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authormarha <marha@users.sourceforge.net>2012-09-03 09:54:39 +0200
committermarha <marha@users.sourceforge.net>2012-09-03 09:54:39 +0200
commitb86e8562b1ddca2a8bc29f22a79451a041bf5293 (patch)
tree60fead0638fce6922b4043767fa991ff1f0e3488 /mesalib/src/glu/sgi/libnurbs/nurbtess/partitionY.cc
parent53192e17e55aa9ed3e3721bf4fdcb2b01a595202 (diff)
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mesa xkeyboard-config git update 3 sep 2012
Diffstat (limited to 'mesalib/src/glu/sgi/libnurbs/nurbtess/partitionY.cc')
-rw-r--r--mesalib/src/glu/sgi/libnurbs/nurbtess/partitionY.cc836
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diff --git a/mesalib/src/glu/sgi/libnurbs/nurbtess/partitionY.cc b/mesalib/src/glu/sgi/libnurbs/nurbtess/partitionY.cc
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-/*
-** License Applicability. Except to the extent portions of this file are
-** made subject to an alternative license as permitted in the SGI Free
-** Software License B, Version 1.1 (the "License"), the contents of this
-** file are subject only to the provisions of the License. You may not use
-** this file except in compliance with the License. You may obtain a copy
-** of the License at Silicon Graphics, Inc., attn: Legal Services, 1600
-** Amphitheatre Parkway, Mountain View, CA 94043-1351, or at:
-**
-** http://oss.sgi.com/projects/FreeB
-**
-** Note that, as provided in the License, the Software is distributed on an
-** "AS IS" basis, with ALL EXPRESS AND IMPLIED WARRANTIES AND CONDITIONS
-** DISCLAIMED, INCLUDING, WITHOUT LIMITATION, ANY IMPLIED WARRANTIES AND
-** CONDITIONS OF MERCHANTABILITY, SATISFACTORY QUALITY, FITNESS FOR A
-** PARTICULAR PURPOSE, AND NON-INFRINGEMENT.
-**
-** Original Code. The Original Code is: OpenGL Sample Implementation,
-** Version 1.2.1, released January 26, 2000, developed by Silicon Graphics,
-** Inc. The Original Code is Copyright (c) 1991-2000 Silicon Graphics, Inc.
-** Copyright in any portions created by third parties is as indicated
-** elsewhere herein. All Rights Reserved.
-**
-** Additional Notice Provisions: The application programming interfaces
-** established by SGI in conjunction with the Original Code are The
-** OpenGL(R) Graphics System: A Specification (Version 1.2.1), released
-** April 1, 1999; The OpenGL(R) Graphics System Utility Library (Version
-** 1.3), released November 4, 1998; and OpenGL(R) Graphics with the X
-** Window System(R) (Version 1.3), released October 19, 1998. This software
-** was created using the OpenGL(R) version 1.2.1 Sample Implementation
-** published by SGI, but has not been independently verified as being
-** compliant with the OpenGL(R) version 1.2.1 Specification.
-**
-*/
-/*
-*/
-
-#include <stdlib.h>
-#include <stdio.h>
-#include <time.h>
-
-#include "zlassert.h"
-#include "partitionY.h"
-#include "searchTree.h"
-#include "quicksort.h"
-#include "polyUtil.h"
-
-
-#define max(a,b) ((a>b)? a:b)
-#define min(a,b) ((a>b)? b:a)
-
-
-/*retrurn
- *-1: if A < B (Ya<Yb) || (Ya==Yb)
- * 0: if A == B
- * 1: if A>B
- */
-static Int compVertInY(Real A[2], Real B[2])
-{
- if( (A[1] < B[1]) || (A[1]==B[1] && A[0]<B[0]))
- return -1;
- else if
- ( A[1] == B[1] && A[0] == B[0]) return 0;
- else
- return 1;
-}
-
-/*v is a vertex: the head of en edge,
- *e is an edge,
- *return 1 if e is below v: assume v1 and v2 are the two endpoints of e:
- * v1<= v, v2<=v.
- */
-Int isBelow(directedLine *v, directedLine *e)
-{
- Real* vert = v->head();
- if( compVertInY(e->head(), vert) != 1
- && compVertInY(e->tail(), vert) != 1
- )
- return 1;
- else
- return 0;
-}
-
-/*v is a vertex: the head of en edge,
- *e is an edge,
- *return 1 if e is below v: assume v1 and v2 are the two endpoints of e:
- * v1>= v, v2>=v.
