grobe Integration vom Raumplaner.

2 files changed, 1220 insertions, 0 deletions

diff --git a/modules-available/roomplanner/js/lib/jquery-collision.js b/modules-available/roomplanner/js/lib/jquery-collision.js
new file mode 100644
index 00000000..98e37882
--- /dev/null
+++ b/modules-available/roomplanner/js/lib/jquery-collision.js
@@ -0,0 +1,394 @@
+/*
+Copyright (c) 2011 Sean Cusack
+
+MIT-LICENSE:
+
+Permission is hereby granted, free of charge, to any person obtaining
+a copy of this software and associated documentation files (the
+"Software"), to deal in the Software without restriction, including
+without limitation the rights to use, copy, modify, merge, publish,
+distribute, sublicense, and/or sell copies of the Software, and to
+permit persons to whom the Software is furnished to do so, subject to
+the following conditions:
+
+The above copyright notice and this permission notice shall be
+included in all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+*/
+
+(function($){
+
+	//
+	// Private classes
+	//
+
+	function CollisionCoords( proto, containment )
+	{
+		if( ! proto )
+		{
+			// default if nothing else:
+			this.x1 = this.y1 = this.x2 = this.y2 = 0;
+			this.proto = null;
+		}
+		else if( "offset" in proto )
+		{
+			// used to grab stuff from a jquery object
+			// if it has collision-coordinates data, use that
+			// otherwise just pull in the offset
+
+			var d = proto.data("jquery-collision-coordinates");
+			if( d )
+			{
+				this.x1 = d.x1;
+				this.y1 = d.y1;
+				this.x2 = d.x2;
+				this.y2 = d.y2;
+			}
+			else if( containment && containment.length && containment.length >= 4 )
+			{
+				this.x1 = containment[0];
+				this.y1 = containment[1];
+				this.x2 = containment[2]+proto.outerWidth(true);
+				this.y2 = containment[3]+proto.outerHeight(true);
+			}
+			else if( proto.parent().length <= 0 )
+			{
+				this.x1 = parseInt(proto.css("left"  )) || 0;
+				this.y1 = parseInt(proto.css("top"   )) || 0;
+				this.x2 = parseInt(proto.css("width" )) || 0;
+				this.y2 = parseInt(proto.css("height")) || 0;
+				this.x2 += this.x1;
+				this.x2 += (parseInt(proto.css("margin-left"))||0) + (parseInt(proto.css("border-left"))||0) + (parseInt(proto.css("padding-left"))||0) + 
+									 (parseInt(proto.css("padding-right"))||0) + (parseInt(proto.css("border-right"))||0) + (parseInt(proto.css("margin-right"))||0);
+				this.y2 += this.y1;
+				this.y2 += (parseInt(proto.css("margin-top"))||0) + (parseInt(proto.css("border-top"))||0) + (parseInt(proto.css("padding-top"))||0) + 
+									 (parseInt(proto.css("padding-bottom"))||0) + (parseInt(proto.css("border-bottom"))||0) + (parseInt(proto.css("margin-bottom"))||0);
+			}
+			else
+			{
+				var o = proto.offset();
+				this.x1 = o.left - (parseInt(proto.css("margin-left"))||0); // not also border -- offset starts from inside margin but outside border
+				this.y1 = o.top  - (parseInt(proto.css("margin-top" ))||0); // not also border -- offset starts from inside margin but outside border
+				this.x2 = this.x1 + proto.outerWidth(true);
+				this.y2 = this.y1 + proto.outerHeight(true);
+			}
+			this.proto = proto;
+		}
+		else if( "x1" in proto )
+		{
+			// used to effectively "clone"
+			this.x1 = proto.x1;
+			this.y1 = proto.y1;
+			this.x2 = proto.x2;
+			this.y2 = proto.y2;
+			this.proto = proto;
+		}
+
+		if( "dir" in proto )
+		{
+			this.dir = proto.dir;
+		}
+	}
+	
+	CollisionCoords.prototype.innerContainer = function()
+	{
+		var clone = new CollisionCoords( this );
+		if( this.proto["css"] )
+		{
+			clone.x1 += parseInt( this.proto.css( "margin-left"  ) ) || 0;
+			clone.x1 += parseInt( this.proto.css( "border-left"  ) ) || 0;
+			clone.x1 += parseInt( this.proto.css("padding-left"  ) ) || 0;
+			clone.x2 -= parseInt( this.proto.css("padding-right" ) ) || 0;
+			clone.x2 -= parseInt( this.proto.css( "border-right" ) ) || 0;
+			clone.x2 -= parseInt( this.proto.css( "margin-right" ) ) || 0;
+			clone.y1 += parseInt( this.proto.css( "margin-top"   ) ) || 0;
+			clone.y1 += parseInt( this.proto.css( "border-top"   ) ) || 0;
+			clone.y1 += parseInt( this.proto.css("padding-top"   ) ) || 0;
+			clone.y2 -= parseInt( this.proto.css("padding-bottom") ) || 0;
+			clone.y2 -= parseInt( this.proto.css( "border-bottom") ) || 0;
+			clone.y2 -= parseInt( this.proto.css( "margin-bottom") ) || 0;
+		}
+		return clone;
+	}
+
+	CollisionCoords.prototype.move = function( dx, dy )
+	{
+		this.x1 += dx;
+		this.x2 += dx;
+		this.y1 += dy;
+		this.y2 += dy;
+		return this;
+	};
+	
+	CollisionCoords.prototype.update = function( obj )
+	{
+		if( "x1" in obj ) this.x1 = obj["x1"];
+		if( "x2" in obj ) this.x1 = obj["x2"];
+		if( "y1" in obj ) this.x1 = obj["y1"];
+		if( "y2" in obj ) this.x1 = obj["y2"];
+		if( "left" in obj )
+		{
+			var w = this.x2-this.x1;
+			this.x1 = obj["left"];
+			this.x2 = this.x1 + w;
+		}
+		if( "top" in obj )
+		{
+			var h = this.y2-this.y1;
+			this.y1 = obj["top"];
+			this.y2 = this.y1 + h;
+		}
+		if( "offset" in obj )
+		{
+			var o = obj.offset();
+			this.update( o );
+			this.x2 = this.x1 + obj.width();
+			this.y2 = this.y1 + obj.height();
+		}
+		if( "dir" in obj ) this.x1 = obj["dir"];
+		return this;
+	};
+	
+	CollisionCoords.prototype.width   = function() { return ( this.x2 - this.x1 );     };
+	CollisionCoords.prototype.height  = function() { return ( this.y2 - this.y1 );     };
+	CollisionCoords.prototype.centerx = function() { return ( this.x1 + this.x2 ) / 2; };
