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/*
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* This file is a part of the C port of the Poly2Tri library
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* Porting to C done by (c) Barak Itkin <lightningismyname@gmail.com>
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* http://code.google.com/p/poly2tri-c/
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*
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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 <math.h>
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#include "sweep.h"
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#include "sweep_context.h"
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#include "advancing_front.h"
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#include "../common/utils.h"
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#include "../common/shapes.h"
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void
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p2t_sweep_init (P2tSweep* THIS)
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{
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THIS->nodes_ = g_ptr_array_new ();
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}
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P2tSweep*
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p2t_sweep_new ()
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{
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P2tSweep* THIS = g_new (P2tSweep, 1);
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p2t_sweep_init (THIS);
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return THIS;
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}
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/**
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* Destructor - clean up memory
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*/
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void
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p2t_sweep_destroy (P2tSweep* THIS)
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{
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int i;
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/* Clean up memory */
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for (i = 0; i < THIS->nodes_->len; i++)
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{
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p2t_node_free (node_index (THIS->nodes_, i));
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}
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g_ptr_array_free (THIS->nodes_, TRUE);
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}
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void
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p2t_sweep_free (P2tSweep* THIS)
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{
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p2t_sweep_destroy (THIS);
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g_free (THIS);
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}
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/* Triangulate simple polygon with holes */
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void
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p2t_sweep_triangulate (P2tSweep *THIS, P2tSweepContext *tcx)
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{
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p2t_sweepcontext_init_triangulation (tcx);
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p2t_sweepcontext_create_advancingfront (tcx, THIS->nodes_);
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/* Sweep points; build mesh */
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p2t_sweep_sweep_points (THIS, tcx);
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/* Clean up */
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p2t_sweep_finalization_polygon (THIS, tcx);
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}
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void
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p2t_sweep_sweep_points (P2tSweep *THIS, P2tSweepContext *tcx)
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{
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stack_pt++;
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if (stack_pt > STACKPTMAX)
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{
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THROW( MAPTOOL_00001_EXCEPTION );
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}
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int i, j;
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for (i = 1; i < p2t_sweepcontext_point_count (tcx); i++)
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{
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P2tPoint* point = p2t_sweepcontext_get_point (tcx, i);
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P2tNode* node = p2t_sweep_point_event (THIS, tcx, point);
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for (j = 0; j < point->edge_list->len; j++)
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{
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p2t_sweep_edge_event_ed_n (THIS, tcx, edge_index (point->edge_list, j), node);
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}
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}
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stack_pt--;
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}
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void
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p2t_sweep_finalization_polygon (P2tSweep *THIS, P2tSweepContext *tcx)
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{
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/* Get an Internal triangle to start with */
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P2tTriangle* t = p2t_advancingfront_head (p2t_sweepcontext_front (tcx))->next->triangle;
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P2tPoint* p = p2t_advancingfront_head (p2t_sweepcontext_front (tcx))->next->point;
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while (!p2t_triangle_get_constrained_edge_cw (t, p))
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{
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t = p2t_triangle_neighbor_ccw (t, p);
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}
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/* Collect interior triangles constrained by edges */
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p2t_sweepcontext_mesh_clean (tcx, t);
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}
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P2tNode*
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p2t_sweep_point_event (P2tSweep *THIS, P2tSweepContext *tcx, P2tPoint* point)
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{
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P2tNode* node = p2t_sweepcontext_locate_node (tcx, point);
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P2tNode* new_node = p2t_sweep_new_front_triangle (THIS, tcx, point, node);
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/* Only need to check +epsilon since point never have smaller
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* x value than node due to how we fetch nodes from the front */
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if (point->x <= node->point->x + EPSILON)
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{
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p2t_sweep_fill (THIS, tcx, node);
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}
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/*tcx.AddNode(new_node); */
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p2t_sweep_fill_advancingfront (THIS, tcx, new_node);
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return new_node;
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}
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void
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p2t_sweep_edge_event_ed_n (P2tSweep *THIS, P2tSweepContext *tcx, P2tEdge* edge, P2tNode* node)
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{
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tcx->edge_event.constrained_edge = edge;
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tcx->edge_event.right = (edge->p->x > edge->q->x);
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if (node == NULL)
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{
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//printf("EE005a\n");
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THROW( MAPTOOL_00001_EXCEPTION );
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}
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if (node->triangle == NULL)
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{
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//printf("EE005b\n");
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THROW( MAPTOOL_00001_EXCEPTION );
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}
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if (p2t_sweep_is_edge_side_of_triangle (THIS, node->triangle, edge->p, edge->q))
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{
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return;
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}
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/* For now we will do all needed filling
