diff --git a/src/crown_gear.rs b/src/crown_gear.rs
index 1cfe93a..364adc1 100644
--- a/src/crown_gear.rs
+++ b/src/crown_gear.rs
@@ -7,73 +7,77 @@ use crate::{
 	render::mesh::{CpuMeshIndexed, Vertex},
 };
 
-pub struct CrownGear {
+#[derive(Debug, Clone, Copy)]
+pub struct CrownGearDesc {
 	pub profile: Profile,
 	pub pitch_radius: f32,
+}
 
+#[derive(Debug, Clone, Copy)]
+pub struct CrownGearVisual {
 	pub inner_radius: f32,
 	pub outer_radius: f32,
 	pub base_thickness: f32,
 }
 
-impl CrownGear {
-	pub fn make_mesh(&self, sides: usize, color: Vec3) -> CpuMeshIndexed {
-		let teeth = 2.0 * self.pitch_radius;
-		let inner_scale = self.inner_radius / self.pitch_radius;
-		let outer_scale = self.outer_radius / self.pitch_radius;
+pub fn make_mesh(
+	desc: &CrownGearDesc,
+	visual: &CrownGearVisual,
+	sides: usize,
+	color: Vec3,
+) -> CpuMeshIndexed {
+	let teeth = 2.0 * desc.pitch_radius;
+	let inner_scale = visual.inner_radius / desc.pitch_radius;
+	let outer_scale = visual.outer_radius / desc.pitch_radius;
 
-		let mut mesh = CpuMeshIndexed::new();
-		mesh.vertices.reserve_exact(8 * sides);
-		mesh.faces.reserve_exact(8 * sides);
-		for k in 0..sides {
-			let t = k as f32 / sides as f32;
-			let rot = Mat3A::from_rotation_z(2.0 * PI * t);
+	let mut mesh = CpuMeshIndexed::new();
+	mesh.vertices.reserve_exact(8 * sides);
+	mesh.faces.reserve_exact(8 * sides);
+	for k in 0..sides {
+		let t = k as f32 / sides as f32;
+		let rot = Mat3A::from_rotation_z(2.0 * PI * t);
 
-			let tooth = t * teeth;
-			let y = self.profile.y_from_tooth(tooth);
+		let tooth = t * teeth;
+		let y = desc.profile.y_from_tooth(tooth);
 
-			let n_top = {
-				let eps = 1e-3;
-				let dy_dt = teeth
-					* (self.profile.y_from_tooth(tooth + eps)
-						- self.profile.y_from_tooth(tooth - eps))
-					/ (2.0 * eps);
-				vec3(-2.0 * PI * y, -dy_dt, 2.0 * PI * self.pitch_radius)
-			};
+		let n_top = {
+			let eps = 1e-3;
+			let dy_dt = teeth
+				* (desc.profile.y_from_tooth(tooth + eps) - desc.profile.y_from_tooth(tooth - eps))
+				/ (2.0 * eps);
+			vec3(-2.0 * PI * y, -dy_dt, 2.0 * PI * desc.pitch_radius)
+		};
 
-			let vertex = |x, z, n| Vertex {
-				position: rot * vec3(x, 0.0, z),
-				color,
-				normal: n,
-			};
-			mesh.vertices.extend([
-				// top
-				vertex(self.outer_radius, outer_scale * y, n_top),
-				vertex(self.inner_radius, inner_scale * y, n_top),
-				// bottom
-				vertex(self.inner_radius, -self.base_thickness, -Vec3::Z),
-				vertex(self.outer_radius, -self.base_thickness, -Vec3::Z),
-				// inner
-				vertex(self.inner_radius, inner_scale * y, -Vec3::X),
-				vertex(self.inner_radius, -self.base_thickness, -Vec3::X),
-				// outer
-				vertex(self.outer_radius, -self.base_thickness, Vec3::X),
-				vertex(self.outer_radius, outer_scale * y, Vec3::X),
-			]);
+		let vertex = |x, z, n| Vertex {
+			position: rot * vec3(x, 0.0, z),
+			color,
+			normal: n,
+		};
+		mesh.vertices.extend([
+			// top
+			vertex(visual.outer_radius, outer_scale * y, n_top),
+			vertex(visual.inner_radius, inner_scale * y, n_top),
+			// bottom
+			vertex(visual.inner_radius, -visual.base_thickness, -Vec3::Z),
+			vertex(visual.outer_radius, -visual.base_thickness, -Vec3::Z),
+			// inner
+			vertex(visual.inner_radius, inner_scale * y, -Vec3::X),
+			vertex(visual.inner_radius, -visual.base_thickness, -Vec3::X),
+			// outer
+			vertex(visual.outer_radius, -visual.base_thickness, Vec3::X),
+			vertex(visual.outer_radius, outer_scale * y, Vec3::X),
+		]);
 
-			let base1 = 8 * k;
-			let base2 = 8 * ((k + 1) % sides);
-			for j in 0..4 {
-				let j1 = 2 * j;
-				let j2 = 2 * j + 1;
-				mesh.faces.push(
-					[base1 + j1, base2 + j1, base1 + j2].map(|index| index.try_into().unwrap()),
-				);
-				mesh.faces.push(
-					[base2 + j2, base1 + j2, base2 + j1].map(|index| index.try_into().unwrap()),
-				);
-			}
+		let base1 = 8 * k;
+		let base2 = 8 * ((k + 1) % sides);
+		for j in 0..4 {
+			let j1 = 2 * j;
+			let j2 = 2 * j + 1;
+			mesh.faces
+				.push([base1 + j1, base2 + j1, base1 + j2].map(|index| index.try_into().unwrap()));
+			mesh.faces
+				.push([base2 + j2, base1 + j2, base2 + j1].map(|index| index.try_into().unwrap()));
 		}
-		mesh
 	}
+	mesh
 }
diff --git a/src/lib.rs b/src/lib.rs
index 100daa0..1eae7df 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -80,14 +80,19 @@ impl Core {
 
 		let depth = Self::create_depth_buffer(&device, pixel_size);
 		let mesh_pipeline = render::mesh::Pipeline::new(&device);
-		let crown_gear_mesh = crown_gear::CrownGear {
-			profile: Default::default(),
-			pitch_radius: 24.0,
-			inner_radius: 16.0,
-			outer_radius: 30.0,
-			base_thickness: 2.0,
-		}
-		.make_mesh(600, vec3(0.5, 0.5, 0.5));
+		let crown_gear_mesh = crown_gear::make_mesh(
+			&crown_gear::CrownGearDesc {
+				profile: Default::default(),
+				pitch_radius: 24.0,
+			},
+			&crown_gear::CrownGearVisual {
+				inner_radius: 16.0,
+				outer_radius: 30.0,
+				base_thickness: 2.0,
+			},
+			600,
+			vec3(0.5, 0.5, 0.5),
+		);
 		let mesh_gray = render::mesh::GpuMeshIndexed::new(&device, &crown_gear_mesh);
 
 		Self::configure_surface(&surface, &device, pixel_size);