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/*

** Author: Eric Veach, July 1994.

**

*/


#ifndef __tessmono_h_

#define __tessmono_h_


/* __gl_meshTessellateMonoRegion( face ) tessellates a monotone region

 * (what else would it do??)  The region must consist of a single

 * loop of half-edges (see mesh.h) oriented CCW.  "Monotone" in this

 * case means that any vertical line intersects the interior of the

 * region in a single interval.

 *

 * Tessellation consists of adding interior edges (actually pairs of

 * half-edges), to split the region into non-overlapping triangles.

 *

 * __gl_meshTessellateInterior( mesh ) tessellates each region of

 * the mesh which is marked "inside" the polygon.  Each such region

 * must be monotone.

 *

 * __gl_meshDiscardExterior( mesh ) zaps (ie. sets to NULL) all faces

 * which are not marked "inside" the polygon.  Since further mesh operations

 * on NULL faces are not allowed, the main purpose is to clean up the

 * mesh so that exterior loops are not represented in the data structure.

 *

 * __gl_meshSetWindingNumber( mesh, value, keepOnlyBoundary ) resets the

 * winding numbers on all edges so that regions marked "inside" the

 * polygon have a winding number of "value", and regions outside

 * have a winding number of 0.

 *

 * If keepOnlyBoundary is TRUE, it also deletes all edges which do not

 * separate an interior region from an exterior one.

 */


int __gl_meshTessellateMonoRegion(GLUface *face);

int __gl_meshTessellateInterior(GLUmesh *mesh);

void __gl_meshDiscardExterior(GLUmesh *mesh);

int __gl_meshSetWindingNumber(GLUmesh *mesh, int value, GLboolean keepOnlyBoundary);


#endif