/**
* A region is a representation of an object on a grid. It is defined
* by the top, right, bottom, left extents, so is rectangular by default. If
* other shapes are required, this class could be extended to support it.
* @namespace YAHOO.util
* @class Region
* @param {Int} t the top extent
* @param {Int} r the right extent
* @param {Int} b the bottom extent
* @param {Int} l the left extent
* @constructor
*/
YAHOO.util.Region = function(t, r, b, l) {
/**
* The region's top extent
* @property top
* @type Int
*/
this.top = t;
/**
* The region's top extent as index, for symmetry with set/getXY
* @property 1
* @type Int
*/
this[1] = t;
/**
* The region's right extent
* @property right
* @type int
*/
this.right = r;
/**
* The region's bottom extent
* @property bottom
* @type Int
*/
this.bottom = b;
/**
* The region's left extent
* @property left
* @type Int
*/
this.left = l;
/**
* The region's left extent as index, for symmetry with set/getXY
* @property 0
* @type Int
*/
this[0] = l;
};
/**
* Returns true if this region contains the region passed in
* @method contains
* @param {Region} region The region to evaluate
* @return {Boolean} True if the region is contained with this region,
* else false
*/
YAHOO.util.Region.prototype.contains = function(region) {
return ( region.left >= this.left &&
region.right <= this.right &&
region.top >= this.top &&
region.bottom <= this.bottom );
// this.logger.debug("does " + this + " contain " + region + " ... " + ret);
};
/**
* Returns the area of the region
* @method getArea
* @return {Int} the region's area
*/
YAHOO.util.Region.prototype.getArea = function() {
return ( (this.bottom - this.top) * (this.right - this.left) );
};
/**
* Returns the region where the passed in region overlaps with this one
* @method intersect
* @param {Region} region The region that intersects
* @return {Region} The overlap region, or null if there is no overlap
*/
YAHOO.util.Region.prototype.intersect = function(region) {
var t = Math.max( this.top, region.top );
var r = Math.min( this.right, region.right );
var b = Math.min( this.bottom, region.bottom );
var l = Math.max( this.left, region.left );
if (b >= t && r >= l) {
return new YAHOO.util.Region(t, r, b, l);
} else {
return null;
}
};
/**
* Returns the region representing the smallest region that can contain both
* the passed in region and this region.
* @method union
* @param {Region} region The region that to create the union with
* @return {Region} The union region
*/
YAHOO.util.Region.prototype.union = function(region) {
var t = Math.min( this.top, region.top );
var r = Math.max( this.right, region.right );
var b = Math.max( this.bottom, region.bottom );
var l = Math.min( this.left, region.left );
return new YAHOO.util.Region(t, r, b, l);
};
/**
* toString
* @method toString
* @return string the region properties
*/
YAHOO.util.Region.prototype.toString = function() {
return ( "Region {" +
"top: " + this.top +
", right: " + this.right +
", bottom: " + this.bottom +
", left: " + this.left +
"}" );
};
/**
* Returns a region that is occupied by the DOM element
* @method getRegion
* @param {HTMLElement} el The element
* @return {Region} The region that the element occupies
* @static
*/
YAHOO.util.Region.getRegion = function(el) {
var p = YAHOO.util.Dom.getXY(el);
var t = p[1];
var r = p[0] + el.offsetWidth;
var b = p[1] + el.offsetHeight;
var l = p[0];
return new YAHOO.util.Region(t, r, b, l);
};
/////////////////////////////////////////////////////////////////////////////
/**
* A point is a region that is special in that it represents a single point on
* the grid.
* @namespace YAHOO.util
* @class Point
* @param {Int} x The X position of the point
* @param {Int} y The Y position of the point
* @constructor
* @extends YAHOO.util.Region
*/
YAHOO.util.Point = function(x, y) {
if (x instanceof Array) { // accept output from Dom.getXY
y = x[1];
x = x[0];
}
/**
* The X position of the point, which is also the right, left and index zero (for Dom.getXY symmetry)
* @property x
* @type Int
*/
this.x = this.right = this.left = this[0] = x;
/**
* The Y position of the point, which is also the top, bottom and index one (for Dom.getXY symmetry)
* @property y
* @type Int
*/
this.y = this.top = this.bottom = this[1] = y;
};
YAHOO.util.Point.prototype = new YAHOO.util.Region();