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@@ -2,6 +2,8 @@
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* @author zz85 / http://www.lab4games.net/zz85/blog
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*/
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+import { Earcut } from './Earcut.js';
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+
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var ShapeUtils = {
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// calculate area of the contour polygon
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@@ -27,814 +29,6 @@ var ShapeUtils = {
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},
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- triangulate: function ( vertices, holeIndices ) {
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-
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- // Port from: https://github.com/mapbox/earcut (v2.1.2)
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-
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- function earcut( data, holeIndices, dim ) {
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-
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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 = [];
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-
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- if ( ! outerNode ) return triangles;
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-
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- var minX, minY, maxX, maxY, x, y, invSize;
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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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-
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- if ( data.length > 80 * dim ) {
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-
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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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-
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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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-
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- // minX, minY and invSize are later used to transform coords into integers for z-order calculation
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-
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- invSize = Math.max( maxX - minX, maxY - minY );
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- invSize = invSize !== 0 ? 1 / invSize : 0;
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-
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- }
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-
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- earcutLinked( outerNode, triangles, dim, minX, minY, invSize );
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-
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- return triangles;
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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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-
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- function linkedList( data, start, end, dim, clockwise ) {
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-
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- var i, last;
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-
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- if ( clockwise === ( signedArea( data, start, end, dim ) > 0 ) ) {
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-
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- for ( i = start; i < end; i += dim ) last = insertNode( i, data[ i ], data[ i + 1 ], last );
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-
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- } else {
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-
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- for ( i = end - dim; i >= start; i -= dim ) last = insertNode( i, data[ i ], data[ i + 1 ], last );
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-
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- }
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-
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- if ( last && equals( last, last.next ) ) {
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-
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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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-
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- return last;
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-
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- }
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-
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- // eliminate colinear or duplicate points
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-
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- function filterPoints( start, end ) {
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-
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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, again;
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-
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- do {
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-
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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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-
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- removeNode( p );
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- p = end = p.prev;
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- if ( p === p.next ) break;
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- again = true;
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-
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- } else {
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-
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- p = p.next;
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-
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- }
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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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-
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- // main ear slicing loop which triangulates a polygon (given as a linked list)
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-
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- function earcutLinked( ear, triangles, dim, minX, minY, invSize, pass ) {
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-
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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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-
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- if ( ! pass && invSize ) indexCurve( ear, minX, minY, invSize );
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-
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- var stop = ear, prev, next;
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-
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- // iterate through ears, slicing them one by one
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-
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- while ( ear.prev !== ear.next ) {
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-
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- prev = ear.prev;
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- next = ear.next;
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-
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- if ( invSize ? isEarHashed( ear, minX, minY, invSize ) : isEar( ear ) ) {
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-
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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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-
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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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-
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- if ( ear === stop ) {
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-
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- // try filtering points and slicing again
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-
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- if ( ! pass ) {
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-
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- earcutLinked( filterPoints( ear ), triangles, dim, minX, minY, invSize, 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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-
