ReactOS  0.4.14-dev-583-g2a1ba2c
sweep.h
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30 /*
31 ** Author: Eric Veach, July 1994.
32 **
33 */
34 
35 #ifndef __sweep_h_
36 #define __sweep_h_
37 
38 //#include "mesh.h"
39 
40 /* __gl_computeInterior( tess ) computes the planar arrangement specified
41  * by the given contours, and further subdivides this arrangement
42  * into regions. Each region is marked "inside" if it belongs
43  * to the polygon, according to the rule given by tess->windingRule.
44  * Each interior region is guaranteed be monotone.
45  */
47 
48 
49 /* The following is here *only* for access by debugging routines */
50 
51 //#include "dict.h"
52 
53 /* For each pair of adjacent edges crossing the sweep line, there is
54  * an ActiveRegion to represent the region between them. The active
55  * regions are kept in sorted order in a dynamic dictionary. As the
56  * sweep line crosses each vertex, we update the affected regions.
57  */
58 
59 struct ActiveRegion {
60  GLUhalfEdge *eUp; /* upper edge, directed right to left */
61  DictNode *nodeUp; /* dictionary node corresponding to eUp */
62  int windingNumber; /* used to determine which regions are
63  * inside the polygon */
64  GLboolean inside; /* is this region inside the polygon? */
65  GLboolean sentinel; /* marks fake edges at t = +/-infinity */
66  GLboolean dirty; /* marks regions where the upper or lower
67  * edge has changed, but we haven't checked
68  * whether they intersect yet */
69  GLboolean fixUpperEdge; /* marks temporary edges introduced when
70  * we process a "right vertex" (one without
71  * any edges leaving to the right) */
72 };
73 
74 #define RegionBelow(r) ((ActiveRegion *) dictKey(dictPred((r)->nodeUp)))
75 #define RegionAbove(r) ((ActiveRegion *) dictKey(dictSucc((r)->nodeUp)))
76 
77 #endif
GLboolean sentinel
Definition: sweep.h:65
int windingNumber
Definition: sweep.h:62
DictNode * nodeUp
Definition: sweep.h:61
unsigned char GLboolean
Definition: gl.h:151
GLboolean fixUpperEdge
Definition: sweep.h:69
GLboolean inside
Definition: sweep.h:64
GLUhalfEdge * eUp
Definition: sweep.h:60
int __gl_computeInterior(GLUtesselator *tess)
Definition: sweep.c:1301
GLboolean dirty
Definition: sweep.h:66