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@ -36,31 +36,67 @@
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#include "sweep_context.h"
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#include "sweep.h"
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/**
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*
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* @author Mason Green <mason.green@gmail.com>
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*
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*/
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namespace p2t {
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class CDT
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{
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public:
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/// Constructor
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CDT(std::vector<Point*> polyline);
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/// Destructor
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~CDT();
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/// Add a hole
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void AddHole(std::vector<Point*> polyline);
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/// Add a single point
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void AddPoint(Point* point);
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/// Triangulate points
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void Triangulate();
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/// Get Delaunay triangles
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std::vector<Triangle*> GetTriangles();
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/// Get triangle map
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std::list<Triangle*> GetMap();
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/**
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* Constructor - add polyline with non repeating points
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*
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* @param polyline
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*/
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CDT(std::vector<Point*> polyline);
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/**
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* Destructor - clean up memory
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*/
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~CDT();
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/**
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* Add a hole
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*
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* @param polyline
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*/
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void AddHole(std::vector<Point*> polyline);
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/**
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* Add a steiner point
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*
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* @param point
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*/
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void AddPoint(Point* point);
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/**
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* Triangulate - do this AFTER you've added the polyline, holes, and Steiner points
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*/
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void Triangulate();
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/**
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* Get CDT triangles
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*/
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std::vector<Triangle*> GetTriangles();
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/**
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* Get triangle map
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*/
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std::list<Triangle*> GetMap();
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private:
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private:
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SweepContext* sweep_context_;
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Sweep* sweep_;
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/**
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* Internals
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*/
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SweepContext* sweep_context_;
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Sweep* sweep_;
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};
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@ -71,15 +71,6 @@ void Sweep::FinalizationPolygon(SweepContext& tcx)
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tcx.MeshClean(*t);
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}
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/**
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* Find closes node to the left of the new point and
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* create a new triangle. If needed new holes and basins
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* will be filled to.
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*
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* @param tcx
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* @param point
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* @return
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*/
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Node& Sweep::PointEvent(SweepContext& tcx, Point& point)
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{
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Node& node = tcx.LocateNode(point);
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@ -205,11 +196,6 @@ Node& Sweep::NewFrontTriangle(SweepContext& tcx, Point& point, Node& node)
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return *new_node;
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}
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/**
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* Adds a triangle to the advancing front to fill a hole.
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* @param tcx
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* @param node - middle node, that is the bottom of the hole
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*/
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void Sweep::Fill(SweepContext& tcx, Node& node)
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{
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Triangle* triangle = new Triangle(*node.prev->point, *node.point, *node.next->point);
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@ -232,13 +218,6 @@ void Sweep::Fill(SweepContext& tcx, Node& node)
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}
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/**
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* Fills holes in the Advancing Front
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*
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*
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* @param tcx
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* @param n
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*/
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void Sweep::FillAdvancingFront(SweepContext& tcx, Node& n)
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{
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@ -278,11 +257,6 @@ double Sweep::BasinAngle(Node& node)
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return atan2(ay, ax);
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}
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/**
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*
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* @param node - middle node
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* @return the angle between 3 front nodes
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*/
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double Sweep::HoleAngle(Node& node)
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{
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/* Complex plane
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@ -300,9 +274,6 @@ double Sweep::HoleAngle(Node& node)
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return atan2(ax * by - ay * bx, ax * bx + ay * by);
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}
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/**
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* Returns true if triangle was legalized
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*/
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bool Sweep::Legalize(SweepContext& tcx, Triangle& t)
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{
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// To legalize a triangle we start by finding if any of the three edges
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@ -364,30 +335,6 @@ bool Sweep::Legalize(SweepContext& tcx, Triangle& t)
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return false;
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}
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/**
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* <b>Requirement</b>:<br>
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* 1. a,b and c form a triangle.<br>
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* 2. a and d is know to be on opposite side of bc<br>
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* <pre>
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* a
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* +
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* / \
