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@@ -1,670 +0,0 @@
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-// All the credit goes to this project and the guy who's behind it https://github.com/mapbox/earcut
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-// Huge respect for a such great lib.
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-// Earcut license:
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-// Copyright (c) 2016, Mapbox
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-//
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-// Permission to use, copy, modify, and/or distribute this software for any purpose
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-// with or without fee is hereby granted, provided that the above copyright notice
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-// and this permission notice appear in all copies.
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-//
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-// THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH
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-// REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
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-// FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT,
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-// INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS
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-// OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
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-// TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF
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-// THIS SOFTWARE.
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-module Earcut {
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- /**
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- * The fastest and smallest JavaScript polygon triangulation library for your WebGL apps
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- * @param data is a flat array of vertice coordinates like [x0, y0, x1, y1, x2, y2, ...].
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- * @param holeIndices is an array of hole indices if any (e.g. [5, 8] for a 12- vertice input would mean one hole with vertices 5–7 and another with 8–11).
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- * @param dim is the number of coordinates per vertice in the input array (2 by default).
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- */
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- export function earcut(data: number[], holeIndices: number[], dim: number): Array<number> {
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- dim = dim || 2;
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-
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- var hasHoles = holeIndices && holeIndices.length,
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- outerLen = hasHoles ? holeIndices[0] * dim : data.length,
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- outerNode = linkedList(data, 0, outerLen, dim, true),
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- triangles = new Array<number>();
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-
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- if (!outerNode) return triangles;
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-
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- var minX = 0, minY = 0, maxX, maxY, x, y, size = 0;
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-
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- if (hasHoles) outerNode = eliminateHoles(data, holeIndices, outerNode, dim);
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-
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- // if the shape is not too simple, we'll use z-order curve hash later; calculate polygon bbox
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- if (data.length > 80 * dim) {
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- minX = maxX = data[0];
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- minY = maxY = data[1];
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-
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- for (var i = dim; i < outerLen; i += dim) {
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- x = data[i];
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- y = data[i + 1];
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- if (x < minX) minX = x;
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- if (y < minY) minY = y;
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- if (x > maxX) maxX = x;
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- if (y > maxY) maxY = y;
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- }
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-
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- // minX, minY and size are later used to transform coords into integers for z-order calculation
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- size = Math.max(maxX - minX, maxY - minY);
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- }
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-
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- earcutLinked(outerNode, triangles, dim, minX, minY, size, 0);
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-
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- return triangles;
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- }
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-
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- class Node {
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- public prev: any = null;
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- public next: any = null;
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-
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- public z: any = null;
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- public prevZ: any = null;
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- public nextZ: any = null;
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-
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- public steiner: boolean = false;
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-
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- public constructor(public i: number, public x: number, public y: number) {
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- }
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- }
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-
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- // create a circular doubly linked list from polygon points in the specified winding order
