Graphics Reference
In-Depth Information
Figure 4.6.
The original scene (top) and the corresponding Hi-Z (Hierarchical-Z) buffer
(bottom) where the 2
×
2 minimum depths have been used successively to construct it.
It serves as an acceleration structure for our rays in screen space. Mip 0 is our depth
buffer that represents the scene depth per pixel. At each level we take the minimum of
2
×
2 pixels and produce this hierarchical representation of the depth values.
skipping empty space in the scene to eciently and quickly arrive at our de-
sired intersection point/coordinate by navigating in the different hierarchy levels.
Empty space in our case is the tiles we see in the image, the quads.
