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 CUBE_WIDTH = 1.0;
const LETTER_THICKNESS = 0.12;
const SMOOTHNESS = 0.02;

const C = CUBE_WIDTH;

fn letter_r_arc(p: vec3f, ra: f32, rb: f32) -> f32
{
    var pp = p.yxz;
    pp.x = abs(pp.x - C*0.2);
    pp.y += C*0.25;
    let h = vec3(0.0, C*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);
}

// Letter M Z+
fn letter_m(p: vec3f) -> f32 {
    var q = p.yxz;
    q.y *= -1.0;
    return min(
        min(
            segment(q, vec3(-C*0.45, -C*0.5, C), vec3(-C*0.45, C*0.5, C)),
            segment(q, vec3(-C*0.45, -C*0.5, C), vec3(0.0, 0.0, C))
        ),
        min(
            segment(q, vec3(0.0, 0.0, C), vec3(C*0.45, -C*0.5, C)),
            segment(q, vec3(C*0.45, -C*0.5, C), vec3(C*0.45, C*0.5, C))
        )
    );
}

// Letter A Z-
fn letter_a(p: vec3f) -> f32 {
    var q = p.zyx;
    q = vec3(-q.yx, q.z);

    return min(
        min(
            segment(q, vec3(0.0, -C*0.5, -C), vec3(-C*0.4, C*0.5, -C)),
            segment(q, vec3(0.0, -C*0.5, -C), vec3( C*0.4, C*0.5, -C))
        ),
        segment(q, vec3(-C*0.2, C*0.1, -C), vec3(C*0.2, C*0.1, -C))
    );
}

// Letter R Y+
fn letter_r(p: vec3f) -> f32 {
    var q = p;
    q.y *= -1.0;
    q.x -= C*0.15;
    return min(
        letter_r_arc(q.xzy - vec3(0.0, 0.0, C), C*0.3, LETTER_THICKNESS),
        min(
            segment(q, vec3(-C*0.4, C, C*0.5), vec3(-C*0.4, C, -C*0.5)),
            segment(q, vec3(-C*0.15, C, -C*0.1), vec3( C*0.15, C, -C*0.5))
        )
    );
}


// Letter T X+
fn letter_t(p: vec3f) -> f32 {
    return min(
        segment(p, vec3(C, 0.0, C*0.5), vec3(C, 0.0, -C*0.5)),
        segment(p, vec3(C, -C*0.4, C*0.5), vec3(C, C*0.4, C*0.5))
    );
}


// Letter I Z-
fn letter_i(p: vec3f) -> f32 {
    var q = p.yxz;
    q.x *= -1.0;
    return segment(q, vec3(-C, 0.0, C*0.5), vec3(-C, 0.0, -C*0.5));
}


// Letter N Y-
fn letter_n(p: vec3f) -> f32 {
    var q = p.xzy;
//    q.x *= -1.0;

    return min(
        segment(q, vec3(-C*0.4, -C, C*0.5), vec3(-C*0.4, -C, -C*0.5)),
        min(
            segment(q, vec3( C*0.4, -C, C*0.5), vec3( C*0.4, -C, -C*0.5)),
            segment(q, vec3( -C*0.4, -C, -C*0.5), vec3( C*0.4, -C, C*0.5))
        )
    );
}

fn sdf3d(p: vec3f) -> f32 {
    let cube = sdf_op_smooth_intersection(
        sdf3d_box(p, vec3(CUBE_WIDTH, CUBE_WIDTH, CUBE_WIDTH)), 
        sdf3d_sphere(p, CUBE_WIDTH * 1.40),
        SMOOTHNESS);
    let letter = min(
        min(letter_m(p), letter_a(p)), 
        min(min(letter_r(p), letter_t(p)), 
            min(letter_i(p), letter_n(p)))
    );
        
    return sdf_op_smooth_subtraction(letter, cube, SMOOTHNESS);
}