- */
-Int isAbove(directedLine *v, directedLine *e)
-{
- Real* vert = v->head();
- if( compVertInY(e->head(), vert) != -1
- && compVertInY(e->tail(), vert) != -1
- )
- return 1;
- else
- return 0;
-}
-
-Int isCusp(directedLine *v)
-{
- Real *A=v->getPrev()->head();
- Real *B=v->head();
- Real *C=v->tail();
- if(A[1] < B[1] && B[1] < C[1])
- return 0;
- else if(A[1] > B[1] && B[1] > C[1])
- return 0;
- else if(A[1] < B[1] && C[1] < B[1])
- return 1;
- else if(A[1] > B[1] && C[1] > B[1])
- return 1;
-
- if((isAbove(v, v) && isAbove(v, v->getPrev())) ||
- (isBelow(v, v) && isBelow(v, v->getPrev())))
- return 1;
- else
- return 0;
-}
-
-/*crossproduct is strictly less than 0*/
-Int isReflex(directedLine *v)
-{
- Real* A = v->getPrev()->head();
- Real* B = v->head();
- Real* C = v->tail();
- Real Bx,By, Cx, Cy;
- Bx = B[0] - A[0];
- By = B[1] - A[1];
- Cx = C[0] - A[0];
- Cy = C[1] - A[1];
-
- if(Bx*Cy - Cx*By < 0) return 1;
- else return 0;
-}
-
- /*return
- *0: not-cusp
- *1: interior cusp
- *2: exterior cusp
- */
-Int cuspType(directedLine *v)
-{
- if(! isCusp(v)) return 0;
- else if(isReflex(v)) return 1;
- else
- return 2;
-}
-
-sweepRange* sweepRangeMake(directedLine* left, Int leftType,
- directedLine* right, Int rightType)
-{
- sweepRange* ret = (sweepRange*)malloc(sizeof(sweepRange));
- assert(ret);
- ret->left = left;
- ret->leftType = leftType;
- ret->right = right;
- ret->rightType = rightType;
- return ret;
-}
-
-void sweepRangeDelete(sweepRange* range)
-{
- free(range);
-}
-
-Int sweepRangeEqual(sweepRange* src1, sweepRange* src2)
-{
- Int leftEqual;
- Int rightEqual;
-
-
- /*The case when both are vertices should not happen*/
- assert(! (src1->leftType == 0 && src2->leftType == 0));
- if(src1->leftType == 0 && src2->leftType == 1){
- if(src1->left == src2->left ||
- src1->left->getPrev() == src2->left
- )
- leftEqual = 1;
- else
- leftEqual = 0;
- }
- else if(src1->leftType == 1 && src2->leftType == 1){
- if(src1->left == src2->left)
- leftEqual = 1;
- else
- leftEqual = 0;
- }
- else /*src1->leftType == 1 && src2->leftType == 0*/{
- if(src1->left == src2->left ||
- src1->left == src2->left->getPrev()
- )
- leftEqual = 1;
- else
- leftEqual = 0;
- }
-
- /*the same thing for right*/
- /*The case when both are vertices should not happen*/
- assert(! (src1->rightType == 0 && src2->rightType == 0));
- if(src1->rightType == 0 && src2->rightType == 1){
- if(src1->right == src2->right ||
- src1->right->getPrev() == src2->right
- )
- rightEqual = 1;
- else
- rightEqual = 0;
- }
- else if(src1->rightType == 1 && src2->rightType == 1){
- if(src1->right == src2->right)
- rightEqual = 1;
- else
- rightEqual = 0;
- }
- else /*src1->rightType == 1 && src2->rightType == 0*/{
- if(src1->right == src2->right ||
- src1->right == src2->right->getPrev()
- )
- rightEqual = 1;
- else
- rightEqual = 0;
- }
-
- return (leftEqual == 1 || rightEqual == 1);
-}
-
-/*given (x_1, y_1) and (x_2, y_2), and y
- *return x such that (x,y) is on the line
- */
-inline/*static*/ Real intersectHoriz(Real x1, Real y1, Real x2, Real y2, Real y)
-{
- return ((y2==y1)? (x1+x2)*Real(0.5) : x1 + ((y-y1)/(y2-y1)) * (x2-x1));
-/*
- if(y2 == y1) return (x1+x2)*0.5;
- else return x1 + ((y-y1)/(y2-y1)) * (x2-x1);
-*/
-}
-
-/*compare two edges of a polygon.