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- } else if ( pass === 1 ) {
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-
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- ear = cureLocalIntersections( ear, triangles, dim );
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- earcutLinked( ear, triangles, dim, minX, minY, invSize, 2 );
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-
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- // as a last resort, try splitting the remaining polygon into two
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-
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- } else if ( pass === 2 ) {
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-
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- splitEarcut( ear, triangles, dim, minX, minY, invSize );
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-
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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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-
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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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-
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- function isEar( ear ) {
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-
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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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-
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- if ( pointInTriangle( a.x, a.y, b.x, b.y, c.x, c.y, p.x, p.y ) && area( p.prev, p, p.next ) >= 0 ) {
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-
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- return false;
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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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-
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- return true;
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-
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- }
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-
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- function isEarHashed( ear, minX, minY, invSize ) {
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-
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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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-
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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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-
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- var minZ = zOrder( minTX, minTY, minX, minY, invSize ),
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- maxZ = zOrder( maxTX, maxTY, minX, minY, invSize );
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-
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- // first look for points inside the triangle in increasing z-order
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-
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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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-
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- if ( p !== ear.prev && 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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-
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- // then look for points in decreasing z-order
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-
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- p = ear.prevZ;
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-
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- while ( p && p.z >= minZ ) {
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-
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- if ( p !== ear.prev && 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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-
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- p = p.prevZ;
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-
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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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-
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- // go through all polygon nodes and cure small local self-intersections
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-
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- function cureLocalIntersections( start, triangles, dim ) {
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-
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- var p = start;
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-
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- do {
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-
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- var a = p.prev, 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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-
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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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- }
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-
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- p = p.next;
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-
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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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-
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- // try splitting polygon into two and triangulate them independently
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-
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- function splitEarcut( start, triangles, dim, minX, minY, invSize ) {
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-
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- // look for a valid diagonal that divides the polygon into two
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-
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- var a = start;
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-
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- do {
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-
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- var b = a.next.next;
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-
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- while ( b !== a.prev ) {
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-
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- if ( a.i !== b.i && isValidDiagonal( a, b ) ) {
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-
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- // split the polygon in two by the diagonal
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-
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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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-
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- a = filterPoints( a, a.next );
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- c = filterPoints( c, c.next );
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-
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- // run earcut on each half
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-
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- earcutLinked( a, triangles, dim, minX, minY, invSize );
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- earcutLinked( c, triangles, dim, minX, minY, invSize );
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- return;
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-
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- }
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-
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- b = b.next;
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-
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- }
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-
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- a = a.next;
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-
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- } while ( a !== start );
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-
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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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-
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- function eliminateHoles( data, holeIndices, outerNode, dim ) {
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-
