@@ -21,7 +21,7 @@ 1, 1,
 	0, 1
 };
 
-static void GBAGLContextInit(struct VideoBackend* v, unsigned width, unsigned height, WHandle handle) {
+static void GBAGLContextInit(struct VideoBackend* v, WHandle handle) {
 	UNUSED(handle);
 	struct GBAGLContext* context = (struct GBAGLContext*) v;
 	glGenTextures(1, &context->tex);
@@ -31,9 +31,14 @@ #ifndef _WIN32
 	glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
 	glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
 #endif
+}
+
+static void GBAGLContextSetDimensions(struct VideoBackend* v, unsigned width, unsigned height) {
+	struct GBAGLContext* context = (struct GBAGLContext*) v;
 	v->width = width;
 	v->height = height;
 
+	glBindTexture(GL_TEXTURE_2D, context->tex);
 #ifdef COLOR_16_BIT
 #ifdef COLOR_5_6_5
 	glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, toPow2(width), toPow2(height), 0, GL_RGB, GL_UNSIGNED_SHORT_5_6_5, 0);
@@ -113,6 +118,7 @@
 void GBAGLContextCreate(struct GBAGLContext* context) {
 	context->d.init = GBAGLContextInit;
 	context->d.deinit = GBAGLContextDeinit;
+	context->d.setDimensions = GBAGLContextSetDimensions;
 	context->d.resized = GBAGLContextResized;
 	context->d.swap = 0;
 	context->d.clear = GBAGLContextClear;

@@ -71,25 +71,13 @@ 1.f, 1.f,
 	1.f, -1.f,
 };
 
-static void GBAGLES2ContextInit(struct VideoBackend* v, unsigned width, unsigned height, WHandle handle) {
+static void GBAGLES2ContextInit(struct VideoBackend* v, WHandle handle) {
 	UNUSED(handle);
 	struct GBAGLES2Context* context = (struct GBAGLES2Context*) v;
 	glGenTextures(1, &context->tex);
 	glBindTexture(GL_TEXTURE_2D, context->tex);
 	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
 	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
-	v->width = width;
-	v->height = height;
-
-#ifdef COLOR_16_BIT
-#ifdef COLOR_5_6_5
-	glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, width, height, 0, GL_RGB, GL_UNSIGNED_SHORT_5_6_5, 0);
-#else
-	glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, width, height, 0, GL_RGBA, GL_UNSIGNED_SHORT_1_5_5_5_REV, 0);
-#endif
-#else
-	glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, width, height, 0, GL_RGBA, GL_UNSIGNED_BYTE, 0);
-#endif
 
 	glClearColor(0.f, 0.f, 0.f, 1.f);
 
@@ -142,6 +130,23 @@ glDeleteFramebuffers(1, &context->finalShader.fbo);
 	glDeleteTextures(1, &context->finalShader.tex);
 	context->finalShader.fbo = 0;
 	context->finalShader.tex = 0;
+}
+
+static void GBAGLES2ContextSetDimensions(struct VideoBackend* v, unsigned width, unsigned height) {
+	struct GBAGLES2Context* context = (struct GBAGLES2Context*) v;
+	v->width = width;
+	v->height = height;
+
+	glBindTexture(GL_TEXTURE_2D, context->tex);
+#ifdef COLOR_16_BIT
+#ifdef COLOR_5_6_5
+	glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, width, height, 0, GL_RGB, GL_UNSIGNED_SHORT_5_6_5, 0);
+#else
+	glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, width, height, 0, GL_RGBA, GL_UNSIGNED_SHORT_1_5_5_5_REV, 0);
+#endif
+#else
+	glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, width, height, 0, GL_RGBA, GL_UNSIGNED_BYTE, 0);
+#endif
 }
 
 static void GBAGLES2ContextDeinit(struct VideoBackend* v) {
@@ -312,6 +317,7 @@
 void GBAGLES2ContextCreate(struct GBAGLES2Context* context) {
 	context->d.init = GBAGLES2ContextInit;
 	context->d.deinit = GBAGLES2ContextDeinit;
+	context->d.setDimensions = GBAGLES2ContextSetDimensions;
 	context->d.resized = GBAGLES2ContextResized;
 	context->d.swap = 0;
 	context->d.clear = GBAGLES2ContextClear;

