mutter/cogl/tesselator/mesh.c
Neil Roberts a0a06f0342 cogl/tesselator: Update to the latest code from GLU
This grabs the latest code for libtess from git Mesa. This is mostly
so that we can get the following commit which fixes a lot of compiler
warnings in Clutter:

commit 75acb896c6da758d03e86f8725d6ca0cb2c6ad82
Author: Neil Roberts <neil@linux.intel.com>
Date:   Wed Jun 30 12:41:11 2010 +0100

    glu: Fix some compiler warnings in libtess
    
    When compiled with the more aggressive compiler warnings such as
    -Wshadow and -Wempty-body the libtess code gives a lot more
    warnings. This fixes the following issues:
    
    * The 'Swap' macro tries to combine multiple statements into one and
      then consume the trailing semicolon by using if(1){/*...*/}else.
      This gives warnings because the else part ends up with an empty
      statement. It also seems a bit dangerous because if the semicolon
      were missed then it would still be valid syntax but it would just
      ignore the following statement. This patch replaces it with the more
      common idiom do { /*...*/ } while(0).
    
    * 'free' was being used as a local variable name but this shadows the
      global function. This has been renamed to 'free_handle'
    
    * TRUE and FALSE were being unconditionally defined. Although this
      isn't currently a problem it seems better to guard them with #ifndef
      because it's quite common for them to be defined in other headers.
    
    https://bugs.freedesktop.org/show_bug.cgi?id=28845
2010-06-30 16:35:33 +01:00

799 lines
22 KiB
C

/*
* 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.
**
*/
#include "gluos.h"
#include <stddef.h>
#include <assert.h>
#include "mesh.h"
#include "memalloc.h"
#ifndef TRUE
#define TRUE 1
#endif
#ifndef FALSE
#define FALSE 0
#endif
static GLUvertex *allocVertex()
{
return (GLUvertex *)memAlloc( sizeof( GLUvertex ));
}
static GLUface *allocFace()
{
return (GLUface *)memAlloc( sizeof( GLUface ));
}
/************************ Utility Routines ************************/
/* Allocate and free half-edges in pairs for efficiency.
* The *only* place that should use this fact is allocation/free.
*/
typedef struct { GLUhalfEdge e, eSym; } EdgePair;
/* MakeEdge creates a new pair of half-edges which form their own loop.
* No vertex or face structures are allocated, but these must be assigned
* before the current edge operation is completed.
*/
static GLUhalfEdge *MakeEdge( GLUhalfEdge *eNext )
{
GLUhalfEdge *e;
GLUhalfEdge *eSym;
GLUhalfEdge *ePrev;
EdgePair *pair = (EdgePair *)memAlloc( sizeof( EdgePair ));
if (pair == NULL) return NULL;
e = &pair->e;
eSym = &pair->eSym;
/* Make sure eNext points to the first edge of the edge pair */
if( eNext->Sym < eNext ) { eNext = eNext->Sym; }
/* Insert in circular doubly-linked list before eNext.
* Note that the prev pointer is stored in Sym->next.
*/
ePrev = eNext->Sym->next;
eSym->next = ePrev;
ePrev->Sym->next = e;
e->next = eNext;
eNext->Sym->next = eSym;
e->Sym = eSym;
e->Onext = e;
e->Lnext = eSym;
e->Org = NULL;
e->Lface = NULL;
e->winding = 0;
e->activeRegion = NULL;
eSym->Sym = e;
eSym->Onext = eSym;
eSym->Lnext = e;
eSym->Org = NULL;
eSym->Lface = NULL;
eSym->winding = 0;
eSym->activeRegion = NULL;
return e;
}
/* Splice( a, b ) is best described by the Guibas/Stolfi paper or the
* CS348a notes (see mesh.h). Basically it modifies the mesh so that
* a->Onext and b->Onext are exchanged. This can have various effects
* depending on whether a and b belong to different face or vertex rings.
* For more explanation see __gl_meshSplice() below.
