•Rigid rotation is 3x3 orthonormal matrix.
•3-D Translation is 3x4 matrix.
•3-D Translation + Rotation is 3x4 matrix.
•Scaled Orthographic Projection: Remove row three and allow scaling.
•Planar Object, remove column 3.
•Projective Transformations
–Rigid Rotation of Planar Object Represented by 3x3 matrix.
–When we write in homogeneous coordinates, projection implicit.
–When we drop rigidity, 3x3 matrix is arbitrary.
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