AVAILABLE: General Polygon Clipper

AVAILABLE: General Polygon Clipper

Post by Alan Murt » Wed, 27 May 1998 04:00:00

I have just uploaded a new release of my gpc polygon clipper to:


This new release (v2.20) fixes some reliability problems present
in earlier versions, and adds exclusive-or to the set operations
which are available.

Here is a brief summary of its features:

  * Computes difference, intersection, exclusive-or and union.
  * Handles polygon sets of arbitrary complexity: multiple
    contours, self-intersections, holes, concavities.
  * Vertex ordering is arbitrary (clockwise / anticlockwise mix).
  * The clipper may generate contour descriptions or give tristrip
    based output.
  * Degenerate input regions and coincident veritces / edges are
    correctly processed.

As well as clipping, the software may be used to:

  * Merge together touching polygons.
  * Triangulate arbitrary concave / holed / self-intersecting

The clipper is written in C. Documentation is available online
via the above WWW link.

Alan Murta.



I would like to announce the beta release of a general polygon clipper
library (in C). The clipper can perform union, difference and
intersection operations on arbitrary polygon sets (multibpe contours,
holes, convex, self-intersecting etc).

There are a number of known bugs which will hopefully be remedied in
later releases. However, the clipper should work well for all but a few
pathological cases, and will hopefully be of use to the graphics
community in its present state.

The clipper may be found at:


Please read the release notes regarding my (lack of) support for this

Alan Murta.

2. Soft F/X 2.5 vs TruesSpace 2 ?

3. ANNOUNCE: General Polygon Clipper Library

4. POV: Bending an object

5. ANNOUNCE: General Polygon Clipper library

6. OpenGL and Rasterization

7. ANNOUNCE: General Polygon Clipper Library

8. Curvature projection

9. ANNOUNCE: General Polygon Clipper library

10. Implementation of general polygon clipper (Bala R. Vatti).

11. AVAILABLE: New polygon clipper release

12. AVAILABLE: 2D polygon clipper

13. ANNOUNCEMENT: Polygon clipper available