108 lines
3.1 KiB
C++
108 lines
3.1 KiB
C++
/*
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* Poly2Tri Copyright (c) 2009-2010, Poly2Tri Contributors
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* http://code.google.com/p/poly2tri/
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*
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* All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without modification,
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* are permitted provided that the following conditions are met:
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*
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* * Redistributions of source code must retain the above copyright notice,
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* this list of conditions and the following disclaimer.
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* * Redistributions in binary form must reproduce the above copyright notice,
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* this list of conditions and the following disclaimer in the documentation
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* and/or other materials provided with the distribution.
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* * Neither the name of Poly2Tri nor the names of its contributors may be
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* used to endorse or promote products derived from this software without specific
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* prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
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* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
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* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
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* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
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* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
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* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
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* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
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* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
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* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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*/
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#include "advancing_front.h"
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namespace p2t {
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AdvancingFront::AdvancingFront(Node& head, Node& tail)
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{
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head_ = &head;
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tail_ = &tail;
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search_node_ = &head;
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}
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Node* AdvancingFront::LocateNode(double x)
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{
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Node* node = search_node_;
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if (x < node->value) {
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while ((node = node->prev) != NULL) {
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if (x >= node->value) {
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search_node_ = node;
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return node;
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}
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}
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} else {
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while ((node = node->next) != NULL) {
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if (x < node->value) {
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search_node_ = node->prev;
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return node->prev;
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}
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}
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}
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return NULL;
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}
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Node* AdvancingFront::FindSearchNode(double x)
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{
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(void)x; // suppress compiler warnings "unused parameter 'x'"
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// TODO: implement BST index
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return search_node_;
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}
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Node* AdvancingFront::LocatePoint(const Point* point)
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{
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const double px = point->x;
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Node* node = FindSearchNode(px);
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const double nx = node->point->x;
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if (px == nx) {
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if (point != node->point) {
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// We might have two nodes with same x value for a short time
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if (point == node->prev->point) {
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node = node->prev;
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} else if (point == node->next->point) {
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node = node->next;
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} else {
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assert(0);
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}
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}
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} else if (px < nx) {
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while ((node = node->prev) != NULL) {
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if (point == node->point) {
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break;
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}
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}
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} else {
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while ((node = node->next) != NULL) {
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if (point == node->point)
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break;
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}
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}
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if(node) search_node_ = node;
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return node;
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}
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AdvancingFront::~AdvancingFront()
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{
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}
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} |