Merge pull request phaserjs#3307 from RiCoTeRoX/curves-quadratic

Add quadraticBezier to API

Author: photonstorm

src/curves/QuadraticBezier.js

@@ -0,0 +1,191 @@
+/**
+ * @author       Richard Davey <rich@photonstorm.com>
+ * @copyright    2018 Photon Storm Ltd.
+ * @license      {@link https://github.com/photonstorm/phaser/blob/master/license.txt|MIT License}
+ */
+
+
+var Class = require('../utils/Class');
+var QuadraticBezierInter = require('../math/interpolation/QuadraticBezierInterpolation');
+var Curve = require('./Curve');
+var Vector2 = require('../math/Vector2');
+
+/**
+ * @classdesc
+ * [description]
+ *
+ * @class QuadraticBezier
+ * @extends Phaser.Curves.Curve
+ * @memberOf Phaser.Curves
+ * @constructor
+ * @since 3.0.0
+ *
+ * @param {Phaser.Math.Vector2|Phaser.Math.Vector2[]} p0 - Start point, or an array of point pairs.
+ * @param {Phaser.Math.Vector2} p1 - Control Point 1.
+ * @param {Phaser.Math.Vector2} p2 - Control Point 2.
+ * @param {Phaser.Math.Vector2} p3 - End Point.
+ */
+var QuadraticBezier = new Class({
+
+    Extends: Curve,
+
+    initialize:
+
+    function QuadraticBezier (p0, p1, p2)
+    {
+        Curve.call(this, 'QuadraticBezier');
+
+        if (Array.isArray(p0))
+        {
+            p2 = new Vector2(p0[4], p0[5]);
+            p1 = new Vector2(p0[2], p0[3]);
+            p0 = new Vector2(p0[0], p0[1]);
+        }
+
+        /**
+         * [description]
+         *
+         * @name Phaser.Curves.QuadraticBezier#p0
+         * @type {Phaser.Math.Vector2}
+         * @since 3.0.0
+         */
+        this.p0 = p0;
+
+        /**
+         * [description]
+         *
+         * @name Phaser.Curves.QuadraticBezier#p1
+         * @type {Phaser.Math.Vector2}
+         * @since 3.0.0
+         */
+        this.p1 = p1;
+
+        /**
+         * [description]
+         *
+         * @name Phaser.Curves.QuadraticBezier#p2
+         * @type {Phaser.Math.Vector2}
+         * @since 3.0.0
+         */
+        this.p2 = p2;
+    },
+
+    /**
+     * [description]
+     *
+     * @method Phaser.Curves.QuadraticBezier#getStartPoint
+     * @since 3.0.0
+     *
+     * @param {Phaser.Math.Vector2} out - [description]
+     *
+     * @return {Phaser.Math.Vector2} [description]
+     */
+    getStartPoint: function (out)
+    {
+        if (out === undefined) { out = new Vector2(); }
+
+        return out.copy(this.p0);
+    },
+
+    /**
+     * [description]
+     *
+     * @method Phaser.Curves.QuadraticBezier#getResolution
+     * @since 3.0.0
+     *
+     * @param {[type]} divisions - [description]
+     *
+     * @return {[type]} [description]
+     */
+    getResolution: function (divisions)
+    {
+        return divisions;
+    },
+
+    /**
+     * [description]
+     *
+     * @method Phaser.Curves.QuadraticBezier#getPoint
+     * @since 3.0.0
+     *
+     * @param {[type]} t - [description]
+     * @param {[type]} out - [description]
+     *
+     * @return {[type]} [description]
+     */
+    getPoint: function (t, out)
+    {
+        if (out === undefined) { out = new Vector2(); }
+
+        var p0 = this.p0;
+        var p1 = this.p1;
+        var p2 = this.p2;
+
+        return out.set(QuadraticBezierInter(t, p0.x, p1.x, p2.x), QuadraticBezierInter(t, p0.y, p1.y, p2.y));
+    },
+
+    /**
+     * [description]
+     *
+     * @method Phaser.Curves.QuadraticBezier#draw
+     * @since 3.0.0
+     *
+     * @param {Phaser.GameObjects.Graphics} graphics - [description]
+     * @param {integer} [pointsTotal=32] - [description]
+     *
+     * @return {Phaser.GameObjects.Graphics} [description]
+     */
+    draw: function (graphics, pointsTotal)
+    {
+        if (pointsTotal === undefined) { pointsTotal = 32; }
+
+        var points = this.getPoints(pointsTotal);
+
+        graphics.beginPath();
+        graphics.moveTo(this.p0.x, this.p0.y);
+
+        for (var i = 1; i < points.length; i++)
+        {
+            graphics.lineTo(points[i].x, points[i].y);
+        }
+
+        graphics.strokePath();
+
+        //  So you can chain graphics calls
+        return graphics;
+    },
+
+    /**
+     * [description]
+     *
+     * @method Phaser.Curves.QuadraticBezier#toJSON
+     * @since 3.0.0
+     *
+     * @return {object} [description]
+     */
+    toJSON: function ()
+    {
+        return {
+            type: this.type,
+            points: [
+                this.p0.x, this.p0.y,
+                this.p1.x, this.p1.y,
+                this.p2.x, this.p2.y
+            ]
+        };
+    }
+
+});
+
+QuadraticBezier.fromJSON = function (data)
+{
+    var points = data.points;
+
+    var p0 = new Vector2(points[0], points[1]);
+    var p1 = new Vector2(points[2], points[3]);
+    var p2 = new Vector2(points[4], points[5]);
+
+    return new QuadraticBezier(p0, p1, p2);
+};
+
+module.exports = QuadraticBezier;