+	CollisionCoords.prototype.centery = function() { return ( this.y1 + this.y2 ) / 2; };
+
+	
+	CollisionCoords.prototype.toString = function()
+	{
+		return ( this.proto["get"] ? "#"+this.proto.get(0).id : "" ) + "["+[this.x1,this.y1,this.x2,this.y2].join(",")+"]";
+	};
+	
+	// the big mistake in a lot of collision-detectors,
+	// make floating-point arithmetic work for you, not against you:
+	CollisionCoords.EPSILON = 0.001;
+	
+	CollisionCoords.prototype.containsPoint = function( x, y, inclusive )
+	{
+		if( ! inclusive ) inclusive = false;
+		var epsilon = ( inclusive ? -1 : +1 ) * CollisionCoords.EPSILON;
+		if( ( x > ( this.x1 + epsilon ) && x < ( this.x2 - epsilon ) ) &&
+				( y > ( this.y1 + epsilon ) && y < ( this.y2 - epsilon ) )    )
+			return true;
+		else
+			return false;
+	};
+	
+	CollisionCoords.prototype.overlaps = function( other, inclusive )
+	{
+		var hit = this._overlaps( other, inclusive );
+		if( hit.length > 0 ) return hit;
+				hit = other._overlaps( this, inclusive );
+		if( hit.length > 0 )
+		{
+			hit[0].dir = hit[0].dir == "Inside"  ? "Outside" :
+									 hit[0].dir == "Outside" ? "Inside"  :
+									 hit[0].dir == "N"       ? "S"       :
+									 hit[0].dir == "S"       ? "N"       :
+									 hit[0].dir == "W"       ? "E"       :
+									 hit[0].dir == "E"       ? "W"       :
+									 hit[0].dir == "NE"      ? "SW"      :
+									 hit[0].dir == "SW"      ? "NE"      :
+									 hit[0].dir == "SE"      ? "NW"      :
+									 hit[0].dir == "NW"      ? "SE"      :
+																						 undefined;
+		}
+		return hit || [];
+	}
+
+	CollisionCoords.prototype._overlaps = function( other, inclusive )
+	{
+		var c1 = other;
+		var c2 = this;
+		if( ! inclusive ) inclusive = false;
+		var ax = c1.centerx();
+		var ay = c1.centery();
+		// nine points to check whether they're in e2: e1's four corners, e1's center-sides, and e1's center
+		// if center of e1 is within e2, there's some kind of total inclusion
+		var points = [ [c1.x1,c1.y1,"SE"], [c1.x2,c1.y1,"SW"], [c1.x2,c1.y2,"NW"], [c1.x1,c1.y2,"NE"], [ax,c1.y1,"S"], [c1.x2,ay,"W"], [ax,c1.y2,"N"], [c1.x1,ay,"E"], [ax,ay,undefined] ];
+		var hit    = null;
+		var dirs   = { NW:false, N:false, NE:false, E:false, SE:false, S:false, SW:false, W:false };
+		for( var i=0; i<points.length; i++ )
+		{
+			if( this.containsPoint( points[i][0], points[i][1], inclusive ) )
+			{
+				if( points[i][2] ) dirs[points[i][2]] = true;
+				if( hit ) continue; // don't need to make another one - it'll be the same anyways //
+				hit = [ new CollisionCoords( { x1: Math.max(c1.x1,c2.x1), y1: Math.max(c1.y1,c2.y1),
+																			 x2: Math.min(c1.x2,c2.x2), y2: Math.min(c1.y2,c2.y2), dir: points[i][2]  } ) ];
+			}
+		}
+		if( hit )
+		{
+			if( dirs["NW"] && dirs["NE"] ) hit[0].dir = "N";
+			if( dirs["NE"] && dirs["SE"] ) hit[0].dir = "E";
+			if( dirs["SE"] && dirs["SW"] ) hit[0].dir = "S";
+			if( dirs["SW"] && dirs["NW"] ) hit[0].dir = "W";
+			if( dirs["NW"] && dirs["NE"] &&
+					dirs["SE"] && dirs["SW"] ) hit[0].dir = "Outside";
+			if( !dirs["NW"] && !dirs["NE"] &&
+					!dirs["SE"] && !dirs["SW"] &&
+					!dirs["N"] && !dirs["E"] &&
+					!dirs["S"] && !dirs["W"] ) hit[0].dir = "Inside";
+		}
+		return hit || [];
+	};
+	
+	CollisionCoords.prototype._protrusion = function( area, dir, list )
+	{
+		var o = this.overlaps( new CollisionCoords( area ), false );
+		if( o.length <= 0 ) return list;
+		o[0].dir = dir;
+		list.push( o[0] );
+		return list;
+	};
+
+	CollisionCoords.prototype.protrusions = function( container )
+	{
+		var list = [];
+		var n    = Number.NEGATIVE_INFINITY;
+		var p    = Number.POSITIVE_INFINITY;
+		var l    = container.x1;
+		var r    = container.x2;
+		var t    = container.y1;
+		var b    = container.y2;
+		list = this._protrusion( { x1:l, y1:n, x2:r, y2:t }, "N" , list );
+		list = this._protrusion( { x1:r, y1:n, x2:p, y2:t }, "NE", list );
+		list = this._protrusion( { x1:r, y1:t, x2:p, y2:b }, "E" , list );
+		list = this._protrusion( { x1:r, y1:b, x2:p, y2:p }, "SE", list );
+		list = this._protrusion( { x1:l, y1:b, x2:r, y2:p }, "S" , list );
+		list = this._protrusion( { x1:n, y1:b, x2:l, y2:p }, "SW", list );
+		list = this._protrusion( { x1:n, y1:t, x2:l, y2:b }, "W" , list );
+		list = this._protrusion( { x1:n, y1:n, x2:l, y2:t }, "NW", list );
+		return list;
+	};
+	
+	function Collision( targetNode, obstacleNode, overlapCoords, overlapType )
+	{
+		this.target        = targetNode;
+		this.obstacle      = obstacleNode;
+		this.overlap       = overlapCoords;
+		this.overlapType   = overlapType;
+	}
+	
+	Collision.prototype.distance = function( other )
+	{
+		var tc = c.target;
+		var oc = c.overlap;
+		return Math.sqrt( (tc.centerx()-oc.centerx())*(tc.centerx()-oc.centerx()) +
+											(tc.centery()-oc.centery())*(tc.centery()-oc.centery())   );
+	}
+
+	function CollisionFactory( targets, obstacles, containment )
+	{
+		this.targets   = targets;
+		this.obstacles = obstacles;
+		this.collisions = null;
+		this.cache      = null;
+		if( containment ) this.containment = containment;
+		else              this.containment = null;
+	}
+	
+	CollisionFactory.prototype.getCollisions = function( overlapType )
+	{
+		if( this.collisions !== null ) return this.collisions;
+		this.cache = {};
+		this.collisions = [];
+		// note: doesn't do any dup-detection, so if you ask if something collides with
+		// itself, it will!