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* TODO: integrate with flip process might give some better performance
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* but for now this avoid the issue with cases that needs both flips and fills
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*/
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p2t_sweep_fill_edge_event (THIS, tcx, edge, node);
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p2t_sweep_edge_event_pt_pt_tr_pt (THIS, tcx, edge->p, edge->q, node->triangle, edge->q);
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}
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void
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p2t_sweep_edge_event_pt_pt_tr_pt (P2tSweep *THIS, P2tSweepContext *tcx, P2tPoint* ep, P2tPoint* eq, P2tTriangle* triangle, P2tPoint* point)
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{
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P2tPoint *p1, *p2;
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P2tOrientation o1, o2;
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if (triangle == NULL)
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{
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//printf("EE001\n");
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THROW( MAPTOOL_00001_EXCEPTION );
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}
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if (p2t_sweep_is_edge_side_of_triangle (THIS, triangle, ep, eq))
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{
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return;
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}
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p1 = p2t_triangle_point_ccw (triangle, point);
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o1 = p2t_orient2d (eq, p1, ep);
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if (o1 == COLLINEAR)
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{
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if (p2t_triangle_contains_pt_pt (triangle, eq, p1))
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{
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p2t_triangle_mark_constrained_edge_pt_pt (triangle, eq, p1);
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/* We are modifying the constraint maybe it would be better to
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* not change the given constraint and just keep a variable for the new constraint
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*/
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tcx->edge_event.constrained_edge->q = p1;
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triangle = p2t_triangle_neighbor_across (triangle, point);
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p2t_sweep_edge_event_pt_pt_tr_pt (THIS, tcx, ep, p1, triangle, p1);
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}
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else
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{
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g_error ("EdgeEvent - collinear points not supported");
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}
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return;
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}
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p2 = p2t_triangle_point_cw (triangle, point);
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o2 = p2t_orient2d (eq, p2, ep);
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if (o2 == COLLINEAR)
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{
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if (p2t_triangle_contains_pt_pt (triangle, eq, p2))
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{
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p2t_triangle_mark_constrained_edge_pt_pt (triangle, eq, p2);
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/* We are modifying the constraint maybe it would be better to
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* not change the given constraint and just keep a variable for the new constraint
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*/
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tcx->edge_event.constrained_edge->q = p2;
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triangle = p2t_triangle_neighbor_across (triangle, point);
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p2t_sweep_edge_event_pt_pt_tr_pt (THIS, tcx, ep, p2, triangle, p2);
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}
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else
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{
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g_error ("EdgeEvent - collinear points not supported");
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}
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return;
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}
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if (o1 == o2)
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{
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/* Need to decide if we are rotating CW or CCW to get to a triangle
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* that will cross edge */
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if (o1 == CW)
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{
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triangle = p2t_triangle_neighbor_ccw (triangle, point);
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}
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else
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{
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triangle = p2t_triangle_neighbor_cw (triangle, point);
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}
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p2t_sweep_edge_event_pt_pt_tr_pt (THIS, tcx, ep, eq, triangle, point);
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}
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else
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{
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/* This triangle crosses constraint so lets flippin start! */
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p2t_sweep_flip_edge_event (THIS, tcx, ep, eq, triangle, point);
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}
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}
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gboolean
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p2t_sweep_is_edge_side_of_triangle (P2tSweep *THIS, P2tTriangle *triangle, P2tPoint* ep, P2tPoint* eq)
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{
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int index = p2t_triangle_edge_index (triangle, ep, eq);
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if (index != -1)
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{
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P2tTriangle *t;
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p2t_triangle_mark_constrained_edge_i (triangle, index);
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t = p2t_triangle_get_neighbor (triangle, index);
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if (t)
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{
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p2t_triangle_mark_constrained_edge_pt_pt (t, ep, eq);
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}
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return TRUE;
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}
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return FALSE;
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}
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P2tNode*
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p2t_sweep_new_front_triangle (P2tSweep *THIS, P2tSweepContext *tcx, P2tPoint* point, P2tNode *node)
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{
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P2tTriangle* triangle = p2t_triangle_new (point, node->point, node->next->point);
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P2tNode *new_node;
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p2t_triangle_mark_neighbor_tr (triangle, node->triangle);
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p2t_sweepcontext_add_to_map (tcx, triangle);
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new_node = p2t_node_new_pt (point);
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g_ptr_array_add (THIS->nodes_, new_node);
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new_node->next = node->next;
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new_node->prev = node;
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node->next->prev = new_node;
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node->next = new_node;
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if (!p2t_sweep_legalize (THIS, tcx, triangle))
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{
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p2t_sweepcontext_map_triangle_to_nodes (tcx, triangle);
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}
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return new_node;
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}
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void
