All about lighting in games.
Dota 2 Character Texture Guide by Valve Software, from Dota 2 Workshop shows how to use ambient occlusion and point light bakes to create the diffuse texture. File:Dota2CharacterTextureGuide.pdf(3MB pdf backup)
Practical Light and Color ($) by Jeremy Vickery - video by a lighting artist at Pixar
Light for Visual Artists: Understanding & Using Light in Art & Design ($) by Richard Yot
Color and Light: A Guide for the Realist Painter ($) by James Gurney - lighting from a painter's perspective, lavishly illustrated.
Painting With Light ($) by John Alton - cinematographer's guide to lighting.
Digital Lighting and Rendering ($) by Jeremy Birn - digital artist's guide to lighting.
Lighting Basics and You... thread on the Polycount Forum.
PSG Art tutorial by Arne Niklas Jansson
Tutorials: Does three point lighting suck? by Edu Martin Julve
Global Illumination (GI)
GI calculates how light touches objects in a scene, and bounces off (or through) to illuminate other objects nearby. Because light is scattered by these bounces, GI renders soft shadows and colored light bleeding, creating more realistic lighting.
Global illumination is expensive to render, but there are various approximations in use in games rendering...
Image Based Lighting (IBL)
Image based lighting surrounds the scene with a dome or sphere, which is mapped with an image. This image contributes lighting to everything inside it. Bright parts of the image create brighter lighting on the sides of objects that face that direction.
This is very fast to render, so it can be used in real-time.
IBL approximates global illumination, because the image can have multiple light sources, and can simulate light bouncing off distant surfaces to illuminate the scene objects. However it does not handle nearby light bounces... objects inside the scene don't bounce light onto each other.
Marmoset Toolbag and Skyshop are real-time rendering engines that use image based lighting.
Voxel Cone-Tracing Global Illumination
Recently attempted for the new Unreal Engine 4, but dropped due to the limitations of PlayStation 4 hardware.
Spherical Harmonic Lighting (SH)
Physically Based Rendering (PBR)
- Next gen Lighting on the Polycount Forum.