+		if( ! overlapType ) overlapType = "collision";
+		if( overlapType != "collision" && overlapType != "protrusion" ) return [];
+		var c = [];
+		var t = this.targets;  
+		var o = this.obstacles;
+		for( var ti=0; ti<t.length; ti++ )
+		{
+			var tc = t[ti];
+			for( var oi=0; oi<o.length; oi++ )
+			{
+				var oc = o[oi];
+				var ol = ( (overlapType=="collision") ? tc.overlaps( oc ) : tc.protrusions( oc.innerContainer() ) );
+				for( var oli=0; oli<ol.length; oli++ )
+				{
+					c.push( new Collision( t[ti], o[oi], ol[oli], overlapType ) );
+				}
+			}
+		}
+		this.collisions = c;
+		return c;
+	};
+
+	//
+	// Setup
+	//
+	
+	function makeCoordsArray( j )
+	{
+		return $(j).get().map(function(e,i,a){ return new CollisionCoords( $(e) ); });
+	}
+
+	function combineQueries( array )
+	{
+		var j = $();
+		for( var i=0; i<array.length; i++ )
+		{
+			j=j.add( array[i] );
+		}
+		return j;
+	}
+
+	$.fn.collision = function( selector, options )
+	{
+		if( ! options ) options = {};
+		var mode = "collision";
+		var as   = null;
+		var cd   = null;
+		var od   = null;
+		var dd   = null;
+		var rel  = "body"; // can be "body" (default), "collider", "obstacle", or a selector
+		if( options.mode == "protrusion" ) mode = options.mode;
+		if( options.as                   ) as   = options.as;
+		if( options.colliderData         ) cd   = options.colliderData;
+		if( options.obstacleData         ) od   = options.obstacleData;
+		if( options.directionData        ) dd   = options.directionData;
+		if( options.relative             ) rel  = options.relative;
+		var cf = new CollisionFactory( makeCoordsArray(this), makeCoordsArray(selector) );
+		var ov = cf.getCollisions( mode );
+		var array;
+		// if no "as", then just the jquery object that we collided with
+		// but if there's as="<div/>", then make div's out of the overlaps
+		if( ! as ) array = $.map( ov, function(e,i,a){ return e.obstacle.proto; } );
+		else       array = $.map( ov, function(e,i,a){ var xoff = e.overlap.x1;
+																								var yoff = e.overlap.y1;
+																								if( rel && rel != "body" ) 
+																								{ 
+																									var r = rel == "collider" ? $(e.target.proto) :
+																													rel == "obstacle" ? $(e.obstacle.proto) :
+																																							$(rel);
+																									if( r.length>0 ) 
+																									{ 
+																										var roff = r.offset();
+																										xoff -= roff.left;
+																										yoff -= roff.top;
+																									}
+																								}
+																								var c = $(as).offset( { left: xoff, top: yoff } )
+																														 .width(  e.overlap.width() )
+																														 .height( e.overlap.height() );
+																								if( cd ) c.data(cd, $(e.target.proto));
+																								if( od ) c.data(od, $(e.obstacle.proto));
+																								if( dd && e.overlap.dir ) c.data(dd, e.overlap.dir);
+																								return c;
+																							} );
+		return combineQueries( array );
+	};
+
+})(jQuery);
diff --git a/modules-available/roomplanner/js/lib/jquery-ui-draggable-collision.js b/modules-available/roomplanner/js/lib/jquery-ui-draggable-collision.js
new file mode 100644
index 00000000..3ef553b1
--- /dev/null
+++ b/modules-available/roomplanner/js/lib/jquery-ui-draggable-collision.js
@@ -0,0 +1,826 @@
+/*
+Copyright (c) 2014 Djuri Baars
+Copyright (c) 2011 Sean Cusack
+
+MIT-LICENSE:
+
+Permission is hereby granted, free of charge, to any person obtaining
+a copy of this software and associated documentation files (the
+"Software"), to deal in the Software without restriction, including
+without limitation the rights to use, copy, modify, merge, publish,
+distribute, sublicense, and/or sell copies of the Software, and to
+permit persons to whom the Software is furnished to do so, subject to
+the following conditions:
+
+The above copyright notice and this permission notice shall be
+included in all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+*/
+
+(function($){
+	// Default settings
+	var DEBUG = false;
+	var VISUAL_DEBUG = DEBUG;
+
+	$.ui.draggable.prototype.options.obstacle          = ".ui-draggable-collision-obstacle";
+	$.ui.draggable.prototype.options.restraint         = ".ui-draggable-collision-restraint";
+	$.ui.draggable.prototype.options.collider          = ".ui-draggable-dragging";
+	$.ui.draggable.prototype.options.colliderData      = null;
+	$.ui.draggable.prototype.options.obstacleData      = null;
+	$.ui.draggable.prototype.options.directionData     = null;
+	$.ui.draggable.prototype.options.relative          = "body";
+	$.ui.draggable.prototype.options.preventCollision  = false;
+	$.ui.draggable.prototype.options.preventProtrusion = false;
+	$.ui.draggable.prototype.options.collisionVisualDebug = false;
+	$.ui.draggable.prototype.options.multipleCollisionInteractions = [];
+
+	// Plugin setup
+	$.ui.plugin.add( "draggable", "obstacle", {
+		create: function(event,ui){       handleInit   .call( this, event, ui ); },
+		start: function(event,ui){        handleStart  .call( this, event, ui ); } ,
+		drag:  function(event,ui){ return handleCollide.call( this, event, ui ); } ,
+		stop:  function(event,ui){        handleCollide.call( this, event, ui );
+																			handleStop   .call( this, event, ui ); }
+	});
+
+	// NOTE: the "handleCollide" function must do all collision and protrusion detection at once, in order for the
+	//       simultaneous prevention cases to work properly, so basically, if you ask for both, the obstacle events
+	//       will occur first (and do both), and then these will trigger, see that they have an obstacle, and not
+	//       do anything a second time
+	$.ui.plugin.add( "draggable", "restraint", {
+		create: function(event,ui){         handleInit   .call( this, event, ui ); },
+		start: function(event,ui){ if( ! $(this).data("ui-draggable").options.obstacle ) // if there are obstacles, we already handled both
+															 {
+																				handleStart  .call( this, event, ui );
+															 }
+														 } ,
+		drag:  function(event,ui){ if( ! $(this).data("ui-draggable").options.obstacle ) // if there are obstacles, we already handled both
+															 {
+																 return handleCollide.call( this, event, ui );
+															 }
+														 } ,
+		stop:  function(event,ui){ if( ! $(this).data("ui-draggable").options.obstacle ) // if there are obstacles, we already handled both
+															 {
+																				handleCollide.call( this, event, ui );
+																				handleStop   .call( this, event, ui );
+															 }
+														 }
+	});
+
+	// Likewise, if we already have an obstacle or restraint, we've done it all, so don't repeat
+	$.ui.plugin.add( "draggable", "multipleCollisionInteractions", {
+		create: function(event,ui){         handleInit   .call( this, event, ui ); },
+		start: function(event,ui){ if( ! $(this).data("ui-draggable").options.obstacle &&
+																	 ! $(this).data("ui-draggable").options.restraint   )
+															 {
+																				handleStart  .call( this, event, ui );
+															 }
+														 } ,
+		drag:  function(event,ui){ if( ! $(this).data("ui-draggable").options.obstacle &&
