updated comments

This commit is contained in:
zzzzrrr 2011-03-08 11:06:09 -05:00
parent 9f1a0dff10
commit b5c5cbd82f
3 changed files with 239 additions and 134 deletions

View File

@ -36,31 +36,67 @@
#include "sweep_context.h"
#include "sweep.h"
/**
*
* @author Mason Green <mason.green@gmail.com>
*
*/
namespace p2t {
class CDT
{
public:
/// Constructor
CDT(std::vector<Point*> polyline);
/// Destructor
~CDT();
/// Add a hole
void AddHole(std::vector<Point*> polyline);
/// Add a single point
void AddPoint(Point* point);
/// Triangulate points
void Triangulate();
/// Get Delaunay triangles
std::vector<Triangle*> GetTriangles();
/// Get triangle map
std::list<Triangle*> GetMap();
/**
* Constructor - add polyline with non repeating points
*
* @param polyline
*/
CDT(std::vector<Point*> polyline);
private:
/**
* Destructor - clean up memory
*/
~CDT();
SweepContext* sweep_context_;
Sweep* sweep_;
/**
* Add a hole
*
* @param polyline
*/
void AddHole(std::vector<Point*> polyline);
/**
* Add a steiner point
*
* @param point
*/
void AddPoint(Point* point);
/**
* Triangulate - do this AFTER you've added the polyline, holes, and Steiner points
*/
void Triangulate();
/**
* Get CDT triangles
*/
std::vector<Triangle*> GetTriangles();
/**
* Get triangle map
*/
std::list<Triangle*> GetMap();
private:
/**
* Internals
*/
SweepContext* sweep_context_;
Sweep* sweep_;
};

View File

@ -71,15 +71,6 @@ void Sweep::FinalizationPolygon(SweepContext& tcx)
tcx.MeshClean(*t);
}
/**
* Find closes node to the left of the new point and
* create a new triangle. If needed new holes and basins
* will be filled to.
*
* @param tcx
* @param point
* @return
*/
Node& Sweep::PointEvent(SweepContext& tcx, Point& point)
{
Node& node = tcx.LocateNode(point);
@ -205,11 +196,6 @@ Node& Sweep::NewFrontTriangle(SweepContext& tcx, Point& point, Node& node)
return *new_node;
}
/**
* Adds a triangle to the advancing front to fill a hole.
* @param tcx
* @param node - middle node, that is the bottom of the hole
*/
void Sweep::Fill(SweepContext& tcx, Node& node)
{
Triangle* triangle = new Triangle(*node.prev->point, *node.point, *node.next->point);
@ -232,13 +218,6 @@ void Sweep::Fill(SweepContext& tcx, Node& node)
}
/**
* Fills holes in the Advancing Front
*
*
* @param tcx
* @param n
*/
void Sweep::FillAdvancingFront(SweepContext& tcx, Node& n)
{
@ -278,11 +257,6 @@ double Sweep::BasinAngle(Node& node)
return atan2(ay, ax);
}
/**
*
* @param node - middle node
* @return the angle between 3 front nodes
*/
double Sweep::HoleAngle(Node& node)
{
/* Complex plane
@ -300,9 +274,6 @@ double Sweep::HoleAngle(Node& node)
return atan2(ax * by - ay * bx, ax * bx + ay * by);
}
/**
* Returns true if triangle was legalized
*/
bool Sweep::Legalize(SweepContext& tcx, Triangle& t)
{
// To legalize a triangle we start by finding if any of the three edges
@ -364,30 +335,6 @@ bool Sweep::Legalize(SweepContext& tcx, Triangle& t)
return false;
}
/**
* <b>Requirement</b>:<br>
* 1. a,b and c form a triangle.<br>
* 2. a and d is know to be on opposite side of bc<br>
* <pre>
* a
* +
* / \
* / \
* b/ \c
* +-------+
* / d \
* / \
* </pre>
* <b>Fact</b>: d has to be in area B to have a chance to be inside the circle formed by
* a,b and c<br>
* d is outside B if orient2d(a,b,d) or orient2d(c,a,d) is CW<br>
* This preknowledge gives us a way to optimize the incircle test
* @param a - triangle point, opposite d
* @param b - triangle point
* @param c - triangle point
* @param d - point opposite a
* @return true if d is inside circle, false if on circle edge
*/
bool Sweep::Incircle(Point& pa, Point& pb, Point& pc, Point& pd)
{
double adx = pa.x - pd.x;
@ -424,20 +371,6 @@ bool Sweep::Incircle(Point& pa, Point& pb, Point& pc, Point& pd)
return det > 0;
}
/**
* Rotates a triangle pair one vertex CW
*<pre>
* n2 n2
* P +-----+ P +-----+
* | t /| |\ t |
* | / | | \ |
* n1| / |n3 n1| \ |n3
* | / | after CW | \ |
* |/ oT | | oT \|
* +-----+ oP +-----+
* n4 n4
* </pre>
*/
void Sweep::RotateTrianglePair(Triangle& t, Point& p, Triangle& ot, Point& op)
{
Triangle* n1, *n2, *n3, *n4;
@ -487,15 +420,6 @@ void Sweep::RotateTrianglePair(Triangle& t, Point& p, Triangle& ot, Point& op)
t.MarkNeighbor(ot);
}
/**
* Fills a basin that has formed on the Advancing Front to the right
* of given node.<br>
* First we decide a left,bottom and right node that forms the
* boundaries of the basin. Then we do a reqursive fill.
*
* @param tcx
* @param node - starting node, this or next node will be left node
*/
void Sweep::FillBasin(SweepContext& tcx, Node& node)
{
if (Orient2d(*node.point, *node.next->point, *node.next->next->point) == CCW) {
@ -531,13 +455,6 @@ void Sweep::FillBasin(SweepContext& tcx, Node& node)
FillBasinReq(tcx, tcx.basin.bottom_node);
}
/**
* Recursive algorithm to fill a Basin with triangles
*
* @param tcx
* @param node - bottom_node
* @param cnt - counter used to alternate on even and odd numbers
*/
void Sweep::FillBasinReq(SweepContext& tcx, Node* node)
{
// if shallow stop filling

