Das hier ist der entscheidende Post von JCL, das muss abgeändert werden:
Quote:

Yes, this is a bug in default.fx. It happens when you use <fog> and <view> at the same time in a shader.

Solution: Edit default.fx and replace

float4x4 matWorldView;

by:

#ifndef MATWORLDVIEW
float4x4 matWorldView;
#define MATWORLDVIEW
#endif

This ensures that matWorldView is only defined once.



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