# Havok: Incorrect scaling of mesh when dragging with constraint **URL:** \ **Category:** Bugs\ **Tags:** physics, drag, bug, havok\ **Created:** [April 29, 2024, 8:35am UTC](https://forum.babylonjs.com/t/havok-incorrect-scaling-of-mesh-when-dragging-with-constraint/50113 "2024-04-29T08:35:43Z")\ **Posts on this page:** 10\ **Page:** 1
**Author:** ![kzhsw](https://avatars.discourse-cdn.com/v4/letter/k/848f3c/32.png) [@kzhsw](https://forum.babylonjs.com/u/kzhsw)\ **Post date:** [April 29, 2024, 8:35am UTC](https://forum.babylonjs.com/t/havok-incorrect-scaling-of-mesh-when-dragging-with-constraint/50113/1 "2024-04-29T08:35:43Z")
OS: Windows 10 Browser: Chromium and Firefox Playground: > **[Babylon.js Playground](https://playground.babylonjs.com/#112FXI%239)** > > Babylon.js playground is a live editor for Babylon.js WebGL 3D scenes Desc: I’m trying to drag a mesh with physics enabled with constraint, to make dragging more natural, but when the mesh being dragged, the scaling of meshes goes wrong. Video: ---
**Author:** ![Joe\_Kerr](https://sea2.discourse-cdn.com/flex024/user_avatar/forum.babylonjs.com/joe_kerr/32/39017_2.png) [@Joe\_Kerr](https://forum.babylonjs.com/u/Joe_Kerr)\ **Post date:** [April 29, 2024, 10:40am UTC](https://forum.babylonjs.com/t/havok-incorrect-scaling-of-mesh-when-dragging-with-constraint/50113/2 "2024-04-29T10:40:37Z")
> [@kzhsw](#): > > the scaling of meshes goes wrong If it can help you in debugging: I have seen this error pattern with messed up quaternions, too. So not necessirly scaling. ---
**Author:** ![kzhsw](https://avatars.discourse-cdn.com/v4/letter/k/848f3c/32.png) [@kzhsw](https://forum.babylonjs.com/u/kzhsw)\ **Post date:** [April 30, 2024, 12:43am UTC](https://forum.babylonjs.com/t/havok-incorrect-scaling-of-mesh-when-dragging-with-constraint/50113/3 "2024-04-30T00:43:11Z")
Using buildin inspector of playground, the changing of scaling can be observed like this: ![scaling](https://us1.discourse-cdn.com/flex024/uploads/babylonjs/original/3X/2/7/27bf0f3af78a8d15e073ec7ab0cbdf544e4edaea.png) ---
**Author:** ![sebavan](https://sea2.discourse-cdn.com/flex024/user_avatar/forum.babylonjs.com/sebavan/32/57_2.png) [@sebavan](https://forum.babylonjs.com/u/sebavan)\ **Post date:** [May 2, 2024, 12:48am UTC](https://forum.babylonjs.com/t/havok-incorrect-scaling-of-mesh-when-dragging-with-constraint/50113/4 "2024-05-02T00:48:31Z")
Assigned @Cedric on May 2, 2024, 12:48am UTC ---
**Author:** ![Cedric](https://sea2.discourse-cdn.com/flex024/user_avatar/forum.babylonjs.com/cedric/32/2742_2.png) [@Cedric](https://forum.babylonjs.com/u/Cedric)\ **Post date:** [May 13, 2024, 2:43pm UTC](https://forum.babylonjs.com/t/havok-incorrect-scaling-of-mesh-when-dragging-with-constraint/50113/5 "2024-05-13T14:43:00Z")
This is an interesting bug! yes, it looks a bit like non normalized quaternion. I’ll take a closer look asap ---
**Author:** ![Cedric](https://sea2.discourse-cdn.com/flex024/user_avatar/forum.babylonjs.com/cedric/32/2742_2.png) [@Cedric](https://forum.babylonjs.com/u/Cedric)\ **Post date:** [May 14, 2024, 3:01pm UTC](https://forum.babylonjs.com/t/havok-incorrect-scaling-of-mesh-when-dragging-with-constraint/50113/6 "2024-05-14T15:01:39Z")
I’ve found a fix. Please test it when the snapshot is available @kzhsw > > > Fixes for : > \- https://forum.babylonjs.com/t/havok-plugin-dispose-returns-error…/50087 ---
**Author:** ![Cedric](https://sea2.discourse-cdn.com/flex024/user_avatar/forum.babylonjs.com/cedric/32/2742_2.png) [@Cedric](https://forum.babylonjs.com/u/Cedric)\ **Post date:** [May 14, 2024, 3:01pm UTC](https://forum.babylonjs.com/t/havok-incorrect-scaling-of-mesh-when-dragging-with-constraint/50113/7 "2024-05-14T15:01:41Z")
Unassigned @Cedric on May 14, 2024, 3:01pm UTC ---
**Author:** ![kzhsw](https://avatars.discourse-cdn.com/v4/letter/k/848f3c/32.png) [@kzhsw](https://forum.babylonjs.com/u/kzhsw)\ **Post date:** [May 15, 2024, 12:51am UTC](https://forum.babylonjs.com/t/havok-incorrect-scaling-of-mesh-when-dragging-with-constraint/50113/8 "2024-05-15T00:51:59Z")
The scaling does not change now with this pr, but the box jumps out and does not stop moving even after pointer released. Is there something wrong with my playground or more fixed needed? > **[Babylon.js Playground](https://playground.babylonjs.com/?snapshot=refs%2Fpull%2F15097%2Fmerge#112FXI%239)** > > Babylon.js playground is a live editor for Babylon.js WebGL 3D scenes ---
**Author:** ![Cedric](https://sea2.discourse-cdn.com/flex024/user_avatar/forum.babylonjs.com/cedric/32/2742_2.png) [@Cedric](https://forum.babylonjs.com/u/Cedric)\ **Post date:** [May 15, 2024, 7:40am UTC](https://forum.babylonjs.com/t/havok-incorrect-scaling-of-mesh-when-dragging-with-constraint/50113/9 "2024-05-15T07:40:05Z")
Yes, I think it’s related to the way the constraint is set. it pushes the box to a position that generates collisions. ---
**Author:** ![kzhsw](https://avatars.discourse-cdn.com/v4/letter/k/848f3c/32.png) [@kzhsw](https://forum.babylonjs.com/u/kzhsw)\ **Post date:** [May 15, 2024, 8:52am UTC](https://forum.babylonjs.com/t/havok-incorrect-scaling-of-mesh-when-dragging-with-constraint/50113/10 "2024-05-15T08:52:18Z")
Could you provide some example on how to set the constraint correctly? I’m quite new to havok.