Next: Homogeneous Clipping
Up: Projections and Projective
Previous: Mapping Z
- When do we clip in 3D? We should clip to the near plane
before we project. Otherwise, we might map z
to 0 and then x/z and y/z are undefined.
- We could clip to all 6 sides of the truncated viewing
pyramid. But the plane equations are simpler if
we clip after projection, because all sides of volume
are parallel to coordinate plane.
- Clipping to a plane in 3D is identical to clipping to a line
- We can also clip in homogenous coordinates.
Readings: Red Book, 6.6.4;
White book, 6.5.4.
CS488/688: Introduction to Interactive Computer Graphics
University of Waterloo
Computer Graphics Lab