Instanced Static Meshes in Blueprints collision translates incorrectly

If you create a blueprint with an instanced static mesh. Spawn it in the world. And then translate it after it has spawned, it’s collision will not have moved even though the visible mesh will have moved.

I first produced this using the Top Down Sci Fi Asset Set. I can reproduce this in a new project.

This is causing issues for us as our map generation system relies on moving blueprint tiles after it has spawned.

HI Deepfried,

Can you show me your blueprint setup?

I used the third person blueprint default. I imported the top down sci fi asset bundle. Deleted all the obstacles and floor and moved the player start to just above the origin:

Created this blueprint:

And then put this in the level blueprint:

And then when I run I get this:

Does this only occur with the sci fi assets or is it any asset that you utilize?

I made a new 3rd person with the starter content and used the Shape_Cube. The same effect happened. I also noticed another bug:
If I set the instancedStaticMesh scale under A here:

Then it changes the scale in the blueprint viewport, however when you run the scale has not been changed. You have to set the scale on each individual instance in the array (B).

Are your meshes set to static or movable?

As in the picture they are set to movable.

Do you see the same results if you set the object with your make transform?

If you mean if I set the initial spawn location, it can spawn anywhere correctly, its any translation after spawning (using set actor location, or set actor transform) that causes it to disconnect display from collision.

Even moving it in editor causes it to move without its collision.

Hi Deepfried,

I was able to reproduce this and have entered a bug report, UE-13673 to be assessed by the development staff.

that’s the second bug that’s a big thorn in my side. Really hope they’re addressed next patch :slight_smile:

Wish I had searched for this a bit more before spending 10 hours on this :expressionless:

Going to watch that bug report, it’s make or break for my project.

Did this get fixed yet?

Hi ,

Unfortunately this report is still under assessment. I do not have a timeframe of when a fix will be implemented.

Priority upgrade please

Oh, please fix this! I need this in 4.11.

yes, you put the mesh where it needs to be, then delete it and create a new mesh at that location without translating it

Does anyone here have something like a workaround to make the ISMC update the collision correctly?

Looks like there are no real workarounds, as all of them demolish performance. I’d like to bump up the interest in this.

Hi! Do you have any news?