- *edge A < edge B if there is a horizontal line so that the intersection
- *with A is to the left of the intersection with B.
- *This function is used in sweepY for the dynamic search tree insertion to
- *order the edges.
- * Implementation: (x_1,y_1) and (x_2, y_2)
- */
-static Int compEdges(directedLine *e1, directedLine *e2)
-{
- Real* head1 = e1->head();
- Real* tail1 = e1->tail();
- Real* head2 = e2->head();
- Real* tail2 = e2->tail();
-/*
- Real h10 = head1[0];
- Real h11 = head1[1];
- Real t10 = tail1[0];
- Real t11 = tail1[1];
- Real h20 = head2[0];
- Real h21 = head2[1];
- Real t20 = tail2[0];
- Real t21 = tail2[1];
-*/
- Real e1_Ymax, e1_Ymin, e2_Ymax, e2_Ymin;
-/*
- if(h11>t11) {
- e1_Ymax= h11;
- e1_Ymin= t11;
- }
- else{
- e1_Ymax = t11;
- e1_Ymin = h11;
- }
-
- if(h21>t21) {
- e2_Ymax= h21;
- e2_Ymin= t21;
- }
- else{
- e2_Ymax = t21;
- e2_Ymin = h21;
- }
-*/
-
- if(head1[1]>tail1[1]) {
- e1_Ymax= head1[1];
- e1_Ymin= tail1[1];
- }
- else{
- e1_Ymax = tail1[1];
- e1_Ymin = head1[1];
- }
-
- if(head2[1]>tail2[1]) {
- e2_Ymax= head2[1];
- e2_Ymin= tail2[1];
- }
- else{
- e2_Ymax = tail2[1];
- e2_Ymin = head2[1];
- }
-
-
- /*Real e1_Ymax = max(head1[1], tail1[1]);*/ /*max(e1->head()[1], e1->tail()[1]);*/
- /*Real e1_Ymin = min(head1[1], tail1[1]);*/ /*min(e1->head()[1], e1->tail()[1]);*/
- /*Real e2_Ymax = max(head2[1], tail2[1]);*/ /*max(e2->head()[1], e2->tail()[1]);*/
- /*Real e2_Ymin = min(head2[1], tail2[1]);*/ /*min(e2->head()[1], e2->tail()[1]);*/
-
- Real Ymax = min(e1_Ymax, e2_Ymax);
- Real Ymin = max(e1_Ymin, e2_Ymin);
-
- Real y = Real(0.5)*(Ymax + Ymin);
-
-/* Real x1 = intersectHoriz(e1->head()[0], e1->head()[1], e1->tail()[0], e1->tail()[1], y);
- Real x2 = intersectHoriz(e2->head()[0], e2->head()[1], e2->tail()[0], e2->tail()[1], y);
-*/
-/*
- Real x1 = intersectHoriz(h10, h11, t10, t11, y);
- Real x2 = intersectHoriz(h20, h21, t20, t21, y);
-*/
- Real x1 = intersectHoriz(head1[0], head1[1], tail1[0], tail1[1], y);
- Real x2 = intersectHoriz(head2[0], head2[1], tail2[0], tail2[1], y);
-
- if(x1<= x2) return -1;
- else return 1;
-}
-
-/*used by sort precedures
- */
-static Int compInY(directedLine* v1, directedLine* v2)
-{
- return v1->compInY(v2);
-}
-
-void findDiagonals(Int total_num_edges, directedLine** sortedVertices, sweepRange** ranges, Int& num_diagonals, directedLine** diagonal_vertices)
-{
- Int i,j,k;
-
- k=0;
-
- for(i=0; i<total_num_edges; i++)
- {
- directedLine* vert =sortedVertices[i];
- directedLine* thisEdge = vert;
- directedLine* prevEdge = vert->getPrev();
-/*
-printf("find i=%i\n", i);
-printf("the vertex is\n");
-vert->printSingle();
-*/
- if(isBelow(vert, thisEdge) && isBelow(vert, prevEdge) && compEdges(prevEdge, thisEdge)<0)
- {
- /*this is an upward interior cusp*/
- diagonal_vertices[k++] = vert;
-
