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/* Copyright (c) 1998 Silicon Graphics, Inc. */ |
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|
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#ifndef lint |
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static char SCCSid[] = "$SunId$ SGI"; |
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#endif |
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|
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/* |
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* sm_stree.c |
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*/ |
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#include "standard.h" |
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#include "sm_geom.h" |
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#include "sm_stree.h" |
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|
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/* Define 4 vertices on the sphere to create a tetrahedralization on |
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the sphere: triangles are as follows: |
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(2,1,0),(3,2,0), (1,3,0), (2,3,1) |
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*/ |
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|
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#ifdef TEST_DRIVER |
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extern FVECT Pick_point[500],Pick_v0[500],Pick_v1[500],Pick_v2[500]; |
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extern int Pick_cnt; |
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#endif |
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FVECT stDefault_base[4] = { {SQRT3_INV, SQRT3_INV, SQRT3_INV}, |
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{-SQRT3_INV, -SQRT3_INV, SQRT3_INV}, |
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{-SQRT3_INV, SQRT3_INV, -SQRT3_INV}, |
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{SQRT3_INV, -SQRT3_INV, -SQRT3_INV}}; |
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int stTri_verts[4][3] = { {2,1,0},{3,2,0},{1,3,0},{2,3,1}}; |
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int stTri_nbrs[4][3] = { {2,1,3},{0,2,3},{1,0,3},{2,0,1}}; |
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|
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stNth_base_verts(st,i,v1,v2,v3) |
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STREE *st; |
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int i; |
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FVECT v1,v2,v3; |
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{ |
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VCOPY(v1,ST_NTH_BASE(st,stTri_verts[i][0])); |
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VCOPY(v2,ST_NTH_BASE(st,stTri_verts[i][1])); |
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VCOPY(v3,ST_NTH_BASE(st,stTri_verts[i][2])); |
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} |
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|
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/* Frees the 4 quadtrees rooted at st */ |
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stClear(st) |
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STREE *st; |
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{ |
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int i; |
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|
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/* stree always has 4 children corresponding to the base tris |
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*/ |
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for (i = 0; i < 4; i++) |
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qtFree(ST_NTH_ROOT(st, i)); |
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|
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QT_CLEAR_CHILDREN(ST_ROOT(st)); |
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|
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} |
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|
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|
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STREE |
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*stInit(st,center,base) |
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STREE *st; |
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FVECT center,base[4]; |
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{ |
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|
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if(base) |
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ST_SET_BASE(st,base); |
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else |
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ST_SET_BASE(st,stDefault_base); |
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|
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ST_SET_CENTER(st,center); |
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stClear(st); |
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|
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return(st); |
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} |
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|
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|
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/* "base" defines 4 vertices on the sphere to create a tetrahedralization on |
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the sphere: triangles are as follows:(0,1,2),(0,2,3), (0,3,1), (1,3,2) |
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if base is null: does default. |
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|
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*/ |
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STREE |
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*stAlloc(st) |
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STREE *st; |
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{ |
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int i; |
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|
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if(!st) |
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st = (STREE *)malloc(sizeof(STREE)); |
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|
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ST_ROOT(st) = qtAlloc(); |
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|
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QT_CLEAR_CHILDREN(ST_ROOT(st)); |
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|
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return(st); |
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} |
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|
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|
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/* Find location of sample point in the DAG and return lowest level |
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containing triangle. "type" indicates whether the point was found |
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to be in interior to the triangle: GT_FACE, on one of its |
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edges GT_EDGE or coinciding with one of its vertices GT_VERTEX. |
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"which" specifies which vertex (0,1,2) or edge (0=v0v1, 1 = v1v2, 2 = v21) |
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*/ |
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int |
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stPoint_locate(st,npt) |
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STREE *st; |
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FVECT npt; |
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{ |
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int i,d,j,id; |
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QUADTREE *rootptr,*qtptr; |
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FVECT v1,v2,v3; |
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OBJECT os[QT_MAXSET+1],*optr; |
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FVECT p0,p1,p2; |
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|
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/* Test each of the root triangles against point id */ |
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for(i=0; i < 4; i++) |
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{ |
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rootptr = ST_NTH_ROOT_PTR(st,i); |
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stNth_base_verts(st,i,v1,v2,v3); |
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/* Return tri that p falls in */ |
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qtptr = qtRoot_point_locate(rootptr,v1,v2,v3,npt,NULL,NULL,NULL); |
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if(!qtptr || QT_IS_EMPTY(*qtptr)) |
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continue; |
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/* Get the set */ |
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optr = qtqueryset(*qtptr); |
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for (j = QT_SET_CNT(optr),optr = QT_SET_PTR(optr);j > 0; j--) |
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{ |
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/* Find the first triangle that pt falls */ |
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id = QT_SET_NEXT_ELEM(optr); |
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qtTri_from_id(id,p0,p1,p2,NULL,NULL,NULL,NULL,NULL,NULL); |
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d = point_in_stri(p0,p1,p2,npt); |
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if(d) |
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return(id); |
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} |
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} |