*/
static void Splice( GLUhalfEdge *a, GLUhalfEdge *b )
{
GLUhalfEdge *aOnext = a->Onext;
GLUhalfEdge *bOnext = b->Onext;
aOnext->Sym->Lnext = b;
bOnext->Sym->Lnext = a;
a->Onext = bOnext;
b->Onext = aOnext;
}
/* MakeVertex( newVertex, eOrig, vNext ) attaches a new vertex and makes it the
* origin of all edges in the vertex loop to which eOrig belongs. "vNext" gives
* a place to insert the new vertex in the global vertex list. We insert
* the new vertex *before* vNext so that algorithms which walk the vertex
* list will not see the newly created vertices.
*/
static void MakeVertex( GLUvertex *newVertex,
GLUhalfEdge *eOrig, GLUvertex *vNext )
{
GLUhalfEdge *e;
GLUvertex *vPrev;
GLUvertex *vNew = newVertex;
assert(vNew != NULL);
/* insert in circular doubly-linked list before vNext */
vPrev = vNext->prev;
vNew->prev = vPrev;
vPrev->next = vNew;
vNew->next = vNext;
vNext->prev = vNew;
vNew->anEdge = eOrig;
vNew->data = NULL;
/* leave coords, s, t undefined */
/* fix other edges on this vertex loop */
e = eOrig;
do {
e->Org = vNew;
e = e->Onext;
} while( e != eOrig );
}
/* MakeFace( newFace, eOrig, fNext ) attaches a new face and makes it the left
* face of all edges in the face loop to which eOrig belongs. "fNext" gives
* a place to insert the new face in the global face list. We insert
* the new face *before* fNext so that algorithms which walk the face
* list will not see the newly created faces.
*/
static void MakeFace( GLUface *newFace, GLUhalfEdge *eOrig, GLUface *fNext )
{
GLUhalfEdge *e;
GLUface *fPrev;
GLUface *fNew = newFace;
assert(fNew != NULL);
/* insert in circular doubly-linked list before fNext */
fPrev = fNext->prev;
fNew->prev = fPrev;
fPrev->next = fNew;
fNew->next = fNext;
fNext->prev = fNew;
fNew->anEdge = eOrig;
fNew->data = NULL;
fNew->trail = NULL;
fNew->marked = FALSE;
/* The new face is marked "inside" if the old one was. This is a
* convenience for the common case where a face has been split in two.
*/
fNew->inside = fNext->inside;
/* fix other edges on this face loop */
e = eOrig;
do {
e->Lface = fNew;
e = e->Lnext;
} while( e != eOrig );
}
/* KillEdge( eDel ) destroys an edge (the half-edges eDel and eDel->Sym),
* and removes from the global edge list.
*/
static void KillEdge( GLUhalfEdge *eDel )
{
GLUhalfEdge *ePrev, *eNext;
/* Half-edges are allocated in pairs, see EdgePair above */
if( eDel->Sym < eDel ) { eDel = eDel->Sym; }
/* delete from circular doubly-linked list */
eNext = eDel->next;
ePrev = eDel->Sym->next;
eNext->Sym->next = ePrev;
ePrev->Sym->next = eNext;
memFree( eDel );
}
/* KillVertex( vDel ) destroys a vertex and removes it from the global
* vertex list. It updates the vertex loop to point to a given new vertex.
*/
static void KillVertex( GLUvertex *vDel, GLUvertex *newOrg )
{
GLUhalfEdge *e, *eStart = vDel->anEdge;
GLUvertex *vPrev, *vNext;
/* change the origin of all affected edges */
e = eStart;
do {
e->Org = newOrg;
e = e->Onext;
} while( e != eStart );
/* delete from circular doubly-linked list */
vPrev = vDel->prev;
vNext = vDel->next;
vNext->prev = vPrev;
vPrev->next = vNext;
memFree( vDel );
}
/* KillFace( fDel ) destroys a face and removes it from the global face
* list. It updates the face loop to point to a given new face.
