<<< OpenGL coordinate systems and transformations | Index | >>> |
Normals are unit-length vectors pointing perpendicular to a surface.
Translating a surface does not change its normal.
While objects undergo rotations (and sometimes isometric, shape non-preserving scaling), we need to construct a 3x3 matrix that includes all rotations and isomertric scaling transformations to eye coordinates.
Perspective transformations should not be applied to normals.
<<< OpenGL coordinate systems and transformations | Index | >>> |