diff --git a/src/main.rs b/src/main.rs
index fc04388..30446f7 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -10,6 +10,7 @@ mod handle;
 mod mesh;
 mod model;
 mod pool;
+mod procgen;
 mod renderer;
 mod scene;
 mod shader;
@@ -52,6 +53,78 @@ impl WorldState for Grid {
     }
 }
 
+struct Metaballs {
+    mesh: MeshInstance,
+}
+
+impl Metaballs {
+    fn new(mut ren: &mut Renderer) -> Self {
+        use procgen::marching_cubes::*;
+
+        let metaballs = vec![
+            glam::Vec3A::new(-5., -5., 2.),
+            glam::Vec3A::new(8., 0.0, -1.),
+            glam::Vec3A::new(1., 5., -3.),
+        ];
+
+        let field = |x: i32, y: i32, z: i32| {
+            let c = glam::Vec3A::new(x as f32, y as f32, z as f32);
+            let mut sum = 0.0;
+            for ball in metaballs.iter() {
+                sum += 1.0 / ball.distance(c);
+            }
+
+            sum - 0.4
+        };
+
+        let r = 20;
+        let domain = MarchDomain {
+            min: Vec3::new(-r, -r, -r),
+            max: Vec3::new(r, r, r),
+        };
+
+        let vertices = marching_cubes(field, &domain);
+        let vertices: Vec<mesh::Vertex> = vertices
+            .iter()
+            .map(|v| mesh::Vertex {
+                position: v.position.into(),
+                normal: v.normal.into(),
+                tex_coords: [0.0; 2],
+            })
+            .collect();
+
+        let indices = (0..(vertices.len() as u32)).collect();
+
+        let mesh_data = mesh::MeshData {
+            vertices, indices
+        };
+
+        let albedo_data = pool::TextureData {
+            width: 8,
+            height: 8,
+            data: vec![0xff; 256],
+        };
+
+        let mesh = ren.load_mesh(&mesh_data);
+        let albedo = ren.load_texture(&albedo_data);
+        let material = ren.load_material(&pool::MaterialData { albedo, metallic_roughness: albedo });
+
+        let mesh = scene::MeshInstance {
+            mesh, material, transform: glam::Mat4::IDENTITY,
+        };
+
+        Self { mesh }
+    }
+}
+
+impl WorldState for Metaballs {
+    fn update(&mut self) {}
+
+    fn render(&self) -> Vec<MeshInstance> {
+        vec![self.mesh]
+    }
+}
+
 struct Planet {
     speed: f32,
     offset: f32,
@@ -153,7 +226,8 @@ fn main() {
     let mut is_grabbed = false;
     let mut ren = pollster::block_on(make_window_renderer(&window));
     // let mut state: Box<dyn WorldState> = Box::new(Planets::new(&mut ren));
-    let mut state: Box<dyn WorldState> = Box::new(Grid::new(&mut ren));
+    // let mut state: Box<dyn WorldState> = Box::new(Grid::new(&mut ren));
+    let mut state: Box<dyn WorldState> = Box::new(Metaballs::new(&mut ren));
 
     let lights = vec![
         PointLight {
@@ -172,18 +246,26 @@ fn main() {
             center: glam::Vec3A::new(0.0, 5.0, -7.0),
             intensity: glam::Vec3A::new(0.0, 0.0, 100.0),
