Home | History | Annotate | Download | only in libtess
      1 /*
      2 ** License Applicability. Except to the extent portions of this file are
      3 ** made subject to an alternative license as permitted in the SGI Free
      4 ** Software License B, Version 1.1 (the "License"), the contents of this
      5 ** file are subject only to the provisions of the License. You may not use
      6 ** this file except in compliance with the License. You may obtain a copy
      7 ** of the License at Silicon Graphics, Inc., attn: Legal Services, 1600
      8 ** Amphitheatre Parkway, Mountain View, CA 94043-1351, or at:
      9 **
     10 ** http://oss.sgi.com/projects/FreeB
     11 **
     12 ** Note that, as provided in the License, the Software is distributed on an
     13 ** "AS IS" basis, with ALL EXPRESS AND IMPLIED WARRANTIES AND CONDITIONS
     14 ** DISCLAIMED, INCLUDING, WITHOUT LIMITATION, ANY IMPLIED WARRANTIES AND
     15 ** CONDITIONS OF MERCHANTABILITY, SATISFACTORY QUALITY, FITNESS FOR A
     16 ** PARTICULAR PURPOSE, AND NON-INFRINGEMENT.
     17 **
     18 ** Original Code. The Original Code is: OpenGL Sample Implementation,
     19 ** Version 1.2.1, released January 26, 2000, developed by Silicon Graphics,
     20 ** Inc. The Original Code is Copyright (c) 1991-2000 Silicon Graphics, Inc.
     21 ** Copyright in any portions created by third parties is as indicated
     22 ** elsewhere herein. All Rights Reserved.
     23 **
     24 ** Additional Notice Provisions: The application programming interfaces
     25 ** established by SGI in conjunction with the Original Code are The
     26 ** OpenGL(R) Graphics System: A Specification (Version 1.2.1), released
     27 ** April 1, 1999; The OpenGL(R) Graphics System Utility Library (Version
     28 ** 1.3), released November 4, 1998; and OpenGL(R) Graphics with the X
     29 ** Window System(R) (Version 1.3), released October 19, 1998. This software
     30 ** was created using the OpenGL(R) version 1.2.1 Sample Implementation
     31 ** published by SGI, but has not been independently verified as being
     32 ** compliant with the OpenGL(R) version 1.2.1 Specification.
     33 **
     34 */
     35 /*
     36 ** Author: Eric Veach, July 1994.
     37 **
     38 ** $Date$ $Revision$
     39 ** $Header: //depot/main/gfx/lib/glu/libtess/tess.h#6 $
     40 */
     41 
     42 #ifndef __tess_h_
     43 #define __tess_h_
     44 
     45 #include <sk_glu.h>
     46 #include <setjmp.h>
     47 #include "mesh.h"
     48 #include "dict.h"
     49 #include "priorityq.h"
     50 
     51 /* The begin/end calls must be properly nested.  We keep track of
     52  * the current state to enforce the ordering.
     53  */
     54 enum TessState { T_DORMANT, T_IN_POLYGON, T_IN_CONTOUR };
     55 
     56 /* We cache vertex data for single-contour polygons so that we can
     57  * try a quick-and-dirty decomposition first.
     58  */
     59 #define TESS_MAX_CACHE	100
     60 
     61 typedef struct CachedVertex {
     62   GLdouble	coords[3];
     63   void		*data;
     64 } CachedVertex;
     65 
     66 struct GLUtesselator {
     67 
     68   /*** state needed for collecting the input data ***/
     69 
     70   enum TessState state;		/* what begin/end calls have we seen? */
     71 
     72   GLUhalfEdge	*lastEdge;	/* lastEdge->Org is the most recent vertex */
     73   GLUmesh	*mesh;		/* stores the input contours, and eventually
     74                                    the tessellation itself */
     75 
     76   void		(GLAPIENTRY *callError)( GLenum errnum );
     77 
     78   /*** state needed for projecting onto the sweep plane ***/
     79 
     80   GLdouble	normal[3];	/* user-specified normal (if provided) */
     81   GLdouble	sUnit[3];	/* unit vector in s-direction (debugging) */
     82   GLdouble	tUnit[3];	/* unit vector in t-direction (debugging) */
     83 
     84   /*** state needed for the line sweep ***/
     85 
     86   GLdouble	relTolerance;	/* tolerance for merging features */
     87   GLenum	windingRule;	/* rule for determining polygon interior */
