Model loading and texturing

This commit is contained in:
Dane Johnson
2021-01-18 18:25:47 -06:00
parent 66bf7776c7
commit 155b572aca
1283 changed files with 533814 additions and 42 deletions

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Primary Contributors:
Mason Green <mason.green@gmail.com> (C++, Python)
Thomas Åhlén <thahlen@gmail.com> (Java)
Other Contributors:

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Poly2Tri Copyright (c) 2009-2010, Poly2Tri Contributors
http://code.google.com/p/poly2tri/
All rights reserved.
Redistribution and use in source and binary forms, with or without modification,
are permitted provided that the following conditions are met:
* Redistributions of source code must retain the above copyright notice,
this list of conditions and the following disclaimer.
* Redistributions in binary form must reproduce the above copyright notice,
this list of conditions and the following disclaimer in the documentation
and/or other materials provided with the distribution.
* Neither the name of Poly2Tri nor the names of its contributors may be
used to endorse or promote products derived from this software without specific
prior written permission.
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

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==================
INSTALLATION GUIDE
==================
------------
Dependencies
------------
Core poly2tri lib:
- Standard Template Library (STL)
Testbed:
- gcc
- OpenGL
- GLFW (http://glfw.sf.net)
- Python
Waf (http://code.google.com/p/waf/) is used to compile the testbed.
A waf script (86kb) is included in the repositoty.
----------------------------------------------
Building the Testbed
----------------------------------------------
Posix/MSYS environment:
./waf configure
./waf build
Windows command line:
python waf configure
python waf build
----------------------------------------------
Running the Examples
----------------------------------------------
Load data points from a file:
p2t <filename> <center_x> <center_y> <zoom>
Random distribution of points inside a consrained box:
p2t random <num_points> <box_radius> <zoom>
Examples:
./p2t dude.dat 300 500 2
./p2t nazca_monkey.dat 0 0 9
./p2t random 10 100 5.0
./p2t random 1000 20000 0.025

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/*
* Poly2Tri Copyright (c) 2009-2010, Poly2Tri Contributors
* http://code.google.com/p/poly2tri/
*
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without modification,
* are permitted provided that the following conditions are met:
*
* * Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
* * Neither the name of Poly2Tri nor the names of its contributors may be
* used to endorse or promote products derived from this software without specific
* prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include "shapes.h"
#include <iostream>
namespace p2t {
Triangle::Triangle(Point& a, Point& b, Point& c)
{
points_[0] = &a; points_[1] = &b; points_[2] = &c;
neighbors_[0] = NULL; neighbors_[1] = NULL; neighbors_[2] = NULL;
constrained_edge[0] = constrained_edge[1] = constrained_edge[2] = false;
delaunay_edge[0] = delaunay_edge[1] = delaunay_edge[2] = false;
interior_ = false;
}
// Update neighbor pointers
void Triangle::MarkNeighbor(Point* p1, Point* p2, Triangle* t)
{
if ((p1 == points_[2] && p2 == points_[1]) || (p1 == points_[1] && p2 == points_[2]))
neighbors_[0] = t;
else if ((p1 == points_[0] && p2 == points_[2]) || (p1 == points_[2] && p2 == points_[0]))
neighbors_[1] = t;
else if ((p1 == points_[0] && p2 == points_[1]) || (p1 == points_[1] && p2 == points_[0]))
neighbors_[2] = t;
else
assert(0);
}
// Exhaustive search to update neighbor pointers
void Triangle::MarkNeighbor(Triangle& t)
{
if (t.Contains(points_[1], points_[2])) {
neighbors_[0] = &t;
t.MarkNeighbor(points_[1], points_[2], this);
} else if (t.Contains(points_[0], points_[2])) {
neighbors_[1] = &t;
t.MarkNeighbor(points_[0], points_[2], this);
} else if (t.Contains(points_[0], points_[1])) {
neighbors_[2] = &t;
t.MarkNeighbor(points_[0], points_[1], this);
}
}
/**
* Clears all references to all other triangles and points
*/
void Triangle::Clear()
{
Triangle *t;
for( int i=0; i<3; i++ )
{
t = neighbors_[i];
if( t != NULL )
{
t->ClearNeighbor( this );
}
}
ClearNeighbors();
points_[0]=points_[1]=points_[2] = NULL;
}
void Triangle::ClearNeighbor(const Triangle *triangle )
{
if( neighbors_[0] == triangle )
{
neighbors_[0] = NULL;
}
else if( neighbors_[1] == triangle )
{
neighbors_[1] = NULL;
}
else
{
neighbors_[2] = NULL;
}
}
void Triangle::ClearNeighbors()
{
neighbors_[0] = NULL;
neighbors_[1] = NULL;
neighbors_[2] = NULL;
}
void Triangle::ClearDelunayEdges()
{
delaunay_edge[0] = delaunay_edge[1] = delaunay_edge[2] = false;
}
Point* Triangle::OppositePoint(Triangle& t, const Point& p)
{
Point *cw = t.PointCW(p);
return PointCW(*cw);
}
// Legalized triangle by rotating clockwise around point(0)
void Triangle::Legalize(Point& point)
{
points_[1] = points_[0];
points_[0] = points_[2];
points_[2] = &point;
}
// Legalize triagnle by rotating clockwise around oPoint
void Triangle::Legalize(Point& opoint, Point& npoint)
{
if (&opoint == points_[0]) {
points_[1] = points_[0];
points_[0] = points_[2];
points_[2] = &npoint;
} else if (&opoint == points_[1]) {
points_[2] = points_[1];
points_[1] = points_[0];
points_[0] = &npoint;
} else if (&opoint == points_[2]) {
points_[0] = points_[2];
points_[2] = points_[1];
points_[1] = &npoint;
} else {
assert(0);
}
}
int Triangle::Index(const Point* p)
{
if (p == points_[0]) {
return 0;
} else if (p == points_[1]) {
return 1;
} else if (p == points_[2]) {
return 2;
}
assert(0);
return -1;
}
int Triangle::EdgeIndex(const Point* p1, const Point* p2)
{
if (points_[0] == p1) {
if (points_[1] == p2) {
return 2;
} else if (points_[2] == p2) {
return 1;
}
} else if (points_[1] == p1) {
if (points_[2] == p2) {
return 0;
} else if (points_[0] == p2) {
return 2;
}
} else if (points_[2] == p1) {
if (points_[0] == p2) {
return 1;
} else if (points_[1] == p2) {
return 0;
}
}
return -1;
}
void Triangle::MarkConstrainedEdge(int index)
{
constrained_edge[index] = true;
}
void Triangle::MarkConstrainedEdge(Edge& edge)
{
MarkConstrainedEdge(edge.p, edge.q);
}
// Mark edge as constrained
void Triangle::MarkConstrainedEdge(Point* p, Point* q)
{
if ((q == points_[0] && p == points_[1]) || (q == points_[1] && p == points_[0])) {
constrained_edge[2] = true;
} else if ((q == points_[0] && p == points_[2]) || (q == points_[2] && p == points_[0])) {
constrained_edge[1] = true;
} else if ((q == points_[1] && p == points_[2]) || (q == points_[2] && p == points_[1])) {
constrained_edge[0] = true;
}
}
// The point counter-clockwise to given point
Point* Triangle::PointCW(const Point& point)
{
if (&point == points_[0]) {
return points_[2];
} else if (&point == points_[1]) {
return points_[0];
} else if (&point == points_[2]) {
return points_[1];
}
assert(0);
return NULL;
}
// The point counter-clockwise to given point
Point* Triangle::PointCCW(const Point& point)
{
if (&point == points_[0]) {
return points_[1];
} else if (&point == points_[1]) {
return points_[2];
} else if (&point == points_[2]) {
return points_[0];
}
assert(0);
return NULL;
}
// The neighbor clockwise to given point
Triangle* Triangle::NeighborCW(const Point& point)
{
if (&point == points_[0]) {
return neighbors_[1];
} else if (&point == points_[1]) {
return neighbors_[2];
}
return neighbors_[0];
}
// The neighbor counter-clockwise to given point
Triangle* Triangle::NeighborCCW(const Point& point)
{
if (&point == points_[0]) {
return neighbors_[2];
} else if (&point == points_[1]) {
return neighbors_[0];
}
return neighbors_[1];
}
bool Triangle::GetConstrainedEdgeCCW(const Point& p)
{
if (&p == points_[0]) {
return constrained_edge[2];
} else if (&p == points_[1]) {
return constrained_edge[0];
}
return constrained_edge[1];
}
bool Triangle::GetConstrainedEdgeCW(const Point& p)
{
if (&p == points_[0]) {
return constrained_edge[1];
} else if (&p == points_[1]) {
return constrained_edge[2];
}
return constrained_edge[0];
}
void Triangle::SetConstrainedEdgeCCW(const Point& p, bool ce)
{
if (&p == points_[0]) {
constrained_edge[2] = ce;
} else if (&p == points_[1]) {
constrained_edge[0] = ce;
} else {
constrained_edge[1] = ce;
}
}
void Triangle::SetConstrainedEdgeCW(const Point& p, bool ce)
{
if (&p == points_[0]) {
constrained_edge[1] = ce;
} else if (&p == points_[1]) {
constrained_edge[2] = ce;
} else {
constrained_edge[0] = ce;
}
}
bool Triangle::GetDelunayEdgeCCW(const Point& p)
{
if (&p == points_[0]) {
return delaunay_edge[2];
} else if (&p == points_[1]) {
return delaunay_edge[0];
}
return delaunay_edge[1];
}
bool Triangle::GetDelunayEdgeCW(const Point& p)
{
if (&p == points_[0]) {
return delaunay_edge[1];
} else if (&p == points_[1]) {
return delaunay_edge[2];
}
return delaunay_edge[0];
}
void Triangle::SetDelunayEdgeCCW(const Point& p, bool e)
{
if (&p == points_[0]) {
delaunay_edge[2] = e;
} else if (&p == points_[1]) {
delaunay_edge[0] = e;
} else {
delaunay_edge[1] = e;
}
}
void Triangle::SetDelunayEdgeCW(const Point& p, bool e)
{
if (&p == points_[0]) {
delaunay_edge[1] = e;
} else if (&p == points_[1]) {
delaunay_edge[2] = e;
} else {
delaunay_edge[0] = e;
}
}
// The neighbor across to given point
Triangle& Triangle::NeighborAcross(const Point& opoint)
{
if (&opoint == points_[0]) {
return *neighbors_[0];
} else if (&opoint == points_[1]) {
return *neighbors_[1];
}
return *neighbors_[2];
}
void Triangle::DebugPrint()
{
using namespace std;
cout << points_[0]->x << "," << points_[0]->y << " ";
cout << points_[1]->x << "," << points_[1]->y << " ";
cout << points_[2]->x << "," << points_[2]->y << endl;
}
}

