source: other-projects/playing-in-the-street/summer-2013/trunk/Playing-in-the-Street-WPF/Content/Web/mrdoob-three.js-4862f5f/src/extras/curves/ClosedSplineCurve3.js@ 28897

/**************************************************************
 *  Closed Spline 3D curve
 **************************************************************/


THREE.ClosedSplineCurve3 = THREE.Curve.create(

    function ( points /* array of Vector3 */) {

        this.points = (points == undefined) ? [] : points;

    },

    function ( t ) {

        var v = new THREE.Vector3();
        var c = [];
        var points = this.points, point, intPoint, weight;
        point = ( points.length - 0 ) * t;
            // This needs to be from 0-length +1

        intPoint = Math.floor( point );
        weight = point - intPoint;

        intPoint += intPoint > 0 ? 0 : ( Math.floor( Math.abs( intPoint ) / points.length ) + 1 ) * points.length;
        c[ 0 ] = ( intPoint - 1 ) % points.length;
        c[ 1 ] = ( intPoint ) % points.length;
        c[ 2 ] = ( intPoint + 1 ) % points.length;
        c[ 3 ] = ( intPoint + 2 ) % points.length;

        v.x = THREE.Curve.Utils.interpolate( points[ c[ 0 ] ].x, points[ c[ 1 ] ].x, points[ c[ 2 ] ].x, points[ c[ 3 ] ].x, weight );
        v.y = THREE.Curve.Utils.interpolate( points[ c[ 0 ] ].y, points[ c[ 1 ] ].y, points[ c[ 2 ] ].y, points[ c[ 3 ] ].y, weight );
        v.z = THREE.Curve.Utils.interpolate( points[ c[ 0 ] ].z, points[ c[ 1 ] ].z, points[ c[ 2 ] ].z, points[ c[ 3 ] ].z, weight );

        return v;

    }

);