all repos — mgba @ 36c1fb59be4710543c4a5476a554757efe306ccd

mGBA Game Boy Advance Emulator

GB: Super Game Boy borders
Vicki Pfau vi@endrift.com
Tue, 01 Aug 2017 19:01:44 -0700
commit

36c1fb59be4710543c4a5476a554757efe306ccd

parent

55679df8fc49fca3d5f8584d16b90e9bb734a922

24 files changed, 523 insertions(+), 57 deletions(-)

jump to
M CHANGES → CHANGES 
@@ -4,6 +4,7 @@ - ELF support
  - Game Boy Camera support
  - Qt: Set default Game Boy colors
  - Game Boy Printer support
+ - Super Game Boy borders
 Bugfixes:
  - GB Audio: Make audio unsigned with bias (fixes mgba.io/i/749)
  - Python: Fix importing .gb or .gba before .core
M include/mgba/internal/gb/gb.h → include/mgba/internal/gb/gb.h 
@@ -44,6 +44,34 @@ GB_VECTOR_SIO = 0x58,
 	GB_VECTOR_KEYPAD = 0x60,
 };
 
+enum GBSGBCommand {
+	SGB_PAL01 = 0,
+	SGB_PAL23,
+	SGB_PAL03,
+	SGB_PAL12,
+	SGB_ATTR_BLK,
+	SGB_ATTR_LIN,
+	SGB_ATTR_DIV,
+	SGB_ATTR_CHR,
+	SGB_SOUND,
+	SGB_SOU_TRN,
+	SGB_PAL_SET,
+	SGB_PAL_TRN,
+	SGB_ATRC_EN,
+	SGB_TEST_EN,
+	SGB_PICON_EN,
+	SGB_DATA_SND,
+	SGB_DATA_TRN,
+	SGB_MLT_REG,
+	SGB_JUMP,
+	SGB_CHR_TRN,
+	SGB_PCT_TRN,
+	SGB_ATTR_TRN,
+	SGB_ATTR_SET,
+	SGB_MASK_EN,
+	SGB_OBJ_TRN
+};
+
 struct LR35902Core;
 struct mCoreSync;
 struct mAVStream;

@@ -75,6 +103,10 @@ uint32_t sramSize;
 	int sramDirty;
 	int32_t sramDirtAge;
 	bool sramMaskWriteback;
+
+	int sgbBit;
+	int currentSgbBits;
+	uint8_t sgbPacket[16];
 
 	struct mCoreCallbacksList coreCallbacks;
 	struct mAVStream* stream;
M include/mgba/internal/gb/renderers/software.h → include/mgba/internal/gb/renderers/software.h 
@@ -34,6 +34,9 @@ uint8_t currentWy;
 
 	GBRegisterLCDC lcdc;
 	enum GBModel model;
+
+	int sgbTransfer;
+	uint8_t sgbPacket[16];
 };
 
 void GBVideoSoftwareRendererCreate(struct GBVideoSoftwareRenderer*);
M include/mgba/internal/gb/video.h → include/mgba/internal/gb/video.h 
@@ -30,7 +30,11 @@ GB_VIDEO_MODE_1_LENGTH = 65664,
 	GB_VIDEO_TOTAL_LENGTH = 70224,
 
 	GB_BASE_MAP = 0x1800,
-	GB_SIZE_MAP = 0x0400
+	GB_SIZE_MAP = 0x0400,
+
+	SGB_SIZE_CHAR_RAM = 0x2000,
+	SGB_SIZE_MAP_RAM = 0x1000,
+	SGB_SIZE_PAL_RAM = 0x1000
 };
 
 DECL_BITFIELD(GBObjAttributes, uint8_t);

@@ -41,6 +45,13 @@ DECL_BIT(GBObjAttributes, XFlip, 5);
 DECL_BIT(GBObjAttributes, YFlip, 6);
 DECL_BIT(GBObjAttributes, Priority, 7);
 
+DECL_BITFIELD(SGBBgAttributes, uint16_t);
+DECL_BITS(SGBBgAttributes, Tile, 0, 10);
+DECL_BITS(SGBBgAttributes, Palette, 10, 3);
+DECL_BIT(SGBBgAttributes, Priority, 13);
+DECL_BIT(SGBBgAttributes, XFlip, 14);
+DECL_BIT(SGBBgAttributes, YFlip, 15);
+
 struct GBObj {
 	uint8_t y;
 	uint8_t x;

@@ -59,6 +70,7 @@ void (*init)(struct GBVideoRenderer* renderer, enum GBModel model);
 	void (*deinit)(struct GBVideoRenderer* renderer);
 
 	uint8_t (*writeVideoRegister)(struct GBVideoRenderer* renderer, uint16_t address, uint8_t value);
+	void (*writeSGBPacket)(struct GBVideoRenderer* renderer, uint8_t* data);
 	void (*writeVRAM)(struct GBVideoRenderer* renderer, uint16_t address);
 	void (*writePalette)(struct GBVideoRenderer* renderer, int index, uint16_t value);
 	void (*writeOAM)(struct GBVideoRenderer* renderer, uint16_t oam);

@@ -72,6 +84,11 @@
 	uint8_t* vram;
 	union GBOAM* oam;
 	struct mTileCache* cache;
+
+	uint8_t* sgbCharRam;
+	uint8_t* sgbMapRam;
+	uint8_t* sgbPalRam;
+	int sgbRenderMode;
 
 	bool disableBG;
 	bool disableOBJ;

@@ -145,6 +162,8 @@ void GBVideoWritePalette(struct GBVideo* video, uint16_t address, uint8_t value);
 void GBVideoSwitchBank(struct GBVideo* video, uint8_t value);
 
 void GBVideoSetPalette(struct GBVideo* video, unsigned index, uint32_t color);
+
+void GBVideoWriteSGBPacket(struct GBVideo* video, uint8_t* data);
 
 struct GBSerializedState;
 void GBVideoSerialize(const struct GBVideo* video, struct GBSerializedState* state);
M src/gb/core.c → src/gb/core.c 
@@ -190,9 +190,14 @@ #endif
 }
 
 static void _GBCoreDesiredVideoDimensions(struct mCore* core, unsigned* width, unsigned* height) {
-	UNUSED(core);
-	*width = GB_VIDEO_HORIZONTAL_PIXELS;
-	*height = GB_VIDEO_VERTICAL_PIXELS;
+	struct GB* gb = core->board;
+	if (!gb || gb->model != GB_MODEL_SGB) {
+		*width = GB_VIDEO_HORIZONTAL_PIXELS;
+		*height = GB_VIDEO_VERTICAL_PIXELS;
+	} else {
+		*width = 256;
+		*height = 224;
+	}
 }
 
 static void _GBCoreSetVideoBuffer(struct mCore* core, color_t* buffer, size_t stride) {
M src/gb/extra/proxy.c → src/gb/extra/proxy.c 
@@ -10,10 +10,12 @@ #include <mgba/internal/gb/gb.h>
 #include <mgba/internal/gb/io.h>
 
 #define BUFFER_OAM 1
+#define BUFFER_SGB 2
 
 static void GBVideoProxyRendererInit(struct GBVideoRenderer* renderer, enum GBModel model);
 static void GBVideoProxyRendererDeinit(struct GBVideoRenderer* renderer);
 static uint8_t GBVideoProxyRendererWriteVideoRegister(struct GBVideoRenderer* renderer, uint16_t address, uint8_t value);
+static void GBVideoProxyRendererWriteSGBPacket(struct GBVideoRenderer* renderer, uint8_t* data);
 static void GBVideoProxyRendererWriteVRAM(struct GBVideoRenderer* renderer, uint16_t address);
 static void GBVideoProxyRendererWriteOAM(struct GBVideoRenderer* renderer, uint16_t oam);
 static void GBVideoProxyRendererWritePalette(struct GBVideoRenderer* renderer, int address, uint16_t value);