@@ -221,7 +221,7 @@ m_gl->makeCurrent();
 #if defined(_WIN32) && defined(USE_EPOXY)
 	epoxy_handle_external_wglMakeCurrent();
 #endif
-	m_backend->init(m_backend, VIDEO_HORIZONTAL_PIXELS, VIDEO_VERTICAL_PIXELS, reinterpret_cast<WHandle>(m_gl->winId()));
+	m_backend->init(m_backend, reinterpret_cast<WHandle>(m_gl->winId()));
 #if !defined(_WIN32) || defined(USE_EPOXY)
 	if (m_supportsShaders) {
 		m_shader.preprocessShader = static_cast<void*>(&reinterpret_cast<GBAGLES2Context*>(m_backend)->initialShader);
@@ -262,6 +262,19 @@ }
 
 void PainterGL::setContext(mCoreThread* context) {
 	m_context = context;
+
+	if (!context) {
+		return;
+	}
+
+	m_gl->makeCurrent();
+#if defined(_WIN32) && defined(USE_EPOXY)
+	epoxy_handle_external_wglMakeCurrent();
+#endif
+	unsigned width, height;
+	context->core->desiredVideoDimensions(context->core, &width, &height);
+	m_backend->setDimensions(m_backend, width, height);
+	m_gl->doneCurrent();
 }
 
 void PainterGL::setMessagePainter(MessagePainter* messagePainter) {
@@ -374,7 +387,9 @@ buffer = m_queue.dequeue();
 	} else {
 		buffer = m_free.takeLast();
 	}
-	memcpy(buffer, backing, VIDEO_HORIZONTAL_PIXELS * VIDEO_VERTICAL_PIXELS * BYTES_PER_PIXEL);
+	unsigned width, height;
+	m_context->core->desiredVideoDimensions(m_context->core, &width, &height);
+	memcpy(buffer, backing, width * height * BYTES_PER_PIXEL);
 	m_queue.enqueue(buffer);
 	m_mutex.unlock();
 }

@@ -34,8 +34,8 @@ using namespace std;
 
 GameController::GameController(QObject* parent)
 	: QObject(parent)
-	, m_drawContext(new uint32_t[VIDEO_VERTICAL_PIXELS * VIDEO_HORIZONTAL_PIXELS])
-	, m_frontBuffer(new uint32_t[VIDEO_VERTICAL_PIXELS * VIDEO_HORIZONTAL_PIXELS])
+	, m_drawContext(nullptr)
+	, m_frontBuffer(nullptr)
 	, m_threadContext()
 	, m_activeKeys(0)
 	, m_inactiveKeys(0)
@@ -116,7 +116,9 @@ };
 
 	m_threadContext.frameCallback = [](mCoreThread* context) {
 		GameController* controller = static_cast<GameController*>(context->userData);
-		memcpy(controller->m_frontBuffer, controller->m_drawContext, VIDEO_VERTICAL_PIXELS * VIDEO_HORIZONTAL_PIXELS * BYTES_PER_PIXEL);
+		unsigned width, height;
+		controller->m_threadContext.core->desiredVideoDimensions(controller->m_threadContext.core, &width, &height);
+		memcpy(controller->m_frontBuffer, controller->m_drawContext, width * height * BYTES_PER_PIXEL);
 		QMetaObject::invokeMethod(controller, "frameAvailable", Q_ARG(const uint32_t*, controller->m_frontBuffer));
 		if (controller->m_pauseAfterFrame.testAndSetAcquire(true, false)) {
 			mCoreThreadPauseFromThread(context);
@@ -208,8 +210,6 @@ disconnect();
 	clearMultiplayerController();
 	closeGame();
 	GBACheatDeviceDestroy(&m_cheatDevice);
-	delete[] m_drawContext;
-	delete[] m_frontBuffer;
 	delete m_backupLoadState;
 }
 
