Remember what this
means.
• We are
representing moving a set of points, projecting
them into the image, and scaling them.
• Matrix
multiplication: take inner product between each row of S and each point. First row of S produces X coordinates, while second row produces Y.
• Projection
occurs because S has no third row.
• Translation
occurs with tx and ty.
• Scaling can
be encoded with a scale factor in S.
• The rest of
S must be allowing the object to rotate.
•