OcclusionQuery::GetUnoccludedArea

Returns the area that was unoccluded during an occlusion query.

float GetUnoccludedArea(void) const;

The GetUnoccludedArea function returns the area that was unoccluded during an occlusion query as a fraction of the total viewport area for the current camera. The return value is always in the range [0.0, 1.0], where a value of 0.0 means that no fragments passed the depth test, and a value of 1.0 means that the entire viewport was filled with fragments that did pass the depth test.

OcclusionQuery::SetRenderCallback