Please recommend a JQuery plugin that handles collision detection for draggable elements

Question

We're using the Draggable JQuery UI plugin and need to disallow overlapping among our elements. We could write some collision detection ourselves but would prefer to use a tested package. Any suggestions?

Answer 1

You can try jquery-collision plus jquery-ui-draggable-collision. Full disclosure: I just wrote and released these on sourceforge.

The first allows this:

var hit_list = $("#collider").collision(".obstacle");

which is the list of all ".obstacle" that overlap "#collider".

The second allows:

$("#collider").draggable( { obstacle: ".obstacle" } );

Which gives you (among other things), a "collision" event to bind to:

$("#collider").bind( "collision", function(event,ui){...} );

And you can even set:

$("#collider").draggable( { obstacle: ".obstacle", preventCollision: true } );

to prevent "#collider" from ever overlapping any ".obstacle" while dragging.