bAutoGenerateCollision
bAutoGenerateCollision
#Overview
name: bAutoGenerateCollision
The value of this variable can be defined or overridden in .ini config files. 1 .ini config file referencing this setting variable.
It is referenced in 19 C++ source files.
#Summary
#Usage in the C++ source code
The purpose of bAutoGenerateCollision is to control automatic collision generation for static meshes during import in Unreal Engine 5. This setting is primarily used in the context of importing 3D models, particularly static meshes, into the engine.
The bAutoGenerateCollision variable is mainly used by the Unreal Engine’s FBX import system and the Interchange Editor plugin. It’s part of the static mesh import data and is utilized in the following subsystems:
- FBX Import System
- Interchange Editor Plugin
- Static Mesh Import/Reimport Process
The value of this variable is typically set in the following ways:
- Through the UFbxStaticMeshImportData class constructor, where it’s initialized to true by default.
- Via the Unreal Editor’s import settings UI for static meshes.
- Programmatically when configuring import options for static meshes.
This variable interacts with other import settings, particularly:
- bCustomizedCollision: If a mesh has customized collision, bAutoGenerateCollision is forced to false during reimport.
- Other static mesh import options like bGenerateLightmapUVs, bOneConvexHullPerUCX, etc.
Developers should be aware of the following when using this variable:
- Setting this to true will automatically generate collision for imported static meshes, which might not always be desirable for performance reasons or if custom collision is needed.
- If a mesh already has customized collision, this setting will be ignored during reimport to preserve the custom collision.
Best practices when using this variable include:
- Consider performance implications of auto-generating collision for all imported meshes.
- For complex or performance-critical meshes, consider creating custom collision instead of relying on auto-generation.
- Be aware that this setting may be overridden in certain scenarios, such as when reimporting meshes with custom collision.
- Use this in conjunction with other import settings to achieve the desired balance between automation and control over the imported assets.
#Setting Variables
#References In INI files
Location: <Workspace>/Engine/Config/BaseEditorPerProjectUserSettings.ini:662, section: [/Script/UnrealEd.FbxStaticMeshImportData]
- INI Section:
/Script/UnrealEd.FbxStaticMeshImportData - Raw value:
True - Is Array:
False
#References in C++ code
#Callsites
This variable is referenced in the following C++ source code:
#Loc: <Workspace>/Engine/Plugins/Interchange/Editor/Source/InterchangeEditor/Private/InterchangeFbxAssetImportDataConverter.cpp:148
Scope (from outer to inner):
file
namespace UE::Interchange::Private
function void FillInterchangeGenericAssetsPipelineFromFbxStaticMeshImportData
Source code excerpt:
}
GenericAssetPipeline->MeshPipeline->bImportCollision = StaticMeshImportData->bAutoGenerateCollision;
GenericAssetPipeline->MeshPipeline->bBuildNanite = StaticMeshImportData->bBuildNanite;
GenericAssetPipeline->MeshPipeline->bBuildReversedIndexBuffer = StaticMeshImportData->bBuildReversedIndexBuffer;
GenericAssetPipeline->MeshPipeline->bCombineStaticMeshes = StaticMeshImportData->bCombineMeshes;
GenericAssetPipeline->MeshPipeline->bGenerateLightmapUVs = StaticMeshImportData->bGenerateLightmapUVs;
GenericAssetPipeline->MeshPipeline->bOneConvexHullPerUCX = StaticMeshImportData->bOneConvexHullPerUCX;
GenericAssetPipeline->CommonMeshesProperties->bRemoveDegenerates = StaticMeshImportData->bRemoveDegenerates;
#Loc: <Workspace>/Engine/Plugins/Interchange/Editor/Source/InterchangeEditor/Private/InterchangeFbxAssetImportDataConverter.cpp:313
Scope (from outer to inner):
file
namespace UE::Interchange::Private
function UAssetImportData* ConvertToLegacyFbx
Source code excerpt:
FillFbxMeshImportData(GenericAssetPipeline, DestinationStaticMeshImportData);
DestinationStaticMeshImportData->bAutoGenerateCollision = GenericAssetPipeline->MeshPipeline->bImportCollision;
