20 #define ZERO(x) ((x) < tolerance && (x) > -tolerance)
21 #define TOLERANCE 1.0e-10
46 double x1,
double y1,
double z1,
47 double x2,
double y2,
double z2,
int with_z,
48 double *px,
double *py,
double *pz,
52 register double dx, dy, dz;
53 register double dpx, dpy, dpz;
54 register double tpx, tpy, tpz;
79 t = (dx * (x - x1) + dy * (y - y1) + dz * (z - z1)) / (dx * dx +
114 *pdist = sqrt(dpx * dpx + dpy * dpy + dpz * dpz);
117 return (dx * dx + dy * dy + dz * dz);