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/*
* Poly2Tri Copyright (c) 2009-2010, Poly2Tri Contributors
* http://code.google.com/p/poly2tri/
*
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without modification,
* are permitted provided that the following conditions are met:
*
* * Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
* * Neither the name of Poly2Tri nor the names of its contributors may be
* used to endorse or promote products derived from this software without specific
* prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
// Include guard
#ifndef SHAPES_H
#define SHAPES_H
#include <vector>
#include <cstddef>
#include <stdexcept>
#include <assert.h>
#include <cmath>
#include <string>
namespace p2t {
struct Edge;
struct Point {
double x, y;
/// Default constructor does nothing (for performance).
Point()
{
x = 0.0;
y = 0.0;
}
/// The edges this point constitutes an upper ending point
std::vector<Edge*> edge_list;
/// Construct using coordinates.
Point(double x, double y) : x(x), y(y) {}
/// Set this point to all zeros.
void set_zero()
{
x = 0.0;
y = 0.0;
}
/// Set this point to some specified coordinates.
void set(double x_, double y_)
{
x = x_;
y = y_;
}
/// Negate this point.
Point operator -() const
{
Point v;
v.set(-x, -y);
return v;
}
/// Add a point to this point.
void operator +=(const Point& v)
{
x += v.x;
y += v.y;
}
/// Subtract a point from this point.
void operator -=(const Point& v)
{
x -= v.x;
y -= v.y;
}
/// Multiply this point by a scalar.
void operator *=(double a)
{
x *= a;
y *= a;
}
/// Get the length of this point (the norm).
double Length() const
{
return sqrt(x * x + y * y);
}
/// Convert this point into a unit point. Returns the Length.
double Normalize()
{
const double len = Length();
x /= len;
y /= len;
return len;
}
};
// Represents a simple polygon's edge
struct Edge {
Point* p, *q;
/// Constructor
Edge(Point& p1, Point& p2) : p(&p1), q(&p2)
{
if (p1.y > p2.y) {
q = &p1;
p = &p2;
} else if (p1.y == p2.y) {
if (p1.x > p2.x) {
q = &p1;
p = &p2;
} else if (p1.x == p2.x) {
// Repeat points
// ASSIMP_CHANGE (aramis_acg)
throw std::runtime_error(std::string("repeat points"));
//assert(false);
}
}
q->edge_list.push_back(this);
}
};
// Triangle-based data structures are know to have better performance than quad-edge structures
// See: J. Shewchuk, "Triangle: Engineering a 2D Quality Mesh Generator and Delaunay Triangulator"
// "Triangulations in CGAL"
class Triangle {
public:
/// Constructor
Triangle(Point& a, Point& b, Point& c);
/// Flags to determine if an edge is a Constrained edge
bool constrained_edge[3];
/// Flags to determine if an edge is a Delauney edge
bool delaunay_edge[3];
Point* GetPoint(int index);
Point* PointCW(const Point& point);
Point* PointCCW(const Point& point);
Point* OppositePoint(Triangle& t, const Point& p);
Triangle* GetNeighbor(int index);
void MarkNeighbor(Point* p1, Point* p2, Triangle* t);
void MarkNeighbor(Triangle& t);
void MarkConstrainedEdge(int index);
void MarkConstrainedEdge(Edge& edge);
void MarkConstrainedEdge(Point* p, Point* q);
int Index(const Point* p);
int EdgeIndex(const Point* p1, const Point* p2);
Triangle* NeighborCW(const Point& point);
Triangle* NeighborCCW(const Point& point);
bool GetConstrainedEdgeCCW(const Point& p);
bool GetConstrainedEdgeCW(const Point& p);
void SetConstrainedEdgeCCW(const Point& p, bool ce);
void SetConstrainedEdgeCW(const Point& p, bool ce);
bool GetDelunayEdgeCCW(const Point& p);
bool GetDelunayEdgeCW(const Point& p);
void SetDelunayEdgeCCW(const Point& p, bool e);
void SetDelunayEdgeCW(const Point& p, bool e);
bool Contains(const Point* p);
bool Contains(const Edge& e);
bool Contains(const Point* p, const Point* q);
void Legalize(Point& point);
void Legalize(Point& opoint, Point& npoint);
/**
* Clears all references to all other triangles and points
*/
void Clear();
void ClearNeighbor(const Triangle *triangle);
void ClearNeighbors();
void ClearDelunayEdges();
inline bool IsInterior();
inline void IsInterior(bool b);
Triangle& NeighborAcross(const Point& opoint);
void DebugPrint();
private:
/// Triangle points
Point* points_[3];
/// Neighbor list
Triangle* neighbors_[3];
/// Has this triangle been marked as an interior triangle?
bool interior_;
};
inline bool cmp(const Point* a, const Point* b)
{
if (a->y < b->y) {
return true;
} else if (a->y == b->y) {
// Make sure q is point with greater x value
if (a->x < b->x) {
return true;
}
}
return false;
}
/// Add two points_ component-wise.
inline Point operator +(const Point& a, const Point& b)
{
return Point(a.x + b.x, a.y + b.y);
}
/// Subtract two points_ component-wise.
inline Point operator -(const Point& a, const Point& b)
{
return Point(a.x - b.x, a.y - b.y);
}
/// Multiply point by scalar
inline Point operator *(double s, const Point& a)
{
return Point(s * a.x, s * a.y);
}
inline bool operator ==(const Point& a, const Point& b)
{
return a.x == b.x && a.y == b.y;
}
inline bool operator !=(const Point& a, const Point& b)
{
return !(a.x == b.x) && !(a.y == b.y);
}
/// Peform the dot product on two vectors.
inline double Dot(const Point& a, const Point& b)
{
return a.x * b.x + a.y * b.y;
}
/// Perform the cross product on two vectors. In 2D this produces a scalar.
inline double Cross(const Point& a, const Point& b)
{
return a.x * b.y - a.y * b.x;
}
/// Perform the cross product on a point and a scalar. In 2D this produces
/// a point.
inline Point Cross(const Point& a, double s)
{
return Point(s * a.y, -s * a.x);
}
/// Perform the cross product on a scalar and a point. In 2D this produces
/// a point.
inline Point Cross(double s, const Point& a)
{
return Point(-s * a.y, s * a.x);
}
inline Point* Triangle::GetPoint(int index)
{
return points_[index];
}
inline Triangle* Triangle::GetNeighbor(int index)
{
return neighbors_[index];
}
inline bool Triangle::Contains(const Point* p)
{
return p == points_[0] || p == points_[1] || p == points_[2];
}
inline bool Triangle::Contains(const Edge& e)
{
return Contains(e.p) && Contains(e.q);
}
inline bool Triangle::Contains(const Point* p, const Point* q)
{
return Contains(p) && Contains(q);
}
inline bool Triangle::IsInterior()
{
return interior_;
}
inline void Triangle::IsInterior(bool b)
{
interior_ = b;
}
}
#endif

