04/08/2003
15-462 Graphics I
2
Local vs. Global Illumination
•Local
illumination: Phong model
(OpenGL)
–Light
to surface to viewer
–No
shadows, interreflections
–Fast
enough for interactive graphics
•Global
illumination: Ray tracing
–Multiple
specular reflections and transmissions
–Only
one step of diffuse reflection
•Global
illumination: Radiosity
–All
diffuse interreflections; shadows
–Advanced:
combine with specular reflection