Unreal Engine Issues
Unreal Engine Issues
Character jumping can become permanently blocked under subpar net conditions
UE - Gameplay - Player Movement - Dec 8, 2023Problem Under laggy networking conditions, if the user rapidly presses the jump button the character can at some point stop responding to jump input. Initial Thoughts It looks like there's a logi ...
Vehicle Template with Thruster Configuration will be affected by force relative to the distance from the origin
UE - Simulation - Physics - Mar 18, 2025Vehicle Template vehicle with added Thruster Configuration to its VehicleMovementComponent will be affected by force relative to the distance from the origin. At around 200000 the force is enough to ...
Iris - large fast arrays serialize multiple elements when only one is dirtied
UE - Networking - Iris - Apr 8, 2025This seems to be a result of how the changemask is handled for fast arrays. Because the changemask is a fixed set of bits (defined by IrisFastArrayChangeMaskBits), a single bit can represent multipl ...
Incorrect number of vertices displayed by ProfileGPU command in Cascade particles
UE - Niagara - Dec 9, 2021This issue was reported by the licensee, but it's possible that the number of vertices in the particles is higher than it really is. ...
Issues changing physics properties on destructible meshes
UE - Simulation - Physics - Destruction - Oct 15, 2015Numerous issues when manipulating destructibles. 1) Changing collision response pre-fracture will not affect chunks post-fracture 2) Changing collisions response pre-fracture will prevent damage f ...
Playing sequences in reverse snaps after sequence has first ran
UE - Anim - Sequencer - Dec 29, 2016I first came across this bug when I was working with Actor Sequences and noticed that the door I had opening would snap back when I tried to close it. Later I discovered that the issue was with play ...
Mouse Events cannot be treated as Touch on Android Apps on Chromebook
UE - Platform - Mobile - Mar 18, 2019A licensee reported an issue where mouse events are not able to be used as touch events on Android apps. This was specifically reported on and tested on Chromebooks. After working with Chris Babcock ...
Soft Object unloads after some time when stored in a Blackboard
UE - AI - Mar 11, 2020When loading a Soft Object and directly placing the loaded Object into a Blackboard, after about 2 minutes the Object will unload and become null inside the Blackboard. This issue only occurs in a p ...
Translucent materials with Modulate blend mode disappear with down-res translucency enabled
UE - Graphics Features - May 28, 2024Reported from this UDN: https://udn.unrealengine.com/s/question/0D5QP00000MLlco0AD/active-dtr-doesnt-render-beforedofmodulated-materials?fromCase=1 The problem is that, except in very specific circ ...
Calling GetMaterial during compile on load can cause the material shader to fail to compile
UE - Rendering Architecture - Materials - Oct 4, 2024Calling UStaticMeshComponent::GetMaterial() during a Blueprint compile on load can cause the Material shader to fail to compile because GetMaterial will trigger a PostLoad call on that Material and ...