1 YUI.add('anim-curve', function (Y, NAME) {

     2 

     3 /**

     4  * Adds support for the <code>curve</code> property for the <code>to</code>

     5  * attribute.  A curve is zero or more control points and an end point.

     6  * @module anim

     7  * @submodule anim-curve

     8  */

     9 

    10 Y.Anim.behaviors.curve = {

    11     set: function(anim, att, from, to, elapsed, duration, fn) {

    12         from = from.slice.call(from);

    13         to = to.slice.call(to);

    14         var t = fn(elapsed, 0, 100, duration) / 100;

    15         to.unshift(from);

    16         anim._node.setXY(Y.Anim.getBezier(to, t));

    17     },

    18 

    19     get: function(anim) {

    20         return anim._node.getXY();

    21     }

    22 };

    23 

    24 /**

    25  * Get the current position of the animated element based on t.

    26  * Each point is an array of "x" and "y" values (0 = x, 1 = y)

    27  * At least 2 points are required (start and end).

    28  * First point is start. Last point is end.

    29  * Additional control points are optional.

    30  * @for Anim

    31  * @method getBezier

    32  * @static

    33  * @param {Number[]} points An array containing Bezier points

    34  * @param {Number} t A number between 0 and 1 which is the basis for determining current position

    35  * @return {Number[]} An array containing int x and y member data

    36  */

    37 Y.Anim.getBezier = function(points, t) {

    38     var n = points.length,

    39         tmp = [],

    40         i,

    41         j;

    42 

    43     for (i = 0; i < n; ++i){

    44         tmp[i] = [points[i][0], points[i][1]]; // save input

    45     }

    46 

    47     for (j = 1; j < n; ++j) {

    48         for (i = 0; i < n - j; ++i) {

    49             tmp[i][0] = (1 - t) * tmp[i][0] + t * tmp[parseInt(i + 1, 10)][0];

    50             tmp[i][1] = (1 - t) * tmp[i][1] + t * tmp[parseInt(i + 1, 10)][1];

    51         }

    52     }

    53 

    54     return [ tmp[0][0], tmp[0][1] ];

    55 

    56 };

    57 

    58 

    59 }, '@VERSION@', {"requires": ["anim-xy"]});