Shadow Rendering Techniques

Shadows are areas not reached by a light source, typically blocked by occluding objects. While straightforward in physics, shadow calculation in 3D rendering involves complex trade-offs between quality, performance, and memory usage.

Over time, various techniques have been developed to compute shadows in 3D environments. The following methods each offer different trade-offs between quality, performance, and implementation complexity.

• Shadow mapping

• Shadow volume

• Texture / Sprite / Blob shadows

• Planar shadows

• Raytraced shadows

• Spherical harmonic lighting

• Occlusion Interval Map

• Ambient Occlusion