     88   GLboolean	fatalError;	/* fatal error: needed combine callback */
     89 
     90   Dict		*dict;		/* edge dictionary for sweep line */
     91   PriorityQ	*pq;		/* priority queue of vertex events */
     92   GLUvertex	*event;		/* current sweep event being processed */
     93 
     94   void		(GLAPIENTRY *callCombine)( GLdouble coords[3], void *data[4],
     95 			        GLfloat weight[4], void **outData );
     96 
     97   /*** state needed for rendering callbacks (see render.c) ***/
     98 
     99   GLboolean	flagBoundary;	/* mark boundary edges (use EdgeFlag) */
    100   GLboolean	boundaryOnly;	/* Extract contours, not triangles */
    101   GLUface	*lonelyTriList;
    102     /* list of triangles which could not be rendered as strips or fans */
    103 
    104   void		(GLAPIENTRY *callBegin)( GLenum type );
    105   void		(GLAPIENTRY *callEdgeFlag)( GLboolean boundaryEdge );
    106   void		(GLAPIENTRY *callVertex)( void *data );
    107   void		(GLAPIENTRY *callEnd)( void );
    108   void		(GLAPIENTRY *callMesh)( GLUmesh *mesh );
    109 
    110 
    111   /*** state needed to cache single-contour polygons for renderCache() */
    112 
    113   GLboolean	emptyCache;		/* empty cache on next vertex() call */
    114   int		cacheCount;		/* number of cached vertices */
    115   CachedVertex	cache[TESS_MAX_CACHE];	/* the vertex data */
    116 
    117   /*** rendering callbacks that also pass polygon data  ***/
    118   void		(GLAPIENTRY *callBeginData)( GLenum type, void *polygonData );
    119   void		(GLAPIENTRY *callEdgeFlagData)( GLboolean boundaryEdge,
    120 				     void *polygonData );
    121   void		(GLAPIENTRY *callVertexData)( void *data, void *polygonData );
    122   void		(GLAPIENTRY *callEndData)( void *polygonData );
    123   void		(GLAPIENTRY *callErrorData)( GLenum errnum, void *polygonData );
    124   void		(GLAPIENTRY *callCombineData)( GLdouble coords[3], void *data[4],
    125 				    GLfloat weight[4], void **outData,
    126 				    void *polygonData );
    127 
    128   jmp_buf env;			/* place to jump to when memAllocs fail */
    129 
    130   void *polygonData;		/* client data for current polygon */
    131 };
    132 
    133 void GLAPIENTRY __gl_noBeginData( GLenum type, void *polygonData );
    134 void GLAPIENTRY __gl_noEdgeFlagData( GLboolean boundaryEdge, void *polygonData );
    135 void GLAPIENTRY __gl_noVertexData( void *data, void *polygonData );
    136 void GLAPIENTRY __gl_noEndData( void *polygonData );
    137 void GLAPIENTRY __gl_noErrorData( GLenum errnum, void *polygonData );
    138 void GLAPIENTRY __gl_noCombineData( GLdouble coords[3], void *data[4],
    139 			 GLfloat weight[4], void **outData,
    140 			 void *polygonData );
    141 
    142 #define CALL_BEGIN_OR_BEGIN_DATA(a) \
    143    if (tess->callBeginData != &__gl_noBeginData) \
    144       (*tess->callBeginData)((a),tess->polygonData); \
    145    else (*tess->callBegin)((a));
    146 
    147 #define CALL_VERTEX_OR_VERTEX_DATA(a) \
    148    if (tess->callVertexData != &__gl_noVertexData) \
    149       (*tess->callVertexData)((a),tess->polygonData); \
    150    else (*tess->callVertex)((a));
    151 
    152 #define CALL_EDGE_FLAG_OR_EDGE_FLAG_DATA(a) \
    153    if (tess->callEdgeFlagData != &__gl_noEdgeFlagData) \
    154       (*tess->callEdgeFlagData)((a),tess->polygonData); \
    155    else (*tess->callEdgeFlag)((a));
    156 
    157 #define CALL_END_OR_END_DATA() \
    158    if (tess->callEndData != &__gl_noEndData) \
    159       (*tess->callEndData)(tess->polygonData); \
    160    else (*tess->callEnd)();
    161 
    162 #define CALL_COMBINE_OR_COMBINE_DATA(a,b,c,d) \
    163    if (tess->callCombineData != &__gl_noCombineData) \
    164       (*tess->callCombineData)((a),(b),(c),(d),tess->polygonData); \
    165    else (*tess->callCombine)((a),(b),(c),(d));
    166 
    167 #define CALL_ERROR_OR_ERROR_DATA(a) \
    168    if (tess->callErrorData != &__gl_noErrorData) \
    169       (*tess->callErrorData)((a),tess->polygonData); \
    170    else (*tess->callError)((a));
    171 
    172 #endif
    173