*/
static void KillFace( GLUface *fDel, GLUface *newLface )
{
GLUhalfEdge *e, *eStart = fDel->anEdge;
GLUface *fPrev, *fNext;
/* change the left face of all affected edges */
e = eStart;
do {
e->Lface = newLface;
e = e->Lnext;
} while( e != eStart );
/* delete from circular doubly-linked list */
fPrev = fDel->prev;
fNext = fDel->next;
fNext->prev = fPrev;
fPrev->next = fNext;
memFree( fDel );
}
/****************** Basic Edge Operations **********************/
/* __gl_meshMakeEdge creates one edge, two vertices, and a loop (face).
* The loop consists of the two new half-edges.
*/
GLUhalfEdge *__gl_meshMakeEdge( GLUmesh *mesh )
{
GLUvertex *newVertex1= allocVertex();
GLUvertex *newVertex2= allocVertex();
GLUface *newFace= allocFace();
GLUhalfEdge *e;
/* if any one is null then all get freed */
if (newVertex1 == NULL || newVertex2 == NULL || newFace == NULL) {
if (newVertex1 != NULL) memFree(newVertex1);
if (newVertex2 != NULL) memFree(newVertex2);
if (newFace != NULL) memFree(newFace);
return NULL;
}
e = MakeEdge( &mesh->eHead );
if (e == NULL) {
memFree(newVertex1);
memFree(newVertex2);
memFree(newFace);
return NULL;
}
MakeVertex( newVertex1, e, &mesh->vHead );
MakeVertex( newVertex2, e->Sym, &mesh->vHead );
MakeFace( newFace, e, &mesh->fHead );
return e;
}
/* __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.
*
* Some special cases:
* If eDst == eOrg, the operation has no effect.
* If eDst == eOrg->Lnext, the new face will have a single edge.
* If eDst == eOrg->Lprev, the old face will have a single edge.
* If eDst == eOrg->Onext, the new vertex will have a single edge.
* If eDst == eOrg->Oprev, the old vertex will have a single edge.
*/
int __gl_meshSplice( GLUhalfEdge *eOrg, GLUhalfEdge *eDst )
{
int joiningLoops = FALSE;
int joiningVertices = FALSE;
if( eOrg == eDst ) return 1;
if( eDst->Org != eOrg->Org ) {
/* We are merging two disjoint vertices -- destroy eDst->Org */
joiningVertices = TRUE;
KillVertex( eDst->Org, eOrg->Org );
}
if( eDst->Lface != eOrg->Lface ) {
/* We are connecting two disjoint loops -- destroy eDst->Lface */
joiningLoops = TRUE;
KillFace( eDst->Lface, eOrg->Lface );
}
/* Change the edge structure */
Splice( eDst, eOrg );
if( ! joiningVertices ) {
GLUvertex *newVertex= allocVertex();
if (newVertex == NULL) return 0;
/* We split one vertex into two -- the new vertex is eDst->Org.
* Make sure the old vertex points to a valid half-edge.
*/
MakeVertex( newVertex, eDst, eOrg->Org );
eOrg->Org->anEdge = eOrg;
}
if( ! joiningLoops ) {
GLUface *newFace= allocFace();
if (newFace == NULL) return 0;
/* We split one loop into two -- the new loop is eDst->Lface.
* Make sure the old face points to a valid half-edge.
*/
MakeFace( newFace, eDst, eOrg->Lface );
eOrg->Lface->anEdge = eOrg;
}
return 1;
}
/* __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.
*
* This function could be implemented as two calls to __gl_meshSplice
* plus a few calls to memFree, but this would allocate and delete
* unnecessary vertices and faces.
*/
int __gl_meshDelete( GLUhalfEdge *eDel )
{
GLUhalfEdge *eDelSym = eDel->Sym;
int joiningLoops = FALSE;
/* First step: disconnect the origin vertex eDel->Org. We make all
* changes to get a consistent mesh in this "intermediate" state.
