atlas/web/_js/main/atlas.js
2023-03-26 15:16:03 +07:00

60 lines
No EOL
1.9 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 = canvasSize.x, startY = canvasSize.y
for (const [x, y] of entry.path) {
startX = Math.min(x, startX)
startY = Math.min(y, startY)
}
if (startX === canvasSize.x || startY === canvasSize.y) 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
}