Screen space ambient occlusion

I recently wrote an SSAO shader to further enhance my renderer quality. This effect approximates global illumination by computing an ambient occlusion map in a post-processing pass.

The cost of this shader is relatively low for its benefits, and is independent of the scene complexity.

The image to the right shows:

• Blurred SSAO output
• Directional Lighting
• Lighting and SSAO

Framework:

• C#
• HLSL
• XNA

Features:

• Up to 32 samples per pixel
• Use normal information
• Smart blur to smooth out noise while preserving edges

Code samples:

• SSAO Shader
• Blur Shader

Sources:

• Finding Next Gen – CryEngine 2
• StarCraft II: Effects and Techniques
• GameDev forums