DnD with Float Performance Problem

[Paitum]

Overview

I am using angular-gridster as part of a Dashboard solution. I discovered that certain movements are causing a significant performance problem that I believe can be avoided.

Problem Statement

When dragging a gridsterItem, it is possible for a lot of unnecessary processing to be triggered that will result in no change to the gridster layout. This can occur because the movements may be countered by the floating logic.

Animation

In the following animation, notice how fast the animation can be, followed by a significant performance reduction when gridster calls moveOverlappingItems to items that then floatItemUp back up:

Chrome Profiler

572.4 ms8.47 % 572.4 ms8.47 % getItems
326.4 ms4.83 % 326.4 ms4.83 % floatItemUpRow
326.4 ms4.83 % 326.4 ms4.83 % moveOverlappingItems
165.7 ms2.45 % 165.7 ms2.45 % putItem
131.7 ms1.95 % 131.7 ms1.95 % moveItemDown
131.7 ms1.95 % 131.7 ms1.95 % moveItemsDown
131.7 ms1.95 % 131.7 ms1.95 % moveOverlappingItems
114.8 ms1.70 % 114.8 ms1.70 % moveItemDown
114.8 ms1.70 % 114.8 ms1.70 % moveItemsDown
114.8 ms1.70 % 114.8 ms1.70 % moveOverlappingItems
114.8 ms1.70 % 114.8 ms1.70 % putItem
114.8 ms1.70 % 114.8 ms1.70 % setPosition
114.8 ms1.70 % 114.8 ms1.70 % positionChanged
114.8 ms1.70 % 114.8 ms1.70 % $digest
114.8 ms1.70 % 114.8 ms1.70 % $apply
114.8 ms1.70 % 114.8 ms1.70 % drag
114.8 ms1.70 % 114.8 ms1.70 % mouseMove
114.8 ms1.70 % 114.8 ms1.70 % doEvent

Thoughts

If the framework could determine that the dragging item is not introducing a substantive change, due to the float behavior, then it could avoid all of the unnecessary processing.