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p2t_sweep_fill (P2tSweep *THIS, P2tSweepContext *tcx, P2tNode* node)
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{
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P2tTriangle* triangle = p2t_triangle_new (node->prev->point, node->point, node->next->point);
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/* TODO: should copy the constrained_edge value from neighbor triangles
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* for now constrained_edge values are copied during the legalize */
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p2t_triangle_mark_neighbor_tr (triangle, node->prev->triangle);
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p2t_triangle_mark_neighbor_tr (triangle, node->triangle);
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p2t_sweepcontext_add_to_map (tcx, triangle);
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/* Update the advancing front */
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node->prev->next = node->next;
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node->next->prev = node->prev;
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/* If it was legalized the triangle has already been mapped */
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if (!p2t_sweep_legalize (THIS, tcx, triangle))
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{
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p2t_sweepcontext_map_triangle_to_nodes (tcx, triangle);
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}
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329 |
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}
|
331 |
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void
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p2t_sweep_fill_advancingfront (P2tSweep *THIS, P2tSweepContext *tcx, P2tNode* n)
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{
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335 |
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336 |
/* Fill right holes */
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337 |
P2tNode* node = n->next;
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338 |
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while (node->next)
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{
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341 |
/* if HoleAngle exceeds 90 degrees then break. */
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if (p2t_sweep_large_hole_dont_fill (THIS, node)) break;
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p2t_sweep_fill (THIS, tcx, node);
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node = node->next;
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}
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346 |
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/* Fill left holes */
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348 |
node = n->prev;
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349 |
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350 |
while (node->prev)
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{
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352 |
/* if HoleAngle exceeds 90 degrees then break. */
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353 |
if (p2t_sweep_large_hole_dont_fill (THIS, node)) break;
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354 |
p2t_sweep_fill (THIS, tcx, node);
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node = node->prev;
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}
|
357 |
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358 |
/* Fill right basins */
|
359 |
if (n->next && n->next->next)
|
360 |
{
|
361 |
double angle = p2t_sweep_basin_angle (THIS, n);
|
362 |
if (angle < PI_3div4)
|
363 |
{
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364 |
p2t_sweep_fill_basin (THIS, tcx, n);
|
365 |
}
|
366 |
}
|
367 |
}
|
368 |
|
369 |
/* True if HoleAngle exceeds 90 degrees. */
|
370 |
gboolean
|
371 |
p2t_sweep_large_hole_dont_fill (P2tSweep *THIS, P2tNode* node)
|
372 |
{
|
373 |
P2tNode* nextNode = node->next;
|
374 |
P2tNode* prevNode = node->prev;
|
375 |
P2tNode *next2Node, *prev2Node;
|
376 |
if (! p2t_sweep_angle_exceeds_90_degrees (THIS, node->point, nextNode->point, prevNode->point))
|
377 |
return FALSE;
|
378 |
|
379 |
/* Check additional points on front. */
|
380 |
next2Node = nextNode->next;
|
381 |
/* "..Plus.." because only want angles on same side as point being added. */
|
382 |
if ((next2Node != NULL) && !p2t_sweep_angle_exceeds_plus_90_degrees_or_is_negative (THIS, node->point, next2Node->point, prevNode->point))
|
383 |
return FALSE;
|
384 |
|
385 |
prev2Node = prevNode->prev;
|
386 |
/* "..Plus.." because only want angles on same side as point being added. */
|
387 |
if ((prev2Node != NULL) && !p2t_sweep_angle_exceeds_plus_90_degrees_or_is_negative (THIS, node->point, nextNode->point, prev2Node->point))
|
388 |
return FALSE;
|
389 |
|
390 |
return TRUE;
|
391 |
}
|
392 |
|
393 |
gboolean
|
394 |
p2t_sweep_angle_exceeds_90_degrees(P2tSweep* THIS, P2tPoint* origin, P2tPoint* pa, P2tPoint* pb)
|
395 |
{
|
396 |
gdouble angle = p2t_sweep_angle (THIS, origin, pa, pb);
|
397 |
gboolean exceeds90Degrees = ((angle > G_PI_2) || (angle < -G_PI_2));
|
398 |
return exceeds90Degrees;
|
399 |
}
|
400 |
|
401 |
gboolean
|
402 |
p2t_sweep_angle_exceeds_plus_90_degrees_or_is_negative (P2tSweep* THIS, P2tPoint* origin, P2tPoint* pa, P2tPoint* pb)
|
403 |
{
|
404 |
gdouble angle = p2t_sweep_angle (THIS, origin, pa, pb);
|
405 |
gboolean exceedsPlus90DegreesOrIsNegative = (angle > G_PI_2) || (angle < 0);
|
406 |
return exceedsPlus90DegreesOrIsNegative;
|
407 |
}
|
408 |
|
409 |
gdouble
|
410 |
p2t_sweep_angle (P2tSweep* THIS, P2tPoint* origin, P2tPoint* pa, P2tPoint* pb) {
|
411 |
/* Complex plane
|
412 |
* ab = cosA +i*sinA
|
413 |
* ab = (ax + ay*i)(bx + by*i) = (ax*bx + ay*by) + i(ax*by-ay*bx)
|
414 |
* atan2(y,x) computes the principal value of the argument function
|
415 |
* applied to the complex number x+iy
|
416 |
* Where x = ax*bx + ay*by
|
417 |
* y = ax*by - ay*bx
|
418 |
*/
|
419 |
double px = origin->x;
|
420 |
double py = origin->y;
|
421 |
double ax = pa->x - px;
|
422 |
double ay = pa->y - py;
|
423 |
double bx = pb->x - px;
|
424 |
double by = pb->y - py;
|
425 |
double x = ax * by - ay * bx;
|
426 |
double y = ax * bx + ay * by;
|
427 |
double angle = atan2(x, y);
|
428 |
return angle;
|
429 |
}
|
430 |
|
431 |
double
|
432 |
p2t_sweep_basin_angle (P2tSweep *THIS, P2tNode* node)
|
433 |
{
|
434 |
double ax = node->point->x - node->next->next->point->x;
|
435 |
double ay = node->point->y - node->next->next->point->y;
|
436 |
return atan2 (ay, ax);
|
437 |
}
|
438 |
|
439 |
double
|
440 |
p2t_sweep_hole_angle (P2tSweep *THIS, P2tNode* node)
|
441 |
{
|
442 |
/* Complex plane
|
443 |
* ab = cosA +i*sinA
|
444 |
* ab = (ax + ay*i)(bx + by*i) = (ax*bx + ay*by) + i(ax*by-ay*bx)
|
445 |
* atan2(y,x) computes the principal value of the argument function
|
446 |
* applied to the complex number x+iy
|
447 |
* Where x = ax*bx + ay*by
|
448 |
* y = ax*by - ay*bx
|
449 |
*/
|
450 |
double ax = node->next->point->x - node->point->x;
|
451 |
double ay = node->next->point->y - node->point->y;
|
452 |
double bx = node->prev->point->x - node->point->x;
|
453 |
double by = node->prev->point->y - node->point->y;
|
454 |
return atan2 (ax * by - ay * bx, ax * bx + ay * by);
|
455 |
}
|
456 |
|
457 |
gboolean
|
458 |
p2t_sweep_legalize (P2tSweep *THIS, P2tSweepContext *tcx, P2tTriangle *t)
|
459 |
{
|
460 |
int i;
|
461 |
/* To legalize a triangle we start by finding if any of the three edges
|
462 |
* violate the Delaunay condition */
|
463 |
for (i = 0; i < 3; i++)
|
464 |
{
|
465 |
P2tTriangle *ot;
|
466 |
|
467 |
if (t->delaunay_edge[i])
|
468 |
continue;
|
469 |
|
470 |
ot = p2t_triangle_get_neighbor (t, i);
|
471 |
|
472 |
if (ot)
|
473 |
{
|
474 |
P2tPoint* p = p2t_triangle_get_point (t, i);
|
475 |
P2tPoint* op = p2t_triangle_opposite_point (ot, t, p);
|
476 |
int oi = p2t_triangle_index (ot, op);
|
477 |
gboolean inside;
|
478 |
|
479 |
/* If this is a Constrained Edge or a Delaunay Edge(only during recursive legalization)
|
480 |
* then we should not try to legalize */
|
481 |
if (ot->constrained_edge[oi] || ot->delaunay_edge[oi])
|
482 |
{
|
483 |
t->constrained_edge[i] = ot->constrained_edge[oi];
|
484 |
continue;
|
485 |
}
|
486 |
|
487 |
inside = p2t_sweep_incircle (THIS, p, p2t_triangle_point_ccw (t, p), p2t_triangle_point_cw (t, p), op);
|
488 |
|
489 |
if (inside)
|
490 |
{
|
491 |
gboolean not_legalized;
|
492 |
/* Lets mark this shared edge as Delaunay */
|
493 |
t->delaunay_edge[i] = TRUE;
|
494 |
ot->delaunay_edge[oi] = TRUE;
|
495 |
|
496 |
/* Lets rotate shared edge one vertex CW to legalize it */
|
497 |
p2t_sweep_rotate_triangle_pair (THIS, t, p, ot, op);
|
498 |
|
499 |
/* We now got one valid Delaunay Edge shared by two triangles
|
500 |
* This gives us 4 new edges to check for Delaunay */
|
501 |
|
502 |
/* Make sure that triangle to node mapping is done only one time for a specific triangle */
|
503 |
not_legalized = !p2t_sweep_legalize (THIS, tcx, t);
|
504 |
if (not_legalized)
|
505 |
{
|
506 |
p2t_sweepcontext_map_triangle_to_nodes (tcx, t);
|
507 |
}
|
508 |
|
509 |
not_legalized = !p2t_sweep_legalize (THIS, tcx, ot);
|
510 |
if (not_legalized)
|
511 |
p2t_sweepcontext_map_triangle_to_nodes (tcx, ot);
|
512 |
|
513 |
/* Reset the Delaunay edges, since they only are valid Delaunay edges
|
514 |
* until we add a new triangle or point.