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/*
* Poly2Tri Copyright (c) 2009-2010, Poly2Tri Contributors
* http://code.google.com/p/poly2tri/
*
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without modification,
* are permitted provided that the following conditions are met:
*
* * Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
* * Neither the name of Poly2Tri nor the names of its contributors may be
* used to endorse or promote products derived from this software without specific
* prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef UTILS_H
#define UTILS_H
// Otherwise #defines like M_PI are undeclared under Visual Studio
#define _USE_MATH_DEFINES
#include <exception>
#include <math.h>
// C99 removes M_PI from math.h
#ifndef M_PI
#define M_PI 3.14159265358979323846264338327
#endif
namespace p2t {
const double PI_3div4 = 3 * M_PI / 4;
const double PI_div2 = 1.57079632679489661923;
const double EPSILON = 1e-12;
enum Orientation { CW, CCW, COLLINEAR };
/**
* Forumla to calculate signed area<br>
* Positive if CCW<br>
* Negative if CW<br>
* 0 if collinear<br>
* <pre>
* A[P1,P2,P3] = (x1*y2 - y1*x2) + (x2*y3 - y2*x3) + (x3*y1 - y3*x1)
* = (x1-x3)*(y2-y3) - (y1-y3)*(x2-x3)
* </pre>
*/
Orientation Orient2d(const Point& pa, const Point& pb, const Point& pc)
{
double detleft = (pa.x - pc.x) * (pb.y - pc.y);
double detright = (pa.y - pc.y) * (pb.x - pc.x);
double val = detleft - detright;
if (val > -EPSILON && val < EPSILON) {
return COLLINEAR;
} else if (val > 0) {
return CCW;
}
return CW;
}
/*
bool InScanArea(Point& pa, Point& pb, Point& pc, Point& pd)
{
double pdx = pd.x;
double pdy = pd.y;
double adx = pa.x - pdx;
double ady = pa.y - pdy;
double bdx = pb.x - pdx;
double bdy = pb.y - pdy;
double adxbdy = adx * bdy;
double bdxady = bdx * ady;
double oabd = adxbdy - bdxady;
if (oabd <= EPSILON) {
return false;
}
double cdx = pc.x - pdx;
double cdy = pc.y - pdy;
double cdxady = cdx * ady;
double adxcdy = adx * cdy;
double ocad = cdxady - adxcdy;
if (ocad <= EPSILON) {
return false;
}
return true;
}
*/
bool InScanArea(const Point& pa, const Point& pb, const Point& pc, const Point& pd)
{
double oadb = (pa.x - pb.x)*(pd.y - pb.y) - (pd.x - pb.x)*(pa.y - pb.y);
if (oadb >= -EPSILON) {
return false;
}
double oadc = (pa.x - pc.x)*(pd.y - pc.y) - (pd.x - pc.x)*(pa.y - pc.y);
if (oadc <= EPSILON) {
return false;
}
return true;
}
}
#endif

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/*
* Poly2Tri Copyright (c) 2009-2010, Poly2Tri Contributors
* http://code.google.com/p/poly2tri/
*
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without modification,
* are permitted provided that the following conditions are met:
*
* * Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
* * Neither the name of Poly2Tri nor the names of its contributors may be
* used to endorse or promote products derived from this software without specific
* prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef POLY2TRI_H
#define POLY2TRI_H
#include "common/shapes.h"
#include "sweep/cdt.h"
#endif

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

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/*
* Poly2Tri Copyright (c) 2009-2010, Poly2Tri Contributors
* http://code.google.com/p/poly2tri/
*
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without modification,
* are permitted provided that the following conditions are met:
*
* * Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
* * Neither the name of Poly2Tri nor the names of its contributors may be
* used to endorse or promote products derived from this software without specific
* prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef ADVANCED_FRONT_H
#define ADVANCED_FRONT_H
#include "../common/shapes.h"
namespace p2t {
struct Node;
// Advancing front node
struct Node {
Point* point;
Triangle* triangle;
Node* next;
Node* prev;
double value;
Node(Point& p) : point(&p), triangle(NULL), next(NULL), prev(NULL), value(p.x)
{
}
Node(Point& p, Triangle& t) : point(&p), triangle(&t), next(NULL), prev(NULL), value(p.x)
{
}
};
// Advancing front
class AdvancingFront {
public:
AdvancingFront(Node& head, Node& tail);
// Destructor
~AdvancingFront();
Node* head();
void set_head(Node* node);
Node* tail();
void set_tail(Node* node);
Node* search();
void set_search(Node* node);
/// Locate insertion point along advancing front
Node* LocateNode(double x);
Node* LocatePoint(const Point* point);
private:
Node* head_, *tail_, *search_node_;
Node* FindSearchNode(double x);
};
inline Node* AdvancingFront::head()
{
return head_;
}
inline void AdvancingFront::set_head(Node* node)
{
head_ = node;
}
inline Node* AdvancingFront::tail()
{
return tail_;
}
inline void AdvancingFront::set_tail(Node* node)
{
tail_ = node;
}
inline Node* AdvancingFront::search()
{
return search_node_;
}
inline void AdvancingFront::set_search(Node* node)
{
search_node_ = node;
}
}
#endif

