windows-server-2003/multimedia/opengl/glu/libtess/tessmono.h

#ifndef __tessmono_h_
#define __tessmono_h_

/*
** Copyright 1994, Silicon Graphics, Inc.
** All Rights Reserved.
** 
** This is UNPUBLISHED PROPRIETARY SOURCE CODE of Silicon Graphics, Inc.;
** the contents of this file may not be disclosed to third parties, copied or
** duplicated in any form, in whole or in part, without the prior written
** permission of Silicon Graphics, Inc.
** 
** RESTRICTED RIGHTS LEGEND:
** Use, duplication or disclosure by the Government is subject to restrictions
** as set forth in subdivision (c)(1)(ii) of the Rights in Technical Data
** and Computer Software clause at DFARS 252.227-7013, and/or in similar or
** successor clauses in the FAR, DOD or NASA FAR Supplement. Unpublished -
** rights reserved under the Copyright Laws of the United States.
**
** Author: Eric Veach, July 1994.
*/


/* __gl_meshTesselateMonoRegion( face ) tesselates 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.  
 *
 * Tesselation consists of adding interior edges (actually pairs of
 * half-edges), to split the region into non-overlapping triangles.
 *
 * __gl_meshTesselateInterior( mesh ) tesselates 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.
 */

void __gl_meshTesselateMonoRegion( GLUface *face );
void __gl_meshTesselateInterior( GLUmesh *mesh );
void __gl_meshDiscardExterior( GLUmesh *mesh );
void __gl_meshSetWindingNumber( GLUmesh *mesh, int value,
			        GLboolean keepOnlyBoundary );

#endif