|
515 |
* XXX: need to think about this. Can these edges be tried after we
|
516 |
* return to previous recursive level? */
|
517 |
t->delaunay_edge[i] = FALSE;
|
518 |
ot->delaunay_edge[oi] = FALSE;
|
519 |
|
520 |
/* If triangle have been legalized no need to check the other edges since
|
521 |
* the recursive legalization will handles those so we can end here.*/
|
522 |
return TRUE;
|
523 |
}
|
524 |
}
|
525 |
}
|
526 |
return FALSE;
|
527 |
}
|
528 |
|
529 |
gboolean
|
530 |
p2t_sweep_incircle (P2tSweep *THIS, P2tPoint* pa, P2tPoint* pb, P2tPoint* pc, P2tPoint* pd)
|
531 |
{
|
532 |
double adx = pa->x - pd->x;
|
533 |
double ady = pa->y - pd->y;
|
534 |
double bdx = pb->x - pd->x;
|
535 |
double bdy = pb->y - pd->y;
|
536 |
|
537 |
double adxbdy = adx * bdy;
|
538 |
double bdxady = bdx * ady;
|
539 |
double oabd = adxbdy - bdxady;
|
540 |
|
541 |
double cdx, cdy;
|
542 |
double cdxady, adxcdy, ocad;
|
543 |
|
544 |
double bdxcdy, cdxbdy;
|
545 |
double alift, blift, clift;
|
546 |
double det;
|
547 |
|
548 |
if (oabd <= 0)
|
549 |
return FALSE;
|
550 |
|
551 |
cdx = pc->x - pd->x;
|
552 |
cdy = pc->y - pd->y;
|
553 |
|
554 |
cdxady = cdx * ady;
|
555 |
adxcdy = adx * cdy;
|
556 |
ocad = cdxady - adxcdy;
|
557 |
|
558 |
if (ocad <= 0)
|
559 |
return FALSE;
|
560 |
|
561 |
bdxcdy = bdx * cdy;
|
562 |
cdxbdy = cdx * bdy;
|
563 |
|
564 |
alift = adx * adx + ady * ady;
|
565 |
blift = bdx * bdx + bdy * bdy;
|
566 |
clift = cdx * cdx + cdy * cdy;
|
567 |
|
568 |
det = alift * (bdxcdy - cdxbdy) + blift * ocad + clift * oabd;
|
569 |
|
570 |
return det > 0;
|
571 |
}
|
572 |
|
573 |
void
|
574 |
p2t_sweep_rotate_triangle_pair (P2tSweep *THIS, P2tTriangle *t, P2tPoint* p, P2tTriangle *ot, P2tPoint* op)
|
575 |
{
|
576 |
P2tTriangle *n1, *n2, *n3, *n4;
|
577 |
gboolean ce1, ce2, ce3, ce4;
|
578 |
gboolean de1, de2, de3, de4;
|
579 |
|
580 |
n1 = p2t_triangle_neighbor_ccw (t, p);
|
581 |
n2 = p2t_triangle_neighbor_cw (t, p);
|
582 |
n3 = p2t_triangle_neighbor_ccw (ot, op);
|
583 |
n4 = p2t_triangle_neighbor_cw (ot, op);
|
584 |
|
585 |
ce1 = p2t_triangle_get_constrained_edge_ccw (t, p);
|
586 |
ce2 = p2t_triangle_get_constrained_edge_cw (t, p);
|
587 |
ce3 = p2t_triangle_get_constrained_edge_ccw (ot, op);
|
588 |
ce4 = p2t_triangle_get_constrained_edge_cw (ot, op);
|
589 |
|
590 |
de1 = p2t_triangle_get_delunay_edge_ccw (t, p);
|
591 |
de2 = p2t_triangle_get_delunay_edge_cw (t, p);
|
592 |
de3 = p2t_triangle_get_delunay_edge_ccw (ot, op);
|
593 |
de4 = p2t_triangle_get_delunay_edge_cw (ot, op);
|
594 |
|
595 |
p2t_triangle_legalize_pt_pt (t, p, op);
|
596 |
p2t_triangle_legalize_pt_pt (ot, op, p);
|
597 |
|
598 |
/* Remap delaunay_edge */
|
599 |
p2t_triangle_set_delunay_edge_ccw (ot, p, de1);
|
600 |
p2t_triangle_set_delunay_edge_cw (t, p, de2);
|
601 |
p2t_triangle_set_delunay_edge_ccw (t, op, de3);
|
602 |
p2t_triangle_set_delunay_edge_cw (ot, op, de4);
|
603 |
|
604 |
/* Remap constrained_edge */
|
605 |
p2t_triangle_set_constrained_edge_ccw (ot, p, ce1);
|
606 |
p2t_triangle_set_constrained_edge_cw (t, p, ce2);
|
607 |
p2t_triangle_set_constrained_edge_ccw (t, op, ce3);
|
608 |
p2t_triangle_set_constrained_edge_cw (ot, op, ce4);
|
609 |
|
610 |
/* Remap neighbors
|
611 |
* XXX: might optimize the markNeighbor by keeping track of
|
612 |
* what side should be assigned to what neighbor after the
|
613 |
* rotation. Now mark neighbor does lots of testing to find
|
614 |
* the right side. */
|
615 |
p2t_triangle_clear_neighbors (t);
|
616 |
p2t_triangle_clear_neighbors (ot);
|
617 |
if (n1) p2t_triangle_mark_neighbor_tr (ot, n1);
|
618 |
if (n2) p2t_triangle_mark_neighbor_tr (t, n2);
|
619 |
if (n3) p2t_triangle_mark_neighbor_tr (t, n3);
|
620 |
if (n4) p2t_triangle_mark_neighbor_tr (ot, n4);