         },
+        PointLight {
+            center: glam::Vec3A::new(0.0, 50.0, 0.0),
+            intensity: glam::Vec3A::new(1000.0, 1000.0, 1000.0),
+        },
     ];
 
     event_loop.run(move |event, _, control_flow| match event {
         Event::RedrawRequested(_) => {
-            let scene = Scene { meshes: &state.render(), point_lights: &lights };
+            let scene = Scene {
+                meshes: &state.render(),
+                point_lights: &lights,
+            };
             match ren.render(&camera, &scene) {
                 Ok(_) => {}
                 Err(wgpu::SurfaceError::Lost) => ren.resize(ren.size),
                 Err(wgpu::SurfaceError::OutOfMemory) => *control_flow = ControlFlow::Exit,
+                Err(wgpu::SurfaceError::Timeout) => {}
                 Err(e) => println!("error: {:?}", e),
             };
-        },
+        }
         Event::MainEventsCleared => {
             camera.update();
             state.update();
diff --git a/src/procgen/marching_cubes.rs b/src/procgen/marching_cubes.rs
new file mode 100644
index 0000000..13be750
--- /dev/null
+++ b/src/procgen/marching_cubes.rs
@@ -0,0 +1,472 @@
+// Copyright (c) 2022 Marceline Cramer
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
+// largely based on http://paulbourke.net/geometry/polygonise/
+// TODO the Vec3 generic is pretty redundant, glam provides these types
+
+use std::collections::HashMap;
+
+#[derive(Copy, Clone, Debug, Eq, Hash, PartialEq)]
+pub struct Vec3<T> {
+    pub x: T,
+    pub y: T,
+    pub z: T,
+}
+
+impl<T: Copy> Vec3<T> {
+    pub fn new(x: T, y: T, z: T) -> Self {
+        Self { x, y, z }
+    }
+
+    pub fn to_array(&self) -> [T; 3] {
+        [self.x, self.y, self.z]
+    }
+}
+
+impl Vec3<f32> {
+    pub fn to_glam(self) -> glam::Vec3A {
+        glam::Vec3A::new(self.x, self.y, self.z)
+    }
+}
+
+impl From<Vec3<i32>> for Vec3<f32> {
+    fn from(other: Vec3<i32>) -> Self {
+        Self {
+            x: other.x as f32,
+            y: other.y as f32,
+            z: other.z as f32,
+        }
+    }
+}
+
+impl<T: Copy> From<Vec3<T>> for [T; 3] {
+    fn from(other: Vec3<T>) -> Self {
+        other.to_array()
+    }
+}
+
+#[derive(Copy, Clone, Debug, Hash)]
+pub struct MarchDomain {
+    pub min: Vec3<i32>,
+    pub max: Vec3<i32>,
+}
+
+#[derive(Copy, Clone, Debug)]
+pub struct Vertex {
+    pub position: Vec3<f32>,
+    pub normal: Vec3<f32>,
+}
+
+// TODO support a set of march domains
+// TODO use index buffer
+// TODO cache shared vertices using HashMap<Edge, Vec3<f32>>
+pub fn marching_cubes(
+    scalar_field: impl Fn(i32, i32, i32) -> f32,
+    domain: &MarchDomain,
+) -> Vec<Vertex> {
+    let samples = sample_corners(scalar_field, domain);
+
+    let test = |corner| samples[&corner] > 0.0;
+
+    // TODO this could be optimized using single-edge interpolation
