dotSCAD/docs/lib2x-polytransversals.md

polytransversals

Crosscutting a polyline at different points gets several transversals. This module can operate reversely. It uses transversals to construct a polyline. For example, imagine that you have the following transversals:

This module can use them to construct the polyline:

When using this module, you should use points to represent each transversal.

You can view it as a better polyline2d module. If you have only the points of a path, using polyline2d or hull_polyline2d is a simple solution. If you know the transversals along a path, you can use polytransversals to get a better polyline.

Parameters

• transversals : A list of transversals. Each transversal is represented by a list of points. See the example below.

Examples

use <rotate_p.scad>;
use <polytransversals.scad>;
use <hull_polyline2d.scad>;

r = 35;    
tran_pts = [[-5, 0], [0, 5], [5, 0]];

trans = [
    for(a = [0:10:120])
        [
            for(p = tran_pts) 
                rotate_p(p, [0, 0, a]) + [r * cos(a), r * sin(a)]
        ]
];

polytransversals(trans);

#for(tran = trans) {
    hull_polyline2d(tran, 0.5);
}