Shadow Mapping
Description:
This program displays a simple scene, lit by a single light. The scene is first rendered from the light's point of view, and the depth values are loaded into a texture. This texture is then projected onto the scene as drawn from the eye's point of view, and a comparison with distance from the light is made. This determines shadowed regions.
This demo implements 8-bit "Dual Texture" shadow mapping and a 16-bit version using register combiners. 24-bit hardware shadow mapping is also demonstrated.
Requirements:
ARB_multitexture
EXT_texture_env_combine
Required for 16-bit shadow mapping:
NV_register_combiners
Required for hardware shadow mapping:
SGIX_depth_texture
SGIX_shadow
EXT_blend_minmax
References:
Shadow Mapping with Today's OpenGL Hardware, by Mark Kilgard. developer.nvidia.com
Projective Texture Mapping, by Cass Everitt. developer.nvidia.com
Hardware Shadow Mapping, by Cass Everitt. developer.nvidia.com
"Shadowcast" demo. developer.nvidia.com