DOC-20221115-WA0019..ppt
- 3. Perspective Projection In a perspective projection, the center of projection is at a finite distance from the viewing plane. Produces realistic views but does not preserve relative proportion of objects The size of a projection object is inversely proportional to its distance from the viewing plane.
- 4. Perspective Projection Parallel lines that are not parallel to the viewing plane, converge to a vanishing point. A vanishing point is the projection of a point at infinity.
- 5. Vanishing Points Each set of projected parallel lines will have a separate vanishing points. There are infinity many general vanishing points.
- 6. Perspective Projection The vanishing point for any set of lines that are parallel to one of the principal axes of an object is referred to as a principal vanishing point. We control the number of principal vanishing points (one, two, or three) with the orientation of the projection plane.
- 7. Perspective Projection The number of principal vanishing points in a projection is determined by the number of principal axes intersecting the view plane.
- 8. Perspective Projection One Point Perspective (z-axis vanishing point)
- 9. Perspective Projection Two Point Perspective (z, and x-axis vanishing points) y x z y x z
- 10. Perspective Projection Two Point Perspective
- 11. Perspective Projection Three Point Perspective (z, x, and y-axis vanishing points) y x z y x z
- 14. Summary