Unreal Engine Issues
Unreal Engine Issues
UBT crashes when doing an incremental build
UE - Foundation - Cpp Tools - UnrealBuildTool - Aug 9, 2017There is a consistent crash when incrementally compiling headers containing generated code. The code for launching UHT accesses a property which is null when compiling with the UBT makefile. ...
VisualizeTexture with the BMP flag causes a crash when any mip over mip0 is requested
UE - Rendering Architecture - Dec 18, 2024When a mip level higher than 0 is requested in VisualizeTexture, the engine will crash. The root cause appears to be VisualizeTexture.cpp:924, on which an incorrect mip level is used to read a non-m ...
Instigator is no longer automatically set when spawning actors from blueprint
UE - Gameplay - Blueprint - Aug 20, 2024Actors that are spawned from blueprints will no longer have their instigator automatically set to the instigator that spawned them. This is a regression in 5.5, because in 5.4 and earlier a null Ins ...
BlendListByEnum assumes that enum values are sequential
UE - Anim - Runtime - Anim Blueprints - Aug 26, 2024FAnimNode_BlendListByEnum assumes that values within a custom enum type are sequential (ie. the index 0 = value 0, index 1 = value 1). But this is not true of all custom enum types, for example: U ...
Shortcut for Swing1Motion (2, and 3) do not change physics asset state dirty.
OLD - Anim - Sep 8, 2017Shortcut for Toggle Angular Limits 1, 2 and 3 for Physics assets do not change phys asset state as dirty. ...
Sphere Mask ArgInvHardness missing multiplication
UE - Rendering Architecture - Materials - Jun 27, 2025Hi Epic, In MaterialExpressions.cpp UMaterialExpressionSphereMask::Compile(), hardness is not calculated the same way in both <if> conditions. One is missing a multiplication by 0.01f. Specificall ...
Adding assets to a project on a drive that is full still creates the file at the desired location instead of in a temporary location and provides no information as to why the asset is failing to load, corrupting the asset
Tools - Oct 31, 2016Adding assets to a project on a drive that is full still creates the file at the desired location instead of in a temporary location and provides no information as to why the asset is failing to loa ...
Disabling 'Use Landscape Lightmap' option Skewing Procedural Foliage Instances
UE - LD & Modeling - Terrain - Landscape - Oct 24, 2016Disabling the 'Use Landscape Lightmap' when using procedural foliage, will skew the placed instanced meshes. Regression? Yes, this issue did not occur in the 4.13.1 release. ...
Fbx importer can import valid under 30Hz anim at 30Hz
Tools - Jul 17, 2017The samplerate of a track was compute with the following formula Equation 1: number of Key / animation Time This formula work only if we have animation keys that are time equidistant. example of ...
Scalar Parameter versus Constant placed in Alpha of LERP produces inconsistent results in Blendable
UE - Graphics Features - Jun 8, 2015When placing a Scalar Parameter into the Alpha position of a LERP you will not get the same results as placing a Constant Value when used in a Post Process Material. Constant Value of 0: [Image Rem ...