*/
if( eDel->Lface != eDel->Rface ) {
/* We are joining two loops into one -- remove the left face */
joiningLoops = TRUE;
KillFace( eDel->Lface, eDel->Rface );
}
if( eDel->Onext == eDel ) {
KillVertex( eDel->Org, NULL );
} else {
/* Make sure that eDel->Org and eDel->Rface point to valid half-edges */
eDel->Rface->anEdge = eDel->Oprev;
eDel->Org->anEdge = eDel->Onext;
Splice( eDel, eDel->Oprev );
if( ! joiningLoops ) {
GLUface *newFace= allocFace();
if (newFace == NULL) return 0;
/* We are splitting one loop into two -- create a new loop for eDel. */
MakeFace( newFace, eDel, eDel->Lface );
}
}
/* Claim: the mesh is now in a consistent state, except that eDel->Org
* may have been deleted. Now we disconnect eDel->Dst.
*/
if( eDelSym->Onext == eDelSym ) {
KillVertex( eDelSym->Org, NULL );
KillFace( eDelSym->Lface, NULL );
} else {
/* Make sure that eDel->Dst and eDel->Lface point to valid half-edges */
eDel->Lface->anEdge = eDelSym->Oprev;
eDelSym->Org->anEdge = eDelSym->Onext;
Splice( eDelSym, eDelSym->Oprev );
}
/* Any isolated vertices or faces have already been freed. */
KillEdge( eDel );
return 1;
}
/******************** Other Edge Operations **********************/
/* All these routines can be implemented with the basic edge
* operations above. They are provided for convenience and efficiency.
*/
/* __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.
*/
GLUhalfEdge *__gl_meshAddEdgeVertex( GLUhalfEdge *eOrg )
{
GLUhalfEdge *eNewSym;
GLUhalfEdge *eNew = MakeEdge( eOrg );
if (eNew == NULL) return NULL;
eNewSym = eNew->Sym;
/* Connect the new edge appropriately */
Splice( eNew, eOrg->Lnext );
/* Set the vertex and face information */
eNew->Org = eOrg->Dst;
{
GLUvertex *newVertex= allocVertex();
if (newVertex == NULL) return NULL;
MakeVertex( newVertex, eNewSym, eNew->Org );
}
eNew->Lface = eNewSym->Lface = eOrg->Lface;
return eNew;
}
/* __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.
*/
GLUhalfEdge *__gl_meshSplitEdge( GLUhalfEdge *eOrg )
{
GLUhalfEdge *eNew;
GLUhalfEdge *tempHalfEdge= __gl_meshAddEdgeVertex( eOrg );
if (tempHalfEdge == NULL) return NULL;
eNew = tempHalfEdge->Sym;
/* Disconnect eOrg from eOrg->Dst and connect it to eNew->Org */
Splice( eOrg->Sym, eOrg->Sym->Oprev );
Splice( eOrg->Sym, eNew );
/* Set the vertex and face information */
eOrg->Dst = eNew->Org;
eNew->Dst->anEdge = eNew->Sym; /* may have pointed to eOrg->Sym */
eNew->Rface = eOrg->Rface;
eNew->winding = eOrg->winding; /* copy old winding information */
eNew->Sym->winding = eOrg->Sym->winding;
return eNew;
}
/* __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.
*
* If (eOrg == eDst), the new face will have only two edges.
* If (eOrg->Lnext == eDst), the old face is reduced to a single edge.
* If (eOrg->Lnext->Lnext == eDst), the old face is reduced to two edges.
