sdf2mesh 0.1.0

A tool to convert SDFs to triangle meshes using wgpu and dual contouring
Documentation 
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use sdf3d::*;
use sdf::op;

const KEY_SIZE = 15.0;
const KEY_ELEVATION = 2.0;
const PLATE_HEIGHT = 1.5;
const LETTER_THICKNESS = 1.0;

fn letter_p_arc(p: vec3f, ra: f32, rb: f32) -> f32
{
    var pp = p.yxz;
    pp.x = abs(pp.x - KEY_SIZE*0.2);
    pp.y += KEY_SIZE*0.25;
    let h = vec3(0.0, KEY_SIZE*0.15, 0.0);
    let q = pp - clamp( pp, -h, h );
    let sc = vec2(1.0, 0.0);

    var k = 0.0;
    if (0.0 > sc.x*q.y) {
        k = dot(q.xy,sc);
    } else {
        k = length(q.xy);
    }

    return sqrt(dot(q,q) + ra*ra - 2.0*ra*k) - rb;
}

fn segment(p: vec3f, a: vec3f, b: vec3f) -> f32 {
    return sdf3d_capsule(p, a, b, LETTER_THICKNESS);
}

fn letter_p(p: vec3f) -> f32 {
    var q = p;
    q.y *= -1.0;
    q.x -= KEY_SIZE*0.15;
    return min(
        letter_p_arc(q.xzy, KEY_SIZE*0.3, LETTER_THICKNESS),
        segment(q, vec3(-KEY_SIZE*0.4, 0.0, KEY_SIZE*0.5), vec3(-KEY_SIZE*0.4, 0.0, -KEY_SIZE*0.5))
    );
}

fn sdf3d(p: vec3f) -> f32 {
    return sdf_op_smooth_subtraction(
        letter_p(p.xzy * 2.5 - vec3(0.0, KEY_ELEVATION * 2.5 + LETTER_THICKNESS, 0.0)),
        sdf_op_smooth_union(
            sdf3d_box(p, vec3(KEY_SIZE, KEY_SIZE, PLATE_HEIGHT)),
            sdf3d_cylinder(p.yzx - vec3(0.0, (KEY_ELEVATION + PLATE_HEIGHT) * 0.5, 0.0), KEY_ELEVATION - PLATE_HEIGHT, KEY_SIZE * 0.35),
            KEY_SIZE * 0.15
        ),
        0.0
    );
}