Don't fetch/serialise/apply render state if no context is bound.

* Note that we serialise out the new render state any time we reach a
  MakeCurrent call, so we can safely 'skip' the initial render state
  at the start of a frame.

renderdoc/driver/gl/gl_driver.h

@@ -55,7 +55,7 @@ struct GLInitParams : public RDCInitParams
 	uint32_t width;
 	uint32_t height;
 	
-	static const uint32_t GL_SERIALISE_VERSION = 0x0000008;
+	static const uint32_t GL_SERIALISE_VERSION = 0x0000009;
 
 	// version number internal to opengl stream
 	uint32_t SerialiseVersion;

renderdoc/driver/gl/gl_renderstate.cpp

@@ -259,6 +259,12 @@ void GLRenderState::FetchState(void *ctx, WrappedOpenGL *gl)
 	GLint boolread = 0;
 	// TODO check GL_MAX_*
 	// TODO check the extensions/core version for these is around
+
+	if(ctx == NULL)
+	{
+		ContextPresent = false;
+		return;
+	}
 	
 	{
 		GLenum pnames[] =
@@ -582,6 +588,9 @@ void GLRenderState::FetchState(void *ctx, WrappedOpenGL *gl)
 
 void GLRenderState::ApplyState(void *ctx, WrappedOpenGL *gl)
 {
+	if(!ContextPresent || ctx == NULL)
+		return;
+
 	{
 		GLenum pnames[] =
 		{
@@ -870,6 +879,8 @@ void GLRenderState::ApplyState(void *ctx, WrappedOpenGL *gl)
 
 void GLRenderState::Clear()
 {
+	ContextPresent = true;
+
 	RDCEraseEl(Enabled);
 	
 	RDCEraseEl(Tex1D);
@@ -957,6 +968,11 @@ void GLRenderState::Serialise(LogState state, void *ctx, WrappedOpenGL *gl)
 	GLResourceManager *rm = gl->GetResourceManager();
 	// TODO check GL_MAX_*
 
+	m_pSerialiser->Serialise("Context Present", ContextPresent);
+
+	if(!ContextPresent)
+		return;
+
 	m_pSerialiser->Serialise<eEnabled_Count>("GL_ENABLED", Enabled);
 
 	ResourceId ids[128];

renderdoc/driver/gl/gl_renderstate.h

@@ -100,6 +100,8 @@ struct GLRenderState
 		eEnabled_Count,
 	};
 
+	bool ContextPresent;
+
 	bool Enabled[eEnabled_Count];
 
 	uint32_t Tex1D[128];