So this is the strangest thing… I’m trying to create/use/shoot a basic projectile. Nearly everything is default, have scene component, projectile static mesh and projectile movement component. What’s happening is, if I set the projectiles velocity as the projectiles speed, when I run in simulation mode, I can see the gizmo shoot with the velocity but the static mesh simply falls straight to the ground. If I use impulse for the projectile speed and no velocity, the mesh shoots as expected but the gizmo falls to the ground. I’m assuming the gizmo is representative of the pivot point which means that somehow the pivot point is separating from the mesh!!
One might say just match up the velocity and impulse but they are 2 different types of measurements - you can’t just do 1000 impulse and 1000 velocity. I don’t know if this is a bug in 4.11 or if I’m doing something wrong. I don’t remember having this problem in other versions.
I was hoping someone might have some insight with this?? I will update this post with a few images when I return to my PC but hoping you can help without them!
Thanks for the reply. I added a collage of images for what I’m experiencing. The setup is truly very simple at this stage. Press a UMG Button to fire, which calls the seen Fire Weapon function, which simply spawns a projectile using the transform of a bone (Muzzle) that is part of the “gun” I’m shooting from (the gray barrel seen on side of image.) Very simple setup indeed. I’m one of those developers who tests everything along the way so I don’t leave scratching my head wondering where the problem is because I coded too much. Plus, this is for a mobile app so requires constant testing on device. What you see in the images is PIE and all mobile functionality (tilt/gravity/movement) of the craft have been disabled in order for me to test in the PIE. I start the PIE, pause, eject, move off to side a bit, click the “Fire” button to spawn the projectile, select the in world projectile to hi-lite it then hit resume to see it’s path. I’m confident it’s not because of the “Simulation” mode I’m testing in because I noticed the behavior during normal play/testing as well on both PIE and Device. Thanks again for the help!
Just for completeness I will explain what the (my) issue was:
The first issue was I had Simulate Physics enabled on the projectile mesh. Disabling this seemed to fix the issue, there was no separation of pivot & mesh. Problem with this is my projectile is a bullet which needs Hit Detection. Even with the box ‘Simulation Generates Hit Events’ ticked true, it does not work if ‘Simulate Physics’ is off.
The true underlying issue is, as with most BP’s, I had a ‘Scene’ component with the projectile mesh as a child of that then had the Projectile Movement component, which can not be a child of anything and affects the blueprint Root component. The pivot separation I was seeing was not the pivot of the mesh rather it was/is the root component (the BP) that was separating from the mesh. Seeing as the mesh is a child of the ‘Scene’ component, when you select Simulate Physics, the parent, in this case the Scene component, does not know it needs to simulate physics as parents don’t inherit from children.
To fix the issue, I simply deleted the ‘Scene’ component and used the static mesh component (projectile) as the root component. Now there is no separation and I can still have Simulate Physics enables so the Hit Events work properly as well. Hope someone can find this helpful in the future!