*/
GLUhalfEdge *__gl_meshConnect( GLUhalfEdge *eOrg, GLUhalfEdge *eDst )
{
GLUhalfEdge *eNewSym;
int joiningLoops = FALSE;
GLUhalfEdge *eNew = MakeEdge( eOrg );
if (eNew == NULL) return NULL;
eNewSym = eNew->Sym;
if( eDst->Lface != eOrg->Lface ) {
/* We are connecting two disjoint loops -- destroy eDst->Lface */
joiningLoops = TRUE;
KillFace( eDst->Lface, eOrg->Lface );
}
/* Connect the new edge appropriately */
Splice( eNew, eOrg->Lnext );
Splice( eNewSym, eDst );
/* Set the vertex and face information */
eNew->Org = eOrg->Dst;
eNewSym->Org = eDst->Org;
eNew->Lface = eNewSym->Lface = eOrg->Lface;
/* Make sure the old face points to a valid half-edge */
eOrg->Lface->anEdge = eNewSym;
if( ! joiningLoops ) {
GLUface *newFace= allocFace();
if (newFace == NULL) return NULL;
/* We split one loop into two -- the new loop is eNew->Lface */
MakeFace( newFace, eNew, eOrg->Lface );
}
return eNew;
}
/******************** Other Operations **********************/
/* __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!
*/
void __gl_meshZapFace( GLUface *fZap )
{
GLUhalfEdge *eStart = fZap->anEdge;
GLUhalfEdge *e, *eNext, *eSym;
GLUface *fPrev, *fNext;
/* walk around face, deleting edges whose right face is also NULL */
eNext = eStart->Lnext;
do {
e = eNext;
eNext = e->Lnext;
e->Lface = NULL;
if( e->Rface == NULL ) {
/* delete the edge -- see __gl_MeshDelete above */
if( e->Onext == e ) {
KillVertex( e->Org, NULL );
} else {
/* Make sure that e->Org points to a valid half-edge */
e->Org->anEdge = e->Onext;
Splice( e, e->Oprev );
}
eSym = e->Sym;
if( eSym->Onext == eSym ) {
KillVertex( eSym->Org, NULL );
} else {
/* Make sure that eSym->Org points to a valid half-edge */
eSym->Org->anEdge = eSym->Onext;
Splice( eSym, eSym->Oprev );
}
KillEdge( e );
}
} while( e != eStart );
/* delete from circular doubly-linked list */
fPrev = fZap->prev;
fNext = fZap->next;
fNext->prev = fPrev;
fPrev->next = fNext;
memFree( fZap );
}
/* __gl_meshNewMesh() creates a new mesh with no edges, no vertices,
* and no loops (what we usually call a "face").
*/
GLUmesh *__gl_meshNewMesh( void )
{
GLUvertex *v;
GLUface *f;
GLUhalfEdge *e;
GLUhalfEdge *eSym;
GLUmesh *mesh = (GLUmesh *)memAlloc( sizeof( GLUmesh ));
if (mesh == NULL) {
return NULL;
}
v = &mesh->vHead;
f = &mesh->fHead;
e = &mesh->eHead;
eSym = &mesh->eHeadSym;
v->next = v->prev = v;
v->anEdge = NULL;
v->data = NULL;
f->next = f->prev = f;
f->anEdge = NULL;
f->data = NULL;
f->trail = NULL;
f->marked = FALSE;
f->inside = FALSE;
e->next = e;
e->Sym = eSym;
e->Onext = NULL;
e->Lnext = NULL;
e->Org = NULL;
e->Lface = NULL;
e->winding = 0;
e->activeRegion = NULL;
eSym->next = eSym;
eSym->Sym = e;
eSym->Onext = NULL;
eSym->Lnext = NULL;
eSym->Org = NULL;
eSym->Lface = NULL;
eSym->winding = 0;
eSym->activeRegion = NULL;
return mesh;
}
/* __gl_meshUnion( mesh1, mesh2 ) forms the union of all structures in
* both meshes, and returns the new mesh (the old meshes are destroyed).