- for(j=i+1; j<total_num_edges; j++)
- if(sweepRangeEqual(ranges[i], ranges[j]))
- {
- diagonal_vertices[k++] = sortedVertices[j];
- break;
- }
- assert(j<total_num_edges);
-
-
- }
- else if(isAbove(vert, thisEdge) && isAbove(vert, prevEdge) && compEdges(prevEdge, thisEdge)>0)
- {
- /*this is an downward interior cusp*/
- diagonal_vertices[k++] = vert;
- for(j=i-1; j>=0; j--)
- if(sweepRangeEqual(ranges[i], ranges[j]))
- {
- diagonal_vertices[k++] = sortedVertices[j];
- break;
- }
-/* printf("j=%i\n", j);*/
- assert(j>=0);
-
-
-
- }
- }
- num_diagonals = k/2;
-}
-
-/*get rid of repeated diagonlas so that each diagonal appears only once in the array
- */
-Int deleteRepeatDiagonals(Int num_diagonals, directedLine** diagonal_vertices, directedLine** new_vertices)
-{
- Int i,k;
- Int j,l;
- Int index;
- index=0;
- for(i=0,k=0; i<num_diagonals; i++, k+=2)
- {
- Int isRepeated=0;
- /*check the diagonla (diagonal_vertice[k], diagonal_vertices[k+1])
- *is repeated or not
- */
- for(j=0,l=0; j<index; j++, l+=2)
- {
- if(
- (diagonal_vertices[k] == new_vertices[l] &&
- diagonal_vertices[k+1] == new_vertices[l+1]
- )
- ||
- (
- diagonal_vertices[k] == new_vertices[l+1] &&
- diagonal_vertices[k+1] == new_vertices[l]
- )
- )
- {
- isRepeated=1;
- break;
- }
- }
- if(! isRepeated)
- {
- new_vertices[index+index] = diagonal_vertices[k];
- new_vertices[index+index+1] = diagonal_vertices[k+1];
- index++;
- }
- }
- return index;
-}
-
-/*for debug only*/
-directedLine** DBGfindDiagonals(directedLine *polygons, Int& num_diagonals)
-{
- Int total_num_edges = 0;
- directedLine** array = polygons->toArrayAllPolygons(total_num_edges);
- quicksort( (void**)array, 0, total_num_edges-1, (Int (*)(void*, void*)) compInY);
- sweepRange** ranges = (sweepRange**) malloc(sizeof(sweepRange*) * total_num_edges);
- assert(ranges);
-
- sweepY(total_num_edges, array, ranges);
-
- directedLine** diagonal_vertices = (directedLine**) malloc(sizeof(directedLine*) * total_num_edges);
- assert(diagonal_vertices);
- findDiagonals(total_num_edges, array, ranges, num_diagonals, diagonal_vertices);
-
- num_diagonals=deleteRepeatDiagonals(num_diagonals, diagonal_vertices, diagonal_vertices);
- return diagonal_vertices;
-
-}
-
-
-/*partition into Y-monotone polygons*/
-directedLine* partitionY(directedLine *polygons, sampledLine **retSampledLines)
-{
- Int total_num_edges = 0;
- directedLine** array = polygons->toArrayAllPolygons(total_num_edges);
-
- quicksort( (void**)array, 0, total_num_edges-1, (Int (*)(void*, void*)) compInY);
-
- sweepRange** ranges = (sweepRange**) malloc(sizeof(sweepRange*) * (total_num_edges));
- assert(ranges);
-
-
-
- sweepY(total_num_edges, array, ranges);
-
-
-
- /*the diagonal vertices are stored as:
- *v0-v1: 1st diagonal
- *v2-v3: 2nd diagonal
- *v5-v5: 3rd diagonal
- *...