@@ -300,12 +300,17 @@ m_threadContext.core = GBACoreCreate();
 	}
 	m_threadContext.core->init(m_threadContext.core);
 
+	unsigned width, height;
+	m_threadContext.core->desiredVideoDimensions(m_threadContext.core, &width, &height);
+	m_drawContext = new uint32_t[width * height];
+	m_frontBuffer = new uint32_t[width * height];
+
 	if (!biosOnly) {
 		mCoreLoadFile(m_threadContext.core, m_fname.toUtf8().constData());
 		mCoreAutoloadSave(m_threadContext.core);
 	}
 
-	m_threadContext.core->setVideoBuffer(m_threadContext.core, m_drawContext, VIDEO_HORIZONTAL_PIXELS);
+	m_threadContext.core->setVideoBuffer(m_threadContext.core, m_drawContext, width);
 
 	if (!m_bios.isNull() && m_useBios) {
 		VFile* bios = VFileDevice::open(m_bios, O_RDONLY);
@@ -324,7 +329,7 @@ patch->close(patch);
 	}
 
 	m_inputController->recalibrateAxes();
-	memset(m_drawContext, 0xF8, VIDEO_VERTICAL_PIXELS * VIDEO_HORIZONTAL_PIXELS * 4);
+	memset(m_drawContext, 0xF8, width * height * 4);
 
 	m_threadContext.core->setAVStream(m_threadContext.core, m_stream);
 
@@ -422,6 +427,9 @@ mCoreThreadEnd(&m_threadContext);
 	mCoreThreadJoin(&m_threadContext);
 	// Make sure the event queue clears out before the thread is reused
 	QCoreApplication::processEvents();
+
+	delete[] m_drawContext;
+	delete[] m_frontBuffer;
 
 	m_patch = QString();
 

@@ -42,7 +42,8 @@ renderer->gl.d.user = renderer;
 	renderer->gl.d.lockAspectRatio = renderer->lockAspectRatio;
 	renderer->gl.d.filter = renderer->filter;
 	renderer->gl.d.swap = mSDLGLCommonSwap;
-	renderer->gl.d.init(&renderer->gl.d, renderer->width, renderer->height, 0);
+	renderer->gl.d.init(&renderer->gl.d, 0);
+	renderer->gl.d.setDimensions(&renderer->gl.d, renderer->width, renderer->height);
 
 	_doViewport(renderer->viewportWidth, renderer->viewportHeight, &renderer->gl.d);
 	return true;

@@ -102,6 +102,7 @@ renderer->gl2.d.lockAspectRatio = renderer->lockAspectRatio;
 	renderer->gl2.d.filter = renderer->filter;
 	renderer->gl2.d.swap = mSDLGLCommonSwap;
 	renderer->gl2.d.init(&renderer->gl2.d, 0);
+	renderer->gl2.d.setDimensions(&renderer->gl2.d, renderer->width, renderer->height);
 	return true;
 }
 

@@ -16,8 +16,9 @@ typedef void* WHandle;
 #endif
 
 struct VideoBackend {
-	void (*init)(struct VideoBackend*, unsigned width, unsigned height, WHandle handle);
+	void (*init)(struct VideoBackend*, WHandle handle);
 	void (*deinit)(struct VideoBackend*);
+	void (*setDimensions)(struct VideoBackend*, unsigned width, unsigned height);
 	void (*swap)(struct VideoBackend*);
 	void (*clear)(struct VideoBackend*);
 	void (*resized)(struct VideoBackend*, unsigned w, unsigned h);