fem_tutos/node_modules/d3-shape/src/symbol/triangle.js

import {sqrt} from "../math.js";

const sqrt3 = sqrt(3);

export default {
  draw(context, size) {
    const y = -sqrt(size / (sqrt3 * 3));
    context.moveTo(0, y * 2);
    context.lineTo(-sqrt3 * y, -y);
    context.lineTo(sqrt3 * y, -y);
    context.closePath();
  }
};