- */
-
-
- Int num_diagonals;
- /*number diagonals is < total_num_edges*total_num_edges*/
- directedLine** diagonal_vertices = (directedLine**) malloc(sizeof(directedLine*) * total_num_edges*2/*total_num_edges*/);
- assert(diagonal_vertices);
-
-
-
- findDiagonals(total_num_edges, array, ranges, num_diagonals, diagonal_vertices);
-
-
-
- directedLine* ret_polygons = polygons;
- sampledLine* newSampledLines = NULL;
- Int i,k;
-
-num_diagonals=deleteRepeatDiagonals(num_diagonals, diagonal_vertices, diagonal_vertices);
-
-
-
- Int *removedDiagonals=(Int*)malloc(sizeof(Int) * num_diagonals);
- for(i=0; i<num_diagonals; i++)
- removedDiagonals[i] = 0;
-
-
-
-
-
- for(i=0,k=0; i<num_diagonals; i++,k+=2)
- {
-
-
- directedLine* v1=diagonal_vertices[k];
- directedLine* v2=diagonal_vertices[k+1];
- directedLine* ret_p1;
- directedLine* ret_p2;
-
- /*we ahve to determine whether v1 and v2 belong to the same polygon before
- *their structure are modified by connectDiagonal().
- */
-/*
- directedLine *root1 = v1->findRoot();
- directedLine *root2 = v2->findRoot();
- assert(root1);
- assert(root2);
-*/
-
-directedLine* root1 = v1->rootLinkFindRoot();
-directedLine* root2 = v2->rootLinkFindRoot();
-
- if(root1 != root2)
- {
-
- removedDiagonals[i] = 1;
- sampledLine* generatedLine;
-
-
-
- v1->connectDiagonal(v1,v2, &ret_p1, &ret_p2, &generatedLine, ret_polygons);
-
-
-
- newSampledLines = generatedLine->insert(newSampledLines);
-/*
- ret_polygons = ret_polygons->cutoffPolygon(root1);
-
- ret_polygons = ret_polygons->cutoffPolygon(root2);
- ret_polygons = ret_p1->insertPolygon(ret_polygons);
-root1->rootLinkSet(ret_p1);
-root2->rootLinkSet(ret_p1);
-ret_p1->rootLinkSet(NULL);
-ret_p2->rootLinkSet(ret_p1);
-*/
- ret_polygons = ret_polygons->cutoffPolygon(root2);
-
-
-
-root2->rootLinkSet(root1);
-ret_p1->rootLinkSet(root1);
-ret_p2->rootLinkSet(root1);
-
- /*now that we have connected the diagonal v1 and v2,
- *we have to check those unprocessed diagonals which
- *have v1 or v2 as an end point. Notice that the head of v1
- *has the same coodinates as the head of v2->prev, and the head of
- *v2 has the same coordinate as the head of v1->prev.
- *Suppose these is a diagonal (v1, x). If (v1,x) is still a valid
- *diagonal, then x should be on the left hand side of the directed line: *v1->prev->head -- v1->head -- v1->tail. Otherwise, (v1,x) should be
- *replaced by (v2->prev, x), that is, x is on the left of
- * v2->prev->prev->head, v2->prev->head, v2->prev->tail.
- */
- Int ii, kk;
- for(ii=0, kk=0; ii<num_diagonals; ii++, kk+=2)
- if( removedDiagonals[ii]==0)
- {
- directedLine* d1=diagonal_vertices[kk];
- directedLine* d2=diagonal_vertices[kk+1];
- /*check d1, and replace diagonal_vertices[kk] if necessary*/
- if(d1 == v1) {
- /*check if d2 is to left of v1->prev->head:v1->head:v1->tail*/
- if(! pointLeft2Lines(v1->getPrev()->head(),
- v1->head(), v1->tail(), d2->head()))
- {
-/*
- assert(pointLeft2Lines(v2->getPrev()->getPrev()->head(),
- v2->getPrev()->head(),
- v2->getPrev()->tail(), d2->head()));
-*/
- diagonal_vertices[kk] = v2->getPrev();
- }
- }
- if(d1 == v2) {
- /*check if d2 is to left of v2->prev->head:v2->head:v2->tail*/
- if(! pointLeft2Lines(v2->getPrev()->head(),
- v2->head(), v2->tail(), d2->head()))
- {
-/*
- assert(pointLeft2Lines(v1->getPrev()->getPrev()->head(),
- v1->getPrev()->head(),
- v1->getPrev()->tail(), d2->head()));
-*/
- diagonal_vertices[kk] = v1->getPrev();