@@ -30,6 +32,7 @@ void GBVideoProxyRendererCreate(struct GBVideoProxyRenderer* renderer, struct GBVideoRenderer* backend) {
 	renderer->d.init = GBVideoProxyRendererInit;
 	renderer->d.deinit = GBVideoProxyRendererDeinit;
 	renderer->d.writeVideoRegister = GBVideoProxyRendererWriteVideoRegister;
+	renderer->d.writeSGBPacket = GBVideoProxyRendererWriteSGBPacket;
 	renderer->d.writeVRAM = GBVideoProxyRendererWriteVRAM;
 	renderer->d.writeOAM = GBVideoProxyRendererWriteOAM;
 	renderer->d.writePalette = GBVideoProxyRendererWritePalette;

@@ -111,6 +114,7 @@ }
 
 static bool _parsePacket(struct mVideoLogger* logger, const struct mVideoLoggerDirtyInfo* item) {
 	struct GBVideoProxyRenderer* proxyRenderer = logger->context;
+	uint8_t sgbPacket[16];
 	switch (item->type) {
 	case DIRTY_REGISTER:
 		proxyRenderer->backend->writeVideoRegister(proxyRenderer->backend, item->address, item->value);

@@ -154,6 +158,11 @@ proxyRenderer->oamMax = 0;
 				return false;
 			}
 			logger->readData(logger, &proxyRenderer->objThisLine, item->value2, true);
+			break;
+		case BUFFER_SGB:
+			logger->readData(logger, sgbPacket, 16, true);
+			proxyRenderer->backend->writeSGBPacket(proxyRenderer->backend, sgbPacket);
+			break;
 		}
 		break;
 	case DIRTY_FLUSH:

@@ -177,6 +186,14 @@ if (!proxyRenderer->logger->block) {
 		proxyRenderer->backend->writeVideoRegister(proxyRenderer->backend, address, value);
 	}
 	return value;
+}
+
+void GBVideoProxyRendererWriteSGBPacket(struct GBVideoRenderer* renderer, uint8_t* data) {
+	struct GBVideoProxyRenderer* proxyRenderer = (struct GBVideoProxyRenderer*) renderer;
+	if (!proxyRenderer->logger->block) {
+		proxyRenderer->backend->writeSGBPacket(proxyRenderer->backend, data);
+	}
+	mVideoLoggerWriteBuffer(proxyRenderer->logger, BUFFER_SGB, 0, 16, data);
 }
 
 void GBVideoProxyRendererWriteVRAM(struct GBVideoRenderer* renderer, uint16_t address) {
M src/gb/gb.c → src/gb/gb.c 
@@ -28,6 +28,7 @@ static const uint8_t _knownHeader[4] = { 0xCE, 0xED, 0x66, 0x66};
 
 #define DMG_BIOS_CHECKSUM 0xC2F5CC97
 #define DMG_2_BIOS_CHECKSUM 0x59C8598E
+#define SGB_BIOS_CHECKSUM 0xEC8A83B9
 #define CGB_BIOS_CHECKSUM 0x41884E46
 
 mLOG_DEFINE_CATEGORY(GB, "GB", "gb");

@@ -384,6 +385,7 @@ bool GBIsBIOS(struct VFile* vf) {
 	switch (_GBBiosCRC32(vf)) {
 	case DMG_BIOS_CHECKSUM:
 	case DMG_2_BIOS_CHECKSUM:
+	case SGB_BIOS_CHECKSUM:
 	case CGB_BIOS_CHECKSUM:
 		return true;
 	default:

@@ -425,11 +427,11 @@ cpu->d = 0;
 
 	if (!gb->biosVf) {
 		switch (gb->model) {
-		case GB_MODEL_DMG:
-			// TODO: SGB
-		case GB_MODEL_SGB:
 		case GB_MODEL_AUTODETECT: // Silence warnings
 			gb->model = GB_MODEL_DMG;
+			// TODO: SGB registers
+		case GB_MODEL_SGB:
+		case GB_MODEL_DMG:
 			cpu->a = 1;
 			cpu->f.packed = 0xB0;
 			cpu->c = 0x13;

@@ -467,6 +469,10 @@ gb->memory.romSize = gb->yankedRomSize;
 		gb->yankedRomSize = 0;
 	}
 
+	gb->sgbBit = -1;
+	gb->currentSgbBits = 0;
+	memset(gb->sgbPacket, 0, sizeof(gb->sgbPacket));
+
 	mTimingClear(&gb->timing);
 
 	GBMemoryReset(gb);

@@ -491,6 +497,9 @@ case DMG_BIOS_CHECKSUM:
 		case DMG_2_BIOS_CHECKSUM:
 			gb->model = GB_MODEL_DMG;
 			break;
+		case SGB_BIOS_CHECKSUM:
+			gb->model = GB_MODEL_SGB;
+			break;
 		case CGB_BIOS_CHECKSUM:
 			gb->model = GB_MODEL_CGB;
 			break;

@@ -503,6 +512,8 @@ if (gb->model == GB_MODEL_AUTODETECT && gb->memory.rom) {
 		const struct GBCartridge* cart = (const struct GBCartridge*) &gb->memory.rom[0x100];
 		if (cart->cgb & 0x80) {
 			gb->model = GB_MODEL_CGB;
+		} else if (cart->sgb == 0x03 && cart->oldLicensee == 0x33) {
+			gb->model = GB_MODEL_SGB;
 		} else {
 			gb->model = GB_MODEL_DMG;
 		}
M src/gb/io.c → src/gb/io.c 
@@ -105,6 +105,33 @@ [REG_UNK75] = 0x8F,
 	[REG_IE]   = 0xE0,
 };
 
+static void _writeSGBBits(struct GB* gb, int bits) {
+	if (!bits) {
+		gb->sgbBit = 0;
+		memset(gb->sgbPacket, 0, sizeof(gb->sgbPacket));
+	}
+	if (bits == gb->currentSgbBits) {
+		return;
+	}
+	gb->currentSgbBits = bits;
+	if (gb->sgbBit == 128 && bits == 2) {
+		GBVideoWriteSGBPacket(&gb->video, gb->sgbPacket);
+		++gb->sgbBit;
+	}
+	if (gb->sgbBit >= 128) {
+		return;
+	}
+	switch (bits) {
+	case 1:
+		gb->sgbPacket[gb->sgbBit >> 3] |= 1 << (gb->sgbBit & 7);
+		// Fall through
+	case 2:
+		++gb->sgbBit;
+	default:
+		break;
+	}
+}
+
 void GBIOInit(struct GB* gb) {
 	memset(gb->memory.io, 0, sizeof(gb->memory.io));
 }

@@ -341,6 +368,10 @@ gb->audio.ch3.wavedata8[gb->audio.ch3.window >> 1] = value;
 		}
 		break;
 	case REG_JOYP:
+		if (gb->model == GB_MODEL_SGB) {
+			_writeSGBBits(gb, (value >> 4) & 3);
+		}
+		break;
 	case REG_TIMA:
 	case REG_TMA:
 		// Handled transparently by the registers

