Simulate physics not working in BP

Hi. I have a problem. In my BP, (Actor) I have scripted the hay to simulate physics when activated. The physic work if sent manually, but that’s no use. I’m using 4.14.

BP :

The model has working collisions, so I just think its the BP going wrong.

It’s hard to tell what the nodes are trying to do. But by looking at the image, I can see you only have one SetSimulatePhysics node and it’s set to always False.

Also, you sure your mesh is not set to Static or Stationary on the mobility options? In 4.14 and after, those mobility options also affect movement, not just baked light and shadow calculations.

You can select the Q node and press F5 to add a break point. When you play in editor and press 1, the game will pause and show you the q event, and you can go step by step and see what is being executed.

If you add the break point and in fact it is not being halted, then you know it was that that is the issue.

Thanks, because of you I managed to pinpoint the problem. It turns out that “Q” button press is not working.

Ok, so I just encountered the same kind of problem. I can’t set a mesh to simulate physics through BP and can only set it through editor properties.
But I solved it.
What I did was I went to the Physics Asset the mesh is using and set the “Physics Type” property of the collision bodies to be “Default” instead of “Simulate”. Now I can enable and disable physics simulation at runtime through BP.

Note to devs: I think it must be mentioned somewhere in the “Set Simulate Physics” function’s description.

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Hnomer could you be more specific? Screenshots maybe? I can enable physics from the editor window including gravity but I cannot enable from the BP.

You must open the Physics Asset editor, then select a collision body from the hierarchy, then you should be able to see the Physics Type property on the Details panel which is by default should be on the right side of your screen. Set the Physics Type to Default (see screenshot). After you’re done with this, you should be able to change Physics settings using SetSimulatePhysics node. Note that it will only change the behavior of the collision bodies with Physics Type set to Default.
I honestly don’t know how I can explain it better.