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* / \
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* b/ \c
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* +-------+
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* / d \
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* / \
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* </pre>
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* <b>Fact</b>: d has to be in area B to have a chance to be inside the circle formed by
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* a,b and c<br>
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* d is outside B if orient2d(a,b,d) or orient2d(c,a,d) is CW<br>
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* This preknowledge gives us a way to optimize the incircle test
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* @param a - triangle point, opposite d
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* @param b - triangle point
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* @param c - triangle point
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* @param d - point opposite a
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* @return true if d is inside circle, false if on circle edge
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*/
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bool Sweep::Incircle(Point& pa, Point& pb, Point& pc, Point& pd)
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{
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double adx = pa.x - pd.x;
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@ -424,20 +371,6 @@ bool Sweep::Incircle(Point& pa, Point& pb, Point& pc, Point& pd)
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return det > 0;
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}
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/**
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* Rotates a triangle pair one vertex CW
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*<pre>
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* n2 n2
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* P +-----+ P +-----+
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* | t /| |\ t |
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* | / | | \ |
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* n1| / |n3 n1| \ |n3
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* | / | after CW | \ |
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* |/ oT | | oT \|
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* +-----+ oP +-----+
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* n4 n4
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* </pre>
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*/
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void Sweep::RotateTrianglePair(Triangle& t, Point& p, Triangle& ot, Point& op)
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{
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Triangle* n1, *n2, *n3, *n4;
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@ -487,15 +420,6 @@ void Sweep::RotateTrianglePair(Triangle& t, Point& p, Triangle& ot, Point& op)
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t.MarkNeighbor(ot);
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}
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/**
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* Fills a basin that has formed on the Advancing Front to the right
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* of given node.<br>
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* First we decide a left,bottom and right node that forms the
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* boundaries of the basin. Then we do a reqursive fill.
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*
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* @param tcx
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* @param node - starting node, this or next node will be left node
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*/
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void Sweep::FillBasin(SweepContext& tcx, Node& node)
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{
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if (Orient2d(*node.point, *node.next->point, *node.next->next->point) == CCW) {
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@ -531,13 +455,6 @@ void Sweep::FillBasin(SweepContext& tcx, Node& node)
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FillBasinReq(tcx, tcx.basin.bottom_node);
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}
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/**
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* Recursive algorithm to fill a Basin with triangles
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*
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* @param tcx
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* @param node - bottom_node
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* @param cnt - counter used to alternate on even and odd numbers
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*/
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void Sweep::FillBasinReq(SweepContext& tcx, Node* node)
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{
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// if shallow stop filling
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@ -49,75 +49,227 @@ struct Point;
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struct Edge;
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class Triangle;
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class Sweep {
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class Sweep
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{
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public:
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void Triangulate(SweepContext& tcx);
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~Sweep();
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/**
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* Triangulate
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*
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* @param tcx
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*/
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void Triangulate(SweepContext& tcx);
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/**
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* Destructor - clean up memory
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*/
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~Sweep();
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private:
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void SweepPoints(SweepContext& tcx);
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/**
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* Start sweeping the Y-sorted point set from bottom to top
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*
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* @param tcx
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*/
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void SweepPoints(SweepContext& tcx);
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Node& PointEvent(SweepContext& tcx, Point& point);
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/**
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* Find closes node to the left of the new point and
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* create a new triangle. If needed new holes and basins
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* will be filled to.
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*
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* @param tcx
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* @param point
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* @return
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*/
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Node& PointEvent(SweepContext& tcx, Point& point);
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void EdgeEvent(SweepContext& tcx, Edge* edge, Node* node);
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/**
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*
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*
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* @param tcx
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* @param edge
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* @param node
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*/
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void EdgeEvent(SweepContext& tcx, Edge* edge, Node* node);
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void EdgeEvent(SweepContext& tcx, Point& ep, Point& eq, Triangle* triangle, Point& point);
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void EdgeEvent(SweepContext& tcx, Point& ep, Point& eq, Triangle* triangle, Point& point);
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Node& NewFrontTriangle(SweepContext& tcx, Point& point, Node& node);
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/**
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* Creates a new front triangle and legalize it
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*
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* @param tcx
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* @param point
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* @param node
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* @return
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*/
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Node& NewFrontTriangle(SweepContext& tcx, Point& point, Node& node);
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void Fill(SweepContext& tcx, Node& node);
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/**
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* Adds a triangle to the advancing front to fill a hole.
