Sphere Map Specific Math (1)
Project Reflection Vector to 2D
- Reflection vector is unit vector
- (rx, ry, rz) where rx2 + ry2 + rz2 = 1
- Implies range of [-1, +1]
- Assumed in eye-space
- Project 3D vector into 2D (flatten)
- s´ = rX / ? rX2 + rY2 + (rZ+1)2
- t´ = rY / ? rX2 + rY2 + (rZ+1)2
- s’ and t’ remain in [-1 .. +1] range