View File

@ -49,75 +49,227 @@ struct Point;
struct Edge;
class Triangle;
class Sweep {
class Sweep
{
public:
void Triangulate(SweepContext& tcx);
~Sweep();
/**
* Triangulate
*
* @param tcx
*/
void Triangulate(SweepContext& tcx);
/**
* Destructor - clean up memory
*/
~Sweep();
private:
void SweepPoints(SweepContext& tcx);
/**
* Start sweeping the Y-sorted point set from bottom to top
*
* @param tcx
*/
void SweepPoints(SweepContext& tcx);
Node& PointEvent(SweepContext& tcx, Point& point);
/**
* Find closes node to the left of the new point and
* create a new triangle. If needed new holes and basins
* will be filled to.
*
* @param tcx
* @param point
* @return
*/
Node& PointEvent(SweepContext& tcx, Point& point);
void EdgeEvent(SweepContext& tcx, Edge* edge, Node* node);
/**
*
*
* @param tcx
* @param edge
* @param node
*/
void EdgeEvent(SweepContext& tcx, Edge* edge, Node* node);
void EdgeEvent(SweepContext& tcx, Point& ep, Point& eq, Triangle* triangle, Point& point);
void EdgeEvent(SweepContext& tcx, Point& ep, Point& eq, Triangle* triangle, Point& point);
Node& NewFrontTriangle(SweepContext& tcx, Point& point, Node& node);
/**
* Creates a new front triangle and legalize it
*
* @param tcx
* @param point
* @param node
* @return
*/
Node& NewFrontTriangle(SweepContext& tcx, Point& point, Node& node);
void Fill(SweepContext& tcx, Node& node);
/**
* Adds a triangle to the advancing front to fill a hole.
* @param tcx
* @param node - middle node, that is the bottom of the hole
*/
void Fill(SweepContext& tcx, Node& node);
bool Legalize(SweepContext& tcx, Triangle& t);
/**
* Returns true if triangle was legalized
*/
bool Legalize(SweepContext& tcx, Triangle& t);
bool Incircle(Point& pa, Point& pb, Point& pc, Point& pd);
/**
* <b>Requirement</b>:<br>
* 1. a,b and c form a triangle.<br>
* 2. a and d is know to be on opposite side of bc<br>
* <pre>
* a
* +
* / \
* / \
* b/ \c
* +-------+
* / d \
* / \
* </pre>
* <b>Fact</b>: d has to be in area B to have a chance to be inside the circle formed by
* a,b and c<br>
* d is outside B if orient2d(a,b,d) or orient2d(c,a,d) is CW<br>
* This preknowledge gives us a way to optimize the incircle test
* @param a - triangle point, opposite d
* @param b - triangle point
* @param c - triangle point
* @param d - point opposite a
* @return true if d is inside circle, false if on circle edge
*/
bool Incircle(Point& pa, Point& pb, Point& pc, Point& pd);
void RotateTrianglePair(Triangle& t, Point& p, Triangle& ot, Point& op);
/**
* Rotates a triangle pair one vertex CW
*<pre>
* n2 n2
* P +-----+ P +-----+
* | t /| |\ t |
* | / | | \ |
* n1| / |n3 n1| \ |n3
* | / | after CW | \ |
* |/ oT | | oT \|
* +-----+ oP +-----+
* n4 n4
* </pre>
*/
void RotateTrianglePair(Triangle& t, Point& p, Triangle& ot, Point& op);
void FillAdvancingFront(SweepContext& tcx, Node& n);
/**
* Fills holes in the Advancing Front
*
*
* @param tcx
* @param n
*/
void FillAdvancingFront(SweepContext& tcx, Node& n);
double HoleAngle(Node& node);
/**
*
* @param node - middle node
* @return the angle between 3 front nodes
*/
double HoleAngle(Node& node);
double BasinAngle(Node& node);
/**
* The basin angle is decided against the horizontal line [1,0]
*/
double BasinAngle(Node& node);
void FillBasin(SweepContext& tcx, Node& node);
/**
* Fills a basin that has formed on the Advancing Front to the right
* of given node.<br>
* First we decide a left,bottom and right node that forms the
* boundaries of the basin. Then we do a reqursive fill.
*
* @param tcx
* @param node - starting node, this or next node will be left node
*/
void FillBasin(SweepContext& tcx, Node& node);
