bigbluebutton-Github/bbb-export-annotations/shapes/Oval.js

61 lines
1.8 KiB
JavaScript

import {Polygon as SVGPolygon} from '@svgdotjs/svg.js';
import {Geo} from './Geo.js';
import {TAU} from '../shapes/helpers.js';
/**
* Creates an SVG oval shape from Tldraw v2 JSON data.
*
* @class Oval
* @extends {Geo}
*/
export class Oval extends Geo {
/**
* Draws an oval shape on the SVG canvas.
* @return {G} Returns the SVG group element containing the oval.
* @see {@link https://github.com/tldraw/tldraw/blob/main/packages/editor/src/lib/primitives/geometry/Stadium2d.ts} Adapted from Tldraw.
*/
draw() {
const w = Math.max(1, this.w);
const h = Math.max(1, this.h + this.growY);
const cx = w / 2;
const cy = h / 2;
const len = 25; // Number of vertices to use for the oval
const points = Array(len * 2 - 2).fill(null).map(() => []);
if (h > w) {
for (let i = 0; i < len - 1; i++) {
const t1 = -(TAU / 2) + ((TAU / 2) * i) / (len - 2);
const t2 = ((TAU / 2) * i) / (len - 2);
points[i] = [cx + cx * Math.cos(t1), cx + cx * Math.sin(t1)];
points[i + (len - 1)] = [cx + cx * Math.cos(t2),
h - cx + cx * Math.sin(t2)];
}
} else {
for (let i = 0; i < len - 1; i++) {
const t1 = -(TAU / 4) + (TAU / 2 * i) / (len - 2);
const t2 = (TAU / 4) + (TAU / 2 * -i) / (len - 2);
points[i] = [w - cy + cy * Math.cos(t1), h - cy + cy * Math.sin(t1)];
points[i + (len - 1)] = [cy - cy * Math.cos(t2),
h - cy + cy * Math.sin(t2)];
}
}
const formattedPoints = points.map((p) => p.join(',')).join(' ');
const ovalGroup = this.shapeGroup;
const oval = new SVGPolygon({
'points': formattedPoints,
'stroke': this.shapeColor,
'stroke-width': this.thickness,
'style': this.dasharray,
});
this.setFill(oval);
ovalGroup.add(oval);
this.drawLabel(ovalGroup);
return ovalGroup;
}
}