|
621 |
p2t_triangle_mark_neighbor_tr (t, ot);
|
622 |
}
|
623 |
|
624 |
void
|
625 |
p2t_sweep_fill_basin (P2tSweep *THIS, P2tSweepContext *tcx, P2tNode* node)
|
626 |
{
|
627 |
if (p2t_orient2d (node->point, node->next->point, node->next->next->point) == CCW)
|
628 |
{
|
629 |
tcx->basin.left_node = node->next->next;
|
630 |
}
|
631 |
else
|
632 |
{
|
633 |
tcx->basin.left_node = node->next;
|
634 |
}
|
635 |
|
636 |
/* Find the bottom and right node */
|
637 |
tcx->basin.bottom_node = tcx->basin.left_node;
|
638 |
while (tcx->basin.bottom_node->next
|
639 |
&& tcx->basin.bottom_node->point->y >= tcx->basin.bottom_node->next->point->y)
|
640 |
{
|
641 |
tcx->basin.bottom_node = tcx->basin.bottom_node->next;
|
642 |
}
|
643 |
if (tcx->basin.bottom_node == tcx->basin.left_node)
|
644 |
{
|
645 |
/* No valid basin */
|
646 |
return;
|
647 |
}
|
648 |
|
649 |
tcx->basin.right_node = tcx->basin.bottom_node;
|
650 |
while (tcx->basin.right_node->next
|
651 |
&& tcx->basin.right_node->point->y < tcx->basin.right_node->next->point->y)
|
652 |
{
|
653 |
tcx->basin.right_node = tcx->basin.right_node->next;
|
654 |
}
|
655 |
if (tcx->basin.right_node == tcx->basin.bottom_node)
|
656 |
{
|
657 |
/* No valid basins */
|
658 |
return;
|
659 |
}
|
660 |
|
661 |
tcx->basin.width = tcx->basin.right_node->point->x - tcx->basin.left_node->point->x;
|
662 |
tcx->basin.left_highest = tcx->basin.left_node->point->y > tcx->basin.right_node->point->y;
|
663 |
|
664 |
p2t_sweep_fill_basin_req (THIS, tcx, tcx->basin.bottom_node);
|
665 |
}
|
666 |
|
667 |
void
|
668 |
p2t_sweep_fill_basin_req (P2tSweep *THIS, P2tSweepContext *tcx, P2tNode* node)
|
669 |
{
|
670 |
/* if shallow stop filling */
|
671 |
if (p2t_sweep_is_shallow (THIS, tcx, node))
|
672 |
{
|
673 |
return;
|
674 |
}
|
675 |
|
676 |
p2t_sweep_fill (THIS, tcx, node);
|
677 |
|
678 |
if (node->prev == tcx->basin.left_node && node->next == tcx->basin.right_node)
|
679 |
{
|
680 |
return;
|
681 |
}
|
682 |
else if (node->prev == tcx->basin.left_node)
|
683 |
{
|
684 |
P2tOrientation o = p2t_orient2d (node->point, node->next->point, node->next->next->point);
|
685 |
if (o == CW)
|
686 |
{
|
687 |
return;
|
688 |
}
|
689 |
node = node->next;
|
690 |
}
|
691 |
else if (node->next == tcx->basin.right_node)
|
692 |
{
|
693 |
P2tOrientation o = p2t_orient2d (node->point, node->prev->point, node->prev->prev->point);
|
694 |
if (o == CCW)
|
695 |
{
|
696 |
return;
|
697 |
}
|
698 |
node = node->prev;
|
699 |
}
|
700 |
else
|
701 |
{
|
702 |
/* Continue with the neighbor node with lowest Y value */
|
703 |
if (node->prev->point->y < node->next->point->y)
|
704 |
{
|
705 |
node = node->prev;
|
706 |
}
|
707 |
else
|
708 |
{
|
709 |
node = node->next;
|
710 |
}
|
711 |
}
|
712 |
|
713 |
p2t_sweep_fill_basin_req (THIS, tcx, node);
|
714 |
}
|
715 |
|
716 |
gboolean
|
717 |
p2t_sweep_is_shallow (P2tSweep *THIS, P2tSweepContext *tcx, P2tNode* node)
|
718 |
{
|
719 |
|
720 |
|
721 |
double height;
|
722 |
|
723 |
if (tcx->basin.left_highest)
|
724 |
{
|
725 |
height = tcx->basin.left_node->point->y - node->point->y;
|
726 |
}
|
727 |
else
|
728 |
{
|
729 |
height = tcx->basin.right_node->point->y - node->point->y;
|
730 |
}
|
731 |
|
732 |
/* if shallow stop filling */
|
733 |
if (tcx->basin.width > height)
|
734 |
{
|
735 |
return TRUE;
|
736 |
}
|
737 |
return FALSE;
|
738 |
}
|
739 |
|
740 |
void
|
741 |
p2t_sweep_fill_edge_event (P2tSweep *THIS, P2tSweepContext *tcx, P2tEdge* edge, P2tNode* node)
|
742 |
{
|
743 |
|
744 |
|
745 |
if (tcx->edge_event.right)
|
746 |
{
|
747 |
p2t_sweep_fill_right_above_edge_event (THIS, tcx, edge, node);
|
748 |
}
|
749 |
else
|
750 |
{
|
751 |
p2t_sweep_fill_left_above_edge_event (THIS, tcx, edge, node);
|
752 |
}
|