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return(EMPTY); |
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} |
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|
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QUADTREE |
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*stPoint_locate_cell(st,p,t0,t1,t2) |
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STREE *st; |
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FVECT p; |
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FVECT t0,t1,t2; |
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{ |
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int i,d; |
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QUADTREE *rootptr,*qtptr; |
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FVECT v0,v1,v2; |
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|
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|
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/* Test each of the root triangles against point id */ |
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for(i=0; i < 4; i++) |
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{ |
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rootptr = ST_NTH_ROOT_PTR(st,i); |
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stNth_base_verts(st,i,v0,v1,v2); |
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/* Return quadtree tri that p falls in */ |
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qtptr = qtRoot_point_locate(rootptr,v0,v1,v2,p,t0,t1,t2); |
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if(qtptr) |
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return(qtptr); |
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} /* Point not found */ |
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return(NULL); |
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} |
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|
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|
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int |
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stAdd_tri(st,id,v0,v1,v2) |
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STREE *st; |
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int id; |
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FVECT v0,v1,v2; |
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{ |
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|
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int i,found; |
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QUADTREE *rootptr; |
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FVECT t0,t1,t2; |
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|
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found = 0; |
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for(i=0; i < 4; i++) |
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{ |
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rootptr = ST_NTH_ROOT_PTR(st,i); |
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stNth_base_verts(st,i,t0,t1,t2); |
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found |= qtRoot_add_tri(rootptr,t0,t1,t2,v0,v1,v2,id,0); |
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} |
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return(found); |
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} |
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|
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int |
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stApply_to_tri_cells(st,v0,v1,v2,func,arg) |
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STREE *st; |
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FVECT v0,v1,v2; |
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int (*func)(); |
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int *arg; |
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{ |
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int i,found; |
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QUADTREE *rootptr; |
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FVECT t0,t1,t2; |
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|
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found = 0; |
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func(ST_ROOT_PTR(st),arg); |
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QT_SET_FLAG(ST_ROOT(st)); |
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for(i=0; i < 4; i++) |
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{ |
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rootptr = ST_NTH_ROOT_PTR(st,i); |
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stNth_base_verts(st,i,t0,t1,t2); |
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found |= qtApply_to_tri_cells(rootptr,v0,v1,v2,t0,t1,t2,func,arg); |
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} |
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return(found); |
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} |
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|
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|
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|
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|
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int |
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stRemove_tri(st,id,v0,v1,v2) |
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STREE *st; |
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int id; |
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FVECT v0,v1,v2; |
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{ |
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|
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int i,found; |
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QUADTREE *rootptr; |
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FVECT t0,t1,t2; |
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|
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found = 0; |
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for(i=0; i < 4; i++) |
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{ |
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rootptr = ST_NTH_ROOT_PTR(st,i); |
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stNth_base_verts(st,i,t0,t1,t2); |
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found |= qtRemove_tri(rootptr,id,v0,v1,v2,t0,t1,t2); |
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} |
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return(found); |
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} |
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|
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int |
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stVisit_tri_edges(st,t0,t1,t2,func,arg1,arg2,arg3) |
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STREE *st; |
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FVECT t0,t1,t2; |
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int (*func)(); |
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int *arg1,arg2,*arg3; |
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{ |
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int id,i,w; |
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QUADTREE *rootptr; |
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FVECT q0,q1,q2,v[3],i_pt; |
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|
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VCOPY(v[0],t0); VCOPY(v[1],t1); VCOPY(v[2],t2); |
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w = -1; |
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QT_SET_FLAG(ST_ROOT(st)); |
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for(i=0; i < 4; i++) |
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{ |
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#ifdef TEST_DRIVER |
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Pick_cnt = 0; |
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#endif |
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rootptr = ST_NTH_ROOT_PTR(st,i); |
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stNth_base_verts(st,i,q0,q1,q2); |
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/* Return quadtree tri that p falls in */ |
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if(!point_in_stri(q0,q1,q2,v[0])) |
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continue; |
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#ifdef TEST_DRIVER |
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id = qtRoot_visit_tri_edges(rootptr,q0,q1,q2,v,i_pt,&w, |
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func,arg1,arg2,arg3); |
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#else |
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id = qtRoot_visit_tri_edgesi(rootptr,q0,q1,q2,v,i_pt,&w, |
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func,arg1,arg2,arg3); |
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#endif |
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if(id == INVALID) |
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{ |
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#ifdef DEBUG |
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eputs("stVisit_tri_edges(): Unable to trace edges\n"); |
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#endif |
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return(INVALID); |
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} |
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if(id == QT_DONE) |
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return(*arg1); |
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|
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/* Crossed over to next cell: id = nbr */ |
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while(1) |
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{ |
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/* test if ray crosses plane between this quadtree triangle and |
