GPU Pro 6

3. Volumetric Fog and Lighting 237

Regular grid sampling Jittered grid sampling

Figure 3.13. Comparison of regular and jittered sampling patterns.

one layer of objects is stored (the depth buffer acts like a height field—we have

no information for objects behind it). Therefore, when reprojecting a dynamic

2D scene, occlusion artifacts are inevitable and there is a need to reconstruct

information for pixels that were not present in the previous frame (Figure 3.14).

In the case of volumetric reprojection, it is much easier, as we store informa-

tion for whole 3D viewing frustum in volumetric textures, as well as for the space

behind the shaded objects.