Unreal Engine Issues
Unreal Engine Issues
FBX Import - Morph target normals not correctly applied when imported as LOD 0
zComponent - Archive - Nov 27, 2025This is a regression since 5.5 with skeletal meshes where morph target normal/tangent deformation only works when a mesh is imported as a LOD of an existing skeletal mesh, but not when imported as L ...
Material Stats returning Incorrect Sampler and Instruction Counts
UE - Graphics Features - Mar 9, 2017When creating and modifying a material, the base Texture Sampler count and instructions are returning incorrect values. In 4.14.3 whenever you create a new material the Texture Sampler count is 0/1 ...
World Partition Editor minimap build failed
UE - Engine Scaling - Streaming - Aug 10, 2023The issue was reproduced when building a minimap for an open world level with no Actors with "Is Spatially Loaded" enabled. Placing additional Actors with "Is Spatially Loaded" enabled in the level ...
ChaosCacheManager is not reproducing Collision Events the second time you Record and Play
UE - Runtime - Simulation - Mar 28, 2025ChaosCacheManager (CCM) is not reproducing Collision events the second time (and onwards) we record a Geometry Collection (GC) breaking session. Particles set to track Collision Events correctly fol ...
Sequence with Override Instance Data enabled and a SubShot will accumulate the TransformOrigin Location wrongly and overshoot the expected end position
zComponent - Archive - Mar 28, 2025A Sequence with Override Instance Data enabled and a SubShot will accumulate the TransformOrigin Location wrongly and overshoot the expected end position. The licensee has encountered a particular s ...
Connecting a Client to a Server in PIE with Auto Connect to Server disabled will crash the editor
UE - Networking - Feb 22, 2016Connecting a Client to a Server in PIE with Auto Connect to Server disabled will crash the editor. EDIT: simple test project attached. Make sure Auto Connect to Server is disabled, and PIE with 2 p ...
HZB Setup Mips taking considerable time in GPU Visualizer
UE - Graphics Features - Jul 19, 2016HZB Setup Mips in the GPU Visualizer seems to be taking considerable ms in 4.12 and 4.13 compared to 4.11.2. This seems to mostly affect editor/PIE GPU Visualization but looks like it should when ...
Substrate: FPrimitiveViewRelevance::operator|= bitwise-ORs SubstrateUintPerPixel, inflating the per-pixel byte count and asserting under the blendable GBuffer
UE - Rendering - Features - Shading Models - Oct 6, 2026A crash can occur due to this check in Substrate.cpp when a material with 2 units and a material with 5 (20 bpp) uints are combined triggering :check(CurrentMaxBytesPerPixel <= PlatformSettingsBytes ...
Blueprint Structure breaks when the Editor is closed and re-opened if the struct contains variables that are a Class Reference and a Soft Object Reference to a Blueprint
UE - Gameplay - Blueprint - Nov 8, 2018A struct containing variables that are a Class Reference and Soft Object Reference to a Blueprint no longer works after the project is closed and re-opened in the Editor. If a variable of the struct ...
The Find Node Can Crash on Compile After a Blueprint Compile Error
UE - Gameplay - Nov 21, 2019The "Find" node can cause a crash if the a map with a struct value changes type while connected, is disconnected and reconnected. Compilation fails and crashes the engine. Found in 4.23.1 CL#963142 ...