753 |
}
|
754 |
|
755 |
void
|
756 |
p2t_sweep_fill_right_above_edge_event (P2tSweep *THIS, P2tSweepContext *tcx, P2tEdge* edge, P2tNode* node)
|
757 |
{
|
758 |
while (node->next->point->x < edge->p->x)
|
759 |
{
|
760 |
/* Check if next node is below the edge */
|
761 |
if (p2t_orient2d (edge->q, node->next->point, edge->p) == CCW)
|
762 |
{
|
763 |
p2t_sweep_fill_right_below_edge_event (THIS, tcx, edge, node);
|
764 |
}
|
765 |
else
|
766 |
{
|
767 |
node = node->next;
|
768 |
}
|
769 |
}
|
770 |
}
|
771 |
|
772 |
void
|
773 |
p2t_sweep_fill_right_below_edge_event (P2tSweep *THIS, P2tSweepContext *tcx, P2tEdge* edge, P2tNode* node)
|
774 |
{
|
775 |
if (node->point->x < edge->p->x)
|
776 |
{
|
777 |
if (p2t_orient2d (node->point, node->next->point, node->next->next->point) == CCW)
|
778 |
{
|
779 |
/* Concave */
|
780 |
p2t_sweep_fill_right_concave_edge_event (THIS, tcx, edge, node);
|
781 |
}
|
782 |
else
|
783 |
{
|
784 |
/* Convex */
|
785 |
p2t_sweep_fill_right_convex_edge_event (THIS, tcx, edge, node);
|
786 |
/* Retry this one */
|
787 |
p2t_sweep_fill_right_below_edge_event (THIS, tcx, edge, node);
|
788 |
}
|
789 |
}
|
790 |
}
|
791 |
|
792 |
void
|
793 |
p2t_sweep_fill_right_concave_edge_event (P2tSweep *THIS, P2tSweepContext *tcx, P2tEdge* edge, P2tNode* node)
|
794 |
{
|
795 |
p2t_sweep_fill (THIS, tcx, node->next);
|
796 |
if (node->next->point != edge->p)
|
797 |
{
|
798 |
/* Next above or below edge? */
|
799 |
if (p2t_orient2d (edge->q, node->next->point, edge->p) == CCW)
|
800 |
{
|
801 |
/* Below */
|
802 |
if (p2t_orient2d (node->point, node->next->point, node->next->next->point) == CCW)
|
803 |
{
|
804 |
/* Next is concave */
|
805 |
p2t_sweep_fill_right_concave_edge_event (THIS, tcx, edge, node);
|
806 |
}
|
807 |
else
|
808 |
{
|
809 |
/* Next is convex */
|
810 |
}
|
811 |
}
|
812 |
}
|
813 |
|
814 |
}
|
815 |
|
816 |
void
|
817 |
p2t_sweep_fill_right_convex_edge_event (P2tSweep *THIS, P2tSweepContext *tcx, P2tEdge* edge, P2tNode* node)
|
818 |
{
|
819 |
/* Next concave or convex? */
|
820 |
if (p2t_orient2d (node->next->point, node->next->next->point, node->next->next->next->point) == CCW)
|
821 |
{
|
822 |
/* Concave */
|
823 |
p2t_sweep_fill_right_concave_edge_event (THIS, tcx, edge, node->next);
|
824 |
}
|
825 |
else
|
826 |
{
|
827 |
/* Convex
|
828 |
* Next above or below edge? */
|
829 |
if (p2t_orient2d (edge->q, node->next->next->point, edge->p) == CCW)
|
830 |
{
|
831 |
/* Below */
|
832 |
p2t_sweep_fill_right_convex_edge_event (THIS, tcx, edge, node->next);
|
833 |
}
|
834 |
else
|
835 |
{
|
836 |
/* Above */
|
837 |
}
|
838 |
}
|
839 |
}
|
840 |
|
841 |
void
|
842 |
p2t_sweep_fill_left_above_edge_event (P2tSweep *THIS, P2tSweepContext *tcx, P2tEdge* edge, P2tNode* node)
|
843 |
{
|
844 |
while (node->prev->point->x > edge->p->x)
|
845 |
{
|
846 |
/* Check if next node is below the edge */
|
847 |
if (p2t_orient2d (edge->q, node->prev->point, edge->p) == CW)
|
848 |
{
|
849 |
p2t_sweep_fill_left_below_edge_event (THIS, tcx, edge, node);
|
850 |
}
|
851 |
else
|
852 |
{
|
853 |
node = node->prev;
|
854 |
}
|
855 |
}
|
856 |
}
|
857 |
|
858 |
void
|
859 |
p2t_sweep_fill_left_below_edge_event (P2tSweep *THIS, P2tSweepContext *tcx, P2tEdge* edge, P2tNode* node)
|
860 |
{
|
861 |
if (node->point->x > edge->p->x)
|
862 |
{
|
863 |
if (p2t_orient2d (node->point, node->prev->point, node->prev->prev->point) == CW)
|
864 |
{
|
865 |
/* Concave */
|
866 |
p2t_sweep_fill_left_concave_edge_event (THIS, tcx, edge, node);
|
867 |
}
|
868 |
else
|
869 |
{
|
870 |
/* Convex */
|
871 |
p2t_sweep_fill_left_convex_edge_event (THIS, tcx, edge, node);
|
872 |
/* Retry this one */
|
873 |
p2t_sweep_fill_left_below_edge_event (THIS, tcx, edge, node);
|
874 |
}
|
875 |
