Fix draw buffers support.

src/OpenGL/libGLESv2/Context.cpp

@@ -733,10 +733,11 @@ void Context::setFramebufferReadBuffer(GLuint buf)
 
 void Context::setFramebufferDrawBuffers(GLsizei n, const GLenum *bufs)
 {
-	Framebuffer* drawFramebuffer = getDrawFramebuffer();
-	for(int i = 0; i < n; ++i)
+	Framebuffer *drawFramebuffer = getDrawFramebuffer();
+
+	for(int i = 0; i < MAX_COLOR_ATTACHMENTS; i++)
 	{
-		drawFramebuffer->setDrawBuffer(i, bufs[i]);
+		drawFramebuffer->setDrawBuffer(i, (i < n) ? bufs[i] : GL_NONE);
 	}
 }
 
@@ -2082,8 +2083,8 @@ template<typename T> bool Context::getIntegerv(GLenum pname, T *params) const
 			return false;
 		}
 		break;
-	case GL_DRAW_BUFFER0: // symbolic constant, initial value is GL_BACK​
-	case GL_DRAW_BUFFER1: // symbolic constant, initial value is GL_NONE
+	case GL_DRAW_BUFFER0:
+	case GL_DRAW_BUFFER1:
 	case GL_DRAW_BUFFER2:
 	case GL_DRAW_BUFFER3:
 	case GL_DRAW_BUFFER4:
@@ -2100,7 +2101,7 @@ template<typename T> bool Context::getIntegerv(GLenum pname, T *params) const
 	case GL_DRAW_BUFFER15:
 		*params = getDrawFramebuffer()->getDrawBuffer(pname - GL_DRAW_BUFFER0);
 		break;
-	case GL_MAJOR_VERSION: // integer, at least 3
+	case GL_MAJOR_VERSION:
 		if(clientVersion >= 3)
 		{
 			*params = clientVersion;
@@ -2116,7 +2117,7 @@ template<typename T> bool Context::getIntegerv(GLenum pname, T *params) const
 	case GL_MAX_ARRAY_TEXTURE_LAYERS: // GLint, at least 2048
 		*params = IMPLEMENTATION_MAX_TEXTURE_SIZE;
 		break;
-	case GL_MAX_COLOR_ATTACHMENTS: // integer, at least 8
+	case GL_MAX_COLOR_ATTACHMENTS:
 		*params = MAX_COLOR_ATTACHMENTS;
 		break;
 	case GL_MAX_COMBINED_FRAGMENT_UNIFORM_COMPONENTS: // integer, at least 50048
@@ -2129,8 +2130,7 @@ template<typename T> bool Context::getIntegerv(GLenum pname, T *params) const
 	case GL_MAX_COMBINED_VERTEX_UNIFORM_COMPONENTS: // integer, at least 50176
 		*params = MAX_COMBINED_VERTEX_UNIFORM_COMPONENTS;
 		break;
-	case GL_MAX_DRAW_BUFFERS: // integer, at least 8
-		UNIMPLEMENTED();
+	case GL_MAX_DRAW_BUFFERS:
 		*params = MAX_DRAW_BUFFERS;
 		break;
 	case GL_MAX_ELEMENT_INDEX:
@@ -2676,12 +2676,19 @@ bool Context::applyRenderTarget()
         return error(GL_INVALID_FRAMEBUFFER_OPERATION, false);
     }
 
-	for(int i = 0; i < MAX_DRAW_BUFFERS; ++i)
+	for(int i = 0; i < MAX_DRAW_BUFFERS; i++)
+	{
+		if(framebuffer->getDrawBuffer(i) != GL_NONE)
 		{
 			egl::Image *renderTarget = framebuffer->getRenderTarget(i);
 			device->setRenderTarget(i, renderTarget);
 			if(renderTarget) renderTarget->release();
 		}
+		else
+		{
+			device->setRenderTarget(i, nullptr);
+		}
+	}
 
     egl::Image *depthBuffer = framebuffer->getDepthBuffer();
     device->setDepthBuffer(depthBuffer);
@@ -2840,7 +2847,11 @@ void Context::applyState(GLenum drawMode)
 
     if(mMaskStateDirty)
     {
-		device->setColorWriteMask(0, es2sw::ConvertColorMask(mState.colorMaskRed, mState.colorMaskGreen, mState.colorMaskBlue, mState.colorMaskAlpha));
+		for(int i = 0; i < MAX_DRAW_BUFFERS; i++)
+		{
+			device->setColorWriteMask(i, es2sw::ConvertColorMask(mState.colorMaskRed, mState.colorMaskGreen, mState.colorMaskBlue, mState.colorMaskAlpha));
+		}
+
 		device->setDepthWriteEnable(mState.depthMask);
 
         mMaskStateDirty = false;

src/OpenGL/libGLESv2/Framebuffer.cpp

@@ -80,11 +80,6 @@ void Framebuffer::setColorbuffer(GLenum type, GLuint colorbuffer, GLuint index,
 {
 	mColorbufferType[index] = (colorbuffer != 0) ? type : GL_NONE;
 	mColorbufferPointer[index] = lookupRenderbuffer(type, colorbuffer, level, layer);
-	drawBuffer[index] = (colorbuffer != 0) ? GL_COLOR_ATTACHMENT0 + index : GL_NONE;
-	if(index == 0)
-	{
-		readBuffer = drawBuffer[0];
-	}
 }
 
 void Framebuffer::setDepthbuffer(GLenum type, GLuint depthbuffer, GLint level, GLint layer)

src/OpenGL/libGLESv2/libGLESv3.cpp

@@ -1137,11 +1137,6 @@ GL_APICALL void GL_APIENTRY glDrawBuffers(GLsizei n, const GLenum *bufs)
 		return error(GL_INVALID_VALUE);
 	}
 
-	if(n == 0)
-	{
-		return;
-	}
-
 	es2::Context *context = es2::getContext();
 
 	if(context)
@@ -1199,14 +1194,17 @@ GL_APICALL void GL_APIENTRY glDrawBuffers(GLsizei n, const GLenum *bufs)
 			case GL_COLOR_ATTACHMENT31:
 				{
 					GLuint index = (bufs[i] - GL_COLOR_ATTACHMENT0);
+
 					if(index >= MAX_COLOR_ATTACHMENTS)
 					{
-					return error(GL_INVALID_ENUM);
+						return error(GL_INVALID_OPERATION);
 					}
+
 					if(index != i)
 					{
 						return error(GL_INVALID_OPERATION);
 					}
+
 					if(drawFramebufferName == 0)
 					{
 						return error(GL_INVALID_OPERATION);