+    // TODO improve with glam vector math
+    let interp = |cube: Vec3<i32>, edge_index| {
+        let (c1, c2) = edge_coords(cube, edge_index);
+        let v1 = samples[&c1];
+        let v2 = samples[&c2];
+        let p1: Vec3<f32> = c1.into();
+        let p2: Vec3<f32> = c2.into();
+        let mu = v1 / (v1 - v2);
+
+        Vec3 {
+            x: p1.x + mu * (p2.x - p1.x),
+            y: p1.y + mu * (p2.y - p1.y),
+            z: p1.z + mu * (p2.z - p1.z),
+        }
+    };
+
+    let mut vertices = Vec::new();
+    for x in domain.min.x..domain.max.x {
+        for y in domain.min.y..domain.max.y {
+            for z in domain.min.z..domain.max.z {
+                let cube = Vec3::new(x, y, z);
+                let index = configuration_index(cube, test);
+                let edges = CUBE_CONFIGURATIONS[index];
+
+                // TODO use Paul Bourke's edge table to share a cube's triangle vertices
+                let mut ntriangle = 0;
+                loop {
+                    let e1 = edges[ntriangle];
+                    if e1 < 0 {
+                        break;
+                    }
+
+                    let p1 = interp(cube, e1);
+                    let p2 = interp(cube, edges[ntriangle + 1]);
+                    let p3 = interp(cube, edges[ntriangle + 2]);
+
+                    let n = {
+                        let p1 = p1.to_glam();
+                        let p2 = p2.to_glam();
+                        let p3 = p3.to_glam();
+
+                        let n = (p2 - p1).cross(p3 - p1).normalize();
+
+                        Vec3 {
+                            x: n.x,
+                            y: n.y,
+                            z: n.z,
+                        }
+                    };
+
+                    let n1 = n;
+                    let n2 = n;
+                    let n3 = n;
+
+                    vertices.push(Vertex {
+                        position: p1,
+                        normal: n1,
+                    });
+                    vertices.push(Vertex {
+                        position: p2,
+                        normal: n2,
+                    });
+                    vertices.push(Vertex {
+                        position: p3,
+                        normal: n3,
+                    });
+
+                    ntriangle += 3;
+                }
+            }
+        }
+    }
+
+    vertices
+}
+
+fn sample_corners(
+    scalar_field: impl Fn(i32, i32, i32) -> f32,
+    domain: &MarchDomain,
+) -> HashMap<Vec3<i32>, f32> {
+    let mut samples = HashMap::new();
+
+    for x in domain.min.x..=domain.max.x {
+        for y in domain.min.y..=domain.max.y {
+            for z in domain.min.z..=domain.max.z {
+                let s = scalar_field(x, y, z);
+                let c = Vec3::new(x, y, z);
+                samples.insert(c, s);
+            }
+        }
+    }
+
+    samples
