ScrollBar and PointerBlocker

Hi there,
in my application i’ve a GUI with a grid inside a ScrollViewer that can overlap some meshes.
These meshes are pickable and can react to mouse move events. When i show the GUI i don’t want that the user could interact with meshes, so i set isPointerBlocker = true on all the GUI elements, and generally it works…till now :slight_smile: I found that if the user moves the scroll bar the PointerOver event is triggered anyway by the mesh. Is it a bug or am i forgetting something?
This is a PG to repro the issue:
The sphere changes the colour when mouse is over, and with no GUI that overlaps. But if you move the sliding bar, the PointerOver event is not blocked.

Maybe @DarraghBurke can help?

Hello! Apologies for this not having been answered, sometimes things slip by us :slightly_frowning_face: I’m not sure about the pointerBlocker behavior (@DarraghBurke will be more qualified to know if this is expected or not), but I thought about an alternative solution without it, you could set the mesh isPickable property as false when the pointer enters a control, and to true when the pointer leaves: Test scrollbar and pointerblock | Babylon.js Playground (


Hey, so sorry about the delay in getting back to you! I missed the original ping on the forum.

Here is a PR to resolve this issue: [GUI] Block pointer events to scene when pointer is captured by darraghjburke · Pull Request #12400 · BabylonJS/Babylon.js (

What it will do is block pointer events from being passed to the scene when the pointer is captured (for example, if you’re dragging on a scrollviewer or slider).


Thank you, don’t worry for the delay it’s not a problem. I needed only confirmation that was a bug :wink:

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