Hello, I am using Unreal Engine 5.5, and I am trying to create a pick-up and drop system using a Blueprint interface. First, I will explain the mechanic, then address the issue, and finally provide the code and videos for better understanding.
The pick-up system works as follows:
In the BP_FirstPersonCharacter, I have used the node “Left Mouse Button.” On Pressed, it shoots a line trace from the player’s camera and checks if the hit object implements the interface. If it does, I call the “Sim Physics (message)” function from the interface, which has a boolean input that I set to false (unchecked). Then, I attach the actor to a component. On Release of the left mouse button, I call the “Sim Physics” function again and set the boolean to true, then detach the actor.
This is the behavior I am aiming for, and I believe it is simple enough. I have placed an actor with the interface in the level, and the system works the first time I try it. However, after the initial use, it stops working. It seems that after enabling simulate physics, the actor won’t attach or move anymore. I have also tried using the “Set Actor Location” node for testing purposes, but this did not work either. It’s as if the mesh is in a static state instead of being movable.
Here is all of the code.
Pick-up and drop item code:
Inside interface:
Item actor code:
This is a video of the issue:
I have also tested the same code in other versions of Unreal Engine, such as 5.4 and 5.1, and it still produces the same result. I’m not sure if this is a bug in Unreal Engine or if I’m missing something. If anyone knows what is causing the issue, please let me know.
Thank you in advance!