+																	 ! $(this).data("ui-draggable").options.restraint   )
+															 {
+																 return handleCollide.call( this, event, ui );
+															 }
+														 } ,
+		stop:  function(event,ui){ if( ! $(this).data("ui-draggable").options.obstacle &&
+																	 ! $(this).data("ui-draggable").options.restraint   )
+															 {
+																				handleCollide.call( this, event, ui );
+																				handleStop   .call( this, event, ui );
+															 }
+														 }
+	});
+
+
+	//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
+	//
+	// Private Classes
+	//
+
+	////////////
+	// EVENTS //
+	////////////
+
+	function CollisionEvent( eventType, collider, obstacle, collisionType, collision )
+	{
+		jQuery.Event.call( this, eventType );
+		this.collider  = collider;
+		this.obstacle  = obstacle;
+		this.collisionType = collisionType;
+		this.collision = collision;
+	}
+
+	CollisionEvent.prototype = new $.Event( "" );
+
+	function CollisionCheckEvent( eventType, collider, obstacle, collisionType )
+	{
+		jQuery.Event.call( this, eventType );
+		this.collider  = collider;
+		this.obstacle  = obstacle;
+		this.collisionType = collisionType;
+	}
+
+	CollisionCheckEvent.prototype = new $.Event( "" );
+
+	//////////////////////
+	// COORDINATE CLASS //
+	//////////////////////
+
+	function Coords( x1, y1, x2, y2 )
+	{
+		this.x1 = x1;
+		this.y1 = y1;
+		this.x2 = x2;
+		this.y2 = y2;
+	}
+
+	Coords.prototype.width   = function() { return (this.x2-this.x1);   };
+	Coords.prototype.height  = function() { return (this.y2+this.y1);   };
+	Coords.prototype.centerx = function() { return (this.x1+this.x2)/2; };
+	Coords.prototype.centery = function() { return (this.y1+this.y2)/2; };
+	Coords.prototype.area    = function() { return this.width()*this.height(); };
+	Coords.prototype.hash    = function() { return "["+[this.x1,this.y1,this.x2,this.y2].join(",")+"]"; };
+	Coords.prototype.distance = function(c)
+	{
+		return this.distanceTo( c.centerx(), c.centery() );
+	};
+
+	Coords.prototype.distanceTo = function(x,y)
+	{
+		var dx = this.centerx()-x;
+		var dy = this.centerx()-y;
+		return Math.sqrt( dx*dx + dy*dy );
+	};
+
+	/////////////////////////////////
+	// COORDINATE HELPER FUNCTIONS //
+	/////////////////////////////////
+
+	// create a box with the same total area, centered at center of gravity
+	function centerGravity( coordsList )
+	{
+		if( coordsList.length <= 0 ) return null;
+		var wsumx = 0;
+		var wsumy = 0;
+		var suma  = 0;
+		for( var i = 0; i < coordsList.length; i++ )
+		{
+			suma += coordsList[i].area();
+			wsumx += coordsList[i].centerx() * coordsList[i].area();
+			wsumy += coordsList[i].centery() * coordsList[i].area();
+		}
+		var d = Math.sqrt( suma ); // dimension of square (both w and h)
+		return new Coords( (wsumx/suma) - d/2, (wsumy/suma) - d/2, (wsumx/suma) + d/2, (wsumy/suma) + d/2 );
+	}
+
+	// convert a jq object into a Coords object, handling all the nice-n-messy offsets and margins and crud
+	function jq2Coords( jq, dx, dy )
+	{
+		var x1,y1, x2, y2;
+
+		if( !dx ) dx=0;
+		if( !dy ) dy=0;
+		if( jq.parent().length > 0 )
+		{
+			x1 = dx + jq.offset().left - (parseInt(jq.css("margin-left"))||0);
+			y1 = dy + jq.offset().top  - (parseInt(jq.css("margin-top" ))||0);
+			x2 = x1 + jq.outerWidth( true);
+			y2 = y1 + jq.outerHeight(true);
+		} else {
+			x1 = dx + parseInt(jq.css("left"  )) || 0;
+			y1 = dy + parseInt(jq.css("top"   )) || 0;
+			x2 = x1 + parseInt(jq.css("width" )) || 0;
+			y2 = y1 + parseInt(jq.css("height")) || 0;
+			x2 += (parseInt(jq.css("margin-left"))||0) + (parseInt(jq.css("border-left"))||0) + (parseInt(jq.css("padding-left"))||0) +
+						(parseInt(jq.css("padding-right"))||0) + (parseInt(jq.css("border-right"))||0) + (parseInt(jq.css("margin-right"))||0);
+			y2 += (parseInt(jq.css("margin-top"))||0) + (parseInt(jq.css("border-top"))||0) + (parseInt(jq.css("padding-top"))||0) +
+						(parseInt(jq.css("padding-bottom"))||0) + (parseInt(jq.css("border-bottom"))||0) + (parseInt(jq.css("margin-bottom"))||0);
+
+		}
+		return new Coords( x1, y1, x2, y2 );
+	}
+
+	function jqList2CenterGravity( jqList, dx, dy )
+	{
+		return centerGravity( jqList.toArray().map( function(e,i,a){ return jq2Coords($(e),dx,dy); } ) );
+	}
+
+	/////////////////////
+	// COLLISION CLASS //
+	/////////////////////
+
+	function Collision( jq, cdata, odata, type, dx, dy, ddata, recentCenterOfGravity, mousex, mousey )
+	{
+		if(!recentCenterOfGravity) recentCenterOfGravity=jqList2CenterGravity($(this.collider), dx, dy);
+		if(!dx) dx = 0;
+		if(!dy) dy = 0;
+		this.collision = $(jq            );
+		this.collider  = $(jq.data(cdata));
+		this.obstacle  = $(jq.data(odata));
+		this.direction =   jq.data(ddata);
+		this.type      = type;
+		this.dx        = dx;
+		this.dy        = dy;
+		this.centerOfMass    = recentCenterOfGravity;
+		this.collisionCoords = jq2Coords( this.collision );
+		this.colliderCoords  = jq2Coords( this.collider,  dx, dy );
+		this.obstacleCoords  = jq2Coords( this.obstacle  );
+		if(!mousex) mousex = this.colliderCoords.centerx();
+		if(!mousey) mousex = this.colliderCoords.centery();
+		this.mousex = mousex;
+		this.mousey = mousey;
+	}
+
+	// amount "embedded" into obstacle in x-direction
+	// might be negative or zero if it doesn't make sense
+	// this is used with the delta calculation - if its <= 0, it'll get skipped
+	// dirx is -1 or +1, depending on which way we are orienting things (which way we want to move it)
+	// NOTE: originally, we were taking the collision area into account, but it's easier to recalc embed value
+	Collision.prototype.embedx = function( dirx )
+	{
+		if( this.type == "collision" )
+		{
+			if( dirx < 0 ) /* want to move left  */ return this.colliderCoords.x2 - this.obstacleCoords.x1;
+			if( dirx > 0 ) /* want to move right */ return this.obstacleCoords.x2 - this.colliderCoords.x1;
+		}
+		else if( this.type == "protrusion" )
+		{
+			// if we're embedded in a top/bottom edge, don't move left or right, silly:
+			if( ( this.direction == "N" ) || ( this.direction == "S" ) ) return 0;
+
+			if( dirx < 0 ) /* want to move left  */ return this.colliderCoords.x2 - this.obstacleCoords.x2;
+			if( dirx > 0 ) /* want to move right */ return this.obstacleCoords.x1 - this.colliderCoords.x1;
+		}
+		return 0;
+	};
+
+	// and ditto for y-direction
+	Collision.prototype.embedy = function( diry )
+	{
+		if( this.type == "collision" )
+		{
+			if( diry < 0 ) /* want to move up   */ return this.colliderCoords.y2 - this.obstacleCoords.y1;
+			if( diry > 0 ) /* want to move down */ return this.obstacleCoords.y2 - this.colliderCoords.y1;
+		}
+		else if( this.type == "protrusion" )
+		{
+			// if we're embedded in a left/right edge, don't move up or down, silly:
+			if( ( this.direction == "E" ) || ( this.direction == "W" ) ) return 0;
+
+			if( diry < 0 ) /* want to move up   */ return this.colliderCoords.y2 - this.obstacleCoords.y2;
+			if( diry > 0 ) /* want to move down */ return this.obstacleCoords.y1 - this.colliderCoords.y1;
+		}
+		return 0;
+	};
+
+	// distance from collision to recent center of mass, i.e. it used to be in one place, and we're dragging it
+	// to another, so the "overlap" of some collider happens a certain "distance" from the center of where stuff
+	// used to be...