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/*
* Poly2Tri Copyright (c) 2009-2010, Poly2Tri Contributors
* http://code.google.com/p/poly2tri/
*
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without modification,
* are permitted provided that the following conditions are met:
*
* * Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
* * Neither the name of Poly2Tri nor the names of its contributors may be
* used to endorse or promote products derived from this software without specific
* prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include "cdt.h"
namespace p2t {
CDT::CDT(const std::vector<Point*>& polyline)
{
sweep_context_ = new SweepContext(polyline);
sweep_ = new Sweep;
}
void CDT::AddHole(const std::vector<Point*>& polyline)
{
sweep_context_->AddHole(polyline);
}
void CDT::AddPoint(Point* point) {
sweep_context_->AddPoint(point);
}
void CDT::Triangulate()
{
sweep_->Triangulate(*sweep_context_);
}
std::vector<p2t::Triangle*> CDT::GetTriangles()
{
return sweep_context_->GetTriangles();
}
std::list<p2t::Triangle*> CDT::GetMap()
{
return sweep_context_->GetMap();
}
CDT::~CDT()
{
delete sweep_context_;
delete sweep_;
}
}

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/*
* Poly2Tri Copyright (c) 2009-2010, Poly2Tri Contributors
* http://code.google.com/p/poly2tri/
*
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without modification,
* are permitted provided that the following conditions are met:
*
* * Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
* * Neither the name of Poly2Tri nor the names of its contributors may be
* used to endorse or promote products derived from this software without specific
* prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef CDT_H
#define CDT_H
#include "advancing_front.h"
#include "sweep_context.h"
#include "sweep.h"
/**
*
* @author Mason Green <mason.green@gmail.com>
*
*/
namespace p2t {
class CDT
{
public:
/**
* Constructor - add polyline with non repeating points
*
* @param polyline
*/
CDT(const std::vector<Point*>& polyline);
/**
* Destructor - clean up memory
*/
~CDT();
/**
* Add a hole
*
* @param polyline
*/
void AddHole(const 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_;
};
}
#endif