void FillBasinReq(SweepContext& tcx, Node* node);
/**
* Recursive algorithm to fill a Basin with triangles
*
* @param tcx
* @param node - bottom_node
* @param cnt - counter used to alternate on even and odd numbers
*/
void FillBasinReq(SweepContext& tcx, Node* node);
bool IsShallow(SweepContext& tcx, Node& node);
bool IsShallow(SweepContext& tcx, Node& node);
bool IsEdgeSideOfTriangle(Triangle& triangle, Point& ep, Point& eq);
bool IsEdgeSideOfTriangle(Triangle& triangle, Point& ep, Point& eq);
void FillEdgeEvent(SweepContext& tcx, Edge* edge, Node* node);
void FillEdgeEvent(SweepContext& tcx, Edge* edge, Node* node);
void FillRightAboveEdgeEvent(SweepContext& tcx, Edge* edge, Node* node);
void FillRightAboveEdgeEvent(SweepContext& tcx, Edge* edge, Node* node);
void FillRightBelowEdgeEvent(SweepContext& tcx, Edge* edge, Node& node);
void FillRightBelowEdgeEvent(SweepContext& tcx, Edge* edge, Node& node);
void FillRightConcaveEdgeEvent(SweepContext& tcx, Edge* edge, Node& node);
void FillRightConcaveEdgeEvent(SweepContext& tcx, Edge* edge, Node& node);
void FillRightConvexEdgeEvent(SweepContext& tcx, Edge* edge, Node& node);
void FillRightConvexEdgeEvent(SweepContext& tcx, Edge* edge, Node& node);
void FillLeftAboveEdgeEvent(SweepContext& tcx, Edge* edge, Node* node);
void FillLeftAboveEdgeEvent(SweepContext& tcx, Edge* edge, Node* node);
void FillLeftBelowEdgeEvent(SweepContext& tcx, Edge* edge, Node& node);
void FillLeftBelowEdgeEvent(SweepContext& tcx, Edge* edge, Node& node);
void FillLeftConcaveEdgeEvent(SweepContext& tcx, Edge* edge, Node& node);
void FillLeftConcaveEdgeEvent(SweepContext& tcx, Edge* edge, Node& node);
void FillLeftConvexEdgeEvent(SweepContext& tcx, Edge* edge, Node& node);
void FillLeftConvexEdgeEvent(SweepContext& tcx, Edge* edge, Node& node);
void FlipEdgeEvent(SweepContext& tcx, Point& ep, Point& eq, Triangle* t, Point& p);
void FlipEdgeEvent(SweepContext& tcx, Point& ep, Point& eq, Triangle* t, Point& p);
Triangle& NextFlipTriangle(SweepContext& tcx, int o, Triangle& t, Triangle& ot, Point& p, Point& op);
/**
* After a flip we have two triangles and know that only one will still be
* intersecting the edge. So decide which to contiune with and legalize the other
*
* @param tcx
* @param o - should be the result of an orient2d( eq, op, ep )
* @param t - triangle 1
* @param ot - triangle 2
* @param p - a point shared by both triangles
* @param op - another point shared by both triangles
* @return returns the triangle still intersecting the edge
*/
Triangle& NextFlipTriangle(SweepContext& tcx, int o, Triangle& t, Triangle& ot, Point& p, Point& op);
Point& NextFlipPoint(Point& ep, Point& eq, Triangle& ot, Point& op);
/**
* When we need to traverse from one triangle to the next we need
* the point in current triangle that is the opposite point to the next
* triangle.
*
* @param ep
* @param eq
* @param ot
* @param op
* @return
*/
Point& NextFlipPoint(Point& ep, Point& eq, Triangle& ot, Point& op);
void FlipScanEdgeEvent(SweepContext& tcx, Point& ep, Point& eq, Triangle& flip_triangle, Triangle& t, Point& p);
/**
* Scan part of the FlipScan algorithm<br>
* When a triangle pair isn't flippable we will scan for the next
* point that is inside the flip triangle scan area. When found
* we generate a new flipEdgeEvent
*
* @param tcx
* @param ep - last point on the edge we are traversing
* @param eq - first point on the edge we are traversing
* @param flipTriangle - the current triangle sharing the point eq with edge
* @param t
* @param p
*/
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_;
};