# sf_thickenT

It thickens a surface with triangular mesh.

## Parameters

• `points` : A list of `[x, y, z]`s.
• `thickness` : The depth of the thickening.
• `triangles` : Determine which points are connected by an edge. All triangles have points in the same direction, counter-clockwise. If it's ignored, `sf_thickenT` would use `[x, y]` to do Delaunay trianglation.
• `direction` : The direction of thickening. It accepts `"BOTH"` (default), `"FORWARD"` or `"BACKWARD"`. Thickening is applied in both directions from the surface, the direction of the surface normals or the opposite direction to the surface normals. It also accept a direction vector `[x, y, z]`. Thickening is only applied in the direction you give.

## Examples

``````use <surface/sf_thickenT.scad>;

thickness = .2;

a_step = 15;
r_step = 0.2;

function f(x, y) = (y ^ 2 - x ^ 2) / 4;

points = [
for(a = [a_step:a_step:360], r = [r_step:r_step:2])
let(
x = r * cos(a),
y = r * sin(a)
)
[x, y, f(x, y)]
];

sf_thickenT(points, thickness);
``````

``````use <triangle/tri_delaunay.scad>;

u_step = 10;
v_step = 0.2;
thickness = .2;

points = [
for(u = [0:u_step:360], v = [-1:v_step:1])
let(
x = (1 + v / 2 * cos(u / 2)) * cos(u),
y = (1 + v / 2 * cos(u / 2)) * sin(u),
z = v / 2 * sin(u / 2)
)
[x, y, z]
];

triangles = tri_delaunay([
for(u = [0:u_step:360])
for(v = [-1:v_step:1])
[v, u]
]);

sf_thickenT(points, thickness, triangles);
``````