72 lines
2.7 KiB
C++
72 lines
2.7 KiB
C++
// ** THIS IS A CODE SNIPPET WHICH WILL EFFICIEINTLY TRIANGULATE ANY
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// ** POLYGON/CONTOUR (without holes) AS A STATIC CLASS. THIS SNIPPET
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// ** IS COMPRISED OF 3 FILES, TRIANGULATE.H, THE HEADER FILE FOR THE
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// ** TRIANGULATE BASE CLASS, TRIANGULATE.CPP, THE IMPLEMENTATION OF
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// ** THE TRIANGULATE BASE CLASS, AND TEST.CPP, A SMALL TEST PROGRAM
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// ** DEMONSTRATING THE USAGE OF THE TRIANGULATOR. THE TRIANGULATE
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// ** BASE CLASS ALSO PROVIDES TWO USEFUL HELPER METHODS, ONE WHICH
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// ** COMPUTES THE AREA OF A POLYGON, AND ANOTHER WHICH DOES AN EFFICENT
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// ** POINT IN A TRIANGLE TEST.
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// ** SUBMITTED BY JOHN W. RATCLIFF (jratcliff@verant.com) July 22, 2000
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/**********************************************************************/
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/************ HEADER FILE FOR TRIANGULATE.H ***************************/
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/**********************************************************************/
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#ifndef TRIANGULATE_H
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#define TRIANGULATE_H
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/*****************************************************************/
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/** Static class to triangulate any contour/polygon efficiently **/
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/** You should replace Vector2d with whatever your own Vector **/
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/** class might be. Does not support polygons with holes. **/
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/** Uses STL vectors to represent a dynamic array of vertices. **/
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/** This code snippet was submitted to FlipCode.com by **/
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/** John W. Ratcliff (jratcliff@verant.com) on July 22, 2000 **/
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/** I did not write the original code/algorithm for this **/
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/** this triangulator, in fact, I can't even remember where I **/
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/** found it in the first place. However, I did rework it into **/
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/** the following black-box static class so you can make easy **/
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/** use of it in your own code. Simply replace Vector2d with **/
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/** whatever your own Vector implementation might be. **/
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/*****************************************************************/
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#include <vector> // Include STL vector class.
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// Typedef an STL vector of vertices which are used to represent
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// a polygon/contour and a series of triangles.
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typedef std::vector< Vec3 > Vector2dVector;
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class CTriangulate
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{
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public:
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// triangulate a contour/polygon, places results in STL vector
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// as series of triangles.
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static bool Process(const Vector2dVector &contour,
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Vector2dVector &result);
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// compute area of a contour/polygon
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static float Area(const Vector2dVector &contour);
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// decide if point Px/Py is inside triangle defined by
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// (Ax,Ay) (Bx,By) (Cx,Cy)
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static bool InsideTriangle(float Ax, float Ay,
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float Bx, float By,
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float Cx, float Cy,
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float Px, float Py);
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private:
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static bool Snip(const Vector2dVector &contour,int u,int v,int w,int n,int *V);
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};
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#endif
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