+	Collision.prototype.distance = function()
+	{
+		var cx1 = this.centerOfMass.centerx();
+		var cy1 = this.centerOfMass.centery();
+		var cx2 = this.collisionCoords.centerx();
+		var cy2 = this.collisionCoords.centery();
+		return Math.sqrt( (cx2-cx1)*(cx2-cx1) + (cy2-cy1)*(cy2-cy1) );
+	};
+
+	Collision.prototype.hash = function(){ return this.type+"["+this.colliderCoords.hash()+","+this.obstacleCoords.hash()+"]"; };
+
+	////////////////////////////////
+	// COLLISION HELPER FUNCTIONS //
+	////////////////////////////////
+
+	// sort so that collisions closest to recent center of mass come first -- we need to resolve them in order
+	function collisionComparison(c1,c2)
+	{
+		var cd1 = c1.distance();
+		var cd2 = c2.distance();
+		return ( ( cd1 < cd2 ) ? -1 : ( cd1 > cd2 ) ? +1 : 0 );
+	}
+
+	///////////////////////
+	// INTERACTION CLASS //
+	///////////////////////
+
+	function Interaction( draggable, options )
+	{
+		this.draggable         = $(draggable);
+		this.obstacleSelector  =   options.obstacle        || ".ui-draggable-collision-obstacle"   ;
+		this.restraintSelector =   options.restraint       || ".ui-draggable-collision-restraint"  ;
+		this.obstacle          = $(options.obstacle        || ".ui-draggable-collision-obstacle"  );
+		this.restraint         = $(options.restraint       || ".ui-draggable-collision-restraint" );
+		var  collider          =   options.collider        || ".ui-draggable-dragging"             ;
+		this.collider          = draggable.find( collider ).andSelf().filter( collider );
+		this.colliderData      = options.colliderData      || null;
+		this.obstacleData      = options.obstacleData      || null;
+		this.directionData     = options.directionData     || null;
+		this.relative          = options.relative          || "body";
+		this.preventCollision  = options.preventCollision  || false;
+		this.preventProtrusion = options.preventProtrusion || false;
+		this.collisions        = $();
+		this.protrusions       = $();
+	}
+
+	//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
+	//
+	// Main handler functions
+	//
+
+	function uiTrigger( _this, widget, eventName, event, ui )
+	{
+		$.ui.plugin.call( widget, eventName, event, ui );
+		_this.trigger( event, ui );
+	}
+
+	function handleInit( event, ui, type )
+	{
+		var w = $(this).data("ui-draggable");
+		var o = w.options;
+	}
+
+	function handleStart(event,ui)
+	{
+		VISUAL_DEBUG = $(this).data("ui-draggable").options.collisionVisualDebug;
+		$(this).data( "jquery-ui-draggable-collision-recent-position", ui.originalPosition );
+	}
+
+	function handleStop (event,ui)
+	{
+		$(this).removeData("jquery-ui-draggable-collision-recent-position");
+		if( VISUAL_DEBUG ) $(".testdebug").remove();
+		VISUAL_DEBUG = DEBUG;
+	}
+
+	// This is the monolithic workhorse of the plugin:
+	//   * At the beginning and end, it sends out all the pre/post-collision/protrusion events
+	//   * In the middle, it both calculates collisions, and prevents them if requested
+	//   * When it's either tried its best, or found a fit, or wasn't required to avoid obstacles, it sends out actual collision events
+	//
+	// Inside the first big loop is the actual "prevention" logic
+	//   * It calculates the "intended position" of everything, checks all the collision logic, and if it needs to,
+	//     then calculates a delta movement to see if that fits, and the loop continues until it either works,
+	//     or an arbitrary iteration limit is reached, just in case it gets in a loop
+	//   * The delta function is described in more detail below
+	//
+	// During all the "trying a new position" and "determining collisions" calculations, it's not using purely the
+	//   current position of the colliders -- it can't because the draggable is now in a new "intended position",
+	//   and with it, all its children, including any collider children
+	//   * So, it keeps track of a dx and dy from known position, and populates a "jquery-collision-coordinates" data value
+	//     that the jquery-collision plugin takes into account during the calculations
+	//   * Also, the Coords() values get populated with these offsets at various times, so that they reflect "intended position"
+	//
+	// Note also that the collider, obstacle, and direction data fields are temporarily overriden (because we need them here,
+	//   and the user may not have asked for them), and then erased and placed where the user wants them, right before
+	//   sending out the collision events
+	//
+	// Note also that the collisions and protrusions requested are "relative" to "body". If the use asked for
+	// something relative, it has to get translated right before sending out the events...
+	function handleCollide( event, ui )
+	{
+		// Note that $(this) is the draggable that's moving - it has a ui.position that moves acording to where
+		// the draggable is "about to move". However, our "collidable" objects might not be the same as $(this) -
+		// they might be child elements. So we need to keep track of recent and present position so we can apply the
+		// "intended" dx and dy to all the moving elements:
+		var rp = $(this).data("jquery-ui-draggable-collision-recent-position");
+
+		if( DEBUG ) { console.log( "handleCollision ******************************************************************" ); }
+
+		if( VISUAL_DEBUG ) $(".testdebug").remove();
+
+		var ctyp  =     "collision";
+		var prec  =  "precollision";
+		var postc = "postcollision";
+		var ptyp  =     "protrusion";
+		var prep  =  "preprotrusion";
+		var postp = "postprotrusion";
+
+		// NOTE: widget is used for uiTrigger, otherwise event-binders don't get a "ui" variable
+		var widget = $(this).data("ui-draggable");
+		var o      = widget.options;
+
+		// List of Interactions -- first one is the main set of args from the .draggable() setup call, rest are multipleCollisionInteractions:[...]
