GPU Pro 4

4. Tiled Forward Shading 109

// assign lights to 2D tiles

tiles2D = build_2d_tiles();

lightLists2D = assign_lights_to_2d_tiles( tiles2D );

// draw opaque geometry in pre -Z pass and find tiles ’

// extents in the Z- direction

depthBuffer = render_preZ_pass();

tileZBounds = reduce_z_bounds( tiles2D , depthBuffer );

// for transparent geometry , prune lights against maximum Z - direction

lightListsTrans

= prune_lights_max( lightLists2D , tileZBounds );

// for opaque geometry additionally prune lights against

// minimum Z -direction

lightListsOpaque

= prune_lights_min( lightListsTrans , tileZBounds );

// ...

// later : rendering

draw( opaque geometry , lightListsOpaque ...