diff options
Diffstat (limited to 'src/glu/sgi/libtess/mesh.h')
| -rw-r--r-- | src/glu/sgi/libtess/mesh.h | 266 |
1 files changed, 0 insertions, 266 deletions
diff --git a/src/glu/sgi/libtess/mesh.h b/src/glu/sgi/libtess/mesh.h deleted file mode 100644 index 690c5f2f696..00000000000 --- a/src/glu/sgi/libtess/mesh.h +++ /dev/null @@ -1,266 +0,0 @@ -/* - * 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 __mesh_h_ -#define __mesh_h_ - -#include <GL/glu.h> - -typedef struct GLUmesh GLUmesh; - -typedef struct GLUvertex GLUvertex; -typedef struct GLUface GLUface; -typedef struct GLUhalfEdge GLUhalfEdge; - -typedef struct ActiveRegion ActiveRegion; /* Internal data */ - -/* The mesh structure is similar in spirit, notation, and operations - * to the "quad-edge" structure (see L. Guibas and J. Stolfi, Primitives - * for the manipulation of general subdivisions and the computation of - * Voronoi diagrams, ACM Transactions on Graphics, 4(2):74-123, April 1985). - * For a simplified description, see the course notes for CS348a, - * "Mathematical Foundations of Computer Graphics", available at the - * Stanford bookstore (and taught during the fall quarter). - * The implementation also borrows a tiny subset of the graph-based approach - * use in Mantyla's Geometric Work Bench (see M. Mantyla, An Introduction - * to Sold Modeling, Computer Science Press, Rockville, Maryland, 1988). - * - * The fundamental data structure is the "half-edge". Two half-edges - * go together to make an edge, but they point in opposite directions. - * Each half-edge has a pointer to its mate (the "symmetric" half-edge Sym), - * its origin vertex (Org), the face on its left side (Lface), and the - * adjacent half-edges in the CCW direction around the origin vertex - * (Onext) and around the left face (Lnext). There is also a "next" - * pointer for the global edge list (see below). - * - * The notation used for mesh navigation: - * Sym = the mate of a half-edge (same edge, but opposite direction) - * Onext = edge CCW around origin vertex (keep same origin) - * Dnext = edge CCW around destination vertex (keep same dest) - * Lnext = edge CCW around left face (dest becomes new origin) - * Rnext = edge CCW around right face (origin becomes new dest) - * - * "prev" means to substitute CW for CCW in the definitions above. - * - * The mesh keeps global lists of all vertices, faces, and edges, - * stored as doubly-linked circular lists with a dummy header node. - * The mesh stores pointers to these dummy headers (vHead, fHead, eHead). - * - * The circular edge list is special; since half-edges always occur - * in pairs (e and e->Sym), each half-edge stores a pointer in only - * one direction. Starting at eHead and following the e->next pointers - * will visit each *edge* once (ie. e or e->Sym, but not both). - * e->Sym stores a pointer in the opposite direction, thus it is - * always true that e->Sym->next->Sym->next == e. - * - * Each vertex has a pointer to next and previous vertices in the - * circular list, and a pointer to a half-edge with this vertex as - * the origin (NULL if this is the dummy header). There is also a - * field "data" for client data. - * - * Each face has a pointer to the next and previous faces in the - * circular list, and a pointer to a half-edge with this face as - * the left face (NULL if this is the dummy header). There is also - * a field "data" for client data. - * - * Note that what we call a "face" is really a loop; faces may consist - * of more than one loop (ie. not simply connected), but there is no - * record of this in the data structure. The mesh may consist of - * several disconnected regions, so it may not be possible to visit - * the entire mesh by starting at a half-edge and traversing the edge - * structure. - * - * The mesh does NOT support isolated vertices; a vertex is deleted along - * with its last edge. Similarly when two faces are merged, one of the - * faces is deleted (see __gl_meshDelete below). For mesh operations, - * all face (loop) and vertex pointers must not be NULL. However, once - * mesh manipulation is finished, __gl_MeshZapFace can be used to delete - * faces of the mesh, one at a time. All external faces can be "zapped" - * before the mesh is returned to the client; then a NULL face indicates - * a region which is not part of the output polygon. - */ - -struct GLUvertex { - GLUvertex *next; /* next vertex (never NULL) */ - GLUvertex *prev; /* previous vertex (never NULL) */ - GLUhalfEdge *anEdge; /* a half-edge with this origin */ - void *data; /* client's data */ - - /* Internal data (keep hidden) */ - GLdouble coords[3]; /* vertex location in 3D */ - GLdouble s, t; /* projection onto the sweep plane */ - long pqHandle; /* to allow deletion from priority queue */ -}; - -struct GLUface { - GLUface *next; /* next face (never NULL) */ - GLUface *prev; /* previous face (never NULL) */ - GLUhalfEdge *anEdge; /* a half edge with this left face */ - void *data; /* room for client's data */ - - /* Internal data (keep hidden) */ - GLUface *trail; /* "stack" for conversion to strips */ - GLboolean marked; /* flag for conversion to strips */ - GLboolean inside; /* this face is in the polygon interior */ -}; - -struct GLUhalfEdge { - GLUhalfEdge *next; /* doubly-linked list (prev==Sym->next) */ - GLUhalfEdge *Sym; /* same edge, opposite direction */ - GLUhalfEdge *Onext; /* next edge CCW around origin */ - GLUhalfEdge *Lnext; /* next edge