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/*
* Poly2Tri Copyright (c) 2009-2010, Poly2Tri Contributors
* http://code.google.com/p/poly2tri/
*
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without modification,
* are permitted provided that the following conditions are met:
*
* * Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
* * Neither the name of Poly2Tri nor the names of its contributors may be
* used to endorse or promote products derived from this software without specific
* prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <stdexcept>
#include "sweep.h"
#include "sweep_context.h"
#include "advancing_front.h"
#include "../common/utils.h"
namespace p2t {
// Triangulate simple polygon with holes
void Sweep::Triangulate(SweepContext& tcx)
{
tcx.InitTriangulation();
tcx.CreateAdvancingFront(nodes_);
// Sweep points; build mesh
SweepPoints(tcx);
// Clean up
FinalizationPolygon(tcx);
}
void Sweep::SweepPoints(SweepContext& tcx)
{
for (size_t i = 1; i < tcx.point_count(); i++) {
Point& point = *tcx.GetPoint(i);
Node* node = &PointEvent(tcx, point);
for (unsigned int i = 0; i < point.edge_list.size(); i++) {
EdgeEvent(tcx, point.edge_list[i], node);
}
}
}
void Sweep::FinalizationPolygon(SweepContext& tcx)
{
// Get an Internal triangle to start with
Triangle* t = tcx.front()->head()->next->triangle;
Point* p = tcx.front()->head()->next->point;
while (!t->GetConstrainedEdgeCW(*p)) {
t = t->NeighborCCW(*p);
}
// Collect interior triangles constrained by edges
tcx.MeshClean(*t);
}
Node& Sweep::PointEvent(SweepContext& tcx, Point& point)
{
Node& node = tcx.LocateNode(point);
Node& new_node = NewFrontTriangle(tcx, point, node);
// Only need to check +epsilon since point never have smaller
// x value than node due to how we fetch nodes from the front
if (point.x <= node.point->x + EPSILON) {
Fill(tcx, node);
}
//tcx.AddNode(new_node);
FillAdvancingFront(tcx, new_node);
return new_node;
}
void Sweep::EdgeEvent(SweepContext& tcx, Edge* edge, Node* node)
{
tcx.edge_event.constrained_edge = edge;
tcx.edge_event.right = (edge->p->x > edge->q->x);
if (IsEdgeSideOfTriangle(*node->triangle, *edge->p, *edge->q)) {
return;
}
// For now we will do all needed filling
// TODO: integrate with flip process might give some better performance
// but for now this avoid the issue with cases that needs both flips and fills
FillEdgeEvent(tcx, edge, node);
EdgeEvent(tcx, *edge->p, *edge->q, node->triangle, *edge->q);
}
void Sweep::EdgeEvent(SweepContext& tcx, Point& ep, Point& eq, Triangle* triangle, Point& point)
{
if (IsEdgeSideOfTriangle(*triangle, ep, eq)) {
return;
}
Point* p1 = triangle->PointCCW(point);
Orientation o1 = Orient2d(eq, *p1, ep);
if (o1 == COLLINEAR) {
// ASSIMP_CHANGE (aramis_acg)
throw std::runtime_error("EdgeEvent - collinear points not supported");
if( triangle->Contains(&eq, p1)) {
triangle->MarkConstrainedEdge(&eq, p1 );
// We are modifying the constraint maybe it would be better to
// not change the given constraint and just keep a variable for the new constraint
tcx.edge_event.constrained_edge->q = p1;
triangle = &triangle->NeighborAcross(point);
EdgeEvent( tcx, ep, *p1, triangle, *p1 );
} else {
// ASSIMP_CHANGE (aramis_acg)
std::runtime_error("EdgeEvent - collinear points not supported");
}
return;
}
Point* p2 = triangle->PointCW(point);
Orientation o2 = Orient2d(eq, *p2, ep);
if (o2 == COLLINEAR) {
// ASSIMP_CHANGE (aramis_acg)
throw std::runtime_error("EdgeEvent - collinear points not supported");
if( triangle->Contains(&eq, p2)) {
triangle->MarkConstrainedEdge(&eq, p2 );
// We are modifying the constraint maybe it would be better to
// not change the given constraint and just keep a variable for the new constraint
tcx.edge_event.constrained_edge->q = p2;
triangle = &triangle->NeighborAcross(point);
EdgeEvent( tcx, ep, *p2, triangle, *p2 );
} else {
// ASSIMP_CHANGE (aramis_acg)
throw std::runtime_error("EdgeEvent - collinear points not supported");
}
return;
}
if (o1 == o2) {
// Need to decide if we are rotating CW or CCW to get to a triangle
// that will cross edge
if (o1 == CW) {
triangle = triangle->NeighborCCW(point);
} else{
triangle = triangle->NeighborCW(point);
}
EdgeEvent(tcx, ep, eq, triangle, point);
} else {
// This triangle crosses constraint so lets flippin start!
FlipEdgeEvent(tcx, ep, eq, triangle, point);
}
}
bool Sweep::IsEdgeSideOfTriangle(Triangle& triangle, Point& ep, Point& eq)
{
const int index = triangle.EdgeIndex(&ep, &eq);
if (index != -1) {
triangle.MarkConstrainedEdge(index);
Triangle* t = triangle.GetNeighbor(index);
if (t) {
t->MarkConstrainedEdge(&ep, &eq);
}
return true;
}
return false;
}
Node& Sweep::NewFrontTriangle(SweepContext& tcx, Point& point, Node& node)
{
Triangle* triangle = new Triangle(point, *node.point, *node.next->point);
triangle->MarkNeighbor(*node.triangle);
tcx.AddToMap(triangle);
Node* new_node = new Node(point);
nodes_.push_back(new_node);
new_node->next = node.next;
new_node->prev = &node;
node.next->prev = new_node;
node.next = new_node;
if (!Legalize(tcx, *triangle)) {
tcx.MapTriangleToNodes(*triangle);
}
return *new_node;
}
void Sweep::Fill(SweepContext& tcx, Node& node)
{
Triangle* triangle = new Triangle(*node.prev->point, *node.point, *node.next->point);
// TODO: should copy the constrained_edge value from neighbor triangles
// for now constrained_edge values are copied during the legalize
triangle->MarkNeighbor(*node.prev->triangle);
triangle->MarkNeighbor(*node.triangle);
tcx.AddToMap(triangle);
// Update the advancing front
node.prev->next = node.next;
node.next->prev = node.prev;
// If it was legalized the triangle has already been mapped
if (!Legalize(tcx, *triangle)) {
tcx.MapTriangleToNodes(*triangle);
}
}
void Sweep::FillAdvancingFront(SweepContext& tcx, Node& n)
{
// Fill right holes
Node* node = n.next;
while (node->next) {
// if HoleAngle exceeds 90 degrees then break.
if (LargeHole_DontFill(node)) break;
Fill(tcx, *node);
node = node->next;
}
// Fill left holes
node = n.prev;
while (node->prev) {
// if HoleAngle exceeds 90 degrees then break.
if (LargeHole_DontFill(node)) break;
Fill(tcx, *node);
node = node->prev;
}
// Fill right basins
if (n.next && n.next->next) {
const double angle = BasinAngle(n);
if (angle < PI_3div4) {
FillBasin(tcx, n);
}
}
}
// True if HoleAngle exceeds 90 degrees.
bool Sweep::LargeHole_DontFill(const Node* node) const {
const Node* nextNode = node->next;
const Node* prevNode = node->prev;
if (!AngleExceeds90Degrees(node->point, nextNode->point, prevNode->point))
return false;
// Check additional points on front.
const Node* next2Node = nextNode->next;
// "..Plus.." because only want angles on same side as point being added.
if ((next2Node != NULL) && !AngleExceedsPlus90DegreesOrIsNegative(node->point, next2Node->point, prevNode->point))
return false;
const Node* prev2Node = prevNode->prev;
// "..Plus.." because only want angles on same side as point being added.
if ((prev2Node != NULL) && !AngleExceedsPlus90DegreesOrIsNegative(node->point, nextNode->point, prev2Node->point))
return false;
return true;
}
bool Sweep::AngleExceeds90Degrees(const Point* origin, const Point* pa, const Point* pb) const {
const double angle = Angle(origin, pa, pb);
return ((angle > PI_div2) || (angle < -PI_div2));
}
bool Sweep::AngleExceedsPlus90DegreesOrIsNegative(const Point* origin, const Point* pa, const Point* pb) const {
const double angle = Angle(origin, pa, pb);
return (angle > PI_div2) || (angle < 0);
}
double Sweep::Angle(const Point* origin, const Point* pa, const Point* pb) const {
/* Complex plane
* ab = cosA +i*sinA
* ab = (ax + ay*i)(bx + by*i) = (ax*bx + ay*by) + i(ax*by-ay*bx)
* atan2(y,x) computes the principal value of the argument function
* applied to the complex number x+iy
* Where x = ax*bx + ay*by
* y = ax*by - ay*bx
*/
const double px = origin->x;
const double py = origin->y;
const double ax = pa->x- px;
const double ay = pa->y - py;
const double bx = pb->x - px;
const double by = pb->y - py;
const double x = ax * by - ay * bx;
const double y = ax * bx + ay * by;
return atan2(x, y);
}
double Sweep::BasinAngle(const Node& node) const
{
const double ax = node.point->x - node.next->next->point->x;
const double ay = node.point->y - node.next->next->point->y;
return atan2(ay, ax);
}
double Sweep::HoleAngle(const Node& node) const
{
/* Complex plane
* ab = cosA +i*sinA
* ab = (ax + ay*i)(bx + by*i) = (ax*bx + ay*by) + i(ax*by-ay*bx)
* atan2(y,x) computes the principal value of the argument function
* applied to the complex number x+iy
* Where x = ax*bx + ay*by
* y = ax*by - ay*bx
*/
const double ax = node.next->point->x - node.point->x;
const double ay = node.next->point->y - node.point->y;
const double bx = node.prev->point->x - node.point->x;
const double by = node.prev->point->y - node.point->y;
return atan2(ax * by - ay * bx, ax * bx + ay * by);
}
bool Sweep::Legalize(SweepContext& tcx, Triangle& t)
{
// To legalize a triangle we start by finding if any of the three edges
// violate the Delaunay condition
for (int i = 0; i < 3; i++) {
if (t.delaunay_edge[i])
continue;
Triangle* ot = t.GetNeighbor(i);
if (ot) {
Point* p = t.GetPoint(i);
Point* op = ot->OppositePoint(t, *p);
int oi = ot->Index(op);
// If this is a Constrained Edge or a Delaunay Edge(only during recursive legalization)
// then we should not try to legalize
if (ot->constrained_edge[oi] || ot->delaunay_edge[oi]) {
t.constrained_edge[i] = ot->constrained_edge[oi];
continue;
}
bool inside = Incircle(*p, *t.PointCCW(*p), *t.PointCW(*p), *op);
if (inside) {
// Lets mark this shared edge as Delaunay
t.delaunay_edge[i] = true;
ot->delaunay_edge[oi] = true;
// Lets rotate shared edge one vertex CW to legalize it
RotateTrianglePair(t, *p, *ot, *op);
// We now got one valid Delaunay Edge shared by two triangles
// This gives us 4 new edges to check for Delaunay
// Make sure that triangle to node mapping is done only one time for a specific triangle
bool not_legalized = !Legalize(tcx, t);
if (not_legalized) {
tcx.MapTriangleToNodes(t);
}
not_legalized = !Legalize(tcx, *ot);
if (not_legalized)
tcx.MapTriangleToNodes(*ot);
// Reset the Delaunay edges, since they only are valid Delaunay edges
// until we add a new triangle or point.
// XXX: need to think about this. Can these edges be tried after we
// return to previous recursive level?
t.delaunay_edge[i] = false;
ot->delaunay_edge[oi] = false;
// If triangle have been legalized no need to check the other edges since
// the recursive legalization will handles those so we can end here.
return true;
}
}
}
return false;
}
bool Sweep::Incircle(const Point& pa, const Point& pb, const Point& pc, const Point& pd) const
{
const double adx = pa.x - pd.x;
const double ady = pa.y - pd.y;
const double bdx = pb.x - pd.x;
const double bdy = pb.y - pd.y;
const double adxbdy = adx * bdy;
const double bdxady = bdx * ady;
const double oabd = adxbdy - bdxady;
if (oabd <= 0)
return false;
const double cdx = pc.x - pd.x;
const double cdy = pc.y - pd.y;
const double cdxady = cdx * ady;
const double adxcdy = adx * cdy;
const double ocad = cdxady - adxcdy;
if (ocad <= 0)
return false;
const double bdxcdy = bdx * cdy;
const double cdxbdy = cdx * bdy;
const double alift = adx * adx + ady * ady;
const double blift = bdx * bdx + bdy * bdy;
const double clift = cdx * cdx + cdy * cdy;
const double det = alift * (bdxcdy - cdxbdy) + blift * ocad + clift * oabd;
return det > 0;
}
void Sweep::RotateTrianglePair(Triangle& t, Point& p, Triangle& ot, Point& op) const
{
Triangle* n1, *n2, *n3, *n4;
n1 = t.NeighborCCW(p);
n2 = t.NeighborCW(p);
n3 = ot.NeighborCCW(op);
n4 = ot.NeighborCW(op);
bool ce1, ce2, ce3, ce4;
ce1 = t.GetConstrainedEdgeCCW(p);
ce2 = t.GetConstrainedEdgeCW(p);
ce3 = ot.GetConstrainedEdgeCCW(op);
ce4 = ot.GetConstrainedEdgeCW(op);
bool de1, de2, de3, de4;
de1 = t.GetDelunayEdgeCCW(p);
de2 = t.GetDelunayEdgeCW(p);
de3 = ot.GetDelunayEdgeCCW(op);
de4 = ot.GetDelunayEdgeCW(op);
t.Legalize(p, op);
ot.Legalize(op, p);
// Remap delaunay_edge
ot.SetDelunayEdgeCCW(p, de1);
t.SetDelunayEdgeCW(p, de2);
t.SetDelunayEdgeCCW(op, de3);
ot.SetDelunayEdgeCW(op, de4);
// Remap constrained_edge
ot.SetConstrainedEdgeCCW(p, ce1);
t.SetConstrainedEdgeCW(p, ce2);
t.SetConstrainedEdgeCCW(op, ce3);
ot.SetConstrainedEdgeCW(op, ce4);
// Remap neighbors
// XXX: might optimize the markNeighbor by keeping track of
// what side should be assigned to what neighbor after the
// rotation. Now mark neighbor does lots of testing to find
// the right side.
t.ClearNeighbors();
ot.ClearNeighbors();
if (n1) ot.MarkNeighbor(*n1);
if (n2) t.MarkNeighbor(*n2);
if (n3) t.MarkNeighbor(*n3);
if (n4) ot.MarkNeighbor(*n4);
t.MarkNeighbor(ot);
}
void Sweep::FillBasin(SweepContext& tcx, Node& node)
{
if (Orient2d(*node.point, *node.next->point, *node.next->next->point) == CCW) {
tcx.basin.left_node = node.next->next;
} else {
tcx.basin.left_node = node.next;
}
// Find the bottom and right node
tcx.basin.bottom_node = tcx.basin.left_node;
while (tcx.basin.bottom_node->next
&& tcx.basin.bottom_node->point->y >= tcx.basin.bottom_node->next->point->y) {
tcx.basin.bottom_node = tcx.basin.bottom_node->next;
}
if (tcx.basin.bottom_node == tcx.basin.left_node) {
// No valid basin
return;
}
tcx.basin.right_node = tcx.basin.bottom_node;
while (tcx.basin.right_node->next
&& tcx.basin.right_node->point->y < tcx.basin.right_node->next->point->y) {
tcx.basin.right_node = tcx.basin.right_node->next;
}
if (tcx.basin.right_node == tcx.basin.bottom_node) {
// No valid basins
return;
}
tcx.basin.width = tcx.basin.right_node->point->x - tcx.basin.left_node->point->x;
tcx.basin.left_highest = tcx.basin.left_node->point->y > tcx.basin.right_node->point->y;
FillBasinReq(tcx, tcx.basin.bottom_node);
}
void Sweep::FillBasinReq(SweepContext& tcx, Node* node)
{
// if shallow stop filling
if (IsShallow(tcx, *node)) {
return;
}
Fill(tcx, *node);
if (node->prev == tcx.basin.left_node && node->next == tcx.basin.right_node) {
return;
} else if (node->prev == tcx.basin.left_node) {
Orientation o = Orient2d(*node->point, *node->next->point, *node->next->next->point);
if (o == CW) {
return;
}
node = node->next;
} else if (node->next == tcx.basin.right_node) {
Orientation o = Orient2d(*node->point, *node->prev->point, *node->prev->prev->point);
if (o == CCW) {
return;
}
node = node->prev;
} else {
// Continue with the neighbor node with lowest Y value
if (node->prev->point->y < node->next->point->y) {
node = node->prev;
} else {
node = node->next;
}
}
FillBasinReq(tcx, node);
}
bool Sweep::IsShallow(SweepContext& tcx, Node& node)
{
double height;
if (tcx.basin.left_highest) {
height = tcx.basin.left_node->point->y - node.point->y;
} else {
height = tcx.basin.right_node->point->y - node.point->y;
}
// if shallow stop filling
if (tcx.basin.width > height) {
return true;
}
return false;
}
void Sweep::FillEdgeEvent(SweepContext& tcx, Edge* edge, Node* node)
{
if (tcx.edge_event.right) {
FillRightAboveEdgeEvent(tcx, edge, node);
} else {
FillLeftAboveEdgeEvent(tcx, edge, node);
}
}
void Sweep::FillRightAboveEdgeEvent(SweepContext& tcx, Edge* edge, Node* node)
{
while (node->next->point->x < edge->p->x) {
// Check if next node is below the edge
if (Orient2d(*edge->q, *node->next->point, *edge->p) == CCW) {
FillRightBelowEdgeEvent(tcx, edge, *node);
} else {
node = node->next;
}
}
}
void Sweep::FillRightBelowEdgeEvent(SweepContext& tcx, Edge* edge, Node& node)
{
if (node.point->x < edge->p->x) {
if (Orient2d(*node.point, *node.next->point, *node.next->next->point) == CCW) {
// Concave
FillRightConcaveEdgeEvent(tcx, edge, node);
} else{
// Convex
FillRightConvexEdgeEvent(tcx, edge, node);
// Retry this one
FillRightBelowEdgeEvent(tcx, edge, node);
}
}
}
void Sweep::FillRightConcaveEdgeEvent(SweepContext& tcx, Edge* edge, Node& node)
{
Fill(tcx, *node.next);
if (node.next->point != edge->p) {
// Next above or below edge?
if (Orient2d(*edge->q, *node.next->point, *edge->p) == CCW) {
// Below
if (Orient2d(*node.point, *node.next->point, *node.next->next->point) == CCW) {
// Next is concave
FillRightConcaveEdgeEvent(tcx, edge, node);
} else {
// Next is convex
}
}
}
}
void Sweep::FillRightConvexEdgeEvent(SweepContext& tcx, Edge* edge, Node& node)
{
// Next concave or convex?
if (Orient2d(*node.next->point, *node.next->next->point, *node.next->next->next->point) == CCW) {
// Concave
FillRightConcaveEdgeEvent(tcx, edge, *node.next);
} else{
// Convex
// Next above or below edge?
if (Orient2d(*edge->q, *node.next->next->point, *edge->p) == CCW) {
// Below
FillRightConvexEdgeEvent(tcx, edge, *node.next);
} else{
// Above
}
}
}
void Sweep::FillLeftAboveEdgeEvent(SweepContext& tcx, Edge* edge, Node* node)
{
while (node->prev->point->x > edge->p->x) {
// Check if next node is below the edge
if (Orient2d(*edge->q, *node->prev->point, *edge->p) == CW) {
FillLeftBelowEdgeEvent(tcx, edge, *node);
} else {
node = node->prev;
}
}
}
void Sweep::FillLeftBelowEdgeEvent(SweepContext& tcx, Edge* edge, Node& node)
{
if (node.point->x > edge->p->x) {
if (Orient2d(*node.point, *node.prev->point, *node.prev->prev->point) == CW) {
// Concave
FillLeftConcaveEdgeEvent(tcx, edge, node);
} else {
// Convex
FillLeftConvexEdgeEvent(tcx, edge, node);
// Retry this one
FillLeftBelowEdgeEvent(tcx, edge, node);
}
}
}
void Sweep::FillLeftConvexEdgeEvent(SweepContext& tcx, Edge* edge, Node& node)
{
// Next concave or convex?
if (Orient2d(*node.prev->point, *node.prev->prev->point, *node.prev->prev->prev->point) == CW) {
// Concave
FillLeftConcaveEdgeEvent(tcx, edge, *node.prev);
} else{
// Convex
// Next above or below edge?
if (Orient2d(*edge->q, *node.prev->prev->point, *edge->p) == CW) {
// Below
FillLeftConvexEdgeEvent(tcx, edge, *node.prev);
} else{
// Above
}
}
}
void Sweep::FillLeftConcaveEdgeEvent(SweepContext& tcx, Edge* edge, Node& node)
{
Fill(tcx, *node.prev);
if (node.prev->point != edge->p) {
// Next above or below edge?
if (Orient2d(*edge->q, *node.prev->point, *edge->p) == CW) {
// Below
if (Orient2d(*node.point, *node.prev->point, *node.prev->prev->point) == CW) {
// Next is concave
FillLeftConcaveEdgeEvent(tcx, edge, node);
} else{
// Next is convex
}
}
}
}
void Sweep::FlipEdgeEvent(SweepContext& tcx, Point& ep, Point& eq, Triangle* t, Point& p)
{
Triangle& ot = t->NeighborAcross(p);
Point& op = *ot.OppositePoint(*t, p);
if (InScanArea(p, *t->PointCCW(p), *t->PointCW(p), op)) {
// Lets rotate shared edge one vertex CW
RotateTrianglePair(*t, p, ot, op);
tcx.MapTriangleToNodes(*t);
tcx.MapTriangleToNodes(ot);
if (p == eq && op == ep) {
if (eq == *tcx.edge_event.constrained_edge->q && ep == *tcx.edge_event.constrained_edge->p) {
t->MarkConstrainedEdge(&ep, &eq);
ot.MarkConstrainedEdge(&ep, &eq);
Legalize(tcx, *t);
Legalize(tcx, ot);
} else {
// XXX: I think one of the triangles should be legalized here?
}
} else {
Orientation o = Orient2d(eq, op, ep);
t = &NextFlipTriangle(tcx, (int)o, *t, ot, p, op);
FlipEdgeEvent(tcx, ep, eq, t, p);
}
} else {
Point& newP = NextFlipPoint(ep, eq, ot, op);
FlipScanEdgeEvent(tcx, ep, eq, *t, ot, newP);
EdgeEvent(tcx, ep, eq, t, p);
}
}
Triangle& Sweep::NextFlipTriangle(SweepContext& tcx, int o, Triangle& t, Triangle& ot, Point& p, Point& op)
{
if (o == CCW) {
// ot is not crossing edge after flip
int edge_index = ot.EdgeIndex(&p, &op);
ot.delaunay_edge[edge_index] = true;
Legalize(tcx, ot);
ot.ClearDelunayEdges();
return t;
}
// t is not crossing edge after flip
int edge_index = t.EdgeIndex(&p, &op);
t.delaunay_edge[edge_index] = true;
Legalize(tcx, t);
t.ClearDelunayEdges();
return ot;
}
Point& Sweep::NextFlipPoint(Point& ep, Point& eq, Triangle& ot, Point& op)
{
Orientation o2d = Orient2d(eq, op, ep);
if (o2d == CW) {
// Right
return *ot.PointCCW(op);
} else if (o2d == CCW) {
// Left
return *ot.PointCW(op);
}
throw std::runtime_error("[Unsupported] Opposing point on constrained edge");
}
void Sweep::FlipScanEdgeEvent(SweepContext& tcx, Point& ep, Point& eq, Triangle& flip_triangle,
Triangle& t, Point& p)
{
Triangle& ot = t.NeighborAcross(p);
Point& op = *ot.OppositePoint(t, p);
if (InScanArea(eq, *flip_triangle.PointCCW(eq), *flip_triangle.PointCW(eq), op)) {
// flip with new edge op->eq
FlipEdgeEvent(tcx, eq, op, &ot, op);
// TODO: Actually I just figured out that it should be possible to
// improve this by getting the next ot and op before the the above
// flip and continue the flipScanEdgeEvent here
// set new ot and op here and loop back to inScanArea test
// also need to set a new flip_triangle first
// Turns out at first glance that this is somewhat complicated
// so it will have to wait.
} else{
Point& newP = NextFlipPoint(ep, eq, ot, op);
FlipScanEdgeEvent(tcx, ep, eq, flip_triangle, ot, newP);
}
}
Sweep::~Sweep() {
// Clean up memory
for(size_t i = 0; i < nodes_.size(); i++) {
delete nodes_[i];
}
}
}

