This is a simple Photon Mapping Rendering Engine for computing GI (Global Illumination) with particles in the Houdini.

Actually it's not a super fast rendering engine for 3D projects , I made this just for fun and my personal experiments , So I calling this FUNNY ENGINE !

Features :

1. Computing Indirect diffuse
2. Energy Conserving
3. Area and Mesh Lights
4. Control number of Photons from Rendering node and Lights.
5. Custom Materials
6. Using Emission value of Materials as light source
7. Color Correction possibility in Post Processing
8. Light's group for using in Post Processing
9. Supporting Textures for lights
10. All values are HDR
11. Channel filtering (R,G,B)
12. Linear Workflow for Lights (and sRGB for Colors and Textures)
13. Unlimited multiple lights
14. It's so funny !

How this work :

It's algorithm is so simple , each particle is photon , so the photons (particles) emitting from light source to models.
After hitting any photon to models , some different operation happening.

1. the Color of photon filtered by color of the model (e.g if photon is WHITE and model is RED , then GREEN and BLUE values from photon filtered by RED and only RED light reflected from surface)

2. Energy of the Photon reducing after each bouncing.

3. Energy of the Photon reducing by distance to light source.

4. After generating all photons , values of them transfer to the original models with filtering to achieve smoother result.

Video Link :

https://vimeo.com/151640128 [vimeo.com]