I bought a gtx 670 so I could do shader debugging but I get an unexpected result with one of the most useful features, pixel history. When I click on the crosshair for the Front Left Color the result in the PH window always is “The specified pixel is not modified on or before the current event by any draw, clear, or blit calls”. This is using a ssao / deferred lighting chain of drawing commands so I don’t know why this message would come up.
How do I fix this?