*/
GLUmesh *__gl_meshUnion( GLUmesh *mesh1, GLUmesh *mesh2 )
{
GLUface *f1 = &mesh1->fHead;
GLUvertex *v1 = &mesh1->vHead;
GLUhalfEdge *e1 = &mesh1->eHead;
GLUface *f2 = &mesh2->fHead;
GLUvertex *v2 = &mesh2->vHead;
GLUhalfEdge *e2 = &mesh2->eHead;
/* Add the faces, vertices, and edges of mesh2 to those of mesh1 */
if( f2->next != f2 ) {
f1->prev->next = f2->next;
f2->next->prev = f1->prev;
f2->prev->next = f1;
f1->prev = f2->prev;
}
if( v2->next != v2 ) {
v1->prev->next = v2->next;
v2->next->prev = v1->prev;
v2->prev->next = v1;
v1->prev = v2->prev;
}
if( e2->next != e2 ) {
e1->Sym->next->Sym->next = e2->next;
e2->next->Sym->next = e1->Sym->next;
e2->Sym->next->Sym->next = e1;
e1->Sym->next = e2->Sym->next;
}
memFree( mesh2 );
return mesh1;
}
#ifdef DELETE_BY_ZAPPING
/* __gl_meshDeleteMesh( mesh ) will free all storage for any valid mesh.
*/
void __gl_meshDeleteMesh( GLUmesh *mesh )
{
GLUface *fHead = &mesh->fHead;
while( fHead->next != fHead ) {
__gl_meshZapFace( fHead->next );
}
assert( mesh->vHead.next == &mesh->vHead );
memFree( mesh );
}
#else
/* __gl_meshDeleteMesh( mesh ) will free all storage for any valid mesh.
*/
void __gl_meshDeleteMesh( GLUmesh *mesh )
{
GLUface *f, *fNext;
GLUvertex *v, *vNext;
GLUhalfEdge *e, *eNext;
for( f = mesh->fHead.next; f != &mesh->fHead; f = fNext ) {
fNext = f->next;
memFree( f );
}
for( v = mesh->vHead.next; v != &mesh->vHead; v = vNext ) {
vNext = v->next;
memFree( v );
}
for( e = mesh->eHead.next; e != &mesh->eHead; e = eNext ) {
/* One call frees both e and e->Sym (see EdgePair above) */
eNext = e->next;
memFree( e );
}
memFree( mesh );
}
#endif
#ifndef NDEBUG
/* __gl_meshCheckMesh( mesh ) checks a mesh for self-consistency.
*/
void __gl_meshCheckMesh( GLUmesh *mesh )
{
GLUface *fHead = &mesh->fHead;
GLUvertex *vHead = &mesh->vHead;
GLUhalfEdge *eHead = &mesh->eHead;
GLUface *f, *fPrev;
GLUvertex *v, *vPrev;
GLUhalfEdge *e, *ePrev;
fPrev = fHead;
for( fPrev = fHead ; (f = fPrev->next) != fHead; fPrev = f) {
assert( f->prev == fPrev );
e = f->anEdge;
do {
assert( e->Sym != e );
assert( e->Sym->Sym == e );
assert( e->Lnext->Onext->Sym == e );
assert( e->Onext->Sym->Lnext == e );
assert( e->Lface == f );
e = e->Lnext;
} while( e != f->anEdge );
}
assert( f->prev == fPrev && f->anEdge == NULL && f->data == NULL );
vPrev = vHead;
for( vPrev = vHead ; (v = vPrev->next) != vHead; vPrev = v) {
assert( v->prev == vPrev );
e = v->anEdge;
do {
assert( e->Sym != e );
assert( e->Sym->Sym == e );
assert( e->Lnext->Onext->Sym == e );
assert( e->Onext->Sym->Lnext == e );
assert( e->Org == v );
e = e->Onext;
} while( e != v->anEdge );
}
assert( v->prev == vPrev && v->anEdge == NULL && v->data == NULL );
ePrev = eHead;
for( ePrev = eHead ; (e = ePrev->next) != eHead; ePrev = e) {
assert( e->Sym->next == ePrev->Sym );
assert( e->Sym != e );
assert( e->Sym->Sym == e );
assert( e->Org != NULL );
assert( e->Dst != NULL );
assert( e->Lnext->Onext->Sym == e );
assert( e->Onext->Sym->Lnext == e );
}
assert( e->Sym->next == ePrev->Sym
&& e->Sym == &mesh->eHeadSym
&& e->Sym->Sym == e
&& e->Org == NULL && e->Dst == NULL
&& e->Lface == NULL && e->Rface == NULL );
}
#endif