GPU Pro 4

120 II Rendering

for( int i =0; i <nBodies ; i +=64)

{

int il = lIdx + i;

if ( il < nBodies )

{

if (overlaps ( frustum , gLightGeometry[il]))

{

appendLightToList(il);

}

}

}

In overlaps(), a light-geometry overlap is checked against a frustum using the

separating axis theorem [Ericson 04]. If a light is overlapping the frustum, the

light index is stored to the list of the overlapping lights in

appendLightToList().

There are several data structures we can use to store the light list. The obvious

way would be to build a linked list using a few atomic operations [Yang et al. 10].

However, this approach is relatively expensive: we need to use a few global

atomic op ...