+}
+
+#[rustfmt::skip]
+fn corner_coords(cube: Vec3<i32>, corner_index: i8) -> Vec3<i32> {
+    match corner_index {
+        0 => cube,
+        1 => Vec3 { y: cube.y + 1, ..cube },
+        2 => Vec3 { x: cube.x + 1, y: cube.y + 1, ..cube },
+        3 => Vec3 { x: cube.x + 1, ..cube },
+        4 => Vec3 { z: cube.z + 1, ..cube },
+        5 => Vec3 { y: cube.y + 1, z: cube.z + 1, ..cube },
+        6 => Vec3 { x: cube.x + 1, y: cube.y + 1, z: cube.z + 1 },
+        7 => Vec3 { x: cube.x + 1, z: cube.z + 1, ..cube },
+        index => unreachable!("invalid corner index {}", index),
+    }
+}
+
+fn edge_coords(cube: Vec3<i32>, edge_index: i8) -> (Vec3<i32>, Vec3<i32>) {
+    let c = corner_coords;
+    match edge_index {
+        0 => (c(cube, 0), c(cube, 1)),
+        1 => (c(cube, 1), c(cube, 2)),
+        2 => (c(cube, 2), c(cube, 3)),
+        3 => (c(cube, 3), c(cube, 0)),
+        4 => (c(cube, 4), c(cube, 5)),
+        5 => (c(cube, 5), c(cube, 6)),
+        6 => (c(cube, 6), c(cube, 7)),
+        7 => (c(cube, 7), c(cube, 4)),
+        8 => (c(cube, 0), c(cube, 4)),
+        9 => (c(cube, 1), c(cube, 5)),
+        10 => (c(cube, 2), c(cube, 6)),
+        11 => (c(cube, 3), c(cube, 7)),
+        _ => unreachable!("invalid edge index"),
+    }
+}
+
+fn configuration_index(cube: Vec3<i32>, test: impl Fn(Vec3<i32>) -> bool) -> usize {
+    let s = |cube, corner| test(corner_coords(cube, corner)) as usize;
+    s(cube, 0)
+        | (s(cube, 1) << 1)
+        | (s(cube, 2) << 2)
+        | (s(cube, 3) << 3)
+        | (s(cube, 4) << 4)
+        | (s(cube, 5) << 5)
+        | (s(cube, 6) << 6)
+        | (s(cube, 7) << 7)
+}
+
+// source: http://paulbourke.net/geometry/polygonise/table2.txt
+#[rustfmt::skip]
+const CUBE_CONFIGURATIONS: [[i8; 13]; 256] = [
+    [-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1],
+    [ 8, 3, 0,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1],
+    [ 9, 0, 1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1],
+    [ 8, 3, 1, 8, 1, 9,-1,-1,-1,-1,-1,-1,-1],
+    [10, 1, 2,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1],
+    [ 8, 3, 0, 1, 2,10,-1,-1,-1,-1,-1,-1,-1],
+    [ 9, 0, 2, 9, 2,10,-1,-1,-1,-1,-1,-1,-1],
+    [ 3, 2, 8, 2,10, 8, 8,10, 9,-1,-1,-1,-1],
+    [11, 2, 3,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1],
+    [11, 2, 0,11, 0, 8,-1,-1,-1,-1,-1,-1,-1],
+    [11, 2, 3, 0, 1, 9,-1,-1,-1,-1,-1,-1,-1],
+    [ 2, 1,11, 1, 9,11,11, 9, 8,-1,-1,-1,-1],
+    [10, 1, 3,10, 3,11,-1,-1,-1,-1,-1,-1,-1],
+    [ 1, 0,10, 0, 8,10,10, 8,11,-1,-1,-1,-1],
+    [ 0, 3, 9, 3,11, 9, 9,11,10,-1,-1,-1,-1],
+    [ 8,10, 9, 8,11,10,-1,-1,-1,-1,-1,-1,-1],
+    [ 8, 4, 7,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1],
+    [ 3, 0, 4, 3, 4, 7,-1,-1,-1,-1,-1,-1,-1],
+    [ 1, 9, 0, 8, 4, 7,-1,-1,-1,-1,-1,-1,-1],
+    [ 9, 4, 1, 4, 7, 1, 1, 7, 3,-1,-1,-1,-1],