+		var ilist  = [];
+
+		if( o.obstacle || o.restraint ) ilist.push( new Interaction( $(this), o ) );
+		if( o.multipleCollisionInteractions && o.multipleCollisionInteractions['length'] )
+		{
+			var mci = o.multipleCollisionInteractions;
+			for( var i=0; i<mci.length; i++ )
+				ilist.push( new Interaction( $(this), mci[i] ) );
+		}
+
+		if( ilist.length <= 0 )
+		{
+			// Just forget the whole stpuid business - why are we in here, anyways - no interactions to check
+			// Cache the current position anyways, and jump out:
+			$(this).data( "jquery-ui-draggable-collision-recent-position", ui.position );
+			return;
+		}
+
+		var d1 = "ui-draggable-collision-collider-temp";
+		var d2 = "ui-draggable-collision-obstacle-temp";
+		var d3 = "ui-draggable-collision-direction-temp";
+		var di = "ui-draggable-collision-interaction-temp";
+		var d  = event.data;
+		var as = "<div />";
+		if( d && d.as ) as = d.as;
+
+		var e;
+
+		// Try moving things twice the number of colliders times obstacles+restraints, plus 1 original attempt
+		// We need to calculate maxiter here because there may be several levels of interactions
+		// (Honestly, anything will do, just need a reasonable cutoff)
+		var maxiter = 1;
+
+		// Global just-about-to-check-collisions event:
+		for( var i=0; i<ilist.length; i++ )
+		{
+			maxiter += 2 * ilist[i].collider.length * ( ilist[i].obstacle.length + ilist[i].restraint.length );
+
+			if( VISUAL_DEBUG )
+			{
+				ilist[i].obstacle .each(function(){$(this).clone().removeClass().empty().addClass("testdebug").css("pointer-events","none")
+																									.css("background","transparent").css("padding","0px")
+																									.css("border","1px solid black"  ).css("margin","-1px")
+																									.appendTo($(this).parent());});
+				ilist[i].restraint.each(function(){$(this).clone().removeClass().empty().addClass("testdebug").css("pointer-events","none")
+																									.css("background","transparent").css("padding","0px")
+																									.css("border","1px solid magenta").css("margin","-1px")
+																									.appendTo($(this).parent());});
+			}
+
+			if( ilist[i].obstacleSelector )
+			{
+				e = new CollisionCheckEvent( prec, $(this), ilist[i].obstacle, ctyp )
+				uiTrigger( ilist[i].collider, widget, prec, e, ui );
+			}
+
+			if( ilist[i].restraintSelector )
+			{
+				e = new CollisionCheckEvent( prep, $(this), ilist[i].restraint, ptyp )
+				uiTrigger( ilist[i].collider, widget, prep, e, ui );
+			}
+		}
+
+		var origleft = rp.left;
+		var origtop  = rp.top;
+		var origdx = ui.position.left - rp.left;
+		var origdy = ui.position.top  - rp.top;
+		var dx;
+		var dy;
+		var ocl  = []; // list of Collision()'s total
+		var cocl = []; // list of Collision()'s just from collisions
+		var pocl = []; // list of Collision()'s just from protrusions
+		var ccl  = []; // list of Collision()'s just from containment (also a protrusion)
+
+		// Check if there's containment for the draggable:
+		var $cont = $();
+		if( widget.containment )
+		{
+			maxiter += 2; // the main draggable container times twice the number of containers (1)
+
+			var cn = widget.containment;
+			$cont = $("<div />").offset( { left: cn[0], top: cn[1] } )
+													.width(  cn[2]-cn[0]+$(this).width( ) )  // because it had the draggable's size chopped out :-P
+													.height( cn[3]-cn[1]+$(this).height() ); // because it had the draggable's size chopped out :-P
+
+			if( VISUAL_DEBUG )
+				$cont.clone()
+						 .css("background","transparent")
+						 .css("border","1px solid blue")
+						 .css("margin","-1px").css("padding","0px")
+						 .addClass("testdebug")
+						 .appendTo();
+		}
+
+		var deltaCache = {};
+		var iter = 0;
+		while( iter < maxiter )
+		{
+			iter++;
+
+			// Calc offset from recent move, so we can move the objects that are "coming along for the ride" before calculating their
+			// collisions. Otherwise the ui variable only keeps track of the main draggable, not its contents, which may contain
+			// the actual things that collide
+			dx = ui.position.left - rp.left;
+			dy = ui.position.top  - rp.top;
+
+			// Empty the collision containers outside the interaction loop:
+			ocl = [];
+			cocl = [];
+			pocl = [];
+
+			for( var i=0; i<ilist.length; i++ )
+			{
+				ilist[i].collisions  = $();
+				ilist[i].protrusions = $();
+
+				var $c = ilist[i].collider;
+				var $o = ilist[i].obstacle;
+				var $r = ilist[i].restraint;
+				if( DEBUG ) console.log( "trying inter,c,o,r=",ilist[i],$c,$o,$r)
+
+				// Add offset to coordinates before figuring out collisions, because we're basing it on "where its about to go", not "where it is":
+				// (Don't do this for anything but colliders! Applying to obstacles or restrictions or containment screws things up!!)
+				$c.each( function(){ $(this).data( "jquery-collision-coordinates", jq2Coords($(this),dx,dy) ); } );
+
+				var cog = jqList2CenterGravity($c);
+				for( var ci=0; ci<$c.length; ci++ )
+				{
+					// Calculate collisions separately from protrusions, as we might only prevent one or the other:
+					var oc = $($c[ci]).collision( $o, { mode: "collision",  as: "<div />", colliderData: d1, obstacleData: d2, directionData: d3, relative: "body" } );
+					if( DEBUG ) { console.log( "collisions", oc ); }
+
+					// Add the interaction settings to their data, so we can pick it apart later:
+					oc.data( di, ilist[i] );
+
+					// And add the collisions to the interaction:
+					ilist[i].collisions = ilist[i].collisions.add(oc);
+
+					// And if there are any, make the appropriate Collision() objects and add them to the list
+					if( oc.length > 0 )
+					{
+						cocl = oc.toArray().map( function(e,i,a){ return new Collision($(e), d1, d2, "collision" , dx, dy, d3, cog, event.pageX, event.pageY ); } );
+						ocl = ocl.concat( cocl );
+						if(VISUAL_DEBUG) $("<span>c"+iter+"</span>").appendTo(oc.addClass("testdebug").css("position","absolute").css("padding","0px")
+																												.css("border","1px solid black").css("margin","-1").appendTo("body"));
+					}
+
+					// Calculate protrusions likewise:
+					oc     = $($c[ci]).collision( $r, { mode: "protrusion", as: "<div />", colliderData: d1, obstacleData: d2, directionData: d3, relative: "body" } );
+					if( DEBUG ) { console.log( "protrusions", oc ); }
+
+					// Add the interaction settings to their data, so we can pick it apart later:
+					oc.data( di, ilist[i] );
+
+					// And add the protrusions to the interaction:
+					ilist[i].protrusions = ilist[i].protrusions.add( oc );
+
+					// And if there are any, make the appropriate Collision() objects and add them to the list
+					if( oc.length > 0 )
+					{
+						pocl = oc.toArray().map( function(e,i,a){ return new Collision($(e), d1, d2, "protrusion", dx, dy, d3, cog, event.pageX, event.pageY ); } );
+						ocl = ocl.concat( pocl );
+						if(VISUAL_DEBUG) $("<span>p"+iter+"</span>").appendTo(oc.addClass("testdebug").css("position","absolute").css("padding","0px")
+																												.css("border","1px solid magenta").css("margin","-1").appendTo("body"));
+					}
+				}
+
+				// Now remove coordinate offsets before sending events, otherwise event results might futz with em:
+				$c.each( function(){ $(this).removeData( "jquery-collision-coordinates" ); } );
+			}
+
+			if( widget.containment )
+			{
+				// Add offset to coordinates before figuring out collisions, because we're basing it on "where its about to go", not "where it is":
+				// (Don't do this for anything but colliders! Applying to obstacles or restrictions or containment screws things up!!)
