// point_in_poly.h count number of edge crossing horizontal line from test
// even, c==1, is inside  pnpoly
//             pvpoly uses vertical line from  testx, testy
//             pitri tests 3D point crosses a 3D triangle [0] [1] [2]
//             ptdat tests 3d point in .dat structure
// include after datread.h

int pnpoly(int nvert, float vertx[], float verty[], float testx, float testy);

int pvpoly(int nvert, float vertx[], float verty[], float testx, float testy);

int pitri(int nvert, float vertx[], float verty[], float vertz[],
	             float testx, float testy, float testz);

#ifndef DPTS
typedef struct {float x; float y; float z;} dpts;
#endif

int ptdat(int num_vert, int num_poly, dpts verts[], int polys[],
	  float testx, float testy, float testz);