}
|
876 |
}
|
877 |
|
878 |
void
|
879 |
p2t_sweep_fill_left_convex_edge_event (P2tSweep *THIS, P2tSweepContext *tcx, P2tEdge* edge, P2tNode* node)
|
880 |
{
|
881 |
|
882 |
|
883 |
/* Next concave or convex? */
|
884 |
if (p2t_orient2d (node->prev->point, node->prev->prev->point, node->prev->prev->prev->point) == CW)
|
885 |
{
|
886 |
/* Concave */
|
887 |
p2t_sweep_fill_left_concave_edge_event (THIS, tcx, edge, node->prev);
|
888 |
}
|
889 |
else
|
890 |
{
|
891 |
/* Convex
|
892 |
* Next above or below edge? */
|
893 |
if (p2t_orient2d (edge->q, node->prev->prev->point, edge->p) == CW)
|
894 |
{
|
895 |
/* Below */
|
896 |
p2t_sweep_fill_left_convex_edge_event (THIS, tcx, edge, node->prev);
|
897 |
}
|
898 |
else
|
899 |
{
|
900 |
/* Above */
|
901 |
}
|
902 |
}
|
903 |
}
|
904 |
|
905 |
void
|
906 |
p2t_sweep_fill_left_concave_edge_event (P2tSweep *THIS, P2tSweepContext *tcx, P2tEdge* edge, P2tNode* node)
|
907 |
{
|
908 |
|
909 |
|
910 |
p2t_sweep_fill (THIS, tcx, node->prev);
|
911 |
if (node->prev->point != edge->p)
|
912 |
{
|
913 |
/* Next above or below edge? */
|
914 |
if (p2t_orient2d (edge->q, node->prev->point, edge->p) == CW)
|
915 |
{
|
916 |
/* Below */
|
917 |
if (p2t_orient2d (node->point, node->prev->point, node->prev->prev->point) == CW)
|
918 |
{
|
919 |
/* Next is concave */
|
920 |
p2t_sweep_fill_left_concave_edge_event (THIS, tcx, edge, node);
|
921 |
}
|
922 |
else
|
923 |
{
|
924 |
/* Next is convex */
|
925 |
}
|
926 |
}
|
927 |
}
|
928 |
|
929 |
}
|
930 |
|
931 |
void
|
932 |
p2t_sweep_flip_edge_event (P2tSweep *THIS, P2tSweepContext *tcx, P2tPoint* ep, P2tPoint* eq, P2tTriangle* t, P2tPoint* p)
|
933 |
{
|
934 |
stack_pt++;
|
935 |
if (stack_pt > STACKPTMAX)
|
936 |
{
|
937 |
THROW( MAPTOOL_00001_EXCEPTION );
|
938 |
}
|
939 |
|
940 |
|
941 |
P2tTriangle* ot = p2t_triangle_neighbor_across (t, p);
|
942 |
P2tPoint* op = p2t_triangle_opposite_point (ot, t, p);
|
943 |
|
944 |
if (ot == NULL)
|
945 |
{
|
946 |
/* If we want to integrate the fillEdgeEvent do it here
|
947 |
* With current implementation we should never get here
|
948 |
*throw new RuntimeException( "[BUG:FIXME] FLIP failed due to missing triangle");
|
949 |
*/
|
950 |
fprintf(stderr, "EE002\n");
|
951 |
THROW( MAPTOOL_00001_EXCEPTION );
|
952 |
|
953 |
assert (0);
|
954 |
}
|
955 |
|
956 |
|
957 |
|
958 |
if (p2t_utils_in_scan_area (p, p2t_triangle_point_ccw (t, p), p2t_triangle_point_cw (t, p), op))
|
959 |
{
|
960 |
|
961 |
/* Lets rotate shared edge one vertex CW */
|
962 |
p2t_sweep_rotate_triangle_pair (THIS, t, p, ot, op);
|
963 |
p2t_sweepcontext_map_triangle_to_nodes (tcx, t);
|
964 |
p2t_sweepcontext_map_triangle_to_nodes (tcx, ot);
|
965 |
|
966 |
|
967 |
if (p == eq && op == ep)
|
968 |
{
|
969 |
if (p2t_point_equals (eq, tcx->edge_event.constrained_edge->q) && p2t_point_equals (ep, tcx->edge_event.constrained_edge->p))
|
970 |
{
|
971 |
|
972 |
p2t_triangle_mark_constrained_edge_pt_pt (t, ep, eq);
|
973 |
p2t_triangle_mark_constrained_edge_pt_pt (ot, ep, eq);
|
974 |
p2t_sweep_legalize (THIS, tcx, t);
|
975 |
p2t_sweep_legalize (THIS, tcx, ot);
|
976 |
|
977 |
}
|
978 |
else
|
979 |
{
|
980 |
/* XXX: I think one of the triangles should be legalized here? */
|
981 |
|
982 |
}
|
983 |
}
|
984 |
else
|
985 |
{
|
986 |
|
987 |
P2tOrientation o = p2t_orient2d (eq, op, ep);
|
988 |
t = p2t_sweep_next_flip_triangle (THIS, tcx, (int) o, t, ot, p, op);
|
989 |
p2t_sweep_flip_edge_event (THIS, tcx, ep, eq, t, p);
|
990 |
|
991 |
}
|
992 |
}
|
993 |
else
|
994 |
{
|
995 |
|
996 |
P2tPoint* newP = p2t_sweep_next_flip_point (THIS, ep, eq, ot, op);
|
997 |
|
998 |
p2t_sweep_flip_scan_edge_event (THIS, tcx, ep, eq, t, ot, newP);
|
999 |
|
1000 |
p2t_sweep_edge_event_pt_pt_tr_pt (THIS, tcx, ep, eq, t, p);
