Spherical environment map
Spherical Environment Mapping (SEM) is one of the simplest reflection mapping techniques.
When the camera moves around the object, the reflection is not very realistic since the same image is always reflected.
The image is usually aligned with the camera, although you could align it to other directions. For example Mudbox aligns its SEMs to the light, or in Unreal you can align SEMs to the Up vector (world space) and other directions.
Also called MatCap or Lit Sphere.
- Matcaps for UE4 Unreal Engine Forum thread.
- UDK LitSpheres, world space and camera space Polycount Forum thread.
- MatCap Basics » ZBrush Docs Pixologic documentation.
- Mudbox Lit Sphere Autodesk video tutorial.
- Spherical Environment Mapping in Unreal 3 - by Norman 'Norman3D' Schaar
- The Art of Texturing Using The OpenGL Shading Language - Spherical Environment Mapping - by Jerome Guinot
- LitSpheres in Max viewport Polycount Forum thread has Max & Maya FX shaders and many example Lit Spheres.
- Toon/Comic Shader for 3ds Max by Till 'Rollin' Maginot supports LitSpheres. More info in the Polycount thread TF2 and TOON realtime viewport shader (3ds max).
- Mudbox Litspheres creation - by Pior 'pior' Oberson, timelapse video of him creating Lit Spheres.