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- function linkedList(data: number[], start: number, end: number, dim: number, clockwise: boolean): Node {
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- var i, last: Node | null = null;
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-
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- if (clockwise === (signedArea(data, start, end, dim) > 0)) {
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- for (i = start; i < end; i += dim) last = insertNode(i, data[i], data[i + 1], (<Node>last));
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- } else {
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- for (i = end - dim; i >= start; i -= dim) last = insertNode(i, data[i], data[i + 1], (<Node>last));
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- }
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-
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- if (last && equals(last, last.next)) {
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- removeNode(last);
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- last = last.next;
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- }
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-
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- return (<Node>last);
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- }
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-
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- // eliminate colinear or duplicate points
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- function filterPoints(start: Node, end?: Node) {
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- if (!start) return start;
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- if (!end) end = start;
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-
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- var p = start,
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- again;
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- do {
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- again = false;
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-
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- if (!p.steiner && (equals(p, p.next) || area(p.prev, p, p.next) === 0)) {
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- removeNode(p);
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- p = end = p.prev;
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- if (p === p.next) return undefined;
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- again = true;
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-
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- } else {
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- p = p.next;
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- }
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- } while (again || p !== end);
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-
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- return end;
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- }
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-
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- // main ear slicing loop which triangulates a polygon (given as a linked list)
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- function earcutLinked(ear: any, triangles: number[], dim: number, minX: number, minY: number, size: number, pass?: number) {
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- if (!ear) return;
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-
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- // interlink polygon nodes in z-order
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- if (!pass && size) indexCurve(ear, minX, minY, size);
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-
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- var stop = ear,
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- prev,
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- next;
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-
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- // iterate through ears, slicing them one by one
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- while (ear.prev !== ear.next) {
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- prev = ear.prev;
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- next = ear.next;
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-
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- if (size ? isEarHashed(ear, minX, minY, size) : isEar(ear)) {
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- // cut off the triangle
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- triangles.push(prev.i / dim);
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- triangles.push(ear.i / dim);
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- triangles.push(next.i / dim);
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-
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- removeNode(ear);
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-
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- // skipping the next vertice leads to less sliver triangles
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- ear = next.next;
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- stop = next.next;
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-
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- continue;
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- }
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-
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- ear = next;
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-
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- // if we looped through the whole remaining polygon and can't find any more ears
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- if (ear === stop) {
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- // try filtering points and slicing again
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- if (!pass) {
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- earcutLinked(filterPoints(ear, undefined), triangles, dim, minX, minY, size, 1);
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-
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- // if this didn't work, try curing all small self-intersections locally
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- } else if (pass === 1) {
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- ear = cureLocalIntersections(ear, triangles, dim);
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- earcutLinked(ear, triangles, dim, minX, minY, size, 2);
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-