CCW around left face */ - GLUvertex *Org; /* origin vertex (Overtex too long) */ - GLUface *Lface; /* left face */ - - /* Internal data (keep hidden) */ - ActiveRegion *activeRegion; /* a region with this upper edge (sweep.c) */ - int winding; /* change in winding number when crossing - from the right face to the left face */ -}; - -#define Rface Sym->Lface -#define Dst Sym->Org - -#define Oprev Sym->Lnext -#define Lprev Onext->Sym -#define Dprev Lnext->Sym -#define Rprev Sym->Onext -#define Dnext Rprev->Sym /* 3 pointers */ -#define Rnext Oprev->Sym /* 3 pointers */ - - -struct GLUmesh { - GLUvertex vHead; /* dummy header for vertex list */ - GLUface fHead; /* dummy header for face list */ - GLUhalfEdge eHead; /* dummy header for edge list */ - GLUhalfEdge eHeadSym; /* and its symmetric counterpart */ -}; - -/* The mesh operations below have three motivations: completeness, - * convenience, and efficiency. The basic mesh operations are MakeEdge, - * Splice, and Delete. All the other edge operations can be implemented - * in terms of these. The other operations are provided for convenience - * and/or efficiency. - * - * When a face is split or a vertex is added, they are inserted into the - * global list *before* the existing vertex or face (ie. e->Org or e->Lface). - * This makes it easier to process all vertices or faces in the global lists - * without worrying about processing the same data twice. As a convenience, - * when a face is split, the "inside" flag is copied from the old face. - * Other internal data (v->data, v->activeRegion, f->data, f->marked, - * f->trail, e->winding) is set to zero. - * - * ********************** Basic Edge Operations ************************** - * - * __gl_meshMakeEdge( mesh ) creates one edge, two vertices, and a loop. - * The loop (face) consists of the two new half-edges. - * - * __gl_meshSplice( eOrg, eDst ) is the basic operation for changing the - * mesh connectivity and topology. It changes the mesh so that - * eOrg->Onext <- OLD( eDst->Onext ) - * eDst->Onext <- OLD( eOrg->Onext ) - * where OLD(...) means the value before the meshSplice operation. - * - * This can have two effects on the vertex structure: - * - if eOrg->Org != eDst->Org, the two vertices are merged together - * - if eOrg->Org == eDst->Org, the origin is split into two vertices - * In both cases, eDst->Org is changed and eOrg->Org is untouched. - * - * Similarly (and independently) for the face structure, - * - if eOrg->Lface == eDst->Lface, one loop is split into two - * - if eOrg->Lface != eDst->Lface, two distinct loops are joined into one - * In both cases, eDst->Lface is changed and eOrg->Lface is unaffected. - * - * __gl_meshDelete( eDel ) removes the edge eDel. There are several cases: - * if (eDel->Lface != eDel->Rface), we join two loops into one; the loop - * eDel->Lface is deleted. Otherwise, we are splitting one loop into two; - * the newly created loop will contain eDel->Dst. If the deletion of eDel - * would create isolated vertices, those are deleted as well. - * - * ********************** Other Edge Operations ************************** - * - * __gl_meshAddEdgeVertex( eOrg ) creates a new edge eNew such that - * eNew == eOrg->Lnext, and eNew->Dst is a newly created vertex. - * eOrg and eNew will have the same left face. - * - * __gl_meshSplitEdge( eOrg ) splits eOrg into two edges eOrg and eNew, - * such that eNew == eOrg->Lnext. The new vertex is eOrg->Dst == eNew->Org. - * eOrg and eNew will have the same left face. - * - * __gl_meshConnect( eOrg, eDst ) creates a new edge from eOrg->Dst - * to eDst->Org, and returns the corresponding half-edge eNew. - * If eOrg->Lface == eDst->Lface, this splits one loop into two, - * and the newly created loop is eNew->Lface. Otherwise, two disjoint - * loops are merged into one, and the loop eDst->Lface is destroyed. - * - * ************************ Other Operations ***************************** - * - * __gl_meshNewMesh() creates a new mesh with no edges, no vertices, - * and no loops (what we usually call a "face"). - * - * __gl_meshUnion( mesh1, mesh2 ) forms the union of all structures in - * both meshes, and returns the new mesh (the old meshes are destroyed). - * - * __gl_meshDeleteMesh( mesh ) will free all storage for any valid mesh. - * - * __gl_meshZapFace( fZap ) destroys a face and removes it from the - * global face list. All edges of fZap will have a NULL pointer as their - * left face. Any edges which also have a NULL pointer as their right face - * are deleted entirely (along with any isolated vertices this produces). - * An entire mesh can be deleted by zapping its faces, one at a time, - * in any order. Zapped faces cannot be used in further mesh operations! - * - * __gl_meshCheckMesh( mesh ) checks a mesh for self-consistency. - */ - -GLUhalfEdge *__gl_meshMakeEdge( GLUmesh *mesh ); -int __gl_meshSplice( GLUhalfEdge *eOrg, GLUhalfEdge *eDst ); -int __gl_meshDelete( GLUhalfEdge *eDel ); - -GLUhalfEdge *__gl_meshAddEdgeVertex( GLUhalfEdge *eOrg ); -GLUhalfEdge *__gl_meshSplitEdge( GLUhalfEdge *eOrg ); -GLUhalfEdge *__gl_meshConnect( GLUhalfEdge *eOrg, GLUhalfEdge *eDst ); - -GLUmesh *__gl_meshNewMesh( void ); -GLUmesh *__gl_meshUnion( GLUmesh *mesh1, GLUmesh *mesh2 ); -void __gl_meshDeleteMesh( GLUmesh *mesh ); -void __gl_meshZapFace( GLUface *fZap ); - -#ifdef NDEBUG -#define __gl_meshCheckMesh( mesh ) -#else -void __gl_meshCheckMesh( GLUmesh *mesh ); -#endif - -#endif |