Hi,
I have a problem with my character, he cannot walk through the open door. It’s not the door frame because without the door I can pass.
Here my door BP :
This is my door mesh :
This is the door open with the collision activated in the editor (I see no change without the door) :
Here a video of what is going on
I try multiple things like changing the collision, changing the size of the character…
I tried all this link :
If you have any ideas I take it !
Thanks in advance 
If you want to actually use physics, the collision box needs to be the root component, I believe ( don’t actually know because I don’t use physics ).
If you are just opening the door with a blueprint, the collision box is not parented to the door, and so will still be in the doorway after the door has opened, blocking the player.
Any good? 
You might want to look at the Collision Bounding Box of the character, most defaults use a capsule with a large margin. Create a simple mesh that can be applied to reduce the margins. I can see that the ‘doorway’ doesn’t use a lot of hulls to create the opening, add another 4 vertices may also help, to form a smoother arch as opposed to a triangle.
In the box below the selection box, where you have chosen Use Complex as Simple, drop a copy of the Root mesh of the character in there. The engine will simplify that mesh so it matches the character and not some capsule.
Then there is the Collision engines Margin buffer added to that. Think of your character wearing a tall top hat.
I do that all the time, for Tree Meshes, using a simplified mesh of the trunk and branches, not leaves, for collision.
I am not sure if you can edit the capsule in Unreal, to make it shorter. Alternatively, use simple boxes as collision for your walls, with nothing over the doors, so the thing stopping them from passing through, will be the actual door collider itself. You don’t need collision above the door itself. That will negate the editing or swapping of the character collision capsule. Oh it will also lessen the camera hitting you in the head each time the player passes through.
Just a thought.
Thanks for the answer !
I don’t want to specially use physics, I was trying many thing even physics ^^
I try to root the collision box to the door mesh but it’s doesn’t work 
I just want my chacter to go through ahah
Thanks for the post !
Tried this, I needed to reimport the character to have it in static mesh, I had only skeletal mesh, physics asset and skeleton. But it’s doesn’t work, with it, it’s like an invisible wall.
In the physics of my character, I changed the collision to make it smaller.
Right now, nothing works
But perharps I do something wrong (obviously).
When, I open the door, and try to go through, it’s looks like the physics of the door stay in place.
(post deleted by author)
So the door sounds to be the problem. You have created a static mesh collider for the Door Object.
Does it use the same pivot point?.
Is it attached to the actual door root mesh?
Is it created using the Mesh Editor in the engine?
Is the Door set as a Static object (small tick box, top right of the Inspection Window)?
Have you deselected the option ‘Can the Character/Player walk upon’ physics function?
Have you checked out the scene in Wireframe Mode, to see if there is the wall mesh blocking the way? Sometimes the mesh doorway will actually be a Hole in the Mesh, not an opening, Physic engines do not deal with holes well. If so, remove the threshold connections, so you have an actual Arch. You can check that in Wireframe Mode.
The characters Collision mesh, need only be a rectangle, or cylinder, it is about the actual size that is the key.
Its a bit of a long checklist, but it will eliminate several conditions that can cause the problem.
You may want to simply use a Volume trigger to open the door when the character enters that space, and not have any collision physics attached to the door at all. You can also set conditions like whether the character has picked up a key or something as a condition as well.
List of what I tried :
I change the pivot point and it’s good
Yes, The door is rooted at the door frame, and the collision box is rooted at the door
Are you talking about the collision system ?
No, His mobility is “Movable” in the BP
Do you mean “Can Character Step Up On” ? If yes, it’s a no, he can’t. If no, I don’t know where is this function
I checked that, and I don’t think it’s the character, in collision mode, the character seems okay
If you need anything, like pictures or videos, tell me I will join it
Thanks for the help
My last comment was perhaps the most useful if Physics are an issue. The same trigger volume can also trigger a timeline sequence, that swings the axe, that strikes the door, door swings open… Could be a neat solution.
I did something similar with a Space Port Door animation opens, when the player is within a Volume, and has 4 Codes collected in the scene. Created the timeline, with the animation, a condition to check all the codes had been collected… player passes through the port. No Physics in the whole show. Well apart from the blocking prim, should the code count be low.
You can attach and use the same timeline sequence for every door, just place it on a Non-Root object, so it will be in Local Space, not World Space, otherwise it will be World Coordinates specific.
If you can zip up the project under 1GB, I will take a quick look. You can put it on google docs, or whatever and PM me a link…
Looks like your also testing multiplayer… can the other character walk through the door?
Based off the jittering back and forth i’d say you opened the door on the client and not on the server
at least in my experience when it’s collision related you usually just stop point blank… The jitteriness tells me that the client sees the door as open, starts to pass through then the server says woah… you can’t be there that door is closed and pushes you back, the only reason you get even a single step past like that is the 1-2 frames before the server verified your location ( the predictive part of the Character movement component )
If this is the case… when you call for the door to open it needs to “Run on Server” as well… tho if your using an Interface to do this, it’s worth noting you’ll have to do the line trace as the server, as when an interface is called it executes the target BP as Either Client or Server depending which called the interface
I will try to export you only the BP. Right now the project weight 32GB ahah
Ah yes, I will check that, good point, thanks !
Wow, I think you solved the problem… I played in “Listen as Server” and I change the replication system, and right now, it’s working, I can go through. You were right, it was a client/server problem who for the client, the door was open but not for the server.
Thanks a lot !
And thanks for the others too !
I hope it will still working !
If you make a new empty project, then just migrate the level to that, it will be small.