@@ -453,7 +484,8 @@ static uint8_t _readKeys(struct GB* gb) {
 	uint8_t keys = *gb->keySource;
 	switch (gb->memory.io[REG_JOYP] & 0x30) {
 	case 0x30:
-		keys = 0;
+	// TODO: Increment
+		keys = gb->model == GB_MODEL_SGB ? 0xF : 0;
 		break;
 	case 0x20:
 		keys >>= 4;
M src/gb/overrides.c → src/gb/overrides.c 
@@ -54,7 +54,7 @@ found = true;
 				override->model = GB_MODEL_AGB;
 			} else if (strcasecmp(model, "SGB") == 0) {
 				found = true;
-				override->model = GB_MODEL_DMG; // TODO
+				override->model = GB_MODEL_SGB;
 			} else if (strcasecmp(model, "MGB") == 0) {
 				found = true;
 				override->model = GB_MODEL_DMG; // TODO
M src/gb/renderers/software.c → src/gb/renderers/software.c 
@@ -7,11 +7,13 @@ #include <mgba/internal/gb/renderers/software.h>
 
 #include <mgba/core/tile-cache.h>
 #include <mgba/internal/gb/io.h>
+#include <mgba-util/math.h>
 #include <mgba-util/memory.h>
 
 static void GBVideoSoftwareRendererInit(struct GBVideoRenderer* renderer, enum GBModel model);
 static void GBVideoSoftwareRendererDeinit(struct GBVideoRenderer* renderer);
 static uint8_t GBVideoSoftwareRendererWriteVideoRegister(struct GBVideoRenderer* renderer, uint16_t address, uint8_t value);
+static void GBVideoSoftwareRendererWriteSGBPacket(struct GBVideoRenderer* renderer, uint8_t* data);
 static void GBVideoSoftwareRendererWritePalette(struct GBVideoRenderer* renderer, int index, uint16_t value);
 static void GBVideoSoftwareRendererWriteVRAM(struct GBVideoRenderer* renderer, uint16_t address);
 static void GBVideoSoftwareRendererWriteOAM(struct GBVideoRenderer* renderer, uint16_t oam);

@@ -25,9 +27,13 @@ static void GBVideoSoftwareRendererDrawBackground(struct GBVideoSoftwareRenderer* renderer, uint8_t* maps, int startX, int endX, int sx, int sy);
 static void GBVideoSoftwareRendererDrawObj(struct GBVideoSoftwareRenderer* renderer, struct GBObj* obj, int startX, int endX, int y);
 
 static void _clearScreen(struct GBVideoSoftwareRenderer* renderer) {
+	size_t sgbOffset = 0;
+	if (renderer->model == GB_MODEL_SGB) {
+		sgbOffset = renderer->outputBufferStride * 40 + 48;
+	}
 	int y;
 	for (y = 0; y < GB_VIDEO_VERTICAL_PIXELS; ++y) {
-		color_t* row = &renderer->outputBuffer[renderer->outputBufferStride * y];
+		color_t* row = &renderer->outputBuffer[renderer->outputBufferStride * y + sgbOffset];
 		int x;
 		for (x = 0; x < GB_VIDEO_HORIZONTAL_PIXELS; x += 4) {
 			row[x + 0] = renderer->palette[0];

@@ -38,10 +44,64 @@ }
 	}
 }
 
+static void _regenerateSGBBorder(struct GBVideoSoftwareRenderer* renderer) {
+	int  i;
+	for (i = 0; i < 0x40; ++i) {
+		uint16_t color;
+		LOAD_16LE(color, 0x800 + i * 2, renderer->d.sgbMapRam);
+		renderer->d.writePalette(&renderer->d, i + 0x40, color);
+	}
+	int x, y;
+	for (y = 0; y < 224; ++y) {
+		for (x = 0; x < 256; x += 8) {
+			uint16_t mapData;
+			LOAD_16LE(mapData, (x >> 2) + (y & ~7) * 8, renderer->d.sgbMapRam);
+			if (UNLIKELY(SGBBgAttributesGetTile(mapData) > 0x100)) {
+				continue;
+			}
+			int localY = y & 0x7;
+			if (SGBBgAttributesIsYFlip(mapData)) {
+				localY = 7 - y;
+			}
+			uint8_t tileData[4];
+			tileData[0] = renderer->d.sgbCharRam[(SGBBgAttributesGetTile(mapData) * 16 + localY) * 2 + 0x00];
+			tileData[1] = renderer->d.sgbCharRam[(SGBBgAttributesGetTile(mapData) * 16 + localY) * 2 + 0x01];
+			tileData[2] = renderer->d.sgbCharRam[(SGBBgAttributesGetTile(mapData) * 16 + localY) * 2 + 0x10];
+			tileData[3] = renderer->d.sgbCharRam[(SGBBgAttributesGetTile(mapData) * 16 + localY) * 2 + 0x11];
+			if (!(tileData[0] | tileData[1] | tileData[2] | tileData[3])) {
+				continue;
+			}
+
+			size_t base = y * renderer->outputBufferStride + x;
+			int p = SGBBgAttributesGetPalette(mapData) * 0x10;
+			if (SGBBgAttributesIsXFlip(mapData)) {
+				renderer->outputBuffer[base + 0] = renderer->palette[p | ((tileData[0] >> 0) & 0x1) | ((tileData[1] << 1) & 0x2) | ((tileData[2] << 2) & 0x4) | ((tileData[3] << 3) & 0x8)];
+				renderer->outputBuffer[base + 1] = renderer->palette[p | ((tileData[0] >> 1) & 0x1) | ((tileData[1] >> 0) & 0x2) | ((tileData[2] << 1) & 0x4) | ((tileData[3] << 2) & 0x8)];
+				renderer->outputBuffer[base + 2] = renderer->palette[p | ((tileData[0] >> 2) & 0x1) | ((tileData[1] >> 1) & 0x2) | ((tileData[2] >> 0) & 0x4) | ((tileData[3] << 1) & 0x8)];
+				renderer->outputBuffer[base + 3] = renderer->palette[p | ((tileData[0] >> 3) & 0x1) | ((tileData[1] >> 2) & 0x2) | ((tileData[2] >> 1) & 0x4) | ((tileData[3] >> 0) & 0x8)];
+				renderer->outputBuffer[base + 4] = renderer->palette[p | ((tileData[0] >> 4) & 0x1) | ((tileData[1] >> 3) & 0x2) | ((tileData[2] >> 2) & 0x4) | ((tileData[3] >> 1) & 0x8)];
+				renderer->outputBuffer[base + 5] = renderer->palette[p | ((tileData[0] >> 5) & 0x1) | ((tileData[1] >> 4) & 0x2) | ((tileData[2] >> 3) & 0x4) | ((tileData[3] >> 2) & 0x8)];
+				renderer->outputBuffer[base + 6] = renderer->palette[p | ((tileData[0] >> 6) & 0x1) | ((tileData[1] >> 5) & 0x2) | ((tileData[2] >> 4) & 0x4) | ((tileData[3] >> 3) & 0x8)];
+				renderer->outputBuffer[base + 7] = renderer->palette[p | ((tileData[0] >> 7) & 0x1) | ((tileData[1] >> 6) & 0x2) | ((tileData[2] >> 5) & 0x4) | ((tileData[3] >> 4) & 0x8)];
+			} else {
+				renderer->outputBuffer[base + 0] = renderer->palette[p | ((tileData[0] >> 7) & 0x1) | ((tileData[1] >> 6) & 0x2) | ((tileData[2] >> 5) & 0x4) | ((tileData[3] >> 4) & 0x8)];
+				renderer->outputBuffer[base + 1] = renderer->palette[p | ((tileData[0] >> 6) & 0x1) | ((tileData[1] >> 5) & 0x2) | ((tileData[2] >> 4) & 0x4) | ((tileData[3] >> 3) & 0x8)];
+				renderer->outputBuffer[base + 2] = renderer->palette[p | ((tileData[0] >> 5) & 0x1) | ((tileData[1] >> 4) & 0x2) | ((tileData[2] >> 3) & 0x4) | ((tileData[3] >> 2) & 0x8)];
+				renderer->outputBuffer[base + 3] = renderer->palette[p | ((tileData[0] >> 4) & 0x1) | ((tileData[1] >> 3) & 0x2) | ((tileData[2] >> 2) & 0x4) | ((tileData[3] >> 1) & 0x8)];
+				renderer->outputBuffer[base + 4] = renderer->palette[p | ((tileData[0] >> 3) & 0x1) | ((tileData[1] >> 2) & 0x2) | ((tileData[2] >> 1) & 0x4) | ((tileData[3] >> 0) & 0x8)];
+				renderer->outputBuffer[base + 5] = renderer->palette[p | ((tileData[0] >> 2) & 0x1) | ((tileData[1] >> 1) & 0x2) | ((tileData[2] >> 0) & 0x4) | ((tileData[3] << 1) & 0x8)];
+				renderer->outputBuffer[base + 6] = renderer->palette[p | ((tileData[0] >> 1) & 0x1) | ((tileData[1] >> 0) & 0x2) | ((tileData[2] << 1) & 0x4) | ((tileData[3] << 2) & 0x8)];
+				renderer->outputBuffer[base + 7] = renderer->palette[p | ((tileData[0] >> 0) & 0x1) | ((tileData[1] << 1) & 0x2) | ((tileData[2] << 2) & 0x4) | ((tileData[3] << 3) & 0x8)];
+			}
+		}
+	}
+}
+
 void GBVideoSoftwareRendererCreate(struct GBVideoSoftwareRenderer* renderer) {
 	renderer->d.init = GBVideoSoftwareRendererInit;
 	renderer->d.deinit = GBVideoSoftwareRendererDeinit;
 	renderer->d.writeVideoRegister = GBVideoSoftwareRendererWriteVideoRegister;
+	renderer->d.writeSGBPacket = GBVideoSoftwareRendererWriteSGBPacket;
 	renderer->d.writePalette = GBVideoSoftwareRendererWritePalette;
 	renderer->d.writeVRAM = GBVideoSoftwareRendererWriteVRAM;
 	renderer->d.writeOAM = GBVideoSoftwareRendererWriteOAM;