|
1001 |
|
1002 |
}
|
1003 |
|
1004 |
stack_pt--;
|
1005 |
|
1006 |
}
|
1007 |
|
1008 |
P2tTriangle*
|
1009 |
p2t_sweep_next_flip_triangle (P2tSweep *THIS, P2tSweepContext *tcx, int o, P2tTriangle *t, P2tTriangle *ot, P2tPoint* p, P2tPoint* op)
|
1010 |
{
|
1011 |
|
1012 |
|
1013 |
int edge_index;
|
1014 |
|
1015 |
if (o == CCW)
|
1016 |
{
|
1017 |
/* ot is not crossing edge after flip */
|
1018 |
int edge_index = p2t_triangle_edge_index (ot, p, op);
|
1019 |
ot->delaunay_edge[edge_index] = TRUE;
|
1020 |
p2t_sweep_legalize (THIS, tcx, ot);
|
1021 |
p2t_triangle_clear_delunay_edges (ot);
|
1022 |
return t;
|
1023 |
}
|
1024 |
|
1025 |
/* t is not crossing edge after flip */
|
1026 |
edge_index = p2t_triangle_edge_index (t, p, op);
|
1027 |
|
1028 |
t->delaunay_edge[edge_index] = TRUE;
|
1029 |
p2t_sweep_legalize (THIS, tcx, t);
|
1030 |
p2t_triangle_clear_delunay_edges (t);
|
1031 |
return ot;
|
1032 |
}
|
1033 |
|
1034 |
P2tPoint*
|
1035 |
p2t_sweep_next_flip_point (P2tSweep *THIS, P2tPoint* ep, P2tPoint* eq, P2tTriangle *ot, P2tPoint* op)
|
1036 |
{
|
1037 |
|
1038 |
stack_pt++;
|
1039 |
if (stack_pt > STACKPTMAX)
|
1040 |
{
|
1041 |
THROW( MAPTOOL_00001_EXCEPTION );
|
1042 |
}
|
1043 |
|
1044 |
|
1045 |
P2tOrientation o2d = p2t_orient2d (eq, op, ep);
|
1046 |
if (o2d == CW)
|
1047 |
{
|
1048 |
/* Right */
|
1049 |
return p2t_triangle_point_ccw (ot, op);
|
1050 |
}
|
1051 |
else if (o2d == CCW)
|
1052 |
{
|
1053 |
/* Left */
|
1054 |
return p2t_triangle_point_cw (ot, op);
|
1055 |
}
|
1056 |
else
|
1057 |
{
|
1058 |
/*throw new RuntimeException("[Unsupported] Opposing point on constrained edge");*/
|
1059 |
//printf("EE003\n");
|
1060 |
THROW( MAPTOOL_00001_EXCEPTION );
|
1061 |
|
1062 |
assert (0);
|
1063 |
}
|
1064 |
|
1065 |
stack_pt--;
|
1066 |
}
|
1067 |
|
1068 |
void
|
1069 |
p2t_sweep_flip_scan_edge_event (P2tSweep *THIS, P2tSweepContext *tcx, P2tPoint* ep, P2tPoint* eq, P2tTriangle *flip_triangle,
|
1070 |
P2tTriangle *t, P2tPoint* p)
|
1071 |
{
|
1072 |
|
1073 |
stack_pt++;
|
1074 |
if (stack_pt > STACKPTMAX)
|
1075 |
{
|
1076 |
THROW( MAPTOOL_00001_EXCEPTION );
|
1077 |
}
|
1078 |
|
1079 |
|
1080 |
P2tTriangle* ot = p2t_triangle_neighbor_across (t, p);
|
1081 |
|
1082 |
P2tPoint* op = p2t_triangle_opposite_point (ot, t, p);
|
1083 |
|
1084 |
|
1085 |
if (p2t_triangle_neighbor_across (t, p) == NULL)
|
1086 |
{
|
1087 |
/* If we want to integrate the fillEdgeEvent do it here
|
1088 |
* With current implementation we should never get here
|
1089 |
*throw new RuntimeException( "[BUG:FIXME] FLIP failed due to missing triangle");
|
1090 |
*/
|
1091 |
//printf("EE004\n");
|
1092 |
THROW( MAPTOOL_00001_EXCEPTION );
|
1093 |
|
1094 |
assert (0);
|
1095 |
}
|
1096 |
|
1097 |
|
1098 |
if (p2t_utils_in_scan_area (eq, p2t_triangle_point_ccw (flip_triangle, eq), p2t_triangle_point_cw (flip_triangle, eq), op))
|
1099 |
{
|
1100 |
/* flip with new edge op->eq */
|
1101 |
|
1102 |
p2t_sweep_flip_edge_event (THIS, tcx, eq, op, ot, op);
|
1103 |
|
1104 |
/* TODO: Actually I just figured out that it should be possible to
|
1105 |
* improve this by getting the next ot and op before the the above
|
1106 |
* flip and continue the flipScanEdgeEvent here
|
1107 |
* set new ot and op here and loop back to inScanArea test
|
1108 |
* also need to set a new flip_triangle first
|
1109 |
* Turns out at first glance that this is somewhat complicated
|
1110 |
* so it will have to wait. */
|
1111 |
}
|
1112 |
else
|
1113 |
{
|
1114 |
|
1115 |
P2tPoint* newP = p2t_sweep_next_flip_point (THIS, ep, eq, ot, op);
|
1116 |
|
1117 |
p2t_sweep_flip_scan_edge_event (THIS, tcx, ep, eq, flip_triangle, ot, newP);
|
1118 |
|
1119 |
}
|
1120 |
|
1121 |
stack_pt--;
|
1122 |
|
1123 |
|
1124 |
}
|
1125 |
|