File: src/pixi/core/Polygon.js
/**
* @author Adrien Brault <adrien.brault@gmail.com>
*/
/**
* @class Polygon
* @constructor
* @param points {Array<Point>|Array<Number>} This cna be an array of Points or a flat array of numbers
* that will be interpreted as [x,y, x,y, ...]
*/
PIXI.Polygon = function(points)
{
//if this is a flat array of numbers, convert it to points
if(typeof points[0] === 'number') {
var p = [];
for(var i = 0, il = points.length; i < il; i+=2) {
p.push(
new PIXI.Point(points[i], points[i + 1])
);
}
points = p;
}
this.points = points;
}
/**
* @method clone
* @return a copy of the polygon
*/
PIXI.Polygon.prototype.clone = function()
{
var points = [];
for (var i=0; i<this.points.length; i++) {
points.push(this.points[i].clone());
}
return new PIXI.Polygon(points);
}
/**
* @method contains
* @param x {Number} The X coord of the point to test
* @param y {Number} The Y coord of the point to test
* @return if the x/y coords are within this polygon
*/
PIXI.Polygon.prototype.contains = function(x, y)
{
var inside = false;
// use some raycasting to test hits
// https://github.com/substack/point-in-polygon/blob/master/index.js
for(var i = 0, j = this.points.length - 1; i < this.points.length; j = i++) {
var xi = this.points[i].x, yi = this.points[i].y,
xj = this.points[j].x, yj = this.points[j].y,
intersect = ((yi > y) != (yj > y)) && (x < (xj - xi) * (y - yi) / (yj - yi) + xi);
if(intersect) inside = !inside;
}
return inside;
}
PIXI.Polygon.constructor = PIXI.Polygon;