dotSCAD/docs/lib3x-tri_ear_clipping.md

tri_ear_clipping

Given a 2D shape. This function performs a polygon triangulation based on Ear clipping.

Since: 3.0

Parameters

• shape_pts : The shape points.
• ret : The type of returned data. Default to "TRI_INDICES" which returns the indices of the shape_pts. If "TRI_SHAPES" is given, return triangle shapes.
• epsilon : An upper bound on the relative error due to rounding in floating point arithmetic. Default to 0.0001.

Examples

use <triangle/tri_ear_clipping.scad> 

shape = [
    [0, 0],
    [10, 0],
    [12, 5],
    [5, 10],
    [10, 15],
    [0, 20],
    [-5, 18],
    [-18, 3],
    [-4, 10]
];

all_indices = tri_ear_clipping(shape);

for(tri_indices = all_indices) {
    offset(-.1)
        polygon([for(i = tri_indices) shape[i]]);
}

use <triangle/tri_ear_clipping.scad> 

shape = [
    [0, 0],
    [10, 0],
    [12, 5],
    [5, 10],
    [10, 15],
    [0, 20],
    [-5, 18],
    [-18, 3],
    [-4, 10]
];

tris = tri_ear_clipping(shape, ret = "TRI_SHAPES");

for(tri = tris) {
    offset(-.1)
        polygon(tri);
}