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/*
* Poly2Tri Copyright (c) 2009-2010, Poly2Tri Contributors
* http://code.google.com/p/poly2tri/
*
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without modification,
* are permitted provided that the following conditions are met:
*
* * Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
* * Neither the name of Poly2Tri nor the names of its contributors may be
* used to endorse or promote products derived from this software without specific
* prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
/**
* Sweep-line, Constrained Delauney Triangulation (CDT) See: Domiter, V. and
* Zalik, B.(2008)'Sweep-line algorithm for constrained Delaunay triangulation',
* International Journal of Geographical Information Science
*
* "FlipScan" Constrained Edge Algorithm invented by Thomas ?hl?n, thahlen@gmail.com
*/
#ifndef SWEEP_H
#define SWEEP_H
#include <vector>
namespace p2t {
class SweepContext;
struct Node;
struct Point;
struct Edge;
class Triangle;
class Sweep
{
public:
/**
* Triangulate
*
* @param tcx
*/
void Triangulate(SweepContext& tcx);
/**
* Destructor - clean up memory
*/
~Sweep();
private:
/**
* Start sweeping the Y-sorted point set from bottom to top
*
* @param tcx
*/
void SweepPoints(SweepContext& tcx);
/**
* 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);
/**
*
*
* @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);
/**
* Creates a new front triangle and legalize it
*
* @param tcx
* @param point
* @param node
* @return
*/
Node& NewFrontTriangle(SweepContext& tcx, Point& point, 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);
/**
* Returns true if triangle was legalized
*/
bool Legalize(SweepContext& tcx, Triangle& t);
/**
* <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(const Point& pa, const Point& pb, const Point& pc, const Point& pd) const;
/**
* 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) const;
/**
* Fills holes in the Advancing Front
*
*
* @param tcx
* @param n
*/
void FillAdvancingFront(SweepContext& tcx, Node& n);
// Decision-making about when to Fill hole.
// Contributed by ToolmakerSteve2
bool LargeHole_DontFill(const Node* node) const;
bool AngleExceeds90Degrees(const Point* origin, const Point* pa, const Point* pb) const;
bool AngleExceedsPlus90DegreesOrIsNegative(const Point* origin, const Point* pa, const Point* pb) const;
double Angle(const Point* origin, const Point* pa, const Point* pb) const;
/**
*
* @param node - middle node
* @return the angle between 3 front nodes
*/
double HoleAngle(const Node& node) const;
/**
* The basin angle is decided against the horizontal line [1,0]
*/
double BasinAngle(const Node& node) const;
/**
* 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);
/**
* 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 IsEdgeSideOfTriangle(Triangle& triangle, Point& ep, Point& eq);
void FillEdgeEvent(SweepContext& tcx, Edge* edge, Node* node);
void FillRightAboveEdgeEvent(SweepContext& tcx, Edge* edge, Node* node);
void FillRightBelowEdgeEvent(SweepContext& tcx, Edge* edge, Node& node);
void FillRightConcaveEdgeEvent(SweepContext& tcx, Edge* edge, Node& node);
void FillRightConvexEdgeEvent(SweepContext& tcx, Edge* edge, Node& node);
void FillLeftAboveEdgeEvent(SweepContext& tcx, Edge* edge, Node* node);
void FillLeftBelowEdgeEvent(SweepContext& tcx, Edge* edge, Node& node);
void FillLeftConcaveEdgeEvent(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);
/**
* 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);
/**
* 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);
/**
* 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);
std::vector<Node*> nodes_;
};
}
#endif