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* @param tcx
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* @param node - middle node, that is the bottom of the hole
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*/
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void Fill(SweepContext& tcx, Node& node);
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bool Legalize(SweepContext& tcx, Triangle& t);
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/**
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* Returns true if triangle was legalized
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*/
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bool Legalize(SweepContext& tcx, Triangle& t);
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bool Incircle(Point& pa, Point& pb, Point& pc, Point& pd);
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/**
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* <b>Requirement</b>:<br>
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* 1. a,b and c form a triangle.<br>
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* 2. a and d is know to be on opposite side of bc<br>
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* <pre>
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* a
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* +
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* / \
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* / \
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* b/ \c
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* +-------+
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* / d \
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* / \
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* </pre>
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* <b>Fact</b>: d has to be in area B to have a chance to be inside the circle formed by
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* a,b and c<br>
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* d is outside B if orient2d(a,b,d) or orient2d(c,a,d) is CW<br>
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* This preknowledge gives us a way to optimize the incircle test
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* @param a - triangle point, opposite d
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* @param b - triangle point
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* @param c - triangle point
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* @param d - point opposite a
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* @return true if d is inside circle, false if on circle edge
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*/
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bool Incircle(Point& pa, Point& pb, Point& pc, Point& pd);
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void RotateTrianglePair(Triangle& t, Point& p, Triangle& ot, Point& op);
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/**
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* Rotates a triangle pair one vertex CW
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*<pre>
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* n2 n2
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* P +-----+ P +-----+
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* | t /| |\ t |
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* | / | | \ |
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* n1| / |n3 n1| \ |n3
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* | / | after CW | \ |
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* |/ oT | | oT \|
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* +-----+ oP +-----+
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* n4 n4
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* </pre>
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*/
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void RotateTrianglePair(Triangle& t, Point& p, Triangle& ot, Point& op);
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void FillAdvancingFront(SweepContext& tcx, Node& n);
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/**
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* Fills holes in the Advancing Front
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*
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*
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* @param tcx
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* @param n
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*/
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void FillAdvancingFront(SweepContext& tcx, Node& n);
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double HoleAngle(Node& node);
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/**
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*
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* @param node - middle node
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* @return the angle between 3 front nodes
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*/
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double HoleAngle(Node& node);
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double BasinAngle(Node& node);
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/**
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* The basin angle is decided against the horizontal line [1,0]
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*/
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double BasinAngle(Node& node);
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void FillBasin(SweepContext& tcx, Node& node);
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/**
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* Fills a basin that has formed on the Advancing Front to the right
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* of given node.<br>
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* First we decide a left,bottom and right node that forms the
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* boundaries of the basin. Then we do a reqursive fill.
