Unreal Engine Issues and Bug Tracker (UE-45739)

Description

This is one of the top Mac crashes occurring in 4.16. Caused by adding Auto Convex Collision to a mesh converted from a brush. Does not occur on Windows.

User Descriptions

I was trying to add a convex collision component to a box brush that i converted into a static mesh for faster rendering...When I tried applying 6 to the almost .9 accuracy on the collision creation, the program crashed again, 2 times in a row over the same collision creating issue.
I would like to ultimately know how to add a proper blocking volume on imported meshes and converted brushes into static meshes that have very good bocking volumes...
I also would like to be ab

Steps to Reproduce

Open UE4 Editor (Any Project) on Mac
Open Modes->Geometry
Add Box brush to the viewport
In Details Panel, convert brush to static mesh
Open mesh in Mesh Editor
Collision->Auto Convex Collision
Click Apply under Convex Decomposition

Result:
Editor immediately closes

Expected:
Convex collision settings are updated and applied

Callstack

UE4Editor-UnrealEd.dylib!void VHACD::VHACD::AlignMesh<float>()
UE4Editor-UnrealEd.dylib!bool VHACD::VHACD::ComputeACD<float>()
UE4Editor-UnrealEd.dylib!DecomposeMeshToHulls()
UE4Editor-StaticMeshEditor.dylib!FStaticMeshEditor::DoDecomp()
UE4Editor-StaticMeshEditor.dylib!SConvexDecomposition::OnApplyDecomp()
UE4Editor-StaticMeshEditor.dylib!TBaseSPMethodDelegateInstance<false, SConvexDecomposition, (ESPMode)0, FReply ()>::Execute()
UE4Editor-Slate.dylib!SButton::OnMouseButtonUp()
UE4Editor-Slate.dylib!FSlateApplication::RoutePointerUpEvent()
UE4Editor-Slate.dylib!FSlateApplication::ProcessMouseButtonUpEvent()
UE4Editor-Slate.dylib!FSlateApplication::OnMouseUp()
UE4Editor-Core.dylib!FMacApplication::ProcessEvent()
UE4Editor-Core.dylib!FMacApplication::ProcessDeferredEvents()
UE4Editor-Slate.dylib!FSlateApplication::TickPlatform()
UE4Editor-Slate.dylib!FSlateApplication::Tick()
UE4Editor!FEngineLoop::Tick()
UE4Editor!GuardedMain()
UE4Editor!<Unknown>
UE4Editor-Core.dylib!<Unknown>
Foundation!Unknown()
libsystem_pthread.dylib!<Unknown>
libsystem_pthread.dylib!<Unknown>
libsystem_pthread.dylib!<Unknown>

Have Comments or More Details?

There's no existing public thread on this issue, so head over to Questions & Answers just mention UE-45739 in the post.

0	Login to Vote

Fixed

Component	UE - Platform - Apple
Affects Versions	4.16
Target Fix	4.16.2, 4.17

Fix Commit	3499527
Main Commit	3617655
Release Commit	3536044

Created	Jun 6, 2017
Resolved	Jun 19, 2017
Updated	Apr 27, 2018

UE-45739

Crash on Mac when adding Convex Collision to a mesh converted from a brush

Crash on Mac when adding Convex Collision to a mesh converted from a brush

Have Comments or More Details?