(a) UV shifting with relief mapping
- linear and binary search to calculate ray intersection with height_map
(b) 2 point light
- Diffuse direct lighting : Lambert
- Specular direct lighting : F(Schlick with Spherical Gaussian approximation), G(Schlick with Smith-like choise of k. [UE4]), D(GGX [UE4])
(c) 1 Image based lighting
- Diffuse indirect lighting : Irradiance SH from EnvMap
- Specular indirect lighting : Importance sampling of EnvMap based on GGX with QMC using Hammersley 2D samples [UE4] with "Horizon Occlusion for Normal Mapped Reflections"
(d) Emission
- emission_texture * emission_intensity
The difference between relief mapping and Parallax Occlusion Mapping
Difference
- Relief Mapping : linear and binary search, hard shadow
- Parallax Occlusion Mapping : linear search with surface-ray intersection, soft shadow
Notes of cascaded shadow maps
- DirectX SDK : CascadedShadowMaps11
- https://msdn.microsoft.com/en-us/library/windows/desktop/ee416307(v=vs.85).aspx
- https://msdn.microsoft.com/en-us/library/windows/desktop/ee416324(v=vs.85).aspx
- http://developer.download.nvidia.com/SDK/10.5/opengl/src/cascaded_shadow_maps/doc/cascaded_shadow_maps.pdf
- Light Perspective Shadow Maps : http://www.cg.tuwien.ac.at/research/vr/lispsm/shadows_egsr2004_revised.pdf
- Perspective Shadow Maps : http://http.developer.nvidia.com/GPUGems/gpugems_ch14.html
- Variance Shadow Maps : http://developer.download.nvidia.com/SDK/10/direct3d/Source/VarianceShadowMapping/Doc/VarianceShadowMapping.pdf