- }
- }
- /*check d2 and replace diagonal_vertices[k+1] if necessary*/
- if(d2 == v1) {
- /*check if d1 is to left of v1->prev->head:v1->head:v1->tail*/
- if(! pointLeft2Lines(v1->getPrev()->head(),
- v1->head(), v1->tail(), d1->head()))
- {
-/* assert(pointLeft2Lines(v2->getPrev()->getPrev()->head(),
- v2->getPrev()->head(),
- v2->getPrev()->tail(), d1->head()));
-*/
- diagonal_vertices[kk+1] = v2->getPrev();
- }
- }
- if(d2 == v2) {
- /*check if d1 is to left of v2->prev->head:v2->head:v2->tail*/
- if(! pointLeft2Lines(v2->getPrev()->head(),
- v2->head(), v2->tail(), d1->head()))
- {
-/* assert(pointLeft2Lines(v1->getPrev()->getPrev()->head(),
- v1->getPrev()->head(),
- v1->getPrev()->tail(), d1->head()));
-*/
- diagonal_vertices[kk+1] = v1->getPrev();
- }
- }
- }
-}/*end if (root1 not equal to root 2)*/
-}
-
- /*second pass, now all diagoals should belong to the same polygon*/
-
-
-
- for(i=0,k=0; i<num_diagonals; i++, k += 2)
- if(removedDiagonals[i] == 0)
- {
-
-
- directedLine* v1=diagonal_vertices[k];
- directedLine* v2=diagonal_vertices[k+1];
-
-
-
- directedLine* ret_p1;
- directedLine* ret_p2;
-
- /*we ahve to determine whether v1 and v2 belong to the same polygon before
- *their structure are modified by connectDiagonal().
- */
- directedLine *root1 = v1->findRoot();
-/*
- directedLine *root2 = v2->findRoot();
-
-
-
- assert(root1);
- assert(root2);
- assert(root1 == root2);
- */
- sampledLine* generatedLine;
-
-
-
- v1->connectDiagonal(v1,v2, &ret_p1, &ret_p2, &generatedLine, ret_polygons);
- newSampledLines = generatedLine->insert(newSampledLines);
-
- ret_polygons = ret_polygons->cutoffPolygon(root1);
-
- ret_polygons = ret_p1->insertPolygon(ret_polygons);
-
- ret_polygons = ret_p2->insertPolygon(ret_polygons);
-
-
-
- for(Int j=i+1; j<num_diagonals; j++)
- {
- if(removedDiagonals[j] ==0)
- {
-
- directedLine* temp1=diagonal_vertices[2*j];
- directedLine* temp2=diagonal_vertices[2*j+1];
- if(temp1==v1 || temp1==v2 || temp2==v1 || temp2==v2)
- if(! temp1->samePolygon(temp1, temp2))
- {
- /*if temp1 and temp2 are in different polygons,
- *then one of them must be v1 or v2.
- */
-
-
-
- assert(temp1==v1 || temp1 == v2 || temp2==v1 || temp2 ==v2);
- if(temp1==v1)
- {
- diagonal_vertices[2*j] = v2->getPrev();
- }
- if(temp2==v1)
- {
- diagonal_vertices[2*j+1] = v2->getPrev();
- }
- if(temp1==v2)
- {
- diagonal_vertices[2*j] = v1->getPrev();
- }
- if(temp2==v2)
- {
- diagonal_vertices[2*j+1] = v1->getPrev();
- }
- }
- }
- }
-
- }
-
- /*clean up spaces*/
- free(array);
- free(ranges);
- free(diagonal_vertices);
- free(removedDiagonals);
-
- *retSampledLines = newSampledLines;
- return ret_polygons;
-}
-
-/*given a set of simple polygons where the interior
- *is decided by left-hand principle,
- *return a range (sight) for each vertex. This is called
- *Trapezoidalization.
- */
-void sweepY(Int nVertices, directedLine** sortedVertices, sweepRange** ret_ranges)
-{
- Int i;
- /*for each vertex in the sorted list, update the binary search tree.
- *and store the range information for each vertex.
- */
- treeNode* searchTree = NULL;
- for(i=0; i<nVertices;i++)
- {
-
- directedLine* vert = sortedVertices[i];
-
- directedLine* thisEdge = vert;
- directedLine* prevEdge = vert->getPrev();
-
- if(isBelow(vert, thisEdge) && isAbove(vert, prevEdge))
- {
-
- /*case 1: this < v < prev
- *the polygon is going down at v, the interior is to
- *the right hand side.
