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@@ -1,181 +0,0 @@
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-/**
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- * @author donmccurdy / https://www.donmccurdy.com/
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- */
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-
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-/**
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- * Utility class for sampling weighted random points on the surface of a mesh.
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- *
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- * Building the sampler is a one-time O(n) operation. Once built, any number of
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- * random samples may be selected in O(logn) time. Memory usage is O(n).
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- *
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- * References:
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- * - http://www.joesfer.com/?p=84
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- * - https://stackoverflow.com/a/4322940/1314762
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- */
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-THREE.MeshSurfaceSampler = ( function () {
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-
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- var _face = new THREE.Triangle();
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-
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- function MeshSurfaceSampler ( geometry ) {
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-
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- if ( ! geometry.isBufferGeometry || geometry.attributes.position.itemSize !== 3 ) {
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-
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- throw new Error( 'THREE.MeshSurfaceSampler: Requires BufferGeometry triangle mesh.' );
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-
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- }
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-
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- if ( geometry.index ) {
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-
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- console.warn( 'THREE.MeshSurfaceSampler: Converting geometry to non-indexed BufferGeometry.' );
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-
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- geometry = geometry.toNonIndexed();
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-
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- }
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-
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- this.geometry = geometry;
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-
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- this.positionAttribute = this.geometry.getAttribute( 'position' );
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- this.weightAttribute = null;
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-
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- this.distribution = null;
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-
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- };
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-
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- MeshSurfaceSampler.prototype = {
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-
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- constructor: MeshSurfaceSampler,
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-
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- setWeightAttribute: function ( name ) {
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-
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- this.weightAttribute = name ? this.geometry.getAttribute( name ) : null;
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-
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- return this;
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-
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- },
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-
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- build: function () {
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-
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- var positionAttribute = this.positionAttribute;
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- var weightAttribute = this.weightAttribute;
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-
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- var faceWeights = new Float32Array( positionAttribute.count / 3 );
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-
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- // Accumulate weights for each mesh face.
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-
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- for ( var i = 0; i < positionAttribute.count; i += 3 ) {
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-
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- var faceWeight = 1;
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-
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- if ( weightAttribute ) {
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-
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- faceWeight = weightAttribute.getX( i )
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- + weightAttribute.getX( i + 1 )
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- + weightAttribute.getX( i + 2 );
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-
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- }
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-
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- _face.a.fromBufferAttribute( positionAttribute, i );
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- _face.b.fromBufferAttribute( positionAttribute, i + 1 );
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- _face.c.fromBufferAttribute( positionAttribute, i + 2 );
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- faceWeight *= _face.getArea();
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-
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- faceWeights[ i / 3 ] = faceWeight;
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-
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- }
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-
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- // Store cumulative total face weights in an array, where weight index
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- // corresponds to face index.
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-
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- this.distribution = new Float32Array( positionAttribute.count / 3 );
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-
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- var cumulativeTotal = 0;
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-
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- for ( var i = 0; i < faceWeights.length; i ++ ) {
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-
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- cumulativeTotal += faceWeights[ i ];
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-
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- this.distribution[ i ] = cumulativeTotal;
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-
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- }
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-
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- return this;
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-
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- },
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-
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- sample: function ( targetPosition, targetNormal ) {
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-
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- var cumulativeTotal = this.distribution[ this.distribution.length - 1 ];
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-
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- var faceIndex = this.binarySearch( Math.random() * cumulativeTotal );
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-
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- return this.sampleFace( faceIndex, targetPosition, targetNormal );
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-
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- },
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-
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- binarySearch: function ( x ) {
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-
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- var dist = this.distribution;
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- var start = 0;
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- var end = dist.length - 1;
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-
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- var index = -1;
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-
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- while ( start <= end ) {
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-
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- var mid = Math.floor( ( start + end ) / 2 );
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-
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- if ( dist[ mid - 1 ] <= x && dist[ mid ] > x ) {
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-
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- index = mid;
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-
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- break;
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-
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- } else if ( x < dist[ mid ] ) {
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-
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- end = mid - 1;
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-
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- } else {
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-
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- start = mid + 1;
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-
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- }
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-
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- }
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-
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- return index;
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-
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- },
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-
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- sampleFace: function ( faceIndex, targetPosition, targetNormal ) {
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-
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- var u = Math.random();
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- var v = Math.random();
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-
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- if ( u + v > 1 ) {
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-
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- u = 1 - u;
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- v = 1 - v;
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-
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- }
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-
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- _face.a.fromBufferAttribute( this.positionAttribute, faceIndex * 3 );
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- _face.b.fromBufferAttribute( this.positionAttribute, faceIndex * 3 + 1 );
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- _face.c.fromBufferAttribute( this.positionAttribute, faceIndex * 3 + 2 );
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-
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- targetPosition
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- .set( 0, 0, 0 )
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- .addScaledVector( _face.a, u )
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- .addScaledVector( _face.b, v )
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- .addScaledVector( _face.c, 1 - ( u + v ) );
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-
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- _face.getNormal( targetNormal );
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-
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- return this;
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-
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- }
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-
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- };
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-
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- return MeshSurfaceSampler;
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-
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-} )();
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