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- // as a last resort, try splitting the remaining polygon into two
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- } else if (pass === 2) {
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- splitEarcut(ear, triangles, dim, minX, minY, size);
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- }
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-
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- break;
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- }
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- }
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- }
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-
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- // check whether a polygon node forms a valid ear with adjacent nodes
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- function isEar(ear: Node) {
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- var a = ear.prev,
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- b = ear,
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- c = ear.next;
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-
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- if (area(a, b, c) >= 0) return false; // reflex, can't be an ear
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-
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- // now make sure we don't have other points inside the potential ear
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- var p = ear.next.next;
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-
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- while (p !== ear.prev) {
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- if (pointInTriangle(a.x, a.y, b.x, b.y, c.x, c.y, p.x, p.y) &&
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- area(p.prev, p, p.next) >= 0) return false;
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- p = p.next;
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- }
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-
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- return true;
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- }
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-
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- function isEarHashed(ear: Node, minX: number, minY: number, size: number) {
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- var a = ear.prev,
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- b = ear,
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- c = ear.next;
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-
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- if (area(a, b, c) >= 0) return false; // reflex, can't be an ear
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-
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- // triangle bbox; min & max are calculated like this for speed
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- var minTX = a.x < b.x ? (a.x < c.x ? a.x : c.x) : (b.x < c.x ? b.x : c.x),
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- minTY = a.y < b.y ? (a.y < c.y ? a.y : c.y) : (b.y < c.y ? b.y : c.y),
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- maxTX = a.x > b.x ? (a.x > c.x ? a.x : c.x) : (b.x > c.x ? b.x : c.x),
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- maxTY = a.y > b.y ? (a.y > c.y ? a.y : c.y) : (b.y > c.y ? b.y : c.y);
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-
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- // z-order range for the current triangle bbox;
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- var minZ = zOrder(minTX, minTY, minX, minY, size),
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- maxZ = zOrder(maxTX, maxTY, minX, minY, size);
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-
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- // first look for points inside the triangle in increasing z-order
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- var p = ear.nextZ;
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-
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- while (p && p.z <= maxZ) {
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- if (p !== ear.prev &&
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- p !== ear.next &&
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- pointInTriangle(a.x, a.y, b.x, b.y, c.x, c.y, p.x, p.y) &&
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- area(p.prev, p, p.next) >= 0) return false;
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- p = p.nextZ;
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- }
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-
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- // then look for points in decreasing z-order
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- p = ear.prevZ;
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-
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- while (p && p.z >= minZ) {
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- if (p !== ear.prev &&
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- p !== ear.next &&
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- pointInTriangle(a.x, a.y, b.x, b.y, c.x, c.y, p.x, p.y) &&
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- area(p.prev, p, p.next) >= 0) return false;
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- p = p.prevZ;
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- }
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-
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- return true;
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- }
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-
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- // go through all polygon nodes and cure small local self-intersections
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- function cureLocalIntersections(start: Node, triangles: number[], dim: number) {
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- var p = start;
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- do {
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- var a = p.prev,
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- b = p.next.next;
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-
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- if (!equals(a, b) && intersects(a, p, p.next, b) && locallyInside(a, b) && locallyInside(b, a)) {
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-
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- triangles.push(a.i / dim);
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- triangles.push(p.i / dim);
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- triangles.push(b.i / dim);
