organicmaps/libtess2
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Delaunay cleanup: Added bucket allocator, more robust trigonometry, coding style

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This commit is contained in:
Marius Kintel 2015-01-13 12:12:01 -05:00
parent 50dc8f0566
commit 59b61f2c13
3 changed files with 40 additions and 23 deletions
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11
Source/geom.c
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@ -264,11 +264,16 @@ void tesedgeIntersect( TESSvertex *o1, TESSvertex *d1,
/*
Calculate the angle between v1-v2 and v1-v0
*/
TESSreal calcAngle(TESSvertex *v0, TESSvertex *v1, TESSvertex *v2) {
TESSreal calcAngle( TESSvertex *v0, TESSvertex *v1, TESSvertex *v2 )
{
TESSreal a[2] = { v2->s - v1->s, v2->t - v1->t };
TESSreal b[2] = { v0->s - v1->s, v0->t - v1->t };
return acosf((a[0] * b[0] + a[1] * b[1]) /
(sqrt(a[0] * a[0] + a[1] * a[1]) * sqrt(b[0] * b[0] + b[1] * b[1])));
TESSreal num = a[0] * b[0] + a[1] * b[1];
TESSreal den = sqrt( a[0] * a[0] + a[1] * a[1] ) * sqrt( b[0] * b[0] + b[1] * b[1] );
if ( den > 0.0 ) num /= den;
if ( num < -1.0 ) num = -1.0;
if ( num > 1.0 ) num = 1.0;
return acos( num );
}
/*

6
Source/mesh.c
View file

@ -750,8 +750,6 @@ int tessMeshMergeConvexFaces( TESSmesh *mesh, int maxVertsPerFace )
return 1;
}
#include <stdio.h>
void tessMeshFlipEdge( TESSmesh *mesh, TESShalfEdge *edge )
{
assert(EdgeIsInternal(edge));
@ -779,8 +777,8 @@ void tessMeshFlipEdge( TESSmesh *mesh, TESShalfEdge *edge )
b0->Onext = a1->Sym;
a2->Onext = b0;
b2->Onext = a0;
b1->Onext = a2->Sym;
a1->Onext = b2->Sym;
b1->Onext = a2->Sym;
a1->Onext = b2->Sym;
a0->Lnext = a2;
a2->Lnext = b1;

46
Source/tess.c
View file

@ -385,41 +385,53 @@ int tessMeshTessellateInterior( TESSmesh *mesh )
}
typedef struct EdgeStackNode EdgeStackNode;
typedef struct EdgeStack EdgeStack;
struct EdgeStackNode {
TESShalfEdge *edge;
struct EdgeStackNode *next;
EdgeStackNode *next;
};
struct EdgeStack {
struct EdgeStackNode *top;
EdgeStackNode *top;
struct BucketAlloc *nodeBucket;
};
void stackInit(struct EdgeStack *stack)
int stackInit( EdgeStack *stack, TESSalloc *alloc )
{
stack->top = NULL;
stack->top = NULL;
stack->nodeBucket = createBucketAlloc( alloc, "CDT nodes", sizeof(EdgeStackNode), 512 );
return stack->nodeBucket != NULL;
}
int stackEmpty(struct EdgeStack *stack)
void stackDelete( EdgeStack *stack )
{
deleteBucketAlloc( stack->nodeBucket );
}
int stackEmpty( EdgeStack *stack )
{
return stack->top == NULL;
}
void stackPush(struct EdgeStack *stack, TESShalfEdge *e)
void stackPush( EdgeStack *stack, TESShalfEdge *e )
{
struct EdgeStackNode *node = malloc(sizeof(struct EdgeStackNode));
EdgeStackNode *node = (EdgeStackNode *)bucketAlloc( stack->nodeBucket );
if ( ! node ) return;
node->edge = e;
node->next = stack->top;
stack->top = node;
}
TESShalfEdge *stackPop(struct EdgeStack *stack)
TESShalfEdge *stackPop( EdgeStack *stack )
{
TESShalfEdge *e = NULL;
struct EdgeStackNode *node = stack->top;
TESShalfEdge *e = NULL;
EdgeStackNode *node = stack->top;
if (node) {
stack->top = node->next;
e = node->edge;
free(node);
bucketFree( stack->nodeBucket, node );
}
return e;
}
@ -428,7 +440,7 @@ TESShalfEdge *stackPop(struct EdgeStack *stack)
Starting with a valid triangulation, uses the Edge Flip algorithm to
refine the triangulation into a Constrained Delaunay Triangulation.
*/
int tessMeshRefineDelaunay( TESSmesh *mesh )
int tessMeshRefineDelaunay( TESSmesh *mesh, TESSalloc *alloc )
{
/* At this point, we have a valid, but not optimal, triangulation.
We refine the triangulation using the Edge Flip algorithm */
@ -439,8 +451,8 @@ int tessMeshRefineDelaunay( TESSmesh *mesh )
3) insert all dual edges into a queue
*/
TESSface *f;
struct EdgeStack stack;
stackInit(&stack);
EdgeStack stack;
stackInit(&stack, alloc);
TESShalfEdge *e;
TESShalfEdge *edges[4];
for( f = mesh->fHead.next; f != &mesh->fHead; f = f->next ) {
@ -453,7 +465,7 @@ int tessMeshRefineDelaunay( TESSmesh *mesh )
} while (e != f->anEdge);
}
}
// Pop stack until we find a reversed edge
// Flip the reversed edge, and insert any of the four opposite edges
// which are internal and not already in the stack (!marked)
@ -475,6 +487,8 @@ int tessMeshRefineDelaunay( TESSmesh *mesh )
}
}
}
stackDelete(&stack);
return 1;
}
@ -1020,7 +1034,7 @@ int tessTesselate( TESStesselator *tess, int windingRule, int elementType,
} else {
rc = tessMeshTessellateInterior( mesh );
if (elementType == TESS_CONSTRAINED_DELAUNAY_TRIANGLES) {
rc = tessMeshRefineDelaunay( mesh );
rc = tessMeshRefineDelaunay( mesh, &tess->alloc );
elementType = TESS_POLYGONS;
polySize = 3;
}