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*
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* @param tcx
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* @param node - starting node, this or next node will be left node
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*/
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void FillBasin(SweepContext& tcx, Node& node);
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void FillBasinReq(SweepContext& tcx, Node* node);
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/**
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* Recursive algorithm to fill a Basin with triangles
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*
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* @param tcx
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* @param node - bottom_node
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* @param cnt - counter used to alternate on even and odd numbers
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*/
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void FillBasinReq(SweepContext& tcx, Node* node);
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bool IsShallow(SweepContext& tcx, Node& node);
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bool IsShallow(SweepContext& tcx, Node& node);
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bool IsEdgeSideOfTriangle(Triangle& triangle, Point& ep, Point& eq);
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bool IsEdgeSideOfTriangle(Triangle& triangle, Point& ep, Point& eq);
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void FillEdgeEvent(SweepContext& tcx, Edge* edge, Node* node);
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void FillEdgeEvent(SweepContext& tcx, Edge* edge, Node* node);
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void FillRightAboveEdgeEvent(SweepContext& tcx, Edge* edge, Node* node);
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void FillRightAboveEdgeEvent(SweepContext& tcx, Edge* edge, Node* node);
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void FillRightBelowEdgeEvent(SweepContext& tcx, Edge* edge, Node& node);
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void FillRightBelowEdgeEvent(SweepContext& tcx, Edge* edge, Node& node);
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void FillRightConcaveEdgeEvent(SweepContext& tcx, Edge* edge, Node& node);
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void FillRightConcaveEdgeEvent(SweepContext& tcx, Edge* edge, Node& node);
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void FillRightConvexEdgeEvent(SweepContext& tcx, Edge* edge, Node& node);
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void FillRightConvexEdgeEvent(SweepContext& tcx, Edge* edge, Node& node);
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void FillLeftAboveEdgeEvent(SweepContext& tcx, Edge* edge, Node* node);
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void FillLeftAboveEdgeEvent(SweepContext& tcx, Edge* edge, Node* node);
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void FillLeftBelowEdgeEvent(SweepContext& tcx, Edge* edge, Node& node);
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void FillLeftBelowEdgeEvent(SweepContext& tcx, Edge* edge, Node& node);
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void FillLeftConcaveEdgeEvent(SweepContext& tcx, Edge* edge, Node& node);
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void FillLeftConcaveEdgeEvent(SweepContext& tcx, Edge* edge, Node& node);
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void FillLeftConvexEdgeEvent(SweepContext& tcx, Edge* edge, Node& node);
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void FillLeftConvexEdgeEvent(SweepContext& tcx, Edge* edge, Node& node);
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void FlipEdgeEvent(SweepContext& tcx, Point& ep, Point& eq, Triangle* t, Point& p);
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void FlipEdgeEvent(SweepContext& tcx, Point& ep, Point& eq, Triangle* t, Point& p);
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Triangle& NextFlipTriangle(SweepContext& tcx, int o, Triangle& t, Triangle& ot, Point& p, Point& op);
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/**
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* After a flip we have two triangles and know that only one will still be
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* intersecting the edge. So decide which to contiune with and legalize the other
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*
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* @param tcx
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* @param o - should be the result of an orient2d( eq, op, ep )
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* @param t - triangle 1
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* @param ot - triangle 2
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* @param p - a point shared by both triangles
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* @param op - another point shared by both triangles
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* @return returns the triangle still intersecting the edge
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*/
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Triangle& NextFlipTriangle(SweepContext& tcx, int o, Triangle& t, Triangle& ot, Point& p, Point& op);
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Point& NextFlipPoint(Point& ep, Point& eq, Triangle& ot, Point& op);
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/**
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* When we need to traverse from one triangle to the next we need
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* the point in current triangle that is the opposite point to the next
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* triangle.
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*
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* @param ep
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* @param eq
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* @param ot
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* @param op
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* @return
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*/
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Point& NextFlipPoint(Point& ep, Point& eq, Triangle& ot, Point& op);
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void FlipScanEdgeEvent(SweepContext& tcx, Point& ep, Point& eq, Triangle& flip_triangle, Triangle& t, Point& p);
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/**
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* Scan part of the FlipScan algorithm<br>
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* When a triangle pair isn't flippable we will scan for the next
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* point that is inside the flip triangle scan area. When found
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* we generate a new flipEdgeEvent
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*
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* @param tcx
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* @param ep - last point on the edge we are traversing
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* @param eq - first point on the edge we are traversing
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* @param flipTriangle - the current triangle sharing the point eq with edge
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* @param t
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* @param p
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*/
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||||
void FlipScanEdgeEvent(SweepContext& tcx, Point& ep, Point& eq, Triangle& flip_triangle, Triangle& t, Point& p);
|
||||
|
||||
void FinalizationPolygon(SweepContext& tcx);
|
||||
void FinalizationPolygon(SweepContext& tcx);
|
||||
|
||||
std::vector<Node*> nodes_;
|
||||
std::vector<Node*> nodes_;
|
||||
|
||||
};
|
||||
|
||||
|
|
|
|||
Loading…
Reference in New Issue