Following code will clip objectBig to the size of objectSmall on the second update call:

var stage = new createjs.StageGL(…, {directDraw:false})
objectSmall.filters = […]
objectBig.filters = […]
stage.addChild(objectSmall, objectBig)
// first update call
stage.update()
// second update call
stage.update()

https://codepen.io/adabru/pen/aaOxZb?editors=1000

The error comes from following code:

On the first update call, every item will go into the if (item.bitmapCache === null) branch and the bounds variable will be assigned to the correct bounds. On the second update call however, no item will go into this branch as bitmapCache is assigned for each of them. Therefore bounds is assigned by the line bounds = bounds || item.getBounds();. As bounds is null on declaration, the first item will get its correct bounds assigned with this statement. BUT as bounds is declared as var and therefore its scope is for the entire function, the next items will pick the first item's bounds and thus be clipped if they are smaller than the first item.

One fix could be to use var bounds = null;. The fix in this pull request is using let bounds; instead to block-scope the bounds variable.

See https://codepen.io/adabru/pen/rZVZyX?editors=1000 .

let syntax is not handled by grunt-contrib-uglify default branch, so this pull request also changes this dependency to its grunt-contrib-uglify-es branch (https://github.com/gruntjs/grunt-contrib-uglify/tree/harmony).

My workaround at the moment is using a fork of this repo. I hope this issue can soon be fixed in master.