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-
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- // remove two nodes involved
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- removeNode(p);
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- removeNode(p.next);
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-
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- p = start = b;
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- }
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- p = p.next;
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- } while (p !== start);
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-
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- return p;
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- }
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-
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- // try splitting polygon into two and triangulate them independently
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- function splitEarcut(start: Node, triangles: number[], dim: number, minX: number, minY: number, size: number) {
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- // look for a valid diagonal that divides the polygon into two
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- var a = start;
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- do {
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- var b = a.next.next;
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- while (b !== a.prev) {
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- if (a.i !== b.i && isValidDiagonal(a, b)) {
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- // split the polygon in two by the diagonal
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- var c = splitPolygon(a, b);
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-
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- // filter colinear points around the cuts
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- a = (<Node>filterPoints(a, a.next));
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- c = (<Node>filterPoints(c, c.next));
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-
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- // run earcut on each half
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- earcutLinked(a, triangles, dim, minX, minY, size, undefined);
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- earcutLinked(c, triangles, dim, minX, minY, size, undefined);
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- return;
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- }
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- b = b.next;
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- }
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- a = a.next;
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- } while (a !== start);
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- }
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-
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- // link every hole into the outer loop, producing a single-ring polygon without holes
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- function eliminateHoles(data: number[], holeIndices: number[], outerNode: Node, dim: number) {
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- var queue = [],
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- i,
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- len,
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- start,
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- end,
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- list;
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-
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- for (i = 0, len = holeIndices.length; i < len; i++) {
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- start = holeIndices[i] * dim;
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- end = i < len - 1 ? holeIndices[i + 1] * dim : data.length;
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- list = linkedList(data, start, end, dim, false);
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- if (list === list.next) list.steiner = true;
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- queue.push(getLeftmost(list));
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- }
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-
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- queue.sort(compareX);
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-
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- // process holes from left to right
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- for (i = 0; i < queue.length; i++) {
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- eliminateHole(queue[i], outerNode);
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- outerNode = (<Node>filterPoints(outerNode, outerNode.next));
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- }
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-
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- return outerNode;
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- }
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-
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- function compareX(a: Node, b: Node) {
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- return a.x - b.x;
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- }
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-
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- // find a bridge between vertices that connects hole with an outer ring and and link it
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- function eliminateHole(hole: Node, outerNode: Node) {
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- outerNode = (<Node>findHoleBridge(hole, outerNode));
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- if (outerNode) {
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- var b = splitPolygon(outerNode, hole);
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- filterPoints(b, b.next);
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- }
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- }
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-
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- // David Eberly's algorithm for finding a bridge between hole and outer polygon
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- function findHoleBridge(hole: Node, outerNode: Node) {
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- var p = outerNode,
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- hx = hole.x,
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- hy = hole.y,
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- qx = -Infinity,
