Attach actor with physics

Hi

Activating “Simulate physics” on a blueprint does not seem to have an effect?

Similar to Zelda games, I have a stick I can pick up. It currently does not have physics, and the pick-up works fine, but glitches through the floor of elevators if placed on the ground. So, I would like the stick to have physics, but the problem then is that I can’t pick it up. I can see in the outliner that it gets attached, but not transformed to the socket. I have tried to deactivate physics before attaching it to the socket by giving the stick a tag first, but that does not work for some reason.

Any suggestions to how to do this interaction? Seems like a very common thing to do in games. I guess you could attach the stick to the ground below it, but that limits the possibility of having platforms that can flip upside down.

I have followed these forum posts, but none worked for me:

My Blueprints for attaching/detaching actors:


Video with example:

Hey there @Heisjegg! You had the right idea when you tried to disable the physics then pick up, and enable it after you drop it. That said, if you do anything with physics while moving anything with translations in the same frame, things will always break. An empty delay node will delay it to next frame.

image

Hope this helps!

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The issue with this is that your pickup has a Scene component as the root component, so when you enable physics the static mesh gets detached from its parent, you can read the highlighted description.

The solution is to make the static mesh the root component or after you disable physics attach the static mesh back to the scene component.

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Thanks a lot, I will try this! Great to understand more how UE actually works

Never thought about reading the nodes description, thanks for pointing that out! I will test this by making the mesh the root, and come if this solved it

The solution was like you said Kaidoom, to make the static mesh the root, but also attach to the players socket again after physics are disabled. Thank you so much for the help! Also, when dropping the item, I have to delay turning on the physics again, or else it will collide with the player to soon and catapult itself beyond the horizon.

Player blueprint:



Pickup item blueprint: