Started work on BeginRenderPass, enough to get a clear screen!

src/Refresh_Driver_D3D11.c

@@ -857,14 +857,62 @@ static void D3D11_BeginRenderPass(
 	uint32_t colorAttachmentCount,
 	Refresh_DepthStencilAttachmentInfo *depthStencilAttachmentInfo
 ) {
-	NOT_IMPLEMENTED
+	D3D11Renderer *renderer = (D3D11Renderer*) driverData;
+	D3D11CommandBuffer *cmdbuf = (D3D11CommandBuffer*) commandBuffer;
+	D3D11Texture *texture;
+	float clearColors[4];
+	ID3D11RenderTargetView *rtViews[MAX_COLOR_TARGET_BINDINGS];
+	ID3D11DepthStencilView *dsView = NULL;
+	D3D11_VIEWPORT viewports[1];
+	D3D11_RECT scissorRects[1];
+	uint8_t i;
+
+	/* Get the RTVs for each color attachment. */
+	for (i = 0; i < colorAttachmentCount; i += 1)
+	{
+		rtViews[i] = ((D3D11Texture*) colorAttachmentInfos[i].texture)->rtv;
+	}
+
+	/* FIXME: Get the DSV for the depth stencil attachment, if one exists! */
+
+	/* Set the render targets. */
+	ID3D11DeviceContext_OMSetRenderTargets(
+		cmdbuf->context,
+		colorAttachmentCount,
+		rtViews,
+		NULL
+	);
+
+	/* Perform load ops on those render targets. */
+	for (i = 0; i < colorAttachmentCount; i += 1)
+	{
+		texture = (D3D11Texture*) colorAttachmentInfos[i].texture;
+
+		if (colorAttachmentInfos[i].loadOp == REFRESH_LOADOP_CLEAR)
+		{
+			clearColors[0] = colorAttachmentInfos[i].clearColor.x;
+			clearColors[1] = colorAttachmentInfos[i].clearColor.y;
+			clearColors[2] = colorAttachmentInfos[i].clearColor.z;
+			clearColors[3] = colorAttachmentInfos[i].clearColor.w;
+
+			ID3D11DeviceContext_ClearRenderTargetView(
+				cmdbuf->context,
+				texture->rtv,
+				clearColors
+			);
+		}
+	}
+
+	/* FIXME: Set viewport and scissor state */
+
+	/* FIXME: What should we do with render area? */
 }
 
 static void D3D11_EndRenderPass(
 	Refresh_Renderer* driverData,
 	Refresh_CommandBuffer* commandBuffer
 ) {
-	NOT_IMPLEMENTED
+	/* FIXME: What should we do here? */
 }
 
 static void D3D11_BindGraphicsPipeline(