Clément Foucault
dee94afd03
This adds an approximation of inverted AO by reversing the max horizon search (becoming a min horizon). The horizons are correctly clamped in the reverse direction to the shading and geometric normals. The arc integration is untouched as it seems to be symetrical. The limitation of this technique is that since it is still screen-space AO you don't get other hidden surfaces occlusion. This is more problematic in the case of inverted AO than for normal AO but it's better than no support AO. Support of distance parameter was easy thanks to recent AO refactor.