src/curves/index.js

@@ -9,13 +9,12 @@
  */
 
 module.exports = {
-
     Path: require('./path/Path'),
 
     CubicBezier: require('./CubicBezierCurve'),
     Curve: require('./Curve'),
     Ellipse: require('./EllipseCurve'),
     Line: require('./LineCurve'),
-    Spline: require('./SplineCurve')
-
+    Spline: require('./SplineCurve'),
+    QuadraticBezier: require('./QuadraticBezier')
 };

src/math/interpolation/QuadraticBezierInterpolation.js

@@ -0,0 +1,48 @@
+/**
+ * @author       Richard Davey <rich@photonstorm.com>
+ * @copyright    2018 Photon Storm Ltd.
+ * @license      {@link https://github.com/photonstorm/phaser/blob/master/license.txt|MIT License}
+ */
+
+function P0 (t, p)
+{
+    var k = 1 - t;
+
+    return k * k * p;
+}
+
+function P1 (t, p)
+{
+    return 2 * ( 1 - t ) * t * p;
+}
+
+function P2 (t, p)
+{
+    return t * t * p;
+}
+
+//  p0 = start point
+//  p1 = control point 1
+//  p2 = end point
+
+// https://github.com/mrdoob/three.js/blob/master/src/extras/core/Interpolations.js
+
+/**
+ * [description]
+ *
+ * @function Phaser.Math.Interpolation.QuadraticBezier
+ * @since 3.0.0
+ *
+ * @param {float} t - [description]
+ * @param {number} p0 - [description]
+ * @param {number} p1 - [description]
+ * @param {number} p2 - [description]
+ *
+ * @return {number} [description]
+ */
+var QuadraticBezierInterpolation = function (t, p0, p1, p2)
+{
+    return P0(t, p0) + P1(t, p1) + P2(t, p2);
+};
+
+module.exports = QuadraticBezierInterpolation;

src/math/interpolation/index.js

@@ -9,10 +9,9 @@
  */
 
 module.exports = {
-
     Bezier: require('./BezierInterpolation'),
     CatmullRom: require('./CatmullRomInterpolation'),
     CubicBezier: require('./CubicBezierInterpolation'),
-    Linear: require('./LinearInterpolation')
-
+    Linear: require('./LinearInterpolation'),
+    QuadraticBezier: require('./QuadraticBezierInterpolation')
 };