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/*
* Poly2Tri Copyright (c) 2009-2010, Poly2Tri Contributors
* http://code.google.com/p/poly2tri/
*
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without modification,
* are permitted provided that the following conditions are met:
*
* * Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
* * Neither the name of Poly2Tri nor the names of its contributors may be
* used to endorse or promote products derived from this software without specific
* prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include "sweep_context.h"
#include <algorithm>
#include "advancing_front.h"
namespace p2t {
SweepContext::SweepContext(const std::vector<Point*>& polyline) : points_(polyline),
front_(0),
head_(0),
tail_(0),
af_head_(0),
af_middle_(0),
af_tail_(0)
{
InitEdges(points_);
}
void SweepContext::AddHole(const std::vector<Point*>& polyline)
{
InitEdges(polyline);
for(unsigned int i = 0; i < polyline.size(); i++) {
points_.push_back(polyline[i]);
}
}
void SweepContext::AddPoint(Point* point) {
points_.push_back(point);
}
std::vector<Triangle*> &SweepContext::GetTriangles()
{
return triangles_;
}
std::list<Triangle*> &SweepContext::GetMap()
{
return map_;
}
void SweepContext::InitTriangulation()
{
double xmax(points_[0]->x), xmin(points_[0]->x);
double ymax(points_[0]->y), ymin(points_[0]->y);
// Calculate bounds.
for (unsigned int i = 0; i < points_.size(); i++) {
Point& p = *points_[i];
if (p.x > xmax)
xmax = p.x;
if (p.x < xmin)
xmin = p.x;
if (p.y > ymax)
ymax = p.y;
if (p.y < ymin)
ymin = p.y;
}
double dx = kAlpha * (xmax - xmin);
double dy = kAlpha * (ymax - ymin);
head_ = new Point(xmax + dx, ymin - dy);
tail_ = new Point(xmin - dx, ymin - dy);
// Sort points along y-axis
std::sort(points_.begin(), points_.end(), cmp);
}
void SweepContext::InitEdges(const std::vector<Point*>& polyline)
{
size_t num_points = polyline.size();
for (size_t i = 0; i < num_points; i++) {
size_t j = i < num_points - 1 ? i + 1 : 0;
edge_list.push_back(new Edge(*polyline[i], *polyline[j]));
}
}
Point* SweepContext::GetPoint(size_t index)
{
return points_[index];
}
void SweepContext::AddToMap(Triangle* triangle)
{
map_.push_back(triangle);
}
Node& SweepContext::LocateNode(const Point& point)
{
// TODO implement search tree
return *front_->LocateNode(point.x);
}
void SweepContext::CreateAdvancingFront(const std::vector<Node*>& nodes)
{
(void) nodes;
// Initial triangle
Triangle* triangle = new Triangle(*points_[0], *tail_, *head_);
map_.push_back(triangle);
af_head_ = new Node(*triangle->GetPoint(1), *triangle);
af_middle_ = new Node(*triangle->GetPoint(0), *triangle);
af_tail_ = new Node(*triangle->GetPoint(2));
front_ = new AdvancingFront(*af_head_, *af_tail_);
// TODO: More intuitive if head is middles next and not previous?
// so swap head and tail
af_head_->next = af_middle_;
af_middle_->next = af_tail_;
af_middle_->prev = af_head_;
af_tail_->prev = af_middle_;
}
void SweepContext::RemoveNode(Node* node)
{
delete node;
}
void SweepContext::MapTriangleToNodes(Triangle& t)
{
for (int i = 0; i < 3; i++) {
if (!t.GetNeighbor(i)) {
Node* n = front_->LocatePoint(t.PointCW(*t.GetPoint(i)));
if (n)
n->triangle = &t;
}
}
}
void SweepContext::RemoveFromMap(Triangle* triangle)
{
map_.remove(triangle);
}
void SweepContext::MeshClean(Triangle& triangle)
{
std::vector<Triangle *> triangles;
triangles.push_back(&triangle);
while(!triangles.empty()){
Triangle *t = triangles.back();
triangles.pop_back();
if (t != NULL && !t->IsInterior()) {
t->IsInterior(true);
triangles_.push_back(t);
for (int i = 0; i < 3; i++) {
if (!t->constrained_edge[i])
triangles.push_back(t->GetNeighbor(i));
}
}
}
}
SweepContext::~SweepContext()
{
// Clean up memory
delete head_;
delete tail_;
delete front_;
delete af_head_;
delete af_middle_;
delete af_tail_;
typedef std::list<Triangle*> type_list;
for(type_list::iterator iter = map_.begin(); iter != map_.end(); ++iter) {
Triangle* ptr = *iter;
delete ptr;
}
for(unsigned int i = 0; i < edge_list.size(); i++) {
delete edge_list[i];
}
}
}

