@xeokit/xeokit-sdk
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3D BIM IFC Viewer SDK for AEC engineering applications. Open Source JavaScript Toolkit based on pure WebGL for top performance, real-world coordinates and full double precision
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JavaScript
import {Curve} from "./Curve.js"
import {math} from "../math/math.js";
/**
* @desc A {@link Curve} along which a 3D position can be animated.
*
* * As shown in the diagram below, a CubicBezierCurve is defined by four control points.
* * You can sample a {@link CubicBezierCurve#point} and a {@link CubicBezierCurve#tangent} vector on a CubicBezierCurve for any given value of {@link CubicBezierCurve#t} in the range [0..1].
* * When you set {@link CubicBezierCurve#t} on a CubicBezierCurve, its {@link CubicBezierCurve#point} and {@link CubicBezierCurve#tangent} properties will update accordingly.
* * To build a complex path, you can combine an unlimited combination of CubicBezierCurves, {@link QuadraticBezierCurve}s and {@link SplineCurve}s into a {@link Path}.
*
* <br>
* <img style="border:1px solid;" src="https://upload.wikimedia.org/wikipedia/commons/thumb/d/db/B%C3%A9zier_3_big.gif/240px-B%C3%A9zier_3_big.gif"/>
* <br>
* [Cubic Bezier Curve from WikiPedia](https://en.wikipedia.org/wiki/B%C3%A9zier_curve)
*/
class CubicBezierCurve extends Curve {
/**
* @constructor
* @param {Component} [owner] Owner component. When destroyed, the owner will destroy this CubicBezierCurve as well.
* @param {*} [cfg] Configs
* @param {String} [cfg.id] Optional ID, unique among all components in the parent {@link Scene}, generated automatically when omitted.
* @param {Number[]} [cfg.v0=[0,0,0]] The starting point.
* @param {Number[]} [cfg.v1=[0,0,0]] The first control point.
* @param {Number[]} [cfg.v2=[0,0,0]] The middle control point.
* @param {Number[]} [cfg.v3=[0,0,0]] The ending point.
* @param {Number} [cfg.t=0] Current position on this CubicBezierCurve, in range between 0..1.
*/
constructor(owner, cfg = {}) {
super(owner, cfg);
this.v0 = cfg.v0;
this.v1 = cfg.v1;
this.v2 = cfg.v2;
this.v3 = cfg.v3;
this.t = cfg.t;
}
/**
* Sets the starting point on this CubicBezierCurve.
*
* Default value is ````[0.0, 0.0, 0.0]````
*
* @param {Number[]} value The starting point.
*/
set v0(value) {
this._v0 = value || math.vec3([0, 0, 0]);
}
/**
* Gets the starting point on this CubicBezierCurve.
*
* Default value is ````[0.0, 0.0, 0.0]````
*
* @returns {Number[]} The starting point.
*/
get v0() {
return this._v0;
}
/**
* Sets the first control point on this CubicBezierCurve.
*
* Default value is ````[0.0, 0.0, 0.0]````
*
* @param {Number[]} value The first control point.
*/
set v1(value) {
this._v1 = value || math.vec3([0, 0, 0]);
}
/**
* Gets the first control point on this CubicBezierCurve.
*
* Fires a {@link CubicBezierCurve#v1:event} event on change.
*
* Default value is ````[0.0, 0.0, 0.0]````
*
* @returns {Number[]} The first control point.
*/
get v1() {
return this._v1;
}
/**
* Sets the second control point on this CubicBezierCurve.
*
* Default value is ````[0.0, 0.0, 0.0]````
*
* @param {Number[]} value The second control point.
*/
set v2(value) {
this._v2 = value || math.vec3([0, 0, 0]);
}
/**
* Gets the second control point on this CubicBezierCurve.
*
* Default value is ````[0.0, 0.0, 0.0]````
*
* @returns {Number[]} The second control point.
*/
get v2() {
return this._v2;
}
/**
* Sets the end point on this CubicBezierCurve.
*
* Fires a {@link CubicBezierCurve#v3:event} event on change.
*
* Default value is ````[0.0, 0.0, 0.0]````
*
* @param {Number[]} value The end point.
*/
set v3(value) {
this.fire("v3", this._v3 = value || math.vec3([0, 0, 0]));
}
/**
* Gets the end point on this CubicBezierCurve.
*
* Fires a {@link CubicBezierCurve#v3:event} event on change.
*
* Default value is ````[0.0, 0.0, 0.0]````
*
* @returns {Number[]} The end point.
*/
get v3() {
return this._v3;
}
/**
* Sets the current position of progress along this CubicBezierCurve.
*
* Automatically clamps to range ````[0..1]````.
*
* @param {Number} value New progress time value.
*/
set t(value) {
value = value || 0;
this._t = value < 0.0 ? 0.0 : (value > 1.0 ? 1.0 : value);
}
/**
* Gets the current position of progress along this CubicBezierCurve.
*
* @returns {Number} Current progress time value.
*/
get t() {
return this._t;
}
/**
* Returns point on this CubicBezierCurve at the given position.
*
* @param {Number} t Position to get point at.
*
* @returns {Number[]} The point at the given position.
*/
get point() {
return this.getPoint(this._t);
}
/**
* Returns point on this CubicBezierCurve at the given position.
*
* @param {Number} t Position to get point at.
*
* @returns {Number[]} The point at the given position.
*/
getPoint(t) {
var vector = math.vec3();
vector[0] = math.b3(t, this._v0[0], this._v1[0], this._v2[0], this._v3[0]);
vector[1] = math.b3(t, this._v0[1], this._v1[1], this._v2[1], this._v3[1]);
vector[2] = math.b3(t, this._v0[2], this._v1[2], this._v2[2], this._v3[2]);
return vector;
}
getJSON() {
return {
v0: this._v0,
v1: this._v1,
v2: this._v2,
v3: this._v3,
t: this._t
};
}
}
export {CubicBezierCurve}