Hi, im just attempting to use the nv_occlusion extension, and im finding it difficult to get an acceptable boost out of it. Basically my loop consists of drawing the land, then testing objects against it that are greater than 100 polygons. Then I readback the pixel counts from the various tests and clip objects as necesary. After I do not clear the depth buffer since the occlusion tests do not write depth, and I render the non occluded objects. Now even in a scene where I am rendering 20000 polygons less(including polys for occlusion test) occlusion testing is still faster than rendering the 20000 (bumpmapped diffuse and specular) polygons.The scene consists of about 100k polygons.
Now is 20000 polygons not an acceptable geometry loss for occlusion culling to work, or is occlusion culling only usefull in scenes where millions of polygons can be avoided?
Does anybody have any successfull stories in practical applications with 100-150k polys per scene - occluded polys?