Doodle3D-Slicer/three.js-master/examples/js/curves/NURBSSurface.js
2017-06-22 13:21:07 +02:00

50 lines
1.3 KiB
JavaScript
Executable File

/**
* @author renej
* NURBS surface object
*
* Implementation is based on (x, y [, z=0 [, w=1]]) control points with w=weight.
*
**/
/**************************************************************
* NURBS surface
**************************************************************/
THREE.NURBSSurface = function ( degree1, degree2, knots1, knots2 /* arrays of reals */, controlPoints /* array^2 of Vector(2|3|4) */) {
this.degree1 = degree1;
this.degree2 = degree2;
this.knots1 = knots1;
this.knots2 = knots2;
this.controlPoints = [];
var len1 = knots1.length - degree1 - 1;
var len2 = knots2.length - degree2 - 1;
// ensure Vector4 for control points
for (var i = 0; i < len1; ++ i) {
this.controlPoints[i] = []
for (var j = 0; j < len2; ++ j) {
var point = controlPoints[i][j];
this.controlPoints[i][j] = new THREE.Vector4(point.x, point.y, point.z, point.w);
}
}
};
THREE.NURBSSurface.prototype = {
constructor: THREE.NURBSSurface,
getPoint: function ( t1, t2 ) {
var u = this.knots1[0] + t1 * (this.knots1[this.knots1.length - 1] - this.knots1[0]); // linear mapping t1->u
var v = this.knots2[0] + t2 * (this.knots2[this.knots2.length - 1] - this.knots2[0]); // linear mapping t2->u
return THREE.NURBSUtils.calcSurfacePoint(this.degree1, this.degree2, this.knots1, this.knots2, this.controlPoints, u, v);
}
};