chijin/
chijin.rs

1//! Build a chijin (hand drum from Amami Oshima) with colors, boolean ops, and SVG export.
2
3use cadrum::{Color, Compound, DVec3, Edge, ProfileOrient, Solid};
4use std::f64::consts::PI;
5
6pub fn chijin() -> Result<Solid, cadrum::Error> {
7	// ── Body (cylinder): r=15, h=8, centered at origin (z=-4..+4) ────────
8	let cylinder = Solid::cylinder(15.0, DVec3::Z, 8.0)
9		.translate(DVec3::Z * -4.0)
10		.color("#999");
11
12	// ── Sheet: closed polygon in the XZ plane (y=0), swept 360° around Z
13	// により面と縁を一体で生成する。Face::from_polygon + Face::revolve の置換版:
14	//   - Edge::polygon は最後の点 → 最初の点を自動補完して閉じる
15	//   - spine は Z 軸まわりの円。半径によらずプロファイルを Z 周りに純粋回転
16	//     させるだけなので任意の正の値で可
17	//   - ProfileOrient::Up(Z) でプロファイルの上方向を Z 固定 → 回転(revolve)と等価
18	let cross_section = Edge::polygon(&[
19		DVec3::new(0.0, 0.0, 5.0),
20		DVec3::new(15.0, 0.0, 5.0),
21		DVec3::new(17.0, 0.0, 3.0),
22		DVec3::new(15.0, 0.0, 4.0),
23		DVec3::new(0.0, 0.0, 4.0),
24	])?;
25	let spine = Edge::circle(1.0, DVec3::Z)?;
26	let sheet = Solid::sweep(&cross_section, &[spine], ProfileOrient::Up(DVec3::Z))?
27		.color("#fff");
28	let sheets = [sheet.clone().mirror(DVec3::ZERO, DVec3::Z), sheet];
29
30	// ── Lacing blocks: 2x8x1, rotated 60° around Z, placed at y=15 ──────
31	let block_proto = Solid::cube(2.0, 8.0, 1.0)
32		.translate(DVec3::new(-1.0, -4.0, -0.5))
33		.rotate_z(60.0_f64.to_radians())
34		.translate(DVec3::Y * 15.0);
35
36	// ── Lacing holes: thin cylinders through each block ──────────────────
37	let hole_proto = Solid::cylinder(0.7, DVec3::X * 10.0 + DVec3::Z * 30.0, 30.0)
38		.translate(DVec3::new(-5.0, 16.0, -15.0));
39
40	// Distribute N blocks and holes evenly around Z, each block in a rainbow color
41	// N 個のブロックと穴を Z 軸周りに等間隔配置、各ブロックに虹色を割り当て
42	const N: usize = 20;
43	let angle = |i: usize| 2.0 * PI * (i as f64) / (N as f64);
44	let color = |i: usize| Color::from_hsv(i as f32 / N as f32, 1.0, 1.0);
45	let blocks: [Solid; N] = std::array::from_fn(|i| block_proto.clone().rotate_z(angle(i)).color(color(i)));
46	let holes: [Solid; N] = std::array::from_fn(|i| hole_proto.clone().rotate_z(angle(i)));
47	// ── Assemble with boolean operations: union, subtract, union ─────────
48	let result = [cylinder]
49		.union(&sheets)?
50		.subtract(&holes)?
51		.union(&blocks)?;
52	assert!(result.len() == 1);
53	Ok(result.into_iter().next().unwrap())
54}
55
56fn main() -> Result<(), cadrum::Error> {
57	let example_name = std::path::Path::new(file!()).file_stem().unwrap().to_str().unwrap();
58	let result = [chijin()?];
59
60	let mut f = std::fs::File::create(format!("{example_name}.step")).expect("failed to create STEP file");
61	cadrum::write_step(&result, &mut f).expect("failed to write STEP");
62
63	let mut f = std::fs::File::create(format!("{example_name}.svg")).expect("failed to create SVG file");
64	cadrum::mesh(&result, 0.5).and_then(|m| m.write_svg(DVec3::ONE, DVec3::Z, true, false, &mut f)).expect("failed to write SVG");
65
66	println!("wrote {example_name}.step / {example_name}.svg");
67	Ok(())
68}
chijin/chijin.rs

chijin/
chijin.rs
