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