oam->mat[GBAObjAttributesBGetMatIndex(sprite->b)].d);
1003
1004		glUniformMatrix2fv(8, 1, GL_FALSE, (GLfloat[]) { mat.a / 256.f, mat.c / 256.f, mat.b / 256.f, mat.d / 256.f });
1005	} else {
1006		glUniformMatrix2fv(8, 1, GL_FALSE, (GLfloat[]) { 1.f, 0, 0, 1.f });		
1007	}
1008	glUniform4i(9, width, height, totalWidth, totalHeight);
1009	glVertexAttribPointer(0, 2, GL_INT, GL_FALSE, 0, _vertices);
1010	glEnableVertexAttribArray(0);
1011	glDrawBuffers(2, (GLenum[]) { GL_COLOR_ATTACHMENT0, GL_COLOR_ATTACHMENT1 });
1012	glDrawArrays(GL_TRIANGLE_FAN, 0, 4);
1013	glDrawBuffers(1, (GLenum[]) { GL_COLOR_ATTACHMENT0 });
1014}
1015
1016void GBAVideoGLRendererDrawBackgroundMode0(struct GBAVideoGLRenderer* renderer, struct GBAVideoGLBackground* background, int y) {
1017	int inY = y + background->y;
1018	int yBase = inY & 0xFF;
1019	if (background->size == 2) {
1020		yBase += inY & 0x100;
1021	} else if (background->size == 3) {
1022		yBase += (inY & 0x100) << 1;
1023	}
1024	glBindFramebuffer(GL_FRAMEBUFFER, background->fbo);
1025	glViewport(0, 0, GBA_VIDEO_HORIZONTAL_PIXELS * renderer->scale, GBA_VIDEO_VERTICAL_PIXELS * renderer->scale);
1026	glScissor(0, y * renderer->scale, GBA_VIDEO_HORIZONTAL_PIXELS * renderer->scale, renderer->scale);
1027	glUseProgram(renderer->bgProgram[background->multipalette ? 1 : 0]);
1028	glActiveTexture(GL_TEXTURE0);
1029	glBindTexture(GL_TEXTURE_2D, renderer->vramTex);
1030	glActiveTexture(GL_TEXTURE0 + 1);
1031	glBindTexture(GL_TEXTURE_2D, renderer->paletteTex);
1032	glUniform2i(0, 1, y);
1033	glUniform2i(1, GBA_VIDEO_HORIZONTAL_PIXELS, GBA_VIDEO_VERTICAL_PIXELS);
1034	glUniform1i(2, 0);
1035	glUniform1i(3, 1);
1036	glUniform1i(4, background->screenBase);
1037	glUniform1i(5, background->charBase);
1038	glUniform1i(6, background->size);
1039	glUniform2i(7, background->x, yBase - y);
1040	glUniform3i(8, (background->priority << 3) + (background->index << 1) + 1, background->target1 | (background->target2 * 2), renderer->blendEffect);
1041	glVertexAttribPointer(0, 2, GL_INT, GL_FALSE, 0, _vertices);
1042	glEnableVertexAttribArray(0);
1043	glDrawBuffers(2, (GLenum[]) { GL_COLOR_ATTACHMENT0, GL_COLOR_ATTACHMENT1 });
1044	glDrawArrays(GL_TRIANGLE_FAN, 0, 4);
1045	glDrawBuffers(1, (GLenum[]) { GL_COLOR_ATTACHMENT0 });
1046
1047	_compositeLayer(renderer, background->tex, background->flags, y);
1048}
1049
1050void GBAVideoGLRendererDrawBackgroundMode2(struct GBAVideoGLRenderer* renderer, struct GBAVideoGLBackground* background, int y) {
1051	glBindFramebuffer(GL_FRAMEBUFFER, background->fbo);
1052	glViewport(0, 0, GBA_VIDEO_HORIZONTAL_PIXELS * renderer->scale, GBA_VIDEO_VERTICAL_PIXELS * renderer->scale);
1053	glScissor(0, y * renderer->scale, GBA_VIDEO_HORIZONTAL_PIXELS * renderer->scale, renderer->scale);
1054	glUseProgram(renderer->bgProgram[background->overflow ? 2 : 3]);
1055	glActiveTexture(GL_TEXTURE0);
1056	glBindTexture(GL_TEXTURE_2D, renderer->vramTex);
1057	glActiveTexture(GL_TEXTURE0 + 1);
1058	glBindTexture(GL_TEXTURE_2D, renderer->paletteTex);
1059	glUniform2i(0, 1, y);
1060	glUniform2i(1, GBA_VIDEO_HORIZONTAL_PIXELS, GBA_VIDEO_VERTICAL_PIXELS);
1061	glUniform1i(2, 0);
1062	glUniform1i(3, 1);
1063	glUniform1i(4, background->screenBase);
1064	glUniform1i(5, background->charBase);
1065	glUniform1i(6, background->size);
1066	glUniform3i(7, (background->priority << 3) + (background->index << 1) + 1, background->target1 | (background->target2 * 2), renderer->blendEffect);
1067	if (renderer->scale > 1) {
1068		glUniform2iv(8, 4, (GLint[]) {
1069			background->affine[0].sx, background->affine[0].sy,
1070			background->affine[1].sx, background->affine[1].sy,
1071			background->affine[2].sx, background->affine[2].sy,
1072			background->affine[3].sx, background->affine[3].sy,
1073		});
1074		glUniform2iv(12, 4, (GLint[]) {
1075			background->affine[0].dx, background->affine[0].dy,
1076			background->affine[1].dx, background->affine[1].dy,
1077			background->affine[2].dx, background->affine[2].dy,
1078			background->affine[3].dx, background->affine[3].dy,
1079		});
1080	} else {
1081		glUniform2iv(8, 4, (GLint[]) {
1082			background->affine[0].sx, background->affine[0].sy,
1083			background->affine[0].sx, background->affine[0].sy,
1084			background->affine[0].sx, background->affine[0].sy,
1085			background->affine[0].sx, background->affine[0].sy,
1086		});
1087		glUniform2iv(12, 4, (GLint[]) {
1088			background->affine[0].dx, background->affine[0].dy,
1089			background->affine[0].dx, background->affine[0].dy,
1090			background->affine[0].dx, background->affine[0].dy,
1091			background->affine[0].dx, background->affine[0].dy,
1092		});
1093	}
1094	glVertexAttribPointer(0, 2, GL_INT, GL_FALSE, 0, _vertices);
1095	glEnableVertexAttribArray(0);
1096	glDrawBuffers(2, (GLenum[]) { GL_COLOR_ATTACHMENT0, GL_COLOR_ATTACHMENT1 });
1097	glDrawArrays(GL_TRIANGLE_FAN, 0, 4);
1098	glDrawBuffers(1, (GLenum[]) { GL_COLOR_ATTACHMENT0 });
1099
1100	_compositeLayer(renderer, background->tex, background->flags, y);
1101}