Unreal Engine Issues
Unreal Engine Issues
Ensure triggered in FBoundsCacheElement::GetValue when adding ISM instances in Construction Script
UE - AI - Oct 8, 2025An ensure is triggered in FBoundsCacheElement::GetValue when adding instances to an InstancedStaticMeshComponent inside a Blueprint’s Construction Script. This occurs when the ISM component is navig ...
Section::TrimSection resulting in bad key values at start and end of trim range
UE - Anim - Sequencer - Dec 17, 2025The trim process inserts keys at the start or end of the range depending if you specify Trim Left or Right, I'm finding that Trim right is inserting a key at the end of the section that is incorrect ...
Substrate Single Layer Water material fails to compile in blendable Gbuffer mode when using the Single Layer Water BSDF node
UE - Graphics Tools - Terrain - Water - Jun 16, 2026When using Substrate in Blendable GBuffer mode, a material with the single layer water BSDF node produces a shader compiler error : MaterialEditorStats: Error: [SM6] Shader debug info dumped to: "\ ...
VSCode finds intellisense errors in Project source files: cannot open source file "UBT_COMPILED_PLATFORM/UBT_COMPILED_PLATFORMPlatformCompilerPreSetup.h"
UE - Foundation - Cpp Tools - Jan 28, 2020VSCode finds intellisense errors in Project source files: cannot open source file "UBT_COMPILED_PLATFORM/UBT_COMPILED_PLATFORMPlatformCompilerPreSetup.h" Similar to [Link Removed], but that was onl ...
Incorrect volume bounds check in FTranslucentLightInjectionCollector::AddLightForInjection
UE - Graphics Features - Apr 8, 2025The 'VolumeBounds' array in FTranslucentLightInjectionCollector::AddLightForInjection is accessed as a pointer instead of with 'VolumeCascadeIndex' and thus fails bounds checks for the outer volume. ...
[CrashReport] Mac/Metal crash - Assertion failed: (PixelShader->Bindings.InOutMask
UE - Graphics Features - Nov 10, 2017This is a low frequency but trending crash coming out of 4.18. User DescriptionsAttempting to open a copied/converted from 4.16.3 project on 4.18 preview 4. Problem arose after preview 3. Was able ...
Runtime Virtual Texture (RVT) baked mips using Streaming Virtual Texture (SVT) only bakes the base colour
UE - Graphics Features - Sep 13, 2024Using Streaming Virtual Textures for the lower mips of an RVT using Base Color, Roughness, Normal seemingly leads to both roughness and normal being sampled as 0. This causes a significant shading a ...
[CrashReport] Tutorial crash UObject::execLetValueOnPersistentFrame()
UE - Gameplay - Blueprint - Jul 7, 2017This is another Tutorial crash that shares a similar callstack with [Link Removed] and [Link Removed], but those specific repro steps have been fixed while this one is still occurring in 4.16.2. On ...
Division by zero causing NaN/Inf on USkeletalMeshComponent::UpdateRigidBodyScaling() when setting scale to zero and back
UE - Runtime - Simulation - Feb 11, 2026Up to UE 5.5, skeletal mesh physics did not get updated when the component's scale changed. This was improved on January 2025 with CL 39190335, which addressed [Link Removed] ...
Compiling a blueprint with SetCollisionResponseToChannel Causes Crash
UE - Gameplay - Dec 5, 2016When using a blueprint with a destructible component, you can call the SetCollisionResponseToChannel node of that component in the construction script. As a result the engine will crash when attempt ...