Rotational extrusion spins a 2D shape around the Z-axis. It's similar to the built-in
rotate_extrude; however, it supports
Because we cannot retrieve the shape points of built-in 2D modules, it's necessary to provide
If your 2D shape is not solid, indexes of triangles are required. See sweep for details.
shape_pts: A list of points represent a shape. See the example below.
radius: The circle radius.
angle: Defaults to 360. Specifies the number of degrees to sweep, starting at the positive X axis. It also accepts a 2 element vector which defines the central angle. The first element of the vector is the beginning angle in degrees, and the second element is the ending angle.
twist: The number of degrees of through which the shape is twisted.
scale: Scales the 2D shape by this value over the length of the extrusion. Scale can be a scalar or a vector.
"HOLLOW"or user-defined indexes. See sweep for details.
$fn: Check the circle module for more details.
use <ring_extrude.scad>; shape_pts = [ [2, -10], [2, 10], [-2, 10], [-2, -10] ]; ring_extrude(shape_pts, radius = 50, twist = 180);
use <ring_extrude.scad>; shape_pts = [ [2, -10], [2, 10], [-2, 10], [-2, -10] ]; ring_extrude(shape_pts, radius = 50, angle = 180, scale = 2);