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/*
* SGI FREE SOFTWARE LICENSE B (Version 2.0, Sept. 18, 2008)
* Copyright (C) 1991-2000 Silicon Graphics, Inc. All Rights Reserved.
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice including the dates of first publication and
* either this permission notice or a reference to
* http://oss.sgi.com/projects/FreeB/
* shall be included in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
* OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* SILICON GRAPHICS, INC. BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
* WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF
* OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*
* Except as contained in this notice, the name of Silicon Graphics, Inc.
* shall not be used in advertising or otherwise to promote the sale, use or
* other dealings in this Software without prior written authorization from
* Silicon Graphics, Inc.
*/
/*
** Author: Eric Veach, July 1994.
**
*/
#ifndef __tess_h_
#define __tess_h_
#include <GL/glu.h>
#include <setjmp.h>
#include "mesh.h"
#include "dict.h"
#include "priorityq.h"
/* The begin/end calls must be properly nested. We keep track of
* the current state to enforce the ordering.
*/
enum TessState { T_DORMANT, T_IN_POLYGON, T_IN_CONTOUR };
/* We cache vertex data for single-contour polygons so that we can
* try a quick-and-dirty decomposition first.
*/
#define TESS_MAX_CACHE 100
typedef struct CachedVertex {
GLdouble coords[3];
void *data;
} CachedVertex;
struct GLUtesselator {
/*** state needed for collecting the input data ***/
enum TessState state; /* what begin/end calls have we seen? */
GLUhalfEdge *lastEdge; /* lastEdge->Org is the most recent vertex */
GLUmesh *mesh; /* stores the input contours, and eventually
the tessellation itself */
void (GLAPIENTRY *callError)( GLenum errnum );
/*** state needed for projecting onto the sweep plane ***/
GLdouble normal[3]; /* user-specified normal (if provided) */
GLdouble sUnit[3]; /* unit vector in s-direction (debugging) */
GLdouble tUnit[3]; /* unit vector in t-direction (debugging) */
/*** state needed for the line sweep ***/
GLdouble relTolerance; /* tolerance for merging features */
GLenum windingRule; /* rule for determining polygon interior */
GLboolean fatalError; /* fatal error: needed combine callback */
Dict *dict; /* edge dictionary for sweep line */
PriorityQ *pq; /* priority queue of vertex events */
GLUvertex *event; /* current sweep event being processed */
void (GLAPIENTRY *callCombine)( GLdouble coords[3], void *data[4],
GLfloat weight[4], void **outData );
/*** state needed for rendering callbacks (see render.c) ***/
GLboolean flagBoundary; /* mark boundary edges (use EdgeFlag) */
GLboolean boundaryOnly; /* Extract contours, not triangles */
GLUface *lonelyTriList;
/* list of triangles which could not be rendered as strips or fans */
void (GLAPIENTRY *callBegin)( GLenum type );
void (GLAPIENTRY *callEdgeFlag)( GLboolean boundaryEdge );
void (GLAPIENTRY *callVertex)( void *data );
void (GLAPIENTRY *callEnd)( void );
void (GLAPIENTRY *callMesh)( GLUmesh *mesh );
/*** state needed to cache single-contour polygons for renderCache() */
GLboolean emptyCache; /* empty cache on next vertex() call */
int cacheCount; /* number of cached vertices */
CachedVertex cache[TESS_MAX_CACHE]; /* the vertex data */
/*** rendering callbacks that also pass polygon data ***/
void (GLAPIENTRY *callBeginData)( GLenum type, void *polygonData );
void (GLAPIENTRY *callEdgeFlagData)( GLboolean boundaryEdge,
void *polygonData );
void (GLAPIENTRY *callVertexData)( void *data, void *polygonData );
void (GLAPIENTRY *callEndData)( void *polygonData );
void (GLAPIENTRY *callErrorData)( GLenum errnum, void *polygonData );
void (GLAPIENTRY *callCombineData)( GLdouble coords[3], void *data[4],
GLfloat weight[4], void **outData,
void *polygonData );
jmp_buf env; /* place to jump to when memAllocs fail */
void *polygonData; /* client data for current polygon */
};
void GLAPIENTRY __gl_noBeginData( GLenum type, void *polygonData );
void GLAPIENTRY __gl_noEdgeFlagData( GLboolean boundaryEdge, void *polygonData );
void GLAPIENTRY __gl_noVertexData( void *data, void *polygonData );
void GLAPIENTRY __gl_noEndData( void *polygonData );
void GLAPIENTRY __gl_noErrorData( GLenum errnum, void *polygonData );
void GLAPIENTRY __gl_noCombineData( GLdouble coords[3], void *data[4],
GLfloat weight[4], void **outData,
void *polygonData );
#define CALL_BEGIN_OR_BEGIN_DATA(a) \
if (tess->callBeginData != &__gl_noBeginData) \
(*tess->callBeginData)((a),tess->polygonData); \
else (*tess->callBegin)((a));
#define CALL_VERTEX_OR_VERTEX_DATA(a) \
if (tess->callVertexData != &__gl_noVertexData) \
(*tess->callVertexData)((a),tess->polygonData); \
else (*tess->callVertex)((a));
#define CALL_EDGE_FLAG_OR_EDGE_FLAG_DATA(a) \
if (tess->callEdgeFlagData != &__gl_noEdgeFlagData) \
(*tess->callEdgeFlagData)((a),tess->polygonData); \
else (*tess->callEdgeFlag)((a));
#define CALL_END_OR_END_DATA() \
if (tess->callEndData != &__gl_noEndData) \
(*tess->callEndData)(tess->polygonData); \
else (*tess->callEnd)();
#define CALL_COMBINE_OR_COMBINE_DATA(a,b,c,d) \
if (tess->callCombineData != &__gl_noCombineData) \
(*tess->callCombineData)((a),(b),(c),(d),tess->polygonData); \
else (*tess->callCombine)((a),(b),(c),(d));
#define CALL_ERROR_OR_ERROR_DATA(a) \
if (tess->callErrorData != &__gl_noErrorData) \
(*tess->callErrorData)((a),tess->polygonData); \
else (*tess->callError)((a));
#endif
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