@@ -67,6 +127,7 @@ softwareRenderer->wy = 0;
 	softwareRenderer->currentWy = 0;
 	softwareRenderer->wx = 0;
 	softwareRenderer->model = model;
+	softwareRenderer->sgbTransfer = 0;
 }
 
 static void GBVideoSoftwareRendererDeinit(struct GBVideoRenderer* renderer) {

@@ -96,6 +157,11 @@ }
 	return value;
 }
 
+static void GBVideoSoftwareRendererWriteSGBPacket(struct GBVideoRenderer* renderer, uint8_t* data) {
+	struct GBVideoSoftwareRenderer* softwareRenderer = (struct GBVideoSoftwareRenderer*) renderer;
+	memcpy(softwareRenderer->sgbPacket, data, sizeof(softwareRenderer->sgbPacket));
+}
+
 static void GBVideoSoftwareRendererWritePalette(struct GBVideoRenderer* renderer, int index, uint16_t value) {
 	struct GBVideoSoftwareRenderer* softwareRenderer = (struct GBVideoSoftwareRenderer*) renderer;
 #ifdef COLOR_16_BIT

@@ -167,20 +233,60 @@ for (i = 0; i < oamMax; ++i) {
 			GBVideoSoftwareRendererDrawObj(softwareRenderer, &obj[i], startX, endX, y);
 		}
 	}
-	color_t* row = &softwareRenderer->outputBuffer[softwareRenderer->outputBufferStride * y];
+	size_t sgbOffset = 0;
+	if (softwareRenderer->model == GB_MODEL_SGB) {
+		sgbOffset = softwareRenderer->outputBufferStride * 40 + 48;
+	}
+	color_t* row = &softwareRenderer->outputBuffer[softwareRenderer->outputBufferStride * y + sgbOffset];
 	int x;
-	for (x = startX; x + 7 < (endX & ~7); x += 8) {
-		row[x] = softwareRenderer->palette[softwareRenderer->row[x] & 0x7F];
-		row[x + 1] = softwareRenderer->palette[softwareRenderer->row[x + 1] & 0x7F];
-		row[x + 2] = softwareRenderer->palette[softwareRenderer->row[x + 2] & 0x7F];
-		row[x + 3] = softwareRenderer->palette[softwareRenderer->row[x + 3] & 0x7F];
-		row[x + 4] = softwareRenderer->palette[softwareRenderer->row[x + 4] & 0x7F];
-		row[x + 5] = softwareRenderer->palette[softwareRenderer->row[x + 5] & 0x7F];
-		row[x + 6] = softwareRenderer->palette[softwareRenderer->row[x + 6] & 0x7F];
-		row[x + 7] = softwareRenderer->palette[softwareRenderer->row[x + 7] & 0x7F];
-	}
-	for (; x < endX; ++x) {
-		row[x] = softwareRenderer->palette[softwareRenderer->row[x] & 0x7F];
+	switch (softwareRenderer->d.sgbRenderMode) {
+	case 0:
+		for (x = startX; x + 7 < (endX & ~7); x += 8) {
+			row[x] = softwareRenderer->palette[softwareRenderer->row[x] & 0x7F];
+			row[x + 1] = softwareRenderer->palette[softwareRenderer->row[x + 1] & 0x7F];
+			row[x + 2] = softwareRenderer->palette[softwareRenderer->row[x + 2] & 0x7F];
+			row[x + 3] = softwareRenderer->palette[softwareRenderer->row[x + 3] & 0x7F];
+			row[x + 4] = softwareRenderer->palette[softwareRenderer->row[x + 4] & 0x7F];
+			row[x + 5] = softwareRenderer->palette[softwareRenderer->row[x + 5] & 0x7F];
+			row[x + 6] = softwareRenderer->palette[softwareRenderer->row[x + 6] & 0x7F];
+			row[x + 7] = softwareRenderer->palette[softwareRenderer->row[x + 7] & 0x7F];
+		}
+		for (; x < endX; ++x) {
+			row[x] = softwareRenderer->palette[softwareRenderer->row[x] & 0x7F];
+		}
+		break;
+	case 1:
+		return;
+	case 2:
+		for (x = startX; x + 7 < (endX & ~7); x += 8) {
+			row[x] = 0;
+			row[x + 1] = 0;
+			row[x + 2] = 0;
+			row[x + 3] = 0;
+			row[x + 4] = 0;
+			row[x + 5] = 0;
+			row[x + 6] = 0;
+			row[x + 7] = 0;
+		}
+		for (; x < endX; ++x) {
+			row[x] = 0;
+		}
+		return;
+	case 3:
+		for (x = startX; x + 7 < (endX & ~7); x += 8) {
+			row[x] = softwareRenderer->palette[0];
+			row[x + 1] = softwareRenderer->palette[0];
+			row[x + 2] = softwareRenderer->palette[0];
+			row[x + 3] = softwareRenderer->palette[0];
+			row[x + 4] = softwareRenderer->palette[0];
+			row[x + 5] = softwareRenderer->palette[0];
+			row[x + 6] = softwareRenderer->palette[0];
+			row[x + 7] = softwareRenderer->palette[0];
+		}
+		for (; x < endX; ++x) {
+			row[x] = softwareRenderer->palette[0];
+		}
+		return;
 	}
 }
 