- * find the edge to the right of thisEdge for right range.
- * delete thisEdge
- * insert prevEdge
- */
- treeNode* thisNode = TreeNodeFind(searchTree, thisEdge, ( Int (*) (void *, void *))compEdges);
- assert(thisNode);
-
- treeNode* succ = TreeNodeSuccessor(thisNode);
- assert(succ);
- searchTree = TreeNodeDeleteSingleNode(searchTree, thisNode);
- searchTree = TreeNodeInsert(searchTree, TreeNodeMake(prevEdge), ( Int (*) (void *, void *))compEdges);
-
-
- ret_ranges[i] = sweepRangeMake(vert, 0, (directedLine*) (succ->key), 1);
-
- }
- else if(isAbove(vert, thisEdge) && isBelow(vert, prevEdge))
- {
-
- /*case 2: this > v > prev
- *the polygon is going up at v, the interior is to
- *the left hand side.
- * find the edge to the left of thisEdge for left range.
- * delete prevEdge
- * insert thisEdge
- */
- treeNode* prevNode = TreeNodeFind(searchTree, prevEdge, ( Int (*) (void *, void *))compEdges);
- assert(prevNode);
- treeNode* pred = TreeNodePredecessor(prevNode);
- searchTree = TreeNodeDeleteSingleNode(searchTree, prevNode);
- searchTree = TreeNodeInsert(searchTree, TreeNodeMake(thisEdge), ( Int (*) (void *, void *))compEdges);
- ret_ranges[i] = sweepRangeMake((directedLine*)(pred->key), 1, vert, 0);
- }
- else if(isAbove(vert, thisEdge) && isAbove(vert, prevEdge))
- {
-
- /*case 3: insert both edges*/
- treeNode* thisNode = TreeNodeMake(thisEdge);
- treeNode* prevNode = TreeNodeMake(prevEdge);
- searchTree = TreeNodeInsert(searchTree, thisNode, ( Int (*) (void *, void *))compEdges);
- searchTree = TreeNodeInsert(searchTree, prevNode, ( Int (*) (void *, void *))compEdges);
- if(compEdges(thisEdge, prevEdge)<0) /*interior cusp*/
- {
-
- treeNode* leftEdge = TreeNodePredecessor(thisNode);
- treeNode* rightEdge = TreeNodeSuccessor(prevNode);
- ret_ranges[i] = sweepRangeMake( (directedLine*) leftEdge->key, 1,
- (directedLine*) rightEdge->key, 1
- );
- }
- else /*exterior cusp*/
- {
-
- ret_ranges[i] = sweepRangeMake( prevEdge, 1, thisEdge, 1);
- }
- }
- else if(isBelow(vert, thisEdge) && isBelow(vert, prevEdge))
- {
-
- /*case 4: delete both edges*/
- treeNode* thisNode = TreeNodeFind(searchTree, thisEdge, ( Int (*) (void *, void *))compEdges);
- treeNode* prevNode = TreeNodeFind(searchTree, prevEdge, ( Int (*) (void *, void *))compEdges);
- if(compEdges(thisEdge, prevEdge)>0) /*interior cusp*/
- {
- treeNode* leftEdge = TreeNodePredecessor(prevNode);
- treeNode* rightEdge = TreeNodeSuccessor(thisNode);
- ret_ranges[i] = sweepRangeMake( (directedLine*) leftEdge->key, 1,
- (directedLine*) rightEdge->key, 1
- );
- }
- else /*exterior cusp*/
- {
- ret_ranges[i] = sweepRangeMake( thisEdge, 1, prevEdge, 1);
- }
- searchTree = TreeNodeDeleteSingleNode(searchTree, thisNode);
- searchTree = TreeNodeDeleteSingleNode(searchTree, prevNode);
- }
- else
- {
- fprintf(stderr,"error in partitionY.C, invalid case\n");
- printf("vert is\n");
- vert->printSingle();
- printf("thisEdge is\n");
- thisEdge->printSingle();
- printf("prevEdge is\n");
- prevEdge->printSingle();
-
- exit(1);
- }
- }
-
- /*finaly clean up space: delete the search tree*/
- TreeNodeDeleteWholeTree(searchTree);
-}