there seems to be 2 problems with unreal5 right now.
1-Substepping works differently. It does not work as we expect and simulation gets erratic at low frame rates. On the other hand async tick option is now available which sounds like the system in unity. It works allright(still experimental feature) and it’s the obvious choice to pick when it comes to replication.
2-Sometimes vehicles suddenly stop/freeze while flying. This is a very strange problem and it looks like a physics bug to me. i discovered that if you disable downforce in aerodynamics component this problems goes away but it doesn’t make sense since we just apply some extra force to the rigidbody.
When we address these problems the rest is easy to port we hope…
I am currently having trouble setting up truck with trailer (from marketplace). The truck head is connected to the trailer using a PhysicsConstraint. Everytime the physicscontraint is inserted, the bodies (trailer and head) will explode. The same setup work nicely with UE4 vehiclemovement.
I have tried quite a lot of ‘disable collision’ everywhere between skeletalmesh and the staticmesh (the marketplace creator is using staticmesh just for the visual, and skeletalmesh for pure physics ). But it is still no to avail.
Any clue on how to solve this? While typing, I have this one idea - maybe I will ask an artist to ‘combine’ the skeletalmesh and staticmesh - this has been my setup before.
I tried changing the car mass to 3000 (Actually 1400), suspensions,etc… but nothing seems to fix the problem. No matter front or side collision, the car looks always lightweight no matter the mass i set to the car. Tried with relaxation dumper / downforce and other stuff tha in some way does it less but the car driving got impossible. Same if i set center of mass is -0.5, fixes mostly but car driving is so weird.
I tried addimpulse on collision or every tick with force,etc… but nothing like that worked.
Tested with other cars and realized there is one where it never happens, no matter the speed, i set same params,etc… at the end was the custom collision. Changed for the other car and worked. Here the difference between one and other, maybe this can help to others with same problem.
So, what im gonna do is edit the collider to make the front part similar as the other and test various things to see what works best to avoid this kind of problems.
No worries… I will only jump to UE5 maybe next year. Waiting for it to settle dust - by then, the Chaos could be much more stabilized.
But I know there will be lots of people asking for UE5 update…
I think it is not helping much - source code is not there and it is Unity not UE4. UE4 have different code and bugs too. And probably the only sound solution is to combine everything into the skeletalmesh (now blank skeletalmesh + staticmeshes - I dont know why the author did that way).
looking forward to the final version