Adding an instance static mesh component to a class causes the editor to crash when an instance is added to a blueprint of the class.
Regression:
Yes - this behavior does not occur on 4.16.3 (CL 3561208)
UPROPERTY(EditAnywhere, BlueprintReadOnly)
class UInstancedStaticMeshComponent* ModularMeshComponent;
#include "Runtime/Engine/Classes/Components/InstancedStaticMeshComponent.h"
ModularMeshComponent = CreateDefaultSubobject<UInstancedStaticMeshComponent>(TEXT("ModularMesh"));
Result:
Editor crashes with provided callstack
Expected:
The set mesh is added to the component for each instance in the array
LoginId:7156c35640f86204e61b8383f45dee17 EpicAccountId:c807849e05a0413d99e379f2802cae9c Assertion failed: Stream.VertexBuffer->IsInitialized() [File:D:\Build\++UE4+Release-4.17+Compile\Sync\Engine\Source\Runtime\ShaderCore\Private\VertexFactory.cpp] [Line: 184] Vertex buffer was not initialized! Stream 3, Stride 48, Name Static-mesh instances UE4Editor_Core!FDebug::AssertFailed() [d:\build\++ue4+release-4.17+compile\sync\engine\source\runtime\core\private\misc\assertionmacros.cpp:349] UE4Editor_ShaderCore!FVertexFactory::Set() [d:\build\++ue4+release-4.17+compile\sync\engine\source\runtime\shadercore\private\vertexfactory.cpp:184] UE4Editor_Renderer!FMeshDrawingPolicy::SetSharedState() [d:\build\++ue4+release-4.17+compile\sync\engine\source\runtime\renderer\private\drawingpolicy.cpp:198] UE4Editor_Renderer!FDepthDrawingPolicy::SetSharedState() [d:\build\++ue4+release-4.17+compile\sync\engine\source\runtime\renderer\private\depthrendering.cpp:421] UE4Editor_Renderer!FDepthDrawingPolicyFactory::DrawMesh() [d:\build\++ue4+release-4.17+compile\sync\engine\source\runtime\renderer\private\depthrendering.cpp:743] UE4Editor_Renderer!FDeferredShadingSceneRenderer::RenderPrePassViewDynamic() [d:\build\++ue4+release-4.17+compile\sync\engine\source\runtime\renderer\private\depthrendering.cpp:848] UE4Editor_Renderer!FDeferredShadingSceneRenderer::RenderPrePassView() [d:\build\++ue4+release-4.17+compile\sync\engine\source\runtime\renderer\private\depthrendering.cpp:980] UE4Editor_Renderer!FDeferredShadingSceneRenderer::RenderPrePass() [d:\build\++ue4+release-4.17+compile\sync\engine\source\runtime\renderer\private\depthrendering.cpp:1289] UE4Editor_Renderer!FDeferredShadingSceneRenderer::Render() [d:\build\++ue4+release-4.17+compile\sync\engine\source\runtime\renderer\private\deferredshadingrenderer.cpp:759] UE4Editor_Renderer!RenderViewFamily_RenderThread() [d:\build\++ue4+release-4.17+compile\sync\engine\source\runtime\renderer\private\scenerendering.cpp:1849] UE4Editor_Renderer!TGraphTask<`FRendererModule::BeginRenderingViewFamily'::`26'::EURCMacro_FDrawSceneCommand>::ExecuteTask() [d:\build\++ue4+release-4.17+compile\sync\engine\source\runtime\core\public\async\taskgraphinterfaces.h:784] UE4Editor_Core!FNamedTaskThread::ProcessTasksNamedThread() [d:\build\++ue4+release-4.17+compile\sync\engine\source\runtime\core\private\async\taskgraph.cpp:650] UE4Editor_Core!FNamedTaskThread::ProcessTasksUntilQuit() [d:\build\++ue4+release-4.17+compile\sync\engine\source\runtime\core\private\async\taskgraph.cpp:559] UE4Editor_RenderCore!RenderingThreadMain() [d:\build\++ue4+release-4.17+compile\sync\engine\source\runtime\rendercore\private\renderingthread.cpp:325] UE4Editor_RenderCore!FRenderingThread::Run() [d:\build\++ue4+release-4.17+compile\sync\engine\source\runtime\rendercore\private\renderingthread.cpp:459] UE4Editor_Core!FRunnableThreadWin::Run() [d:\build\++ue4+release-4.17+compile\sync\engine\source\runtime\core\private\windows\windowsrunnablethread.cpp:76]
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