+				$(this).each( function(){ $(this).data( "jquery-collision-coordinates", jq2Coords($(this),dx,dy) ); } );
+
+				// Check protrusion from container as well
+				// NOTE: since draggable plugin has already applied containment, if we accidentally move it outside, it won't fix it for us
+				var $cc = $(this).collision( $cont, { mode: "protrusion", as: "<div />", colliderData: d1, obstacleData: d2, directionData: d3, relative: "body" } );
+						ccl = $cc.toArray().map( function(e,i,a){ return new Collision($(e), d1, d2, "protrusion", dx, dy, d3, jqList2CenterGravity($c), event.pageX, event.pageY ); } );
+				if(VISUAL_DEBUG) $("<span>x"+iter+"</span>").appendTo($cc.addClass("testdebug").css("position","absolute")
+																											.css("padding","0px").css("border","1px solid blue").css("margin","-1").appendTo("body"));
+
+				// Now remove coordinate offsets before sending events, otherwise event results might futz with em:
+				$(this).each( function(){ $(this).removeData( "jquery-collision-coordinates" ); } );
+			}
+
+			if( DEBUG ) console.log("checking if we have any collisions at all...");
+			// If there's no collisions, INCLUDING the container, stop now, don't keep doing stuff
+			if( ( cocl.length <= 0 ) && ( pocl.length <= 0 ) && ( ccl.length <= 0 ) ) break;
+
+			var doneAdjusting = true;
+
+			// Go through each interaction -- if any of them break the prevention rule, we aren't done adjusting yet
+			for( var i=0; i<ilist.length; i++ )
+			{
+				if( DEBUG ) console.log("checking adjustments for",ilist[i],"ccl=",ccl,
+																"pc,cl,pp,pl=",ilist[i].preventCollision, ilist[i].collisions.length, ilist[i].preventProtrusion, ilist[i].protrusions.length);
+
+				if( DEBUG ) console.log("checking if we overstepped our containment...");
+				// If we aren't trying to prevent anything yet we SOMEHOW jumped our containment, stop - this shouldn't ever happen, DANGER, WILL ROBINSON!
+				if( ( ! ilist[i].preventCollision ) && ( ! ilist[i].preventProtrusion ) && ( ccl.length > 0 ) )
+				{
+					if( DEBUG ) { console.log( "not trying to prevent anything, but jumped our containment", ilist[i] ); }
+					doneAdjusting = false;
+				}
+
+				if( DEBUG ) console.log("checking if we want to block something we have collided with...");
+				// More specifically, if aren't any collisions that we actually want to prevent, stop -- though we have to think of this in the opposite sense:
+				// if we DO either
+				//   want to prevent collisions yet have a collision or containment failure, OR
+				//   want to prevent protrusions yet have a protrusion or a containment failure,
+				// then DON'T STOP
+				if( ( ilist[i].preventCollision  && ( ( ilist[i].collisions .length > 0 ) || ( ccl.length > 0 ) ) ) ||
+						( ilist[i].preventProtrusion && ( ( ilist[i].protrusions.length > 0 ) || ( ccl.length > 0 ) ) )    )
+				{
+					if( DEBUG ) { console.log( "trying to prevent something that we're still hitting", ilist[i] ); }
+					doneAdjusting = false;
+				}
+			}
+
+			if( doneAdjusting )
+			{
+				if( DEBUG ) { console.log( "done adjusting" ); }
+				break;
+			}
+
+			if( DEBUG ) console.log("calculating delta with ocl,ccl=",ocl,ccl);
+			// Calculate a delta to move, based on collisions+protrusions and containment
+			var d = delta( ocl.concat(), ccl, deltaCache );
+
+			if( DEBUG ) console.log("dx=",d.dx,"dy=",d.dy);
+			// If there's nothing to do, stop -- it shouldn't happen if we had collisions, but...
+			if( d.dx == 0 && d.dy == 0 ) break;
+
+			// Apply the movement, and let the loop run again, to see if our proposed delta movement was any good
+			ui.position.left += d.dx;
+			ui.position.top  += d.dy;
+		}
+
+		dx = ui.position.left - rp.left;
+		dy = ui.position.top  - rp.top;
+		/* deactivated for now - doesn't seem to be needed - may revisit later:
+			// if our new center of gravity is further from the mouse position than the last one, revert
+			var origd = jqList2CenterGravity($c,origdx,origdy).distanceTo( event.pageX, event.pageY );
+			var  newd = jqList2CenterGravity($c,    dx,    dy).distanceTo( event.pageX, event.pageY );
+			if( newd > origd ) { console.log("center of gravity issue: ",origd,newd); } // add this to revert
+		*/
+
+		// If we failed to find a fit, revert to the previous position
+		if( ( iter > maxiter ) ||                             // if we ran out of iterations, tough, revert
+				( ccl.length > 0 ) ||                             // if we ran outside out containment, also revert
+				( o.preventProtrusion && ( pocl.length > 0 ) ) || // if we have a protrusion and are trying to prevent protrusions, revert
+				( o.preventCollision  && ( cocl.length > 0 ) ) )  // if we have a collision and are trying to prevent collisions, revert
+		{
+			if( DEBUG ) console.log("reverting, i=",iter,"maxiter=",maxiter,"cocl=",cocl,"cocl.len=",cocl.length,"pocl=",
+															 pocl,"pocl.len=",pocl.length,"ccl=",ccl,"ccl.len=",ccl.length,
+															 //"newd=",newd,"origd=",origd,
+															 "origdx=",origdx,"origdy=",origdy,"dx=",dx,"dy=",dy);
+			ui.position.left = origleft;
+			ui.position.top  = origtop;
+		}
+
+		// NOW we can go through and actually send out the events -- we couldn't before, because we might have hit
+		//   collisions multiple times during the course of trying to prevent them
+		for( var ci=0; ci<ocl.length; ci++ )
+		{
+			var oc = ocl[ci]; // each ocl[n] is a Collision()
+			for( var oci=0; oci<oc.collision.length; oci++ )
+			{
+				var $occ    = $( oc.collision[oci] );
+
+				// Remove our custom data elements that guaranteed us getting the data we needed
+				var $coll   = $( $occ.data(d1) );
+				var $obs    = $( $occ.data(d2) );
+				var dir     =    $occ.data(d3);
+				var inter   =    $occ.data(di);
+				$occ.removeData(d1).removeData(d2).removeData(d3).removeData(di);
+
+				// And add them back in if the user really wanted them after all
+				if(        inter.colliderData  ) $occ.data( inter.colliderData,  $coll ); // not that useful, since event gets it, but meh
+				if(        inter.obstacleData  ) $occ.data( inter.obstacleData,  $obs  ); // not that useful, since event gets it, but meh
+				if( dir && inter.directionData ) $occ.data( inter.directionData, dir   );
+
+				if( inter.relative && inter.relative != "body" )
+				{
+					var off = $occ.offset();
+					var rel = inter.relative == "collider" ? $coll :
+										inter.relative == "obstacle" ? $obs  :
+																									 $(inter.relative);
+					var ro  = rel.offset();
+					$occ.offset( { left: off.left-ro.left, top: off.top-ro.top } );
+				}
+
+				// Send actual collision event - one per collision, i.e. per collider per collided:
+				if( inter.obstacleSelector  && ( oc.type == "collision"  ) )
+				{
+					e = new CollisionEvent( ctyp, $coll, $obs, ctyp, $occ );
+					uiTrigger( $coll, widget, ctyp, e, ui );
+				}
+				if( inter.restraintSelector && ( oc.type == "protrusion" ) )
+				{
+					e = new CollisionEvent( ptyp, $coll, $obs, ptyp, $occ );
+					uiTrigger( $coll, widget, ptyp, e, ui );
+				}
+			}
+		}
+
+		// Global just-checked-collisions event:
+		for( var i=0; i<ilist.length; i++ )
+		{
+			if( ilist[i].obstacleSelector )
+			{
+				e = new CollisionCheckEvent( postc, $(this), ilist[i].obstacle, ctyp )
+				uiTrigger( ilist[i].collider, widget, postc, e, ui );
+			}
+			if( ilist[i].restraintSelector )
+			{
+				e = new CollisionCheckEvent( postp, $(this), ilist[i].restraint, ptyp )
+				uiTrigger( ilist[i].collider, widget, postp, e, ui );
+			}
+		}
+
+		// And put the resulting ui position in our cache, so that if we keep dragging, we'll know how far stuff moved since this time
+		$(this).data( "jquery-ui-draggable-collision-recent-position", ui.position );
+	}
+
+	// This is the inner-loop collision-prevention function, called maxiter times inside handleCollide()
+	// Its purpose is to determine a single [dx,dy] to move the whole list of colliders and draggable,
+	//   in an attempt to fit them properly. Only one of dx or dy will be non-zero at a time.