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- m;
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-
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- // find a segment intersected by a ray from the hole's leftmost point to the left;
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- // segment's endpoint with lesser x will be potential connection point
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- do {
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- if (hy <= p.y && hy >= p.next.y) {
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- var x = p.x + (hy - p.y) * (p.next.x - p.x) / (p.next.y - p.y);
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- if (x <= hx && x > qx) {
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- qx = x;
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- if (x === hx) {
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- if (hy === p.y) return p;
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- if (hy === p.next.y) return p.next;
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- }
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- m = p.x < p.next.x ? p : p.next;
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- }
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- }
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- p = p.next;
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- } while (p !== outerNode);
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-
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- if (!m) return null;
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-
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- if (hx === qx) return m.prev; // hole touches outer segment; pick lower endpoint
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-
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- // look for points inside the triangle of hole point, segment intersection and endpoint;
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- // if there are no points found, we have a valid connection;
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- // otherwise choose the point of the minimum angle with the ray as connection point
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-
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- var stop = m,
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- mx = m.x,
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- my = m.y,
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- tanMin = Infinity,
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- tan;
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-
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- p = m.next;
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-
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- while (p !== stop) {
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- if (hx >= p.x &&
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- p.x >= mx &&
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- pointInTriangle(hy < my ? hx : qx, hy, mx, my, hy < my ? qx : hx, hy, p.x, p.y)) {
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-
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- tan = Math.abs(hy - p.y) / (hx - p.x); // tangential
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-
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- if ((tan < tanMin || (tan === tanMin && p.x > m.x)) && locallyInside(p, hole)) {
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- m = p;
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- tanMin = tan;
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- }
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- }
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-
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- p = p.next;
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- }
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-
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- return m;
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- }
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-
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- // interlink polygon nodes in z-order
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- function indexCurve(start: Node, minX: number, minY: number, size: number) {
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- var p = start;
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- do {
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- if (p.z === null) p.z = zOrder(p.x, p.y, minX, minY, size);
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- p.prevZ = p.prev;
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- p.nextZ = p.next;
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- p = p.next;
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- } while (p !== start);
|
|
|
-
|
|
|
- (<any>p.prevZ.nextZ) = null;
|
|
|
- (<any>p.prevZ) = null;
|
|
|
-
|
|
|
- sortLinked(p);
|
|
|
- }
|
|
|
-
|
|
|
- // Simon Tatham's linked list merge sort algorithm
|
|
|
- // http://www.chiark.greenend.org.uk/~sgtatham/algorithms/listsort.html
|
|
|
- function sortLinked(list: Node) {
|
|
|
- var i, p, q, e, tail, numMerges, pSize, qSize, inSize = 1;
|
|
|
- do {
|
|
|
- p = list;
|
|
|
- (<any>list) = null;
|
|
|
- tail = null;
|
|
|
- numMerges = 0;
|
|
|
-
|
|
|
- while (p) {
|
|
|
- numMerges++;
|
|
|
- q = p;
|
|
|
- pSize = 0;
|
|
|
- for (i = 0; i < inSize; i++) {
|
|
|
- pSize++;
|
|
|
- q = q.nextZ;
|
|
|
- if (!q) break;
|
|
|
- }
|
|
|
-
|
|
|
- qSize = inSize;
|
|
|
-
|
|
|
- while (pSize > 0 || (qSize > 0 && q)) {
|
|
|
-
|
|
|
- if (pSize === 0) {
|
|
|
- e = q;
|
|
|
- q = q.nextZ;
|
|
|
- qSize--;
|
|
|
- } else if (qSize === 0 || !q) {
|
|
|
- e = p;
|
|
|
- p = p.nextZ;
|
|
|
- pSize--;
|
|
|
- } else if (p.z <= q.z) {
|
|
|
- e = p;
|
|
|
- p = p.nextZ;
|
|
|
- pSize--;
|
|
|
- } else {
|
|
|
- e = q;
|
|
|
- q = q.nextZ;
|
|
|
- qSize--;
|
|
|
- }
|
|
|
-
|
|
|
- if (tail) tail.nextZ = e;
|
|
|
- else list = e;
|
|
|
-
|
|
|
- (<any>e.prevZ) = tail;
|
|
|
- tail = e;
|
|
|
- }
|
|
|
-
|
|
|
- p = q;
|
|
|
- }
|
|
|
-
|
|
|
- (<any>tail).nextZ = null;
|
|
|
- inSize *= 2;
|
|
|
-
|
|
|
- } while (numMerges > 1);
|
|
|
-
|
|
|
- return list;
|
|
|
- }
|
|
|
-
|
|
|
- // z-order of a point given coords and size of the data bounding box
|
|
|
- function zOrder(x: number, y: number, minX: number, minY: number, size: number) {
|
|
|
- // coords are transformed into non-negative 15-bit integer range
|
|
|
- x = 32767 * (x - minX) / size;
|
|
|
- y = 32767 * (y - minY) / size;
|
|
|
-
|
|
|
- x = (x | (x << 8)) & 0x00FF00FF;
|
|
|
- x = (x | (x << 4)) & 0x0F0F0F0F;
|
|
|
- x = (x | (x << 2)) & 0x33333333;
|
|
|