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its neighbor- if it does then find intersection point with |
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ray and plane- this is the new origin |
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*/ |
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i = stTri_nbrs[i][id]; |
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rootptr = ST_NTH_ROOT_PTR(st,i); |
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stNth_base_verts(st,i,q0,q1,q2); |
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#ifdef TEST_DRIVER |
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id=qtRoot_visit_tri_edges(rootptr,q0,q1,q2,v,i_pt,&w, |
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func,arg1,arg2,arg3); |
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#else |
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id=qtRoot_visit_tri_edgesi(rootptr,q0,q1,q2,v,i_pt,&w, |
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func,arg1,arg2,arg3); |
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#endif |
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if(id == QT_DONE) |
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return(*arg1); |
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if(id == INVALID) |
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{ |
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#ifdef DEBUG |
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eputs("stVisit_tri_edges(): point not found\n"); |
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#endif |
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return(INVALID); |
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} |
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|
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} |
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} /* Point not found */ |
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return(INVALID); |
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} |
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|
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int |
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stTrace_ray(st,orig,dir,func,arg1,arg2) |
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STREE *st; |
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FVECT orig,dir; |
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int (*func)(); |
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int *arg1,arg2; |
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{ |
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int id,i; |
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QUADTREE *rootptr; |
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FVECT q0,q1,q2,o,n; |
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double pd,t; |
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|
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VCOPY(o,orig); |
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for(i=0; i < 4; i++) |
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{ |
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#ifdef TEST_DRIVER |
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Pick_cnt = 0; |
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#endif |
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rootptr = ST_NTH_ROOT_PTR(st,i); |
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stNth_base_verts(st,i,q0,q1,q2); |
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/* Return quadtree tri that p falls in */ |
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id= qtRoot_trace_ray(rootptr,q0,q1,q2,o,dir,func,arg1,arg2); |
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if(id == INVALID) |
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continue; |
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if(id == QT_DONE) |
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return(*arg1); |
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|
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/* Crossed over to next cell: id = nbr */ |
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while(1) |
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{ |
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/* test if ray crosses plane between this quadtree triangle and |
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its neighbor- if it does then find intersection point with |
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ray and plane- this is the new origin |
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*/ |
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if(id==0) |
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VCROSS(n,q1,q2); |
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else |
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if(id==1) |
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VCROSS(n,q2,q0); |
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else |
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VCROSS(n,q0,q1); |
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|
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/* Ray does not cross into next cell: done and tri not found*/ |
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if(!intersect_ray_plane(orig,dir,n,0.0,NULL,o)) |
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return(INVALID); |
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|
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VSUM(o,o,dir,10*FTINY); |
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i = stTri_nbrs[i][id]; |
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rootptr = ST_NTH_ROOT_PTR(st,i); |
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stNth_base_verts(st,i,q0,q1,q2); |
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id = qtRoot_trace_ray(rootptr,q0,q1,q2,o,dir,func,arg1,arg2); |
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if(id == QT_DONE) |
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return(*arg1); |
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if(id == INVALID) |
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return(INVALID); |
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|
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} |
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} /* Point not found */ |
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return(INVALID); |
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} |
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|
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|
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|
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stVisit_tri_interior(st,t0,t1,t2,func,arg1,arg2,arg3) |
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STREE *st; |
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FVECT t0,t1,t2; |
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int (*func)(); |
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int *arg1,arg2,*arg3; |
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{ |
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int i; |
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QUADTREE *rootptr; |
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FVECT q0,q1,q2; |
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|
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for(i=0; i < 4; i++) |
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{ |
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rootptr = ST_NTH_ROOT_PTR(st,i); |
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stNth_base_verts(st,i,q0,q1,q2); |
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qtVisit_tri_interior(rootptr,q0,q1,q2,t0,t1,t2,0,func,arg1,arg2,arg3); |
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} |
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} |
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|
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|
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int |
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stApply_to_tri(st,t0,t1,t2,edge_func,interior_func,arg1,arg2) |
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STREE *st; |
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FVECT t0,t1,t2; |
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int (*edge_func)(),(*interior_func)(); |
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int arg1,*arg2; |
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{ |
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int f; |
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FVECT dir; |
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|
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/* First add all of the leaf cells lying on the triangle perimeter: |
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mark all cells seen on the way |
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*/ |
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f = 0; |
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/* Visit cells along edges of the tri */ |
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|
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stVisit_tri_edges(st,t0,t1,t2,edge_func,&f,arg1,arg2); |
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|
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/* Now visit interior */ |
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if(QT_FLAG_FILL_TRI(f) || QT_FLAG_UPDATE(f)) |
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stVisit_tri_interior(st,t0,t1,t2,interior_func,&f,arg1,arg2); |
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} |
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|
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|
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|
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|
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