Texture Mapping
- Put image on a quadrilateral (can be thought of as rectangle viewed in perspective)
- Map image to the square [-1,1]x[-1,1]
- Recall scan conversion: we traverse pixels along scan lines intersecting the quadrilateral; for a pixel p=[i,j] need to determine the pixel [m,n] in the image.
- to determine color, need the inverse of M : first, find the point q in the square which is mapped to p by M, second, find the pixel in the image that maps to q.