Stellarium  0.90.0
tessmono.h
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30 /*
31 ** Author: Eric Veach, July 1994.
32 **
33 */
34 
35 #ifndef __tessmono_h_
36 #define __tessmono_h_
37 
38 /* __gl_meshTessellateMonoRegion( face ) tessellates a monotone region
39  * (what else would it do??) The region must consist of a single
40  * loop of half-edges (see mesh.h) oriented CCW. "Monotone" in this
41  * case means that any vertical line intersects the interior of the
42  * region in a single interval.
43  *
44  * Tessellation consists of adding interior edges (actually pairs of
45  * half-edges), to split the region into non-overlapping triangles.
46  *
47  * __gl_meshTessellateInterior( mesh ) tessellates each region of
48  * the mesh which is marked "inside" the polygon. Each such region
49  * must be monotone.
50  *
51  * __gl_meshDiscardExterior( mesh ) zaps (ie. sets to NULL) all faces
52  * which are not marked "inside" the polygon. Since further mesh operations
53  * on NULL faces are not allowed, the main purpose is to clean up the
54  * mesh so that exterior loops are not represented in the data structure.
55  *
56  * __gl_meshSetWindingNumber( mesh, value, keepOnlyBoundary ) resets the
57  * winding numbers on all edges so that regions marked "inside" the
58  * polygon have a winding number of "value", and regions outside
59  * have a winding number of 0.
60  *
61  * If keepOnlyBoundary is TRUE, it also deletes all edges which do not
62  * separate an interior region from an exterior one.
63  */
64 
65 int __gl_meshTessellateMonoRegion(GLUESface* face);
66 int __gl_meshTessellateInterior(GLUESmesh* mesh);
67 void __gl_meshDiscardExterior(GLUESmesh* mesh);
68 int __gl_meshSetWindingNumber(GLUESmesh* mesh, int value, GLboolean keepOnlyBoundary);
69 
70 #endif /* __tessmono_h_ */