GPU PRO 3

214 III Global Illumination Effects

un if or m usampler1D bitmask;

va ry in g flo at mappedZ;

va ry in g ou t u ve c4 result;

voi d main ()

{

// Set bit in voxel grid

result = texture1D(bitmask , mappedZ );

}

Listing 3.3. Fill voxel grid (fragment shader).

bit that represents the voxel in the voxel grid. This is done with the help of a

one-dimensional texture, created on the CPU beforehand (please see the source

code or [Eisemann and D´ecoret 06] for full details). The lookup texture maps a

depth value to a bitmask representing a full voxel at that certain depth interval.

The fragment shader writes this bitmask to the render target and thus sets the

corresp ...