+    [10, 1, 2, 8, 4, 7,-1,-1,-1,-1,-1,-1,-1],
+    [ 2,10, 1, 0, 4, 7, 0, 7, 3,-1,-1,-1,-1],
+    [ 4, 7, 8, 0, 2,10, 0,10, 9,-1,-1,-1,-1],
+    [ 2, 7, 3, 2, 9, 7, 7, 9, 4, 2,10, 9,-1],
+    [ 2, 3,11, 7, 8, 4,-1,-1,-1,-1,-1,-1,-1],
+    [ 7,11, 4,11, 2, 4, 4, 2, 0,-1,-1,-1,-1],
+    [ 3,11, 2, 4, 7, 8, 9, 0, 1,-1,-1,-1,-1],
+    [ 2, 7,11, 2, 1, 7, 1, 4, 7, 1, 9, 4,-1],
+    [ 8, 4, 7,11,10, 1,11, 1, 3,-1,-1,-1,-1],
+    [11, 4, 7, 1, 4,11, 1,11,10, 1, 0, 4,-1],
+    [ 3, 8, 0, 7,11, 4,11, 9, 4,11,10, 9,-1],
+    [ 7,11, 4, 4,11, 9,11,10, 9,-1,-1,-1,-1],
+    [ 9, 5, 4,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1],
+    [ 3, 0, 8, 4, 9, 5,-1,-1,-1,-1,-1,-1,-1],
+    [ 5, 4, 0, 5, 0, 1,-1,-1,-1,-1,-1,-1,-1],
+    [ 4, 8, 5, 8, 3, 5, 5, 3, 1,-1,-1,-1,-1],
+    [ 2,10, 1, 9, 5, 4,-1,-1,-1,-1,-1,-1,-1],
+    [ 0, 8, 3, 5, 4, 9,10, 1, 2,-1,-1,-1,-1],
+    [10, 5, 2, 5, 4, 2, 2, 4, 0,-1,-1,-1,-1],
+    [ 3, 4, 8, 3, 2, 4, 2, 5, 4, 2,10, 5,-1],
+    [11, 2, 3, 9, 5, 4,-1,-1,-1,-1,-1,-1,-1],
+    [ 9, 5, 4, 8,11, 2, 8, 2, 0,-1,-1,-1,-1],
+    [ 3,11, 2, 1, 5, 4, 1, 4, 0,-1,-1,-1,-1],
+    [ 8, 5, 4, 2, 5, 8, 2, 8,11, 2, 1, 5,-1],
+    [ 5, 4, 9, 1, 3,11, 1,11,10,-1,-1,-1,-1],
+    [ 0, 9, 1, 4, 8, 5, 8,10, 5, 8,11,10,-1],
+    [ 3, 4, 0, 3,10, 4, 4,10, 5, 3,11,10,-1],
+    [ 4, 8, 5, 5, 8,10, 8,11,10,-1,-1,-1,-1],
+    [ 9, 5, 7, 9, 7, 8,-1,-1,-1,-1,-1,-1,-1],
+    [ 0, 9, 3, 9, 5, 3, 3, 5, 7,-1,-1,-1,-1],
+    [ 8, 0, 7, 0, 1, 7, 7, 1, 5,-1,-1,-1,-1],
+    [ 1, 7, 3, 1, 5, 7,-1,-1,-1,-1,-1,-1,-1],
+    [ 1, 2,10, 5, 7, 8, 5, 8, 9,-1,-1,-1,-1],
+    [ 9, 1, 0,10, 5, 2, 5, 3, 2, 5, 7, 3,-1],
+    [ 5, 2,10, 8, 2, 5, 8, 5, 7, 8, 0, 2,-1],
+    [10, 5, 2, 2, 5, 3, 5, 7, 3,-1,-1,-1,-1],
+    [11, 2, 3, 8, 9, 5, 8, 5, 7,-1,-1,-1,-1],
+    [ 9, 2, 0, 9, 7, 2, 2, 7,11, 9, 5, 7,-1],
+    [ 0, 3, 8, 2, 1,11, 1, 7,11, 1, 5, 7,-1],
+    [ 2, 1,11,11, 1, 7, 1, 5, 7,-1,-1,-1,-1],
+    [ 3, 9, 1, 3, 8, 9, 7,11,10, 7,10, 5,-1],
+    [ 9, 1, 0,10, 7,11,10, 5, 7,-1,-1,-1,-1],
+    [ 3, 8, 0, 7,10, 5, 7,11,10,-1,-1,-1,-1],
+    [11, 5, 7,11,10, 5,-1,-1,-1,-1,-1,-1,-1],
+    [10, 6, 5,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1],
+    [ 8, 3, 0,10, 6, 5,-1,-1,-1,-1,-1,-1,-1],
+    [ 0, 1, 9, 5,10, 6,-1,-1,-1,-1,-1,-1,-1],
+    [10, 6, 5, 9, 8, 3, 9, 3, 1,-1,-1,-1,-1],
+    [ 1, 2, 6, 1, 6, 5,-1,-1,-1,-1,-1,-1,-1],
+    [ 0, 8, 3, 2, 6, 5, 2, 5, 1,-1,-1,-1,-1],
+    [ 5, 9, 6, 9, 0, 6, 6, 0, 2,-1,-1,-1,-1],
+    [ 9, 6, 5, 3, 6, 9, 3, 9, 8, 3, 2, 6,-1],
+    [ 3,11, 2,10, 6, 5,-1,-1,-1,-1,-1,-1,-1],
+    [ 6, 5,10, 2, 0, 8, 2, 8,11,-1,-1,-1,-1],
+    [ 1, 9, 0, 6, 5,10,11, 2, 3,-1,-1,-1,-1],
+    [ 1,10, 2, 5, 9, 6, 9,11, 6, 9, 8,11,-1],
+    [11, 6, 3, 6, 5, 3, 3, 5, 1,-1,-1,-1,-1],
+    [ 0, 5, 1, 0,11, 5, 5,11, 6, 0, 8,11,-1],
+    [ 0, 5, 9, 0, 3, 5, 3, 6, 5, 3,11, 6,-1],
+    [ 5, 9, 6, 6, 9,11, 9, 8,11,-1,-1,-1,-1],
+    [10, 6, 5, 4, 7, 8,-1,-1,-1,-1,-1,-1,-1],