- x = (x | (x << 1)) & 0x55555555;
|
|
|
-
|
|
|
- y = (y | (y << 8)) & 0x00FF00FF;
|
|
|
- y = (y | (y << 4)) & 0x0F0F0F0F;
|
|
|
- y = (y | (y << 2)) & 0x33333333;
|
|
|
- y = (y | (y << 1)) & 0x55555555;
|
|
|
-
|
|
|
- return x | (y << 1);
|
|
|
- }
|
|
|
-
|
|
|
- // find the leftmost node of a polygon ring
|
|
|
- function getLeftmost(start: Node) {
|
|
|
- var p = start,
|
|
|
- leftmost = start;
|
|
|
- do {
|
|
|
- if (p.x < leftmost.x) leftmost = p;
|
|
|
- p = p.next;
|
|
|
- } while (p !== start);
|
|
|
-
|
|
|
- return leftmost;
|
|
|
- }
|
|
|
-
|
|
|
- // check if a point lies within a convex triangle
|
|
|
- function pointInTriangle(ax: number, ay: number, bx: number, by: number, cx: number, cy: number, px: number, py: number) {
|
|
|
- return (cx - px) * (ay - py) - (ax - px) * (cy - py) >= 0 &&
|
|
|
- (ax - px) * (by - py) - (bx - px) * (ay - py) >= 0 &&
|
|
|
- (bx - px) * (cy - py) - (cx - px) * (by - py) >= 0;
|
|
|
- }
|
|
|
-
|
|
|
- // check if a diagonal between two polygon nodes is valid (lies in polygon interior)
|
|
|
- function isValidDiagonal(a: Node, b: Node) {
|
|
|
- return a.next.i !== b.i &&
|
|
|
- a.prev.i !== b.i &&
|
|
|
- !intersectsPolygon(a, b) &&
|
|
|
- locallyInside(a, b) &&
|
|
|
- locallyInside(b, a) &&
|
|
|
- middleInside(a, b);
|
|
|
- }
|
|
|
-
|
|
|
- // signed area of a triangle
|
|
|
- function area(p: Node, q: Node, r: Node) {
|
|
|
- return (q.y - p.y) * (r.x - q.x) - (q.x - p.x) * (r.y - q.y);
|
|
|
- }
|
|
|
-
|
|
|
- // check if two points are equal
|
|
|
- function equals(p1: Node, p2: Node) {
|
|
|
- return p1.x === p2.x && p1.y === p2.y;
|
|
|
- }
|
|
|
-
|
|
|
- // check if two segments intersect
|
|
|
- function intersects(p1: Node, q1: Node, p2: Node, q2: Node) {
|
|
|
- if ((equals(p1, q1) && equals(p2, q2)) ||
|
|
|
- (equals(p1, q2) && equals(p2, q1))) return true;
|
|
|
- return area(p1, q1, p2) > 0 !== area(p1, q1, q2) > 0 &&
|
|
|
- area(p2, q2, p1) > 0 !== area(p2, q2, q1) > 0;
|
|
|
- }
|
|
|
-
|
|
|
- // check if a polygon diagonal intersects any polygon segments
|
|
|
- function intersectsPolygon(a: Node, b: Node) {
|
|
|
- var p = a;
|
|
|
- do {
|
|
|
- if (p.i !== a.i &&
|
|
|
- p.next.i !== a.i &&
|
|
|
- p.i !== b.i &&
|
|
|
- p.next.i !== b.i &&
|
|
|
- intersects(p, p.next, a, b)) return true;
|
|
|
- p = p.next;
|
|
|
- } while (p !== a);
|
|
|
-
|
|
|
- return false;
|
|
|
- }
|
|
|
-
|
|
|
- // check if a polygon diagonal is locally inside the polygon
|
|
|
- function locallyInside(a: Node, b: Node) {
|
|
|
- return area(a.prev, a, a.next) < 0
|
|
|
- ? area(a, b, a.next) >= 0 && area(a, a.prev, b) >= 0
|
|
|
- : area(a, b, a.prev) < 0 || area(a, a.next, b) < 0;
|
|
|
- }
|
|
|
-
|
|
|
- // check if the middle point of a polygon diagonal is inside the polygon
|
|
|
- function middleInside(a: Node, b: Node) {
|
|
|
- var p = a,
|
|
|
- inside = false,
|
|
|
- px = (a.x + b.x) / 2,
|
|
|
- py = (a.y + b.y) / 2;
|
|
|
- do {
|
|
|
- if (((p.y > py) !== (p.next.y > py)) && (px < (p.next.x - p.x) * (py - p.y) / (p.next.y - p.y) + p.x))
|
|
|
- inside = !inside;
|
|
|
- p = p.next;
|
|
|
- } while (p !== a);
|
|
|
-
|
|
|
- return inside;
|
|
|
- }
|
|
|
-
|
|
|
- // link two polygon vertices with a bridge; if the vertices belong to the same ring, it splits polygon into two;
|
|
|
- // if one belongs to the outer ring and another to a hole, it merges it into a single ring
|
|
|
- function splitPolygon(a: Node, b: Node) {
|
|
|
- var a2 = new Node(a.i, a.x, a.y),
|
|
|
- b2 = new Node(b.i, b.x, b.y),
|
|
|
- an = a.next,
|
|
|
- bp = b.prev;
|
|
|
-
|
|
|
- a.next = b;
|
|
|
- b.prev = a;
|
|
|
-
|
|
|
- a2.next = an;
|
|
|
- an.prev = a2;
|
|
|
-
|
|
|
- b2.next = a2;
|
|
|
- a2.prev = b2;
|
|
|
-
|
|
|
- bp.next = b2;
|
|
|
- b2.prev = bp;
|
|
|
-
|
|
|
- return b2;
|
|
|
- }
|
|
|
-
|
|
|
- // create a node and optionally link it with previous one (in a circular doubly linked list)
|
|
|
- function insertNode(i: number, x: number, y: number, last?: Node) {
|
|
|
- var p = new Node(i, x, y);
|
|
|
-
|
|
|
- if (!last) {
|
|
|
- p.prev = p;
|
|
|
- p.next = p;
|
|
|
-
|
|
|
- } else {
|
|
|
- p.next = last.next;
|
|
|
- p.prev = last;
|
|
|
- last.next.prev = p;
|
|
|
- last.next = p;
|
|
|
- }
|
|
|
- return p;
|
|
|
- }
|
|
|
-
|
|
|
- function removeNode(p: Node) {
|
|
|
- p.next.prev = p.prev;
|
|
|
- p.prev.next = p.next;
|
|
|
-
|
|
|
- if (p.prevZ) p.prevZ.nextZ = p.nextZ;
|
|
|
- if (p.nextZ) p.nextZ.prevZ = p.prevZ;
|
|
|
- }
|
|
|
-
|
|
|
- /**
|
|
|
- * return a percentage difference between the polygon area and its triangulation area;
|
|
|
- * used to verify correctness of triangulation
|
|
|
- */
|
|
|
- export function deviation(data: number[], holeIndices: number[], dim: number, triangles: number[]) {
|
|
|
- var hasHoles = holeIndices && holeIndices.length;
|
|
|
- var outerLen = hasHoles ? holeIndices[0] * dim : data.length;
|
|
|
-
|
|
|
- var polygonArea = Math.abs(signedArea(data, 0, outerLen, dim));
|
|
|
- if (hasHoles) {
|
|
|
- for (var i = 0, len = holeIndices.length; i < len; i++) {
|
|
|
- var start = holeIndices[i] * dim;
|
|
|
- var end = i < len - 1 ? holeIndices[i + 1] * dim : data.length;
|
|
|
- polygonArea -= Math.abs(signedArea(data, start, end, dim));
|
|
|
- }
|
|
|
- }
|
|
|
-
|
|
|
- var trianglesArea = 0;
|
|
|
- for (i = 0; i < triangles.length; i += 3) {
|
|
|
- var a = triangles[i] * dim;
|
|
|
- var b = triangles[i + 1] * dim;
|
|
|
- var c = triangles[i + 2] * dim;
|
|
|
- trianglesArea += Math.abs(
|
|
|
- (data[a] - data[c]) * (data[b + 1] - data[a + 1]) -
|
|
|
- (data[a] - data[b]) * (data[c + 1] - data[a + 1]));
|
|
|
- }
|
|
|
-
|
|
|
- return polygonArea === 0 && trianglesArea === 0 ? 0 : Math.abs((trianglesArea - polygonArea) / polygonArea);
|
|
|
- };
|
|
|
-
|
|
|
- function signedArea(data: number[], start: number, end: number, dim: number) {
|
|
|
- var sum = 0;
|
|
|
- for (var i = start, j = end - dim; i < end; i += dim) {
|
|
|
- sum += (data[j] - data[i]) * (data[i + 1] + data[j + 1]);
|
|
|
- j = i;
|
|
|
- }
|
|
|
- return sum;
|
|
|
- }
|
|
|
-
|
|
|
- /**
|
|
|
- * turn a polygon in a multi-dimensional array form (e.g. as in GeoJSON) into a form Earcut accepts
|
|
|
- */
|
|
|
- export function flatten(data: number[][][]) {
|
|
|
- var dim = data[0][0].length,
|
|
|
- result = { vertices: new Array<number>(), holes: new Array<number>(), dimensions: dim },
|
|
|
- holeIndex = 0;
|
|
|
-
|
|
|
- for (var i = 0; i < data.length; i++) {
|
|
|
- for (var j = 0; j < data[i].length; j++) {
|
|
|
- for (var d = 0; d < dim; d++) result.vertices.push(data[i][j][d]);
|
|
|
- }
|
|
|
- if (i > 0) {
|
|
|
- holeIndex += data[i - 1].length;
|
|
|
- result.holes.push(holeIndex);
|
|
|
- }
|
|
|
- }
|
|
|
- return result;
|
|
|
- };
|
|
|
-}
|
David Catuhe