1 files changed, 151 insertions, 0 deletions
diff --git a/web/static/dartboard.js b/web/static/dartboard.js
new file mode 100644
index 0000000..46e5c4c
--- /dev/null
+++ b/web/static/dartboard.js
@@ -0,0 +1,151 @@
+const diameter = 451.0;
+const dists = [7.13, 16.68, 97.06, 106.62, 159.66, 169.22];
+const wire_width = 1.56;
+const sectors = ['20', '1', '18', '4', '13', '6', '10', '15', '2', '17',
+	'3', '19', '7', '16', '8', '11', '14', '9', '12', '5'];
+
+const c_black = '#272b2c';
+const c_white = '#fbe3ba';
+const c_red = '#f6302f';
+const c_green = '#22912d';
+const c_wire = '#909ca0';
+const c_wire_inner = '#d8e6ec';
+
+const svgns = 'http://www.w3.org/2000/svg';
+
+function p2c(a, r) {
+	const t = a * Math.PI / 180;
+	return [r * Math.cos(t), r * Math.sin(t)];
+}
+
+function gen_arc(a1, a2, r1, r2, c) {
+	const [x1, y1] = p2c(a1 === a2 ? 1 : a2, r1);
+	const [x2, y2] = p2c(a1 === a2 ? 0 : a1, r1);
+	const [x3, y3] = p2c(a1 === a2 ? 0 : a1, r2);
+	const [x4, y4] = p2c(a1 === a2 ? 1 : a2, r2);
+
+	const elem = document.createElementNS(svgns, 'path');
+	elem.setAttribute('d',
+		`M${x1} ${y1}` +
+			`A${r1} ${r1} 0 0 0 ${x2} ${y2}` +
+			(a1 === a2 ? `A${r1} ${r1} 0 1 0 ${x1} ${y1}` : '') +
+			`L${x3} ${y3}` +
+			`A${r2} ${r2} 0 0 1 ${x4} ${y4}` +
+			(a1 === a2 ? `A${r2} ${r2} 0 1 1 ${x3} ${y3}` : '') +
+			'Z');
+	elem.setAttribute('fill', c)
+	return elem;
+}
+
+function gen_segment(a, r1, r2, c) {
+	return gen_arc(a - 9, a + 9, r1, r2, c);
+}
+
+function gen_ring(r, w, c) {
+	return gen_arc(0, 0, r - w/2, r + w/2, c);
+}
+
+function gen_circle(r, c) {
+	const elem = document.createElementNS(svgns, 'circle');
+	elem.setAttribute('r', r);
+	elem.setAttribute('fill', c)
+	return elem;
+}
+
+function gen_line(a, r1, r2, w, c) {
+	const [x1, y1] = p2c(a, r1);
+	const [x2, y2] = p2c(a, r2);
+
+	const elem = document.createElementNS(svgns, 'line');
+	elem.setAttribute('x1', x1);
+	elem.setAttribute('y1', y1);
+	elem.setAttribute('x2', x2);
+	elem.setAttribute('y2', y2);
+	elem.setAttribute('stroke', c);
+	elem.setAttribute('stroke-width', w);
+	return elem;
+}
+
+function draw_spider(board) {
+	for (let i = 5; i > 1; --i) {
+		board.appendChild(gen_ring(dists[i], wire_width, c_wire));
+		board.appendChild(gen_ring(dists[i], wire_width/2, c_wire_inner));
+	}
+
+	for (let i = 20; i > 0; --i) {
+		let a = 90 - (i * 18) - 9;
+		if (a < 0) a += 360;
+		board.appendChild(gen_line(a, dists[1], dists[5] + 10,
+			wire_width, c_wire));
+		board.appendChild(gen_line(a, dists[1], dists[5] + 10 - wire_width/4,
+			wire_width/2, c_wire_inner));
+	}
+
+	for (let i = 1; i >= 0; --i) {
+		board.appendChild(gen_ring(dists[i], wire_width, c_wire));
+		board.appendChild(gen_ring(dists[i], wire_width/2, c_wire_inner));
+	}
+}
+
+function draw_numbers(board) {
+	board.appendChild(gen_ring(diameter/2 - wire_width*4, wire_width, '#ddd'));
+
+	const r = diameter/2 - 33/2;
+	for (let i = 0; i < 20; ++i) {
+		let a = 90 - (i * 18);
+		if (a < 0) a += 360;
+		const [x, y] = p2c(a, r);
+
+		const elem = document.createElementNS(svgns, 'text');
+		elem.textContent = sectors[i];
+		elem.setAttribute('font-size', '33');
+		elem.setAttribute('fill',  '#fff');
+		elem.setAttribute('transform',  `scale(1 -1) translate(${x} ${-y}) ` +
+			`rotate(${a <= 180 ? 90 - a : 270 - a})`);
+		elem.setAttribute('text-anchor',  'middle');
+		elem.setAttribute('dominant-baseline',  'central');
+		board.appendChild(elem);
+	}
+}
+
+function draw_board() {
+	const board = document.getElementById('dartboard');
+	const points = document.getElementById('dartboard-points');
+
+	const r = diameter/2;
+	board.setAttribute('transform', `translate(${r} ${r}) scale(1 -1)`);
+	points.setAttribute('transform', `translate(${r} ${r}) scale(1 -1)`);
+	board.appendChild(gen_circle(r, c_black));
+
+	for (let i = 5; i > 1; --i) {
+		for (let j = 0; j < 20; ++j) {
+			let a = 90 - (j * 18);
+			if (a < 0) a += 360;
+
+			const elem = gen_segment(a, dists[i-1], dists[i],
+				i%2 ? (j%2 ? c_green : c_red) : (j%2 ? c_white : c_black));
+			board.appendChild(elem);
+		}
+	}
+
+	board.appendChild(gen_circle(dists[1], c_green));
+	board.appendChild(gen_circle(dists[0], c_red));
+	draw_spider(board);
+	draw_numbers(board);
+}
+
+function draw_point(x, y) {
+	const points = document.getElementById('dartboard-points');
+	elem = gen_circle(8, '#33f');
+	elem.setAttribute('cx', x);
+	elem.setAttribute('cy', y);
+	elem.setAttribute('stroke', '#ff0');
+	elem.setAttribute('stroke-width', '2');
+	points.appendChild(elem);
+}
+
+function clear_points() {
+	document.getElementById('dartboard-points').textContent = '';
+}
+
+document.addEventListener('DOMContentLoaded', () => draw_board());