34 lines
1.1 KiB
JavaScript
34 lines
1.1 KiB
JavaScript
/**************************************************************
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* Spline curve
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**************************************************************/
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THREE.SplineCurve = function ( points /* array of Vector2 */ ) {
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this.points = ( points == undefined ) ? [] : points;
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};
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THREE.SplineCurve.prototype = Object.create( THREE.Curve.prototype );
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THREE.SplineCurve.prototype.constructor = THREE.SplineCurve;
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THREE.SplineCurve.prototype.getPoint = function ( t ) {
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var points = this.points;
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var point = ( points.length - 1 ) * t;
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var intPoint = Math.floor( point );
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var weight = point - intPoint;
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var point0 = points[ intPoint == 0 ? intPoint : intPoint - 1 ]
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var point1 = points[ intPoint ]
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var point2 = points[ intPoint > points.length - 2 ? points.length - 1 : intPoint + 1 ]
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var point3 = points[ intPoint > points.length - 3 ? points.length - 1 : intPoint + 2 ]
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var vector = new THREE.Vector2();
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vector.x = THREE.Curve.Utils.interpolate( point0.x, point1.x, point2.x, point3.x, weight );
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vector.y = THREE.Curve.Utils.interpolate( point0.y, point1.y, point2.y, point3.y, weight );
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return vector;
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};
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