Default drawBuffer/readBuffer for non default Framebuffer

src/OpenGL/libGLESv2/Context.cpp

@@ -1213,7 +1213,14 @@ void Context::bindReadFramebuffer(GLuint framebuffer)
 {
 	if(!getFramebuffer(framebuffer))
 	{
-		mFramebufferNameSpace.insert(framebuffer, new Framebuffer());
+		if(framebuffer == 0)
+		{
+			mFramebufferNameSpace.insert(framebuffer, new DefaultFramebuffer());
+		}
+		else
+		{
+			mFramebufferNameSpace.insert(framebuffer, new Framebuffer());
+		}
 	}
 
 	mState.readFramebuffer = framebuffer;
@@ -1223,7 +1230,14 @@ void Context::bindDrawFramebuffer(GLuint framebuffer)
 {
 	if(!getFramebuffer(framebuffer))
 	{
-		mFramebufferNameSpace.insert(framebuffer, new Framebuffer());
+		if(framebuffer == 0)
+		{
+			mFramebufferNameSpace.insert(framebuffer, new DefaultFramebuffer());
+		}
+		else
+		{
+			mFramebufferNameSpace.insert(framebuffer, new Framebuffer());
+		}
 	}
 
 	mState.drawFramebuffer = framebuffer;

src/OpenGL/libGLESv2/Framebuffer.cpp

@@ -39,8 +39,8 @@ Framebuffer::Framebuffer()
 	mDepthbufferType = GL_NONE;
 	mStencilbufferType = GL_NONE;
 
-	readBuffer = GL_BACK;
-	drawBuffer[0] = GL_BACK;
+	readBuffer = GL_COLOR_ATTACHMENT0;
+	drawBuffer[0] = GL_COLOR_ATTACHMENT0;
 	for(int i = 1; i < MAX_COLOR_ATTACHMENTS; ++i)
 	{
 		drawBuffer[i] = GL_NONE;
@@ -678,12 +678,20 @@ GLuint Framebuffer::getReadBufferIndex() const
 	}
 }
 
+DefaultFramebuffer::DefaultFramebuffer()
+{
+	readBuffer = GL_BACK;
+	drawBuffer[0] = GL_BACK;
+}
+
 DefaultFramebuffer::DefaultFramebuffer(Colorbuffer *colorbuffer, DepthStencilbuffer *depthStencil)
 {
 	GLenum defaultRenderbufferType = egl::getClientVersion() < 3 ? GL_RENDERBUFFER : GL_FRAMEBUFFER_DEFAULT;
 	mColorbufferPointer[0] = new Renderbuffer(0, colorbuffer);
 	mColorbufferType[0] = defaultRenderbufferType;
 
+	readBuffer = GL_BACK;
+	drawBuffer[0] = GL_BACK;
 	for(int i = 1; i < MAX_COLOR_ATTACHMENTS; i++)
 	{
 		mColorbufferPointer[i] = nullptr;

src/OpenGL/libGLESv2/Framebuffer.h

@@ -110,6 +110,7 @@ private:
 class DefaultFramebuffer : public Framebuffer
 {
 public:
+	DefaultFramebuffer();
 	DefaultFramebuffer(Colorbuffer *colorbuffer, DepthStencilbuffer *depthStencil);
 
 	bool isDefaultFramebuffer() const override { return true; }