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@@ -0,0 +1,186 @@
/*
* Poly2Tri Copyright (c) 2009-2010, Poly2Tri Contributors
* http://code.google.com/p/poly2tri/
*
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without modification,
* are permitted provided that the following conditions are met:
*
* * Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
* * Neither the name of Poly2Tri nor the names of its contributors may be
* used to endorse or promote products derived from this software without specific
* prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef SWEEP_CONTEXT_H
#define SWEEP_CONTEXT_H
#include <list>
#include <vector>
#include <cstddef>
namespace p2t {
// Inital triangle factor, seed triangle will extend 30% of
// PointSet width to both left and right.
const double kAlpha = 0.3;
struct Point;
class Triangle;
struct Node;
struct Edge;
class AdvancingFront;
class SweepContext {
public:
/// Constructor
SweepContext(const std::vector<Point*>& polyline);
/// Destructor
~SweepContext();
void set_head(Point* p1);
Point* head() const;
void set_tail(Point* p1);
Point* tail() const;
size_t point_count() const;
Node& LocateNode(const Point& point);
void RemoveNode(Node* node);
void CreateAdvancingFront(const std::vector<Node*>& nodes);
/// Try to map a node to all sides of this triangle that don't have a neighbor
void MapTriangleToNodes(Triangle& t);
void AddToMap(Triangle* triangle);
Point* GetPoint(size_t index);
Point* GetPoints();
void RemoveFromMap(Triangle* triangle);
void AddHole(const std::vector<Point*>& polyline);
void AddPoint(Point* point);
AdvancingFront* front() const;
void MeshClean(Triangle& triangle);
std::vector<Triangle*> &GetTriangles();
std::list<Triangle*> &GetMap();
std::vector<Edge*> edge_list;
struct Basin {
Node* left_node;
Node* bottom_node;
Node* right_node;
double width;
bool left_highest;
Basin() : left_node(NULL), bottom_node(NULL), right_node(NULL), width(0.0), left_highest(false)
{
}
void Clear()
{
left_node = NULL;
bottom_node = NULL;
right_node = NULL;
width = 0.0;
left_highest = false;
}
};
struct EdgeEvent {
Edge* constrained_edge;
bool right;
EdgeEvent() : constrained_edge(NULL), right(false)
{
}
};
Basin basin;
EdgeEvent edge_event;
private:
friend class Sweep;
std::vector<Triangle*> triangles_;
std::list<Triangle*> map_;
std::vector<Point*> points_;
// Advancing front
AdvancingFront* front_;
// head point used with advancing front
Point* head_;
// tail point used with advancing front
Point* tail_;
Node *af_head_, *af_middle_, *af_tail_;
void InitTriangulation();
void InitEdges(const std::vector<Point*>& polyline);
};
inline AdvancingFront* SweepContext::front() const
{
return front_;
}
inline size_t SweepContext::point_count() const
{
return points_.size();
}
inline void SweepContext::set_head(Point* p1)
{
head_ = p1;
}
inline Point* SweepContext::head() const
{
return head_;
}
inline void SweepContext::set_tail(Point* p1)
{
tail_ = p1;
}
inline Point* SweepContext::tail() const
{
return tail_;
}
}
#endif