DestinationStaticMeshImportData->bBuildNanite = GenericAssetPipeline->MeshPipeline->bBuildNanite;
DestinationStaticMeshImportData->bBuildReversedIndexBuffer = GenericAssetPipeline->MeshPipeline->bBuildReversedIndexBuffer;
DestinationStaticMeshImportData->bCombineMeshes = GenericAssetPipeline->MeshPipeline->bCombineStaticMeshes;
DestinationStaticMeshImportData->bGenerateLightmapUVs = GenericAssetPipeline->MeshPipeline->bGenerateLightmapUVs;
DestinationStaticMeshImportData->bOneConvexHullPerUCX = GenericAssetPipeline->MeshPipeline->bOneConvexHullPerUCX;
DestinationStaticMeshImportData->bRemoveDegenerates = GenericAssetPipeline->CommonMeshesProperties->bRemoveDegenerates;
#Loc: <Workspace>/Engine/Plugins/Tests/EditorTests/Source/EditorTests/Private/UnrealEd/FbxAutomationTests.cpp:386
Scope (from outer to inner):
file
function BEGIN_FUNCTION_BUILD_OPTIMIZATION bool F
Source code excerpt:
ImportData->bGenerateLightmapUVs = TestPlan->ImportUI->StaticMeshImportData->bGenerateLightmapUVs;
ImportData->bOneConvexHullPerUCX = TestPlan->ImportUI->StaticMeshImportData->bOneConvexHullPerUCX;
ImportData->bAutoGenerateCollision = TestPlan->ImportUI->StaticMeshImportData->bAutoGenerateCollision;
//Copy UFbxMeshImportData
ImportData->bTransformVertexToAbsolute = TestPlan->ImportUI->StaticMeshImportData->bTransformVertexToAbsolute;
ImportData->bBakePivotInVertex = TestPlan->ImportUI->StaticMeshImportData->bBakePivotInVertex;
ImportData->bImportMeshLODs = TestPlan->ImportUI->StaticMeshImportData->bImportMeshLODs;
ImportData->NormalImportMethod = TestPlan->ImportUI->StaticMeshImportData->NormalImportMethod;
ImportData->NormalGenerationMethod = TestPlan->ImportUI->StaticMeshImportData->NormalGenerationMethod;
#Loc: <Workspace>/Engine/Plugins/Tests/EditorTests/Source/EditorTests/Private/UnrealEd/FbxAutomationTests.cpp:494
Scope (from outer to inner):
file
function BEGIN_FUNCTION_BUILD_OPTIMIZATION bool F
Source code excerpt:
ImportData->bGenerateLightmapUVs = TestPlan->ImportUI->StaticMeshImportData->bGenerateLightmapUVs;
ImportData->bOneConvexHullPerUCX = TestPlan->ImportUI->StaticMeshImportData->bOneConvexHullPerUCX;
ImportData->bAutoGenerateCollision = TestPlan->ImportUI->StaticMeshImportData->bAutoGenerateCollision;
//Copy UFbxMeshImportData
ImportData->bTransformVertexToAbsolute = TestPlan->ImportUI->StaticMeshImportData->bTransformVertexToAbsolute;
ImportData->bBakePivotInVertex = TestPlan->ImportUI->StaticMeshImportData->bBakePivotInVertex;
ImportData->bImportMeshLODs = TestPlan->ImportUI->StaticMeshImportData->bImportMeshLODs;
ImportData->NormalImportMethod = TestPlan->ImportUI->StaticMeshImportData->NormalImportMethod;
ImportData->NormalGenerationMethod = TestPlan->ImportUI->StaticMeshImportData->NormalGenerationMethod;
#Loc: <Workspace>/Engine/Source/Editor/UnrealEd/Classes/Factories/FbxSceneImportOptionsStaticMesh.h:55
Scope (from outer to inner):
file
class class UFbxSceneImportOptionsStaticMesh : public UObject
Source code excerpt:
/** If checked, collision will automatically be generated (ignored if custom collision is imported or used). */
UPROPERTY(EditAnywhere, config, Category = StaticMesh, DisplayName = "Generate Missing Collision")
uint32 bAutoGenerateCollision : 1;
/** Specify how vertex colors should be imported */
UPROPERTY(EditAnywhere, config, Category = StaticMesh)
EFbxSceneVertexColorImportOption VertexColorImportOption;
/** Specify override color in the case that VertexColorImportOption is set to Override */
#Loc: <Workspace>/Engine/Source/Editor/UnrealEd/Classes/Factories/FbxStaticMeshImportData.h:50
Scope (from outer to inner):
file
class class UFbxStaticMeshImportData : public UFbxMeshImportData
Source code excerpt:
/** If checked, collision will automatically be generated (ignored if custom collision is imported or used). */
UPROPERTY(EditAnywhere, BlueprintReadWrite, config, Category = Mesh, meta=(OBJRestrict="true", ImportType="StaticMesh", DisplayName="Generate Missing Collision"))
uint32 bAutoGenerateCollision : 1;
/** For static meshes, enabling this option will combine all meshes in the FBX into a single monolithic