# Chapter 27. Motion Blur as a Post-Processing Effect — Gilberto Rosado

- Source: https://developer.nvidia.com/gpugems/gpugems3/part-iv-image-effects/chapter-27-motion-blur-post-processing-effect
- Volume: GPU Gems 3
- Note: add-only excerpt; images omitted.

## Summary
Post-process motion blur without rewriting all shaders for velocity. Reconstruct world position from depth buffer + inverse view-projection; transform by previous frame VP; screen-space delta = velocity. Blur by sampling color along velocity and averaging.

Static/camera-only blur is free as post. Dynamic objects need separate velocity pass (current vs previous VP per pixel). Mask (alpha/separate RT) can keep cars sharp in racing games. Same depth→world trick also enables DoF/fog posts. Platforms without depth sampling can write depth to MRT/alpha.