GPU Pro 6

2. Tile-Based Omnidirectional Shadows 335

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40

20

Time (ms)

0

1

Number of Lights

128

Tiled Cube

643216842

Figure 2.7. Frame times of tiled versus cube technique with an increasing number of

shadow-casting point light sources.

18000

16000

14000

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Number of Draws

0

1

Number of Lights

128

Tiled Cube

643216842

Figure 2.8. Number of CPU submitted draw calls to render shadow maps in tiled and

cube technique with an increasing number of shadow-casting point lights.

doing a hardware texture lookup in a cube map is faster than doing the proposed

lookup, this is not true for performing PCF to produce soft shadows. While for

336 IV Shadows ...