atlas/web/_js/atlas.js
2022-04-28 02:44:46 -07:00

60 lines
No EOL
1.8 KiB
JavaScript

/*
========================================================================
The 2022 /r/place Atlas
An Atlas of Reddit's 2022 /r/place, with information to each
artwork of the canvas provided by the community.
Copyright (c) 2017 Roland Rytz <roland@draemm.li>
Copyright (c) 2022 Place Atlas contributors
Licensed under the GNU Affero General Public License Version 3
https://place-atlas.stefanocoding.me/license.txt
========================================================================
*/
window.addEventListener("error", function (e) {
console.error(e);
let errorMessage = "<h4 class=\"mb-3\">An error has occurred:</h4>";
errorMessage += "<p class=\"text-danger\">" + e.message + "</p>";
errorMessage += "<p class=\"text-danger\">on line " + e.lineno + "</p>";
errorMessage += "<p>If this keeps happening, feel free to tell us on <a href=\"https://discord.gg/pJkm23b2nA\">our Discord server</a>.</p>";
document.getElementById("loadingContent").innerHTML = errorMessage;
});
function getPositionOfEntry(entry) {
let startX = 2000, startY = 2000;
for (const [x, y] of entry.path) {
startX = Math.min(x, startX);
startY = Math.min(y, startY)
}
if (startX === 2000 || startY === 2000) return null;
return [parseInt(startX), parseInt(startY)];
}
const areaMap = new Map();
// Modified from https://stackoverflow.com/a/33670691
function calcPolygonArea(vertices) {
const hit = areaMap.get(vertices);
if (hit != null) {
return hit;
}
let total = 0;
for (let i = 0, l = vertices.length; i < l; i++) {
const addX = vertices[i][0];
const addY = vertices[i == vertices.length - 1 ? 0 : i + 1][1];
const subX = vertices[i == vertices.length - 1 ? 0 : i + 1][0];
const subY = vertices[i][1];
total += (addX * addY * 0.5);
total -= (subX * subY * 0.5);
}
const area = Math.floor(Math.abs(total));
areaMap.set(vertices, area);
return area;
}