virtualx-engine/drivers/convex_decomp/b2Polygon.h

/*
 * Copyright (c) 2007 Eric Jordan
 *
 * This software is provided 'as-is', without any express or implied
 * warranty.  In no event will the authors be held liable for any damages
 * arising from the use of this software.
 * Permission is granted to anyone to use this software for any purpose,
 * including commercial applications, and to alter it and redistribute it
 * freely, subject to the following restrictions:
 * 1. The origin of this software must not be misrepresented; you must not
 * claim that you wrote the original software. If you use this software
 * in a product, an acknowledgment in the product documentation would be
 * appreciated but is not required.
 * 2. Altered source versions must be plainly marked as such, and must not be
 * misrepresented as being the original software.
 * 3. This notice may not be removed or altered from any source distribution.
 */

#ifndef B2_POLYGON_H
#define B2_POLYGON_H

#include "b2Triangle.h"
#include "stdio.h"
#include <string.h>
#include <limits.h>
namespace b2ConvexDecomp {

static bool B2_POLYGON_REPORT_ERRORS = false;

class b2Polygon;

int32 remainder(int32 x, int32 modulus);
int32 TriangulatePolygon(float32* xv, float32* yv, int32 vNum, b2Triangle* results);
bool IsEar(int32 i, float32* xv, float32* yv, int32 xvLength); //Not for external use
int32 PolygonizeTriangles(b2Triangle* triangulated, int32 triangulatedLength, b2Polygon* polys, int32 polysLength);
int32 DecomposeConvex(b2Polygon* p, b2Polygon* results, int32 maxPolys);
//void DecomposeConvexAndAddTo(b2Polygon* p, b2Body* bd, b2FixtureDef* prototype);

void ReversePolygon(float32* x, float32* y, int n);

b2Polygon TraceEdge(b2Polygon* p); //For use with self-intersecting polygons, finds outline

class b2Polygon {
	
public:
    const static int32 maxVerticesPerPolygon = b2_maxPolygonVertices;

    float32* x; //vertex arrays
    float32* y;
    int32 nVertices;
	
	float32 area;
	bool areaIsSet;
	
    b2Polygon(float32* _x, float32* _y, int32 nVert);
    b2Polygon(b2Vec2* v, int32 nVert);
	b2Polygon();
    ~b2Polygon();
	
	float32 GetArea();
	
	void MergeParallelEdges(float32 tolerance);
    b2Vec2* GetVertexVecs();
    b2Polygon(b2Triangle& t);
    void Set(const b2Polygon& p);
    bool IsConvex();
	bool IsCCW();
	bool IsUsable(bool printError);
	bool IsUsable();
    bool IsSimple();
   // void AddTo(b2FixtureDef& pd);
	
    b2Polygon* Add(b2Triangle& t);

	void print(){
		printFormatted();
//		for (int32 i=0; i<nVertices; ++i){
//			printf("i: %d, x:%f, y:%f\n",i,x[i],y[i]);
//		}
	}

	void printFormatted(){
		printf("float xv[] = {");
		for (int32 i=0; i<nVertices; ++i){
			printf("%ff,",x[i]);
		}
		printf("};\nfloat yv[] = {");
		for (int32 i=0; i<nVertices; ++i){
			printf("%ff,",y[i]);
		}
		printf("};\n");
	}
    
	b2Polygon(const b2Polygon& p){
		nVertices = p.nVertices;
		area = p.area;
		areaIsSet = p.areaIsSet;
		x = new float32[nVertices];
		y = new float32[nVertices];
		memcpy(x, p.x, nVertices * sizeof(float32));
		memcpy(y, p.y, nVertices * sizeof(float32));
	}

	
};

const int32 MAX_CONNECTED = 32;
const float32 COLLAPSE_DIST_SQR = CMP_EPSILON*CMP_EPSILON;//0.1f;//1000*CMP_EPSILON*1000*CMP_EPSILON;
	
class b2PolyNode{
public:
	b2Vec2 position;
	b2PolyNode* connected[MAX_CONNECTED];
	int32 nConnected;
	bool visited;

	b2PolyNode(b2Vec2& pos);
	b2PolyNode();
	void AddConnection(b2PolyNode& toMe);
	void RemoveConnection(b2PolyNode& fromMe);
	void RemoveConnectionByIndex(int32 index);
	bool IsConnectedTo(b2PolyNode& me);
	b2PolyNode* GetRightestConnection(b2PolyNode* incoming);
	b2PolyNode* GetRightestConnection(b2Vec2& incomingDir);
};


b2Polygon ConvexHull(b2Vec2* v, int nVert);
b2Polygon ConvexHull(float32* cloudX, float32* cloudY, int32 nVert);
}
#endif