+    [ 5,10, 6, 7, 3, 0, 7, 0, 4,-1,-1,-1,-1],
+    [ 5,10, 6, 0, 1, 9, 8, 4, 7,-1,-1,-1,-1],
+    [ 4, 5, 9, 6, 7,10, 7, 1,10, 7, 3, 1,-1],
+    [ 7, 8, 4, 5, 1, 2, 5, 2, 6,-1,-1,-1,-1],
+    [ 4, 1, 0, 4, 5, 1, 6, 7, 3, 6, 3, 2,-1],
+    [ 9, 4, 5, 8, 0, 7, 0, 6, 7, 0, 2, 6,-1],
+    [ 4, 5, 9, 6, 3, 2, 6, 7, 3,-1,-1,-1,-1],
+    [ 7, 8, 4, 2, 3,11,10, 6, 5,-1,-1,-1,-1],
+    [11, 6, 7,10, 2, 5, 2, 4, 5, 2, 0, 4,-1],
+    [11, 6, 7, 8, 0, 3, 1,10, 2, 9, 4, 5,-1],
+    [ 6, 7,11, 1,10, 2, 9, 4, 5,-1,-1,-1,-1],
+    [ 6, 7,11, 4, 5, 8, 5, 3, 8, 5, 1, 3,-1],
+    [ 6, 7,11, 4, 1, 0, 4, 5, 1,-1,-1,-1,-1],
+    [ 4, 5, 9, 3, 8, 0,11, 6, 7,-1,-1,-1,-1],
+    [ 9, 4, 5, 7,11, 6,-1,-1,-1,-1,-1,-1,-1],
+    [10, 6, 4,10, 4, 9,-1,-1,-1,-1,-1,-1,-1],
+    [ 8, 3, 0, 9,10, 6, 9, 6, 4,-1,-1,-1,-1],
+    [ 1,10, 0,10, 6, 0, 0, 6, 4,-1,-1,-1,-1],
+    [ 8, 6, 4, 8, 1, 6, 6, 1,10, 8, 3, 1,-1],
+    [ 9, 1, 4, 1, 2, 4, 4, 2, 6,-1,-1,-1,-1],
+    [ 1, 0, 9, 3, 2, 8, 2, 4, 8, 2, 6, 4,-1],
+    [ 2, 4, 0, 2, 6, 4,-1,-1,-1,-1,-1,-1,-1],
+    [ 3, 2, 8, 8, 2, 4, 2, 6, 4,-1,-1,-1,-1],
+    [ 2, 3,11, 6, 4, 9, 6, 9,10,-1,-1,-1,-1],
+    [ 0,10, 2, 0, 9,10, 4, 8,11, 4,11, 6,-1],
+    [10, 2, 1,11, 6, 3, 6, 0, 3, 6, 4, 0,-1],
+    [10, 2, 1,11, 4, 8,11, 6, 4,-1,-1,-1,-1],
+    [ 1, 4, 9,11, 4, 1,11, 1, 3,11, 6, 4,-1],
+    [ 0, 9, 1, 4,11, 6, 4, 8,11,-1,-1,-1,-1],
+    [11, 6, 3, 3, 6, 0, 6, 4, 0,-1,-1,-1,-1],
+    [ 8, 6, 4, 8,11, 6,-1,-1,-1,-1,-1,-1,-1],
+    [ 6, 7,10, 7, 8,10,10, 8, 9,-1,-1,-1,-1],
+    [ 9, 3, 0, 6, 3, 9, 6, 9,10, 6, 7, 3,-1],
+    [ 6, 1,10, 6, 7, 1, 7, 0, 1, 7, 8, 0,-1],
+    [ 6, 7,10,10, 7, 1, 7, 3, 1,-1,-1,-1,-1],
+    [ 7, 2, 6, 7, 9, 2, 2, 9, 1, 7, 8, 9,-1],
+    [ 1, 0, 9, 3, 6, 7, 3, 2, 6,-1,-1,-1,-1],
+    [ 8, 0, 7, 7, 0, 6, 0, 2, 6,-1,-1,-1,-1],
+    [ 2, 7, 3, 2, 6, 7,-1,-1,-1,-1,-1,-1,-1],
+    [ 7,11, 6, 3, 8, 2, 8,10, 2, 8, 9,10,-1],
+    [11, 6, 7,10, 0, 9,10, 2, 0,-1,-1,-1,-1],
+    [ 2, 1,10, 7,11, 6, 8, 0, 3,-1,-1,-1,-1],
+    [ 1,10, 2, 6, 7,11,-1,-1,-1,-1,-1,-1,-1],
+    [ 7,11, 6, 3, 9, 1, 3, 8, 9,-1,-1,-1,-1],
+    [ 9, 1, 0,11, 6, 7,-1,-1,-1,-1,-1,-1,-1],
+    [ 0, 3, 8,11, 6, 7,-1,-1,-1,-1,-1,-1,-1],
+    [11, 6, 7,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1],
+    [11, 7, 6,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1],
+    [ 0, 8, 3,11, 7, 6,-1,-1,-1,-1,-1,-1,-1],
+    [ 9, 0, 1,11, 7, 6,-1,-1,-1,-1,-1,-1,-1],
+    [ 7, 6,11, 3, 1, 9, 3, 9, 8,-1,-1,-1,-1],
+    [ 1, 2,10, 6,11, 7,-1,-1,-1,-1,-1,-1,-1],
+    [ 2,10, 1, 7, 6,11, 8, 3, 0,-1,-1,-1,-1],
+    [11, 7, 6,10, 9, 0,10, 0, 2,-1,-1,-1,-1],
+    [ 7, 6,11, 3, 2, 8, 8, 2,10, 8,10, 9,-1],
+    [ 2, 3, 7, 2, 7, 6,-1,-1,-1,-1,-1,-1,-1],
+    [ 8, 7, 0, 7, 6, 0, 0, 6, 2,-1,-1,-1,-1],
+    [ 1, 9, 0, 3, 7, 6, 3, 6, 2,-1,-1,-1,-1],
+    [ 7, 6, 2, 7, 2, 9, 2, 1, 9, 7, 9, 8,-1],
+    [ 6,10, 7,10, 1, 7, 7, 1, 3,-1,-1,-1,-1],
