File indexing completed on 2024-04-14 14:11:10

 /*
 ** Author: Eric Veach, July 1994.
 **
 */
 
 #ifndef __sweep_h_
 #define __sweep_h_
 
 #include "mesh.h"
 
 /* __gl_computeInterior( tess ) computes the planar arrangement specified
  * by the given contours, and further subdivides this arrangement
  * into regions.  Each region is marked "inside" if it belongs
  * to the polygon, according to the rule given by tess->windingRule.
  * Each interior region is guaranteed be monotone.
  */
 int __gl_computeInterior(GLUtesselator *tess);
 
 /* The following is here *only* for access by debugging routines */
 
 #include "dict.h"
 
 /* For each pair of adjacent edges crossing the sweep line, there is
  * an ActiveRegion to represent the region between them.  The active
  * regions are kept in sorted order in a dynamic dictionary.  As the
  * sweep line crosses each vertex, we update the affected regions.
  */
 
 struct ActiveRegion
 {
     GLUhalfEdge *eUp;       /* upper edge, directed right to left */
     DictNode *nodeUp;       /* dictionary node corresponding to eUp */
     int windingNumber;      /* used to determine which regions are
                                  * inside the polygon */
     GLboolean inside;       /* is this region inside the polygon? */
     GLboolean sentinel;     /* marks fake edges at t = +/-infinity */
     GLboolean dirty;        /* marks regions where the upper or lower
                                  * edge has changed, but we haven't checked
                                  * whether they intersect yet */
     GLboolean fixUpperEdge; /* marks temporary edges introduced when
                                  * we process a "right vertex" (one without
                                  * any edges leaving to the right) */
 };
 
 #define RegionBelow(r) ((ActiveRegion *)dictKey(dictPred((r)->nodeUp)))
 #define RegionAbove(r) ((ActiveRegion *)dictKey(dictSucc((r)->nodeUp)))
 
 #endif