154
edits
Changes
→This Week
**: V - viewpoint vector
**:: V = norm(Camera<sub>position</sub> - Vertex<sub>position</sub>)
** Phong - account accurately for position of viewer
**: Specular reflectance = (R<sub>i</sub> . V)<sup>p<sub>i</sub></sup>
**: R<sub>i</sub> - reflection vector
**:: R<sub>i</sub> = 2 * (N . L<sub>dir<sub>i</sub></sub>) N - L<sub>dir<sub>i</sub></sub>
**: p<sub>i</sub> - true specular power of light i
**:
** Blinn-Phong - use halfway vector instead of reflection vector - adjust power to compensate
**: Specular reflectance = (N . H<sub>i</sub>)<sup>p'<sub>i</sub></sup>
**:: H<sub>i</sub> = norm([0,0,1] + L<sub>dir<sub>i</sub></sub>) - less computationally intensive - assumes that camera is at infinity along z axis
**: p'<sub>i</sub> - adjusted specular power of light i
**:
** [http://msdn.microsoft.com/en-us/library/bb172256%28v=VS.85%29.aspx Ambient]