+    [ 6,10, 1, 6, 1, 7, 7, 1, 0, 7, 0, 8,-1],
+    [ 9, 0, 3, 6, 9, 3, 6,10, 9, 6, 3, 7,-1],
+    [ 6,10, 7, 7,10, 8,10, 9, 8,-1,-1,-1,-1],
+    [ 8, 4, 6, 8, 6,11,-1,-1,-1,-1,-1,-1,-1],
+    [11, 3, 6, 3, 0, 6, 6, 0, 4,-1,-1,-1,-1],
+    [ 0, 1, 9, 4, 6,11, 4,11, 8,-1,-1,-1,-1],
+    [ 1, 9, 4,11, 1, 4,11, 3, 1,11, 4, 6,-1],
+    [10, 1, 2,11, 8, 4,11, 4, 6,-1,-1,-1,-1],
+    [10, 1, 2,11, 3, 6, 6, 3, 0, 6, 0, 4,-1],
+    [ 0, 2,10, 0,10, 9, 4,11, 8, 4, 6,11,-1],
+    [ 2,11, 3, 6, 9, 4, 6,10, 9,-1,-1,-1,-1],
+    [ 3, 8, 2, 8, 4, 2, 2, 4, 6,-1,-1,-1,-1],
+    [ 2, 0, 4, 2, 4, 6,-1,-1,-1,-1,-1,-1,-1],
+    [ 1, 9, 0, 3, 8, 2, 2, 8, 4, 2, 4, 6,-1],
+    [ 9, 4, 1, 1, 4, 2, 4, 6, 2,-1,-1,-1,-1],
+    [ 8, 4, 6, 8, 6, 1, 6,10, 1, 8, 1, 3,-1],
+    [ 1, 0,10,10, 0, 6, 0, 4, 6,-1,-1,-1,-1],
+    [ 8, 0, 3, 9, 6,10, 9, 4, 6,-1,-1,-1,-1],
+    [10, 4, 6,10, 9, 4,-1,-1,-1,-1,-1,-1,-1],
+    [ 9, 5, 4, 7, 6,11,-1,-1,-1,-1,-1,-1,-1],
+    [ 4, 9, 5, 3, 0, 8,11, 7, 6,-1,-1,-1,-1],
+    [ 6,11, 7, 4, 0, 1, 4, 1, 5,-1,-1,-1,-1],
+    [ 6,11, 7, 4, 8, 5, 5, 8, 3, 5, 3, 1,-1],
+    [ 6,11, 7, 1, 2,10, 9, 5, 4,-1,-1,-1,-1],
+    [11, 7, 6, 8, 3, 0, 1, 2,10, 9, 5, 4,-1],
+    [11, 7, 6,10, 5, 2, 2, 5, 4, 2, 4, 0,-1],
+    [ 7, 4, 8, 2,11, 3,10, 5, 6,-1,-1,-1,-1],
+    [ 4, 9, 5, 6, 2, 3, 6, 3, 7,-1,-1,-1,-1],
+    [ 9, 5, 4, 8, 7, 0, 0, 7, 6, 0, 6, 2,-1],
+    [ 4, 0, 1, 4, 1, 5, 6, 3, 7, 6, 2, 3,-1],
+    [ 7, 4, 8, 5, 2, 1, 5, 6, 2,-1,-1,-1,-1],
+    [ 4, 9, 5, 6,10, 7, 7,10, 1, 7, 1, 3,-1],
+    [ 5, 6,10, 0, 9, 1, 8, 7, 4,-1,-1,-1,-1],
+    [ 5, 6,10, 7, 0, 3, 7, 4, 0,-1,-1,-1,-1],
+    [10, 5, 6, 4, 8, 7,-1,-1,-1,-1,-1,-1,-1],
+    [ 5, 6, 9, 6,11, 9, 9,11, 8,-1,-1,-1,-1],
+    [ 0, 9, 5, 0, 5, 3, 3, 5, 6, 3, 6,11,-1],
+    [ 0, 1, 5, 0, 5,11, 5, 6,11, 0,11, 8,-1],
+    [11, 3, 6, 6, 3, 5, 3, 1, 5,-1,-1,-1,-1],
+    [ 1, 2,10, 5, 6, 9, 9, 6,11, 9,11, 8,-1],
+    [ 1, 0, 9, 6,10, 5,11, 3, 2,-1,-1,-1,-1],
+    [ 6,10, 5, 2, 8, 0, 2,11, 8,-1,-1,-1,-1],
+    [ 3, 2,11,10, 5, 6,-1,-1,-1,-1,-1,-1,-1],
+    [ 9, 5, 6, 3, 9, 6, 3, 8, 9, 3, 6, 2,-1],
+    [ 5, 6, 9, 9, 6, 0, 6, 2, 0,-1,-1,-1,-1],
+    [ 0, 3, 8, 2, 5, 6, 2, 1, 5,-1,-1,-1,-1],
+    [ 1, 6, 2, 1, 5, 6,-1,-1,-1,-1,-1,-1,-1],
+    [10, 5, 6, 9, 3, 8, 9, 1, 3,-1,-1,-1,-1],
+    [ 0, 9, 1, 5, 6,10,-1,-1,-1,-1,-1,-1,-1],
+    [ 8, 0, 3,10, 5, 6,-1,-1,-1,-1,-1,-1,-1],
+    [10, 5, 6,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1],
+    [11, 7, 5,11, 5,10,-1,-1,-1,-1,-1,-1,-1],
+    [ 3, 0, 8, 7, 5,10, 7,10,11,-1,-1,-1,-1],
+    [ 9, 0, 1,10,11, 7,10, 7, 5,-1,-1,-1,-1],
+    [ 3, 1, 9, 3, 9, 8, 7,10,11, 7, 5,10,-1],
+    [ 2,11, 1,11, 7, 1, 1, 7, 5,-1,-1,-1,-1],
+    [ 0, 8, 3, 2,11, 1, 1,11, 7, 1, 7, 5,-1],
+    [ 9, 0, 2, 9, 2, 7, 2,11, 7, 9, 7, 5,-1],
+    [11, 3, 2, 8, 5, 9, 8, 7, 5,-1,-1,-1,-1],
+    [10, 2, 5, 2, 3, 5, 5, 3, 7,-1,-1,-1,-1],
+    [ 5,10, 2, 8, 5, 2, 8, 7, 5, 8, 2, 0,-1],
