GPU Pro 4

160 II Rendering

Since voxels are a simplified representation of the actual scene, detailed geo-

metric information is lost. In order to amplify color bleeding in the final global

illumination output, colors with high difference in their color channels (“con-

trast”) are preferred. By writing the contrast value into the highest 8 bit of the

integer color mask, colors with the highest contrast will dominate automatically,

since we write the results with an

InterlockedMax() into the voxel grid. Since,

e.g., thin geometry can have opposite normals in one single voxel, not only the

color but also the normal has to be carefully written into the voxels. Therefore ...