Справка Houdini на русском Nodes VOP nodes

To Polar VOP node

Converts cartesian coordinates to polar coordinates.

Given a cartesian (XYZ) position, this node outputs the U (latitude), V (longitude), and radial distance of the point relative to the origin.

This is equivalent to:

radius = sqrt(x*x + y*y + z*z);
     u = atan(y, x) + M_PI;
     v = acos(z/radius);

Parameters

Output space

How this node outputs the UV coordinates.

Unit

U and V coordinates are in the range [0, 1].

Radians

UV coordinates are in radians. U is in the range (0, 2*pi) while V is in the range (0, pi).

Degrees

UV coordinates are in degrees. U is in the range (0, 360) while V is in the range (0, 180).

See also

VOP nodes