GPU Pro 6

5. Real-Time Global Illumination Using Slices 287

S

0

S

1

S

2

S

3

S

4

Figure 5.18. Average position of the intersection points in each scene subset.

the locality of the blur. Note that the values T (p, q) are pairs of real values

{a, b}; they are scaled and added like 2D vectors.

7. Output the heightfield. Define the 2D table U

i

with the same dimensions

as T



i

. T



i

(p, q) is the pair {a, b}; the corresponding entry U

i

(p, q) is defined

to be a/b.Notethatb will be zero if and only if the b entry is zero for

all entries in table T

i

(see Figure 5.19). Note that the heightfields follow

the scene geometry where possible, and there is no heightfield in the s −s

1

subset.

In