arc.ts

import { equiv } from "@thi.ng/equiv";
import type {
	Attribs,
	IHiccupPathSegment,
	IHiccupShape,
} from "@thi.ng/geom-api";
import {
	pointAt as arcPointAt,
	pointAtTheta as arcPointAtTheta,
} from "@thi.ng/geom-arc/point-at";
import type { Vec } from "@thi.ng/vectors";
import { set } from "@thi.ng/vectors/set";
import { __copyAttribs } from "../internal/copy.js";

export class Arc implements IHiccupShape, IHiccupPathSegment {
	constructor(
		public pos: Vec,
		public r: Vec,
		public axis: number,
		public start: number,
		public end: number,
		public xl = false,
		public cw = false,
		public attribs?: Attribs
	) {}

	get type() {
		return "arc";
	}

	copy(): Arc {
		return new Arc(
			set([], this.pos),
			set([], this.r),
			this.axis,
			this.start,
			this.end,
			this.xl,
			this.cw,
			__copyAttribs(this)
		);
	}

	withAttribs(attribs: Attribs): Arc {
		return new Arc(
			this.pos,
			this.r,
			this.axis,
			this.start,
			this.end,
			this.xl,
			this.cw,
			attribs
		);
	}

	equiv(o: any) {
		return (
			o instanceof Arc &&
			equiv(this.pos, o.pos) &&
			equiv(this.r, o.r) &&
			this.start === o.start &&
			this.end === o.end &&
			this.axis === o.axis &&
			this.xl === o.xl &&
			this.cw &&
			o.cw
		);
	}

	pointAt(t: number, out: Vec = []) {
		return arcPointAt(
			this.pos,
			this.r,
			this.axis,
			this.start,
			this.end,
			t,
			out
		);
	}

	pointAtTheta(theta: number, out: Vec = []) {
		return arcPointAtTheta(this.pos, this.r, this.axis, theta, out);
	}

	toHiccup() {
		return [
			"path",
			this.attribs,
			[["M", this.pointAt(0)], ...this.toHiccupPathSegments()],
		];
	}

	toHiccupPathSegments() {
		return [
			[
				"A",
				this.r[0],
				this.r[1],
				this.axis,
				this.xl,
				this.cw,
				this.pointAt(1),
			],
		];
	}
}