+	// The cache argument is a simple object passed in from handleCollide, and is used to store previously-
+	//   -tried movements, so that it doesn't repeat itself.
+	//   * The most common repeat case is if a collider is stuck inbetween two obstacles, and the space isn't big
+	//     enough -- one iteration will have it clear obstacle A, but embed into obstacle B, and the next iteration
+	//     will reverse it, and it will get nowhere quickly.
+	//   * The key for the hash is collider+obstacle coordinates, so the same collider won't avoid the same obstacle
+	//     in the same way twice. (Actually three times, see below.)
+	//   * Note that the value of the hash is either nothing, "tried normal", or "tried reverse"
+	//     * Nothing means it hasn't been tried yet
+	//     * Tried normal means it was tried once
+	//     * Tried reverse means it was tried a second time
+	// How does it determine how to move things around?
+	//   * It calculates an "embed" value, i.e. how far the collider is "embedded" into the obstacle
+	//   * And a direction, either towards center of gravity or away, depending on if it's a collision or protrusion
+	//   * And it returns that
+	// How does it choose what obstacle to avoid?
+	//   * It first sorts all the "collisions" (remember, these are the actual overlapping regions) based on how
+	//     far their centers of gravity are from the last known center of gravity of the draggable itself,
+	//     which was passed in during the creation of the Collision objects
+	//   * It looks at the last one first, so the furthest from the object -- that way, it's going to always reign
+	//     it in towards the last known good value, otherwise "closer" obstacles might keep shoving it away forever
+	//   * Next, it calculates the embed values in the x and y direction, and picks the smallest one -- so if it's
+	//     embedded heavily in the x-direction and only a little in the y, it'll pick the y first (small changes are
+	//     more likely to succeed)
+	//   * If it's a negative value, it tries again, because the embed function does the sanity-checking if we
+	//     tried to move it in a strange or useless way
+	//   * Finally, this is why it tries each "position" twice -- because for each starting position, it tries the
+	//     smaller movement first, but then it tries the larger one. That's why the cache keeps track of the
+	//     "tried reverse" value
+	// In the end, it returns a { dx:_, dy:_ } object, the handleCollision tries moving everything around, recalculates
+	//   all the collisions, and calls this again to see what to do next
+	// NOTE: you can't easily re-calc "real position" from the jquery objects, because they're tagged with data that has
+	//       offsets that are used internally by the jquery-collision plugin, so only use the thisc.*Coords values
+	function delta( collisions, containments, cache )
+	{
+		var c = collisions.concat(containments).sort( collisionComparison );
+		if( VISUAL_DEBUG ) { if(!cache.deltanum){ cache.deltanum = 1; } }
+		if( DEBUG ) { console.log( "collisions, in order: ", c.map(function(e,i,a){return e.collisionCoords.hash();}).join(",") ); }
+		while( c.length > 0 )
+		{
+			// note _pop_ not _shift_. we want to grab furthest collision from center of mass first...
+			// this one is likely the one causing the most problems, because something is embedded deeply into
+			// some obstacle:
+			var thisc = c.pop();
+			var co = thisc.obstacleCoords;
+			var cc = thisc.colliderCoords;
+			var cv = thisc.collisionCoords;
+			var ct = thisc.type;
+			var cd = thisc.direction;
+			var key = thisc.hash();
+			var dirx = ( thisc.type=="protrusion" ? ( cc.centerx() > co.centerx() ? -1 : +1 )
+																						: ( cc.centerx() > co.centerx() ? +1 : -1 ) );
+			var diry = ( thisc.type=="protrusion" ? ( cc.centery() > co.centery() ? -1 : +1 )
+																						: ( cc.centery() > co.centery() ? +1 : -1 ) );
+			var dx = thisc.embedx( dirx );
+			var dy = thisc.embedy( diry );
+			if( DEBUG ) console.log("cv,cc,co,ct,dx,dy,thisc.dx,thisc.dy,dirx,diry,co.centerx,co.centery,cc.centerx,cc.centery,key=",
+									cv.hash(),cc.hash(),co.hash(),ct,dx,dy,thisc.dx,thisc.dy,dirx,diry,co.centerx(),co.centery(),cc.centerx(),cc.centery(),key);
+			var tryToAdjustDX = ( dx < dy );
+			if(      key in cache && cache[key] == "tried reverse" ) { if( DEBUG ) console.log("but already tried reverse too...");
+																																 continue; }
+			else if( key in cache && cache[key] == "tried normal"  ) { if( DEBUG ) console.log("but already tried this...");
+																																 tryToAdjustDX=!tryToAdjustDX; cache[key]="tried reverse";
+																															 }
+			else                                                     { cache[key]="tried normal"; }
+			if( tryToAdjustDX )
+			{
+				if( VISUAL_DEBUG ) { $("<span>"+thisc.direction+"d"+cache.deltanum+".dx="+dx+"*"+dirx+"</span>").css("color","black").addClass("testdebug")
+														 .css("position","absolute")
+														 .css("white-space","nowrap").offset( { left: thisc.mousex, top: thisc.mousey + 20*(cache.deltanum-1) } ).appendTo("body"); cache.deltanum++; };
+				if( dx <= 0 ) { c.push(thisc); continue; }
+				return { "dx":dx*dirx, "dy":0 };
+			}
+			else
+			{
+				if( VISUAL_DEBUG ) { $("<span>"+thisc.direction+"d"+cache.deltanum+".dy="+dy+"*"+diry+"</span>").css("color","black").addClass("testdebug")
+														 .css("position","absolute")
+														 .css("white-space","nowrap").offset( { left: thisc.mousex, top: thisc.mousey + 20*(cache.deltanum-1) } ).appendTo("body"); cache.deltanum++; };
+				if( dy <= 0 ) { c.push(thisc); continue; }
+				return { "dx":0, "dy":dy*diry };
+			}
+		}
+		return { "dx":0, "dy":0 };
+	};
+
+})(jQuery);