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- var queue = [], i, len, start, end, list;
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-
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- for ( i = 0, len = holeIndices.length; i < len; i ++ ) {
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-
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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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-
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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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-
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- for ( i = 0; i < queue.length; i ++ ) {
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-
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- eliminateHole( queue[ i ], outerNode );
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- outerNode = filterPoints( outerNode, outerNode.next );
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-
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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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-
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- function compareX( a, b ) {
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-
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- return a.x - b.x;
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-
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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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-
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- function eliminateHole( hole, outerNode ) {
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-
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- outerNode = findHoleBridge( hole, outerNode );
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-
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- if ( outerNode ) {
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-
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- var b = splitPolygon( outerNode, hole );
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-
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- filterPoints( b, b.next );
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-
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- }
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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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-
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- function findHoleBridge( hole, outerNode ) {
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-
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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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-
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- do {
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-
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- if ( hy <= p.y && hy >= p.next.y && p.next.y !== p.y ) {
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-
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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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-
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- if ( x <= hx && x > qx ) {
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-
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- qx = x;
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-
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- if ( x === hx ) {
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-
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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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- }
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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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-
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- }
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-
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- p = p.next;
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-
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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
|
|
|
-
|
|
|
- var stop = m,
|
|
|
- mx = m.x,
|
|
|
- my = m.y,
|
|
|
- tanMin = Infinity,
|
|
|
- tan;
|
|
|
-
|
|
|
- p = m.next;
|
|
|
-
|
|
|
- while ( p !== stop ) {
|
|
|
-
|
|
|
- if ( hx >= p.x && p.x >= mx && hx !== p.x &&
|
|
|
- pointInTriangle( hy < my ? hx : qx, hy, mx, my, hy < my ? qx : hx, hy, p.x, p.y ) ) {
|
|
|
-
|
|
|
- tan = Math.abs( hy - p.y ) / ( hx - p.x ); // tangential
|
|
|
-
|
|
|
- if ( ( tan < tanMin || ( tan === tanMin && p.x > m.x ) ) && locallyInside( p, hole ) ) {
|
|
|
-
|
|
|
- m = p;
|
|
|
- tanMin = tan;
|
|
|
-
|
|
|
- }
|
|
|
-
|
|
|
- }
|
|
|
-
|
|
|
- p = p.next;
|
|
|
-
|
|
|
- }
|
|
|
-
|
|
|
- return m;
|
|
|
-
|
|
|
- }
|
|
|
-
|
|
|
- // interlink polygon nodes in z-order
|
|
|
-
|
|
|
- function indexCurve( start, minX, minY, invSize ) {
|
|
|
-
|
|
|
- var p = start;
|
|
|
-
|
|
|
- do {
|
|
|
-
|
|
|
- if ( p.z === null ) p.z = zOrder( p.x, p.y, minX, minY, invSize );
|
|
|
- p.prevZ = p.prev;
|
|
|
- p.nextZ = p.next;
|
|
|
- p = p.next;
|
|
|
-
|
|
|
- } while ( p !== start );
|
|
|
-
|
|
|
- p.prevZ.nextZ = null;
|
|
|
- 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 ) {
|
|
|
-
|
|
|
- var i, p, q, e, tail, numMerges, pSize, qSize, inSize = 1;
|
|
|
-
|
|
|
- do {
|
|
|
-
|
|
|
- p = list;
|
|
|
- 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 && ( qSize === 0 || ! q || 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;
|
|
|
-
|
|
|
- e.prevZ = tail;
|
|
|
- tail = e;
|
|
|
-
|
|
|
- }
|
|
|
-
|
|
|
- p = q;
|
|
|
-
|
|
|
- }
|
|
|
-
|
|
|
- tail.nextZ = null;
|
|
|
- inSize *= 2;
|
|
|
-
|
|
|
- } while ( numMerges > 1 );
|
|
|
-
|
|
|
- return list;
|
|
|
-
|
|
|
- }
|
|
|
-
|
|
|
- // z-order of a point given coords and inverse of the longer side of data bbox
|
|
|
-
|
|
|
- function zOrder( x, y, minX, minY, invSize ) {
|
|
|
-
|
|
|
- // coords are transformed into non-negative 15-bit integer range
|
|
|
-
|
|
|
- x = 32767 * ( x - minX ) * invSize;
|
|
|
- y = 32767 * ( y - minY ) * invSize;
|
|
|
-
|
|
|
- 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 ) {
|
|
|
-
|
|
|
- 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, ay, bx, by, cx, cy, px, py ) {
|
|
|
-
|
|
|
- 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, b ) {
|
|
|
-
|
|
|
- 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, q, r ) {
|
|
|
-
|
|
|
- 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, p2 ) {
|
|
|
-
|
|
|
- return p1.x === p2.x && p1.y === p2.y;
|
|
|
-
|
|
|
- }
|
|
|
-
|
|
|
- // check if two segments intersect
|
|
|
-
|
|
|
- function intersects( p1, q1, p2, q2 ) {
|
|
|
-
|
|
|
- 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, b ) {
|
|
|
-
|
|
|
- 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, b ) {
|
|
|
-
|
|
|
- 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, b ) {
|
|
|
-
|
|
|
- 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 ) ) && p.next.y !== p.y &&
|
|
|
- ( 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, b ) {
|
|
|
-
|
|
|
- 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, x, y, last ) {
|
|
|
-
|
|
|
- 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 ) {
|
|
|
-
|
|
|
- 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;
|
|
|
-
|
|
|
- }
|
|
|
-
|
|
|
- function Node( i, x, y ) {
|
|
|
-
|
|
|
- // vertice index in coordinates array
|
|
|
- this.i = i;
|
|
|
-
|
|
|
- // vertex coordinates
|
|
|
- this.x = x;
|
|
|
- this.y = y;
|
|
|
-
|
|
|
- // previous and next vertice nodes in a polygon ring
|
|
|
- this.prev = null;
|
|
|
- this.next = null;
|
|
|
-
|
|
|
- // z-order curve value
|
|
|
- this.z = null;
|
|
|
-
|
|
|
- // previous and next nodes in z-order
|
|
|
- this.prevZ = null;
|
|
|
- this.nextZ = null;
|
|
|
-
|
|
|
- // indicates whether this is a steiner point
|
|
|
- this.steiner = false;
|
|
|
-
|
|
|
- }
|
|
|
-
|
|
|
- function signedArea( data, start, end, dim ) {
|
|
|
-
|
|
|
- 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;
|
|
|
-
|
|
|
- }
|
|
|
-
|
|
|
- return earcut( vertices, holeIndices );
|
|
|
-
|
|
|
- },
|
|
|
-
|
|
|
triangulateShape: function ( contour, holes ) {
|
|
|
|
|
|
function removeDupEndPts( points ) {
|
|
|
@@ -882,7 +76,7 @@ var ShapeUtils = {
|
|
|
|
|
|
//
|
|
|
|
|
|
- var triangles = ShapeUtils.triangulate( vertices, holeIndices );
|
|
|
+ var triangles = Earcut.triangulate( vertices, holeIndices );
|
|
|
|
|
|
//
|
|
|
|
Mugen87