+    [ 9, 0, 1,10, 2, 5, 5, 2, 3, 5, 3, 7,-1],
+    [ 1,10, 2, 5, 8, 7, 5, 9, 8,-1,-1,-1,-1],
+    [ 1, 3, 7, 1, 7, 5,-1,-1,-1,-1,-1,-1,-1],
+    [ 8, 7, 0, 0, 7, 1, 7, 5, 1,-1,-1,-1,-1],
+    [ 0, 3, 9, 9, 3, 5, 3, 7, 5,-1,-1,-1,-1],
+    [ 9, 7, 5, 9, 8, 7,-1,-1,-1,-1,-1,-1,-1],
+    [ 4, 5, 8, 5,10, 8, 8,10,11,-1,-1,-1,-1],
+    [ 3, 0, 4, 3, 4,10, 4, 5,10, 3,10,11,-1],
+    [ 0, 1, 9, 4, 5, 8, 8, 5,10, 8,10,11,-1],
+    [ 5, 9, 4, 1,11, 3, 1,10,11,-1,-1,-1,-1],
+    [ 8, 4, 5, 2, 8, 5, 2,11, 8, 2, 5, 1,-1],
+    [ 3, 2,11, 1, 4, 5, 1, 0, 4,-1,-1,-1,-1],
+    [ 9, 4, 5, 8, 2,11, 8, 0, 2,-1,-1,-1,-1],
+    [11, 3, 2, 9, 4, 5,-1,-1,-1,-1,-1,-1,-1],
+    [ 3, 8, 4, 3, 4, 2, 2, 4, 5, 2, 5,10,-1],
+    [10, 2, 5, 5, 2, 4, 2, 0, 4,-1,-1,-1,-1],
+    [ 0, 3, 8, 5, 9, 4,10, 2, 1,-1,-1,-1,-1],
+    [ 2, 1,10, 9, 4, 5,-1,-1,-1,-1,-1,-1,-1],
+    [ 4, 5, 8, 8, 5, 3, 5, 1, 3,-1,-1,-1,-1],
+    [ 5, 0, 4, 5, 1, 0,-1,-1,-1,-1,-1,-1,-1],
+    [ 3, 8, 0, 4, 5, 9,-1,-1,-1,-1,-1,-1,-1],
+    [ 9, 4, 5,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1],
+    [ 7, 4,11, 4, 9,11,11, 9,10,-1,-1,-1,-1],
+    [ 3, 0, 8, 7, 4,11,11, 4, 9,11, 9,10,-1],
+    [11, 7, 4, 1,11, 4, 1,10,11, 1, 4, 0,-1],
+    [ 8, 7, 4,11, 1,10,11, 3, 1,-1,-1,-1,-1],
+    [ 2,11, 7, 2, 7, 1, 1, 7, 4, 1, 4, 9,-1],
+    [ 3, 2,11, 4, 8, 7, 9, 1, 0,-1,-1,-1,-1],
+    [ 7, 4,11,11, 4, 2, 4, 0, 2,-1,-1,-1,-1],
+    [ 2,11, 3, 7, 4, 8,-1,-1,-1,-1,-1,-1,-1],
+    [ 2, 3, 7, 2, 7, 9, 7, 4, 9, 2, 9,10,-1],
+    [ 4, 8, 7, 0,10, 2, 0, 9,10,-1,-1,-1,-1],
+    [ 2, 1,10, 0, 7, 4, 0, 3, 7,-1,-1,-1,-1],
+    [10, 2, 1, 8, 7, 4,-1,-1,-1,-1,-1,-1,-1],
+    [ 9, 1, 4, 4, 1, 7, 1, 3, 7,-1,-1,-1,-1],
+    [ 1, 0, 9, 8, 7, 4,-1,-1,-1,-1,-1,-1,-1],
+    [ 3, 4, 0, 3, 7, 4,-1,-1,-1,-1,-1,-1,-1],
+    [ 8, 7, 4,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1],
+    [ 8, 9,10, 8,10,11,-1,-1,-1,-1,-1,-1,-1],
+    [ 0, 9, 3, 3, 9,11, 9,10,11,-1,-1,-1,-1],
+    [ 1,10, 0, 0,10, 8,10,11, 8,-1,-1,-1,-1],
+    [10, 3, 1,10,11, 3,-1,-1,-1,-1,-1,-1,-1],
+    [ 2,11, 1, 1,11, 9,11, 8, 9,-1,-1,-1,-1],
+    [11, 3, 2, 0, 9, 1,-1,-1,-1,-1,-1,-1,-1],
+    [11, 0, 2,11, 8, 0,-1,-1,-1,-1,-1,-1,-1],
+    [11, 3, 2,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1],
+    [ 3, 8, 2, 2, 8,10, 8, 9,10,-1,-1,-1,-1],
+    [ 9, 2, 0, 9,10, 2,-1,-1,-1,-1,-1,-1,-1],
+    [ 8, 0, 3, 1,10, 2,-1,-1,-1,-1,-1,-1,-1],
+    [10, 2, 1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1],
+    [ 8, 1, 3, 8, 9, 1,-1,-1,-1,-1,-1,-1,-1],
+    [ 9, 1, 0,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1],
+    [ 8, 0, 3,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1],
+    [-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1]
+];
diff --git a/src/procgen/mod.rs b/src/procgen/mod.rs
new file mode 100644
index 0000000..f8caeb8
--- /dev/null
+++ b/src/procgen/mod.rs
@@ -0,0 +1 @@
+pub mod marching_cubes;