1  /**
 2  * ptf_ring.scad
 3  *
 4  * @copyright Justin Lin, 2020
 5  * @license https://opensource.org/licenses/lgpl-3.0.html
 6  *
 7  * @see https://openhome.cc/eGossip/OpenSCAD/lib3x-ptf_ring.html
 8  *
 9  **/ 
10  
11  use <ptf_rotate.scad>
12  use <ptf_y_twist.scad>
13  
14  function ptf_ring(size, point, radius, angle = 360, twist = 0) = 
15      let(twisted = ptf_y_twist(size, point, twist))
16      ptf_rotate([radius + twisted.x, 0, twisted.z], angle / size.y * twisted.y);