dom-region.js revision 7f301ced05415668ede239d3d16fe4a4199754e6
(function(Y) {
/**
* Adds position and region management functionality to DOM.
* @module dom
* @submodule dom-screen
* @for DOM
*/
var TOP = 'top',
RIGHT = 'right',
BOTTOM = 'bottom',
LEFT = 'left',
getOffsets = function(r1, r2) {
var t = Math.max(r1[TOP], r2[TOP]),
r = Math.min(r1[RIGHT], r2[RIGHT]),
b = Math.min(r1[BOTTOM], r2[BOTTOM]),
l = Math.max(r1[LEFT], r2[LEFT]),
ret = {};
ret[TOP] = t;
ret[RIGHT] = r;
ret[BOTTOM] = b;
ret[LEFT] = l;
return ret;
},
DOM = Y.DOM;
Y.mix(DOM, {
/**
* Returns an Object literal containing the following about this element: (top, right, bottom, left)
* @method region
* @param {HTMLElement} element The DOM element.
@return {Object} Object literal containing the following about this element: (top, right, bottom, left)
*/
region: function(node) {
var xy = DOM.getXY(node),
ret = false;
if (node && xy) {
ret = DOM._getRegion(
xy[1], // top
xy[0] + node.offsetWidth, // right
xy[1] + node.offsetHeight, // bottom
xy[0] // left
);
}
return ret;
},
/**
* Find the intersect information for the passes nodes.
* @method intersect
* @param {HTMLElement} element The first element
* @param {HTMLElement | Object} element2 The element or region to check the interect with
* @param {Object} altRegion An object literal containing the region for the first element if we already have the data (for performance i.e. DragDrop)
@return {Object} Object literal containing the following intersection data: (top, right, bottom, left, area, yoff, xoff, inRegion)
*/
intersect: function(node, node2, altRegion) {
var r = altRegion || DOM.region(node), region = {},
n = node2,
off;
if (n.tagName) {
region = DOM.region(n);
} else if (Y.Lang.isObject(node2)) {
region = node2;
} else {
return false;
}
off = getOffsets(region, r);
return {
top: off[TOP],
right: off[RIGHT],
bottom: off[BOTTOM],
left: off[LEFT],
area: ((off[BOTTOM] - off[TOP]) * (off[RIGHT] - off[LEFT])),
yoff: ((off[BOTTOM] - off[TOP])),
xoff: (off[RIGHT] - off[LEFT]),
inRegion: DOM.inRegion(node, node2, false, altRegion)
};
},
/**
* Check if any part of this node is in the passed region
* @method inRegion
* @param {Object} node2 The node to get the region from or an Object literal of the region
* $param {Boolean} all Should all of the node be inside the region
* @param {Object} altRegion An object literal containing the region for this node if we already have the data (for performance i.e. DragDrop)
* @return {Boolean} True if in region, false if not.
*/
inRegion: function(node, node2, all, altRegion) {
var region = {},
r = altRegion || DOM.region(node),
n = node2,
off;
if (n.tagName) {
region = DOM.region(n);
} else if (Y.Lang.isObject(node2)) {
region = node2;
} else {
return false;
}
if (all) {
return (
r[LEFT] >= region[LEFT] &&
r[RIGHT] <= region[RIGHT] &&
r[TOP] >= region[TOP] &&
r[BOTTOM] <= region[BOTTOM] );
} else {
off = getOffsets(region, r);
if (off[BOTTOM] >= off[TOP] && off[RIGHT] >= off[LEFT]) {
return true;
} else {
return false;
}
}
},
/**
* Check if any part of this element is in the viewport
* @method inViewportRegion
* @param {HTMLElement} element The DOM element.
* @param {Boolean} all Should all of the node be inside the region
* @param {Object} altRegion An object literal containing the region for this node if we already have the data (for performance i.e. DragDrop)
* @return {Boolean} True if in region, false if not.
*/
inViewportRegion: function(node, all, altRegion) {
return DOM.inRegion(node, DOM.viewportRegion(node), all, altRegion);
},
_getRegion: function(t, r, b, l) {
var region = {};
region[TOP] = region[1] = t;
region[LEFT] = region[0] = l;
region[BOTTOM] = b;
region[RIGHT] = r;
region.width = region[RIGHT] - region[LEFT];
region.height = region[BOTTOM] - region[TOP];
return region;
},
/**
* Returns an Object literal containing the following about the visible region of viewport: (top, right, bottom, left)
* @method viewportRegion
@return {Object} Object literal containing the following about the visible region of the viewport: (top, right, bottom, left)
*/
viewportRegion: function(node) {
node = node || Y.config.doc.documentElement;
var ret = false,
scrollX,
scrollY;
if (node) {
scrollX = DOM.docScrollX(node);
scrollY = DOM.docScrollY(node);
ret = DOM._getRegion(scrollY, // top
DOM.winWidth(node) + scrollX, // right
scrollY + DOM.winHeight(node), // bottom
scrollX); // left
}
return ret;
}
});
})(Y);