I have a parametric representation of a cylindrical shape (well, it's like a cone, but its spike is trimmed). I would like to have an analytic expression for its silhouette lines in terms of the shape's parameters. The parameters I use are:
- Top circle center
- Bottom circle center
- Top circle radius
- Bottom circle radius
Note that the choice of top/bottom is arbitrary. I just call one side top and the other one bottom.
Thanks!
Update:
The silhouette, of course, is dependent on the viewpoint of the viewer. I assume an orthographic projection, and I know the viewer's position, look direction and up direction.