@@ -189,6 +295,53 @@ struct GBVideoSoftwareRenderer* softwareRenderer = (struct GBVideoSoftwareRenderer*) renderer;
 	if (GBRegisterLCDCIsWindow(softwareRenderer->lcdc) && softwareRenderer->wy <= y && softwareRenderer->wx - 7 < GB_VIDEO_HORIZONTAL_PIXELS) {
 		++softwareRenderer->currentWy;
 	}
+	if (softwareRenderer->sgbTransfer == 1) {
+		uint8_t* buffer = NULL;
+		switch (softwareRenderer->sgbPacket[0] >> 3) {
+		case SGB_PAL_TRN:
+			buffer = renderer->sgbPalRam;
+			break;
+		case SGB_CHR_TRN:
+			buffer = &renderer->sgbCharRam[SGB_SIZE_CHAR_RAM / 2 * (softwareRenderer->sgbPacket[1] & 1)];
+			break;
+		case SGB_PCT_TRN:
+			buffer = renderer->sgbMapRam;
+			break;
+		default:
+			break;
+		}
+		if (buffer) {
+			size_t offset = 2 * ((y & 7) + (y >> 3) * GB_VIDEO_HORIZONTAL_PIXELS);
+			if (offset < 0x1000) {
+				int i;
+				for (i = 0; i < GB_VIDEO_HORIZONTAL_PIXELS; i += 8) {
+					if (UNLIKELY(offset + (i << 1) + 1 >= 0x1000)) {
+						break;
+					}
+					uint8_t hi = 0;
+					uint8_t lo = 0;
+					hi |= (softwareRenderer->row[i + 0] & 0x2) << 6;
+					lo |= (softwareRenderer->row[i + 0] & 0x1) << 7;
+					hi |= (softwareRenderer->row[i + 1] & 0x2) << 5;
+					lo |= (softwareRenderer->row[i + 1] & 0x1) << 6;
+					hi |= (softwareRenderer->row[i + 2] & 0x2) << 4;
+					lo |= (softwareRenderer->row[i + 2] & 0x1) << 5;
+					hi |= (softwareRenderer->row[i + 3] & 0x2) << 3;
+					lo |= (softwareRenderer->row[i + 3] & 0x1) << 4;
+					hi |= (softwareRenderer->row[i + 4] & 0x2) << 2;
+					lo |= (softwareRenderer->row[i + 4] & 0x1) << 3;
+					hi |= (softwareRenderer->row[i + 5] & 0x2) << 1;
+					lo |= (softwareRenderer->row[i + 5] & 0x1) << 2;
+					hi |= (softwareRenderer->row[i + 6] & 0x2) << 0;
+					lo |= (softwareRenderer->row[i + 6] & 0x1) << 1;
+					hi |= (softwareRenderer->row[i + 7] & 0x2) >> 1;
+					lo |= (softwareRenderer->row[i + 7] & 0x1) >> 0;
+					buffer[offset + (i << 1) + 0] = lo;
+					buffer[offset + (i << 1) + 1] = hi;
+				}
+			}
+		}
+	}
 }
 
 static void GBVideoSoftwareRendererFinishFrame(struct GBVideoRenderer* renderer) {

@@ -200,6 +353,34 @@ softwareRenderer->temporaryBuffer = 0;
 	}
 	if (!GBRegisterLCDCIsEnable(softwareRenderer->lcdc)) {
 		_clearScreen(softwareRenderer);
+	}
+	if (softwareRenderer->model == GB_MODEL_SGB) {
+		switch (softwareRenderer->sgbPacket[0] >> 3) {
+		case SGB_PAL_SET:
+			if (softwareRenderer->sgbPacket[9] & 0x40) {
+				renderer->sgbRenderMode = 0;
+			}
+			break;
+		case SGB_ATTR_SET:
+			if (softwareRenderer->sgbPacket[1] & 0x40) {
+				renderer->sgbRenderMode = 0;
+			}
+			break;
+		case SGB_PAL_TRN:
+		case SGB_CHR_TRN:
+		case SGB_PCT_TRN:
+			if (softwareRenderer->sgbTransfer > 0) {
+				// Make sure every buffer sees this if we're multibuffering
+				_regenerateSGBBorder(softwareRenderer);
+			}
+			++softwareRenderer->sgbTransfer;
+			if (softwareRenderer->sgbTransfer == 5) {
+				softwareRenderer->sgbTransfer = 0;
+				softwareRenderer->sgbPacket[0] = 0;
+			}
+		default:
+			break;
+		}
 	}
 	softwareRenderer->currentWy = 0;
 }
M src/gb/video.c → src/gb/video.c 
@@ -18,6 +18,7 @@
 static void GBVideoDummyRendererInit(struct GBVideoRenderer* renderer, enum GBModel model);
 static void GBVideoDummyRendererDeinit(struct GBVideoRenderer* renderer);
 static uint8_t GBVideoDummyRendererWriteVideoRegister(struct GBVideoRenderer* renderer, uint16_t address, uint8_t value);
+static void GBVideoDummyRendererWriteSGBPacket(struct GBVideoRenderer* renderer, uint8_t* data);
 static void GBVideoDummyRendererWritePalette(struct GBVideoRenderer* renderer, int index, uint16_t value);
 static void GBVideoDummyRendererWriteVRAM(struct GBVideoRenderer* renderer, uint16_t address);
 static void GBVideoDummyRendererWriteOAM(struct GBVideoRenderer* renderer, uint16_t oam);

@@ -39,6 +40,7 @@ static struct GBVideoRenderer dummyRenderer = {
 	.init = GBVideoDummyRendererInit,
 	.deinit = GBVideoDummyRendererDeinit,
 	.writeVideoRegister = GBVideoDummyRendererWriteVideoRegister,
+	.writeSGBPacket = GBVideoDummyRendererWriteSGBPacket,
 	.writeVRAM = GBVideoDummyRendererWriteVRAM,
 	.writeOAM = GBVideoDummyRendererWriteOAM,
 	.writePalette = GBVideoDummyRendererWritePalette,

@@ -52,6 +54,7 @@
 void GBVideoInit(struct GBVideo* video) {
 	video->renderer = &dummyRenderer;
 	video->renderer->cache = NULL;
+	video->renderer->sgbRenderMode = 0;
 	video->vram = 0;
 	video->frameskip = 0;
 

@@ -68,6 +71,10 @@ video->dmgPalette[0] = 0x7FFF;
 	video->dmgPalette[1] = 0x56B5;
 	video->dmgPalette[2] = 0x294A;
 	video->dmgPalette[3] = 0x0000;
+
+	video->renderer->sgbCharRam = NULL;
+	video->renderer->sgbMapRam = NULL;
+	video->renderer->sgbPalRam = NULL;
 }
 
 void GBVideoReset(struct GBVideo* video) {

@@ -89,6 +96,12 @@ memset(&video->oam, 0, sizeof(video->oam));
 	video->renderer->oam = &video->oam;
 	memset(&video->palette, 0, sizeof(video->palette));
 
+	if (video->p->model == GB_MODEL_SGB) {
+		video->renderer->sgbCharRam = anonymousMemoryMap(SGB_SIZE_CHAR_RAM);
+		video->renderer->sgbMapRam = anonymousMemoryMap(SGB_SIZE_MAP_RAM);
+		video->renderer->sgbPalRam = anonymousMemoryMap(SGB_SIZE_PAL_RAM);
+	}
+
 	video->renderer->deinit(video->renderer);
 	video->renderer->init(video->renderer, video->p->model);
 }

@@ -96,11 +109,27 @@
 void GBVideoDeinit(struct GBVideo* video) {
 	GBVideoAssociateRenderer(video, &dummyRenderer);
 	mappedMemoryFree(video->vram, GB_SIZE_VRAM);
+	if (video->renderer->sgbCharRam) {
+		mappedMemoryFree(video->renderer->sgbCharRam, SGB_SIZE_CHAR_RAM);
+		video->renderer->sgbCharRam = NULL;
+	}
+	if (video->renderer->sgbMapRam) {
+		mappedMemoryFree(video->renderer->sgbMapRam, SGB_SIZE_MAP_RAM);
+		video->renderer->sgbMapRam = NULL;
+	}
+	if (video->renderer->sgbPalRam) {
+		mappedMemoryFree(video->renderer->sgbPalRam, SGB_SIZE_PAL_RAM);
+		video->renderer->sgbPalRam = NULL;
+	}
 }
 
 void GBVideoAssociateRenderer(struct GBVideo* video, struct GBVideoRenderer* renderer) {
 	video->renderer->deinit(video->renderer);
 	renderer->cache = video->renderer->cache;
+	renderer->sgbRenderMode = video->renderer->sgbRenderMode;
+	renderer->sgbCharRam = video->renderer->sgbCharRam;
+	renderer->sgbMapRam = video->renderer->sgbMapRam;
+	renderer->sgbPalRam = video->renderer->sgbPalRam;
 	video->renderer = renderer;
 	renderer->vram = video->vram;
 	video->renderer->init(video->renderer, video->p->model);

@@ -372,7 +401,7 @@
 void GBVideoWriteSTAT(struct GBVideo* video, GBRegisterSTAT value) {
 	GBRegisterSTAT oldStat = video->stat;
 	video->stat = (video->stat & 0x7) | (value & 0x78);
-	if (video->p->model == GB_MODEL_DMG && !_statIRQAsserted(video, oldStat) && video->mode < 3) {
+	if (video->p->model < GB_MODEL_CGB && !_statIRQAsserted(video, oldStat) && video->mode < 3) {
 		// TODO: variable for the IRQ line value?
 		video->p->memory.io[REG_IF] |= (1 << GB_IRQ_LCDSTAT);
 		GBUpdateIRQs(video->p);

@@ -476,6 +505,96 @@ }
 	video->dmgPalette[index] = M_RGB8_TO_RGB5(color);
 }
 
+void GBVideoWriteSGBPacket(struct GBVideo* video, uint8_t* data) {
+	switch (data[0] >> 3) {
+	case SGB_PAL01:
+		video->palette[0] = data[1] | (data[2] << 8);
+		video->palette[1] = data[3] | (data[4] << 8);
+		video->palette[2] = data[5] | (data[6] << 8);
+		video->palette[3] = data[7] | (data[8] << 8);
+
+		video->palette[17] = data[9] | (data[10] << 8);
+		video->palette[18] = data[11] | (data[12] << 8);
+		video->palette[19] = data[13] | (data[14] << 8);
+		video->renderer->writePalette(video->renderer, 0, video->palette[0]);
+		video->renderer->writePalette(video->renderer, 1, video->palette[1]);
+		video->renderer->writePalette(video->renderer, 2, video->palette[2]);
+		video->renderer->writePalette(video->renderer, 3, video->palette[3]);
+		video->renderer->writePalette(video->renderer, 17, video->palette[17]);
+		video->renderer->writePalette(video->renderer, 18, video->palette[18]);
+		video->renderer->writePalette(video->renderer, 19, video->palette[19]);
+		break;
+	case SGB_PAL23:
+		video->palette[32] = data[1] | (data[2] << 8);
+		video->palette[33] = data[3] | (data[4] << 8);
+		video->palette[34] = data[5] | (data[6] << 8);
+		video->palette[35] = data[7] | (data[8] << 8);
+
+		video->palette[49] = data[9] | (data[10] << 8);
+		video->palette[50] = data[11] | (data[12] << 8);
+		video->palette[51] = data[13] | (data[14] << 8);
+		video->renderer->writePalette(video->renderer, 32, video->palette[32]);
+		video->renderer->writePalette(video->renderer, 33, video->palette[33]);
+		video->renderer->writePalette(video->renderer, 34, video->palette[34]);
+		video->renderer->writePalette(video->renderer, 35, video->palette[35]);
+		video->renderer->writePalette(video->renderer, 49, video->palette[49]);
+		video->renderer->writePalette(video->renderer, 50, video->palette[50]);
+		video->renderer->writePalette(video->renderer, 51, video->palette[51]);
+		break;
+	case SGB_PAL03:
+		video->palette[0] = data[1] | (data[2] << 8);
+		video->palette[1] = data[3] | (data[4] << 8);
+		video->palette[2] = data[5] | (data[6] << 8);
+		video->palette[3] = data[7] | (data[8] << 8);
+
+		video->palette[49] = data[9] | (data[10] << 8);
+		video->palette[50] = data[11] | (data[12] << 8);
+		video->palette[51] = data[13] | (data[14] << 8);
+		video->renderer->writePalette(video->renderer, 0, video->palette[0]);
+		video->renderer->writePalette(video->renderer, 1, video->palette[1]);
+		video->renderer->writePalette(video->renderer, 2, video->palette[2]);
+		video->renderer->writePalette(video->renderer, 3, video->palette[3]);
+		video->renderer->writePalette(video->renderer, 49, video->palette[49]);
+		video->renderer->writePalette(video->renderer, 50, video->palette[50]);
+		video->renderer->writePalette(video->renderer, 51, video->palette[51]);
+		break;
+	case SGB_PAL12:
+		video->palette[16] = data[1] | (data[2] << 8);
+		video->palette[17] = data[3] | (data[4] << 8);
+		video->palette[18] = data[5] | (data[6] << 8);
+		video->palette[19] = data[7] | (data[8] << 8);
+
+		video->palette[33] = data[9] | (data[10] << 8);
+		video->palette[34] = data[11] | (data[12] << 8);
+		video->palette[35] = data[13] | (data[14] << 8);
+		video->renderer->writePalette(video->renderer, 16, video->palette[16]);
+		video->renderer->writePalette(video->renderer, 17, video->palette[17]);
+		video->renderer->writePalette(video->renderer, 18, video->palette[18]);
+		video->renderer->writePalette(video->renderer, 19, video->palette[19]);
+		video->renderer->writePalette(video->renderer, 33, video->palette[33]);
+		video->renderer->writePalette(video->renderer, 34, video->palette[34]);
+		video->renderer->writePalette(video->renderer, 35, video->palette[35]);
+		break;
+	case SGB_MLT_REG:
+		return;
+	case SGB_MASK_EN:
+		video->renderer->sgbRenderMode = data[1] & 0x3;
+		break;
+	case SGB_PAL_TRN:
+	case SGB_CHR_TRN:
+	case SGB_PCT_TRN:
+		break;
+	case SGB_PAL_SET:
+	case SGB_ATTR_SET:
+		mLOG(GB, STUB, "Unimplemented SGB command: %02X", data[0] >> 3);
+		break;
+	default:
+		mLOG(GB, STUB, "Unimplemented SGB command: %02X", data[0] >> 3);
+		return;
+	}
+	video->renderer->writeSGBPacket(video->renderer, data);
+}
+
 static void GBVideoDummyRendererInit(struct GBVideoRenderer* renderer, enum GBModel model) {
 	UNUSED(renderer);
 	UNUSED(model);

@@ -491,6 +610,11 @@ static uint8_t GBVideoDummyRendererWriteVideoRegister(struct GBVideoRenderer* renderer, uint16_t address, uint8_t value) {
 	UNUSED(renderer);
 	UNUSED(address);
 	return value;
+}
+
+static void GBVideoDummyRendererWriteSGBPacket(struct GBVideoRenderer* renderer, uint8_t* data) {
+	UNUSED(renderer);
+	UNUSED(data);
 }
 
 static void GBVideoDummyRendererWriteVRAM(struct GBVideoRenderer* renderer, uint16_t address) {
M src/platform/3ds/main.c → src/platform/3ds/main.c 
@@ -285,7 +285,7 @@ _map3DSKey(&runner->core->inputMap, KEY_RIGHT, GBA_KEY_RIGHT);
 	_map3DSKey(&runner->core->inputMap, KEY_L, GBA_KEY_L);
 	_map3DSKey(&runner->core->inputMap, KEY_R, GBA_KEY_R);
 
-	outputBuffer = linearMemAlign(256 * VIDEO_VERTICAL_PIXELS * 2, 0x80);
+	outputBuffer = linearMemAlign(256 * 224 * 2, 0x80);
 	runner->core->setVideoBuffer(runner->core, outputBuffer, 256);
 
 	unsigned mode;
M src/platform/libretro/libretro.c → src/platform/libretro/libretro.c 
@@ -390,7 +390,7 @@ mCoreInitConfig(core, NULL);
 	core->init(core);
 	core->setAVStream(core, &stream);
 
-	outputBuffer = malloc(256 * VIDEO_VERTICAL_PIXELS * BYTES_PER_PIXEL);
+	outputBuffer = malloc(256 * 224 * BYTES_PER_PIXEL);
 	core->setVideoBuffer(core, outputBuffer, 256);
 
 	core->setAudioBufferSize(core, SAMPLES);
M src/platform/openemu/mGBAGameCore.m → src/platform/openemu/mGBAGameCore.m 
@@ -65,13 +65,9 @@ .useBios = true,
 		};
 		mCoreConfigLoadDefaults(&core->config, &opts);
 		core->init(core);
+		outputBuffer = nil;
 
-		unsigned width, height;
-		core->desiredVideoDimensions(core, &width, &height);
-		outputBuffer = malloc(width * height * BYTES_PER_PIXEL);
-		core->setVideoBuffer(core, outputBuffer, width);
 		core->setAudioBufferSize(core, SAMPLES);
-
 		cheatSets = [[NSMutableDictionary alloc] init];
 	}
 

@@ -108,6 +104,15 @@ }
 	mCoreAutoloadSave(core);
 
 	core->reset(core);
+
+	unsigned width, height;
+	core->desiredVideoDimensions(core, &width, &height);
+	if (outputBuffer) {
+		free(outputBuffer);
+	}
+	outputBuffer = malloc(width * height * BYTES_PER_PIXEL);
+	core->setVideoBuffer(core, outputBuffer, width);
+
 	return YES;
 }
M src/platform/opengl/gl.c → src/platform/opengl/gl.c 
@@ -110,12 +110,12 @@ struct mGLContext* context = (struct mGLContext*) v;
 	glBindTexture(GL_TEXTURE_2D, context->tex);
 #ifdef COLOR_16_BIT
 #ifdef COLOR_5_6_5
-	glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, v->width, v->height, GL_RGB, GL_UNSIGNED_SHORT_5_6_5, frame);
+	glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, toPow2(v->width), v->height, GL_RGB, GL_UNSIGNED_SHORT_5_6_5, frame);
 #else
-	glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, v->width, v->height, GL_RGBA, GL_UNSIGNED_SHORT_1_5_5_5_REV, frame);
+	glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, toPow2(v->width), v->height, GL_RGBA, GL_UNSIGNED_SHORT_1_5_5_5_REV, frame);
 #endif
 #else
-	glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, v->width, v->height,  GL_RGBA, GL_UNSIGNED_BYTE, frame);
+	glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, toPow2(v->width), v->height,  GL_RGBA, GL_UNSIGNED_BYTE, frame);
 #endif
 }
M src/platform/opengl/gles2.c → src/platform/opengl/gles2.c 
@@ -8,6 +8,7 @@
 #include <mgba/core/log.h>
 #include <mgba-util/configuration.h>
 #include <mgba-util/formatting.h>
+#include <mgba-util/math.h>
 #include <mgba-util/vector.h>
 #include <mgba-util/vfs.h>
 

@@ -190,13 +191,6 @@
 void _drawShader(struct mGLES2Context* context, struct mGLES2Shader* shader) {
 	GLint viewport[4];
 	glBindFramebuffer(GL_FRAMEBUFFER, shader->fbo);
-	if (shader->blend) {
-		glEnable(GL_BLEND);
-		glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
-	} else {
-		glDisable(GL_BLEND);
-		glClear(GL_COLOR_BUFFER_BIT);
-	}
 
 	glGetIntegerv(GL_VIEWPORT, viewport);
 	int drawW = shader->width;

@@ -222,6 +216,14 @@ drawW -= drawW % context->d.width;
 		drawH -= drawH % context->d.height;
 	}
 	glViewport(padW, padH, drawW, drawH);
+	if (shader->blend) {
+		glEnable(GL_BLEND);
+		glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
+	} else {
+		glDisable(GL_BLEND);
+		glClear(GL_COLOR_BUFFER_BIT);
+	}
+
 	if (shader->tex && (shader->width <= 0 || shader->height <= 0)) {
 		GLint oldTex;
 		glGetIntegerv(GL_TEXTURE_BINDING_2D, &oldTex);

@@ -316,6 +318,7 @@
 void mGLES2ContextPostFrame(struct VideoBackend* v, const void* frame) {
 	struct mGLES2Context* context = (struct mGLES2Context*) v;
 	glBindTexture(GL_TEXTURE_2D, context->tex);
+	glPixelStorei(GL_UNPACK_ROW_LENGTH, toPow2(v->width));
 #ifdef COLOR_16_BIT
 #ifdef COLOR_5_6_5
 	glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, v->width, v->height, 0, GL_RGB, GL_UNSIGNED_SHORT_5_6_5, frame);
M src/platform/qt/CoreController.cpp → src/platform/qt/CoreController.cpp 
@@ -25,6 +25,7 @@ #ifdef M_CORE_GB
 #include <mgba/internal/gb/gb.h>
 #include <mgba/internal/gb/renderers/tile-cache.h>
 #endif
+#include <mgba-util/math.h>
 #include <mgba-util/vfs.h>
 
 using namespace QGBA;

@@ -38,9 +39,11 @@ {
 	m_threadContext.core = core;
 	m_threadContext.userData = this;
 
-	QSize size = screenDimensions();
-	m_buffers[0].resize(size.width() * size.height() * sizeof(color_t));
-	m_buffers[1].resize(size.width() * size.height() * sizeof(color_t));
+	QSize size(256, 512);
+	m_buffers[0].resize(toPow2(size.width()) * size.height() * sizeof(color_t));
+	m_buffers[1].resize(toPow2(size.width()) * size.height() * sizeof(color_t));
+	m_buffers[0].fill(0xFF);
+	m_buffers[1].fill(0xFF);
 	m_activeBuffer = &m_buffers[0];
 
 	m_threadContext.core->setVideoBuffer(m_threadContext.core, reinterpret_cast<color_t*>(m_activeBuffer->data()), size.width());

@@ -81,7 +84,15 @@ action();
 		}
 		controller->m_resetActions.clear();
 
-		controller->m_activeBuffer->fill(0xFF);
+		QSize size = controller->screenDimensions();
+		controller->m_buffers[0].resize(toPow2(size.width()) * size.height() * sizeof(color_t));
+		controller->m_buffers[1].resize(toPow2(size.width()) * size.height() * sizeof(color_t));
+		controller->m_buffers[0].fill(0xFF);
+		controller->m_buffers[1].fill(0xFF);
+		controller->m_activeBuffer = &controller->m_buffers[0];
+
+		context->core->setVideoBuffer(context->core, reinterpret_cast<color_t*>(controller->m_activeBuffer->data()), toPow2(size.width()));
+
 		controller->finishFrame();
 	};
 

@@ -712,7 +723,7 @@ m_activeBuffer = &m_buffers[0];
 	if (m_activeBuffer == m_completeBuffer) {
 		m_activeBuffer = &m_buffers[1];
 	}
-	m_threadContext.core->setVideoBuffer(m_threadContext.core, reinterpret_cast<color_t*>(m_activeBuffer->data()), screenDimensions().width());
+	m_threadContext.core->setVideoBuffer(m_threadContext.core, reinterpret_cast<color_t*>(m_activeBuffer->data()), toPow2(screenDimensions().width()));
 
 	for (auto& action : m_frameActions) {
 		action();
M src/platform/qt/DisplayGL.cpp → src/platform/qt/DisplayGL.cpp 
@@ -14,6 +14,7 @@ #include <QResizeEvent>
 #include <QTimer>
 
 #include <mgba/core/core.h>
+#include <mgba-util/math.h>
 #ifdef BUILD_GL
 #include "platform/opengl/gl.h"
 #endif

@@ -390,7 +391,7 @@ } else {
 		buffer = m_free.takeLast();
 	}
 	QSize size = m_context->screenDimensions();
-	memcpy(buffer, backing, size.width() * size.height() * BYTES_PER_PIXEL);
+	memcpy(buffer, backing, toPow2(size.width()) * size.height() * BYTES_PER_PIXEL);
 	m_queue.enqueue(buffer);
 	m_mutex.unlock();
 }
M src/platform/qt/DisplayQt.cpp → src/platform/qt/DisplayQt.cpp 
@@ -11,6 +11,7 @@ #include <QPainter>
 
 #include <mgba/core/core.h>
 #include <mgba/core/thread.h>
+#include <mgba-util/math.h>
 
 using namespace QGBA;
 

@@ -56,12 +57,12 @@ return;
 	}
 #ifdef COLOR_16_BIT
 #ifdef COLOR_5_6_5
-	m_backing = QImage(reinterpret_cast<const uchar*>(buffer), m_width, m_height, QImage::Format_RGB16);
+	m_backing = QImage(reinterpret_cast<const uchar*>(buffer), toPow2(m_width), m_height, QImage::Format_RGB16);
 #else
-	m_backing = QImage(reinterpret_cast<const uchar*>(buffer), m_width, m_height, QImage::Format_RGB555);
+	m_backing = QImage(reinterpret_cast<const uchar*>(buffer), toPow2(m_width), m_height, QImage::Format_RGB555);
 #endif
 #else
-	m_backing = QImage(reinterpret_cast<const uchar*>(buffer), m_width, m_height, QImage::Format_ARGB32);
+	m_backing = QImage(reinterpret_cast<const uchar*>(buffer), toPow2(m_width), m_height, QImage::Format_ARGB32);
 	m_backing = m_backing.convertToFormat(QImage::Format_RGB32);
 #endif
 }
M src/platform/qt/OverrideView.cpp → src/platform/qt/OverrideView.cpp 
@@ -51,6 +51,7 @@ if (s_gbModelList.isEmpty()) {
 		// NB: Keep in sync with OverrideView.ui
 		s_gbModelList.append(GB_MODEL_AUTODETECT);
 		s_gbModelList.append(GB_MODEL_DMG);
+		s_gbModelList.append(GB_MODEL_SGB);
 		s_gbModelList.append(GB_MODEL_CGB);
 		s_gbModelList.append(GB_MODEL_AGB);
 	}
M src/platform/qt/OverrideView.ui → src/platform/qt/OverrideView.ui 
@@ -255,6 +255,11 @@ </property>
          </item>
          <item>
           <property name="text">
+           <string>Super Game Boy (SGB)</string>
+          </property>
+         </item>
+         <item>
+          <property name="text">
            <string>Game Boy Color (CGB)</string>
           </property>
          </item>
M src/platform/sdl/gl-sdl.c → src/platform/sdl/gl-sdl.c 
@@ -9,6 +9,8 @@ #include "gl-common.h"
 
 #include <mgba/core/core.h>
 #include <mgba/core/thread.h>
+#include <mgba-util/math.h>
+
 #include "platform/opengl/gl.h"
 
 static void _doViewport(int w, int h, struct VideoBackend* v) {

@@ -31,9 +33,10 @@
 bool mSDLGLInit(struct mSDLRenderer* renderer) {
 	mSDLGLCommonInit(renderer);
 
-	renderer->outputBuffer = malloc(renderer->width * renderer->height * BYTES_PER_PIXEL);
-	memset(renderer->outputBuffer, 0, renderer->width * renderer->height * BYTES_PER_PIXEL);
-	renderer->core->setVideoBuffer(renderer->core, renderer->outputBuffer, renderer->width);
+	size_t size = toPow2(renderer->width) * renderer->height * BYTES_PER_PIXEL;
+	renderer->outputBuffer = malloc(size);
+	memset(renderer->outputBuffer, 0, size);
+	renderer->core->setVideoBuffer(renderer->core, renderer->outputBuffer, toPow2(renderer->width));
 
 	mGLContextCreate(&renderer->gl);
 	renderer->gl.d.user = renderer;

@@ -64,6 +67,9 @@ _doViewport(renderer->viewportWidth, renderer->viewportHeight, v);
 				renderer->player.windowUpdated = 0;
 			}
 #endif
+			if (renderer->width != v->width || renderer->height != v->height) {
+				renderer->gl.d.setDimensions(&renderer->gl.d, renderer->width, renderer->height);
+			}
 		}
 
 		if (mCoreSyncWaitFrameStart(&context->impl->sync)) {
M src/platform/sdl/gles2-sdl.c → src/platform/sdl/gles2-sdl.c 
@@ -98,13 +98,14 @@ #else
 	mSDLGLCommonInit(renderer);
 #endif
 
+	size_t size = toPow2(renderer->width) * renderer->height * BYTES_PER_PIXEL;
 #ifndef __APPLE__
-	renderer->outputBuffer = memalign(16, renderer->width * renderer->height * BYTES_PER_PIXEL);
+	renderer->outputBuffer = memalign(16, size);
 #else
-	posix_memalign((void**) &renderer->outputBuffer, 16, renderer->width * renderer->height * BYTES_PER_PIXEL);
+	posix_memalign((void**) &renderer->outputBuffer, 16, size);
 #endif
-	memset(renderer->outputBuffer, 0, renderer->width * renderer->height * BYTES_PER_PIXEL);
-	renderer->core->setVideoBuffer(renderer->core, renderer->outputBuffer, renderer->width);
+	memset(renderer->outputBuffer, 0, size);
+	renderer->core->setVideoBuffer(renderer->core, renderer->outputBuffer, toPow2(renderer->width));
 
 	mGLES2ContextCreate(&renderer->gl2);
 	renderer->gl2.d.user = renderer;
M src/platform/sdl/main.c → src/platform/sdl/main.c 
@@ -220,6 +220,13 @@
 	bool didFail = !mCoreThreadStart(&thread);
 	if (!didFail) {
 #if SDL_VERSION_ATLEAST(2, 0, 0)
+		renderer->core->desiredVideoDimensions(renderer->core, &renderer->width, &renderer->height);
+		unsigned width = renderer->width * renderer->ratio;
+		unsigned height = renderer->height * renderer->ratio;
+		if (width != (unsigned) renderer->viewportWidth && height != (unsigned) renderer->viewportHeight) {
+			SDL_SetWindowSize(renderer->window, width, height);
+			renderer->player.windowUpdated = 1;
+		}
 		mSDLSetScreensaverSuspendable(&renderer->events, renderer->core->opts.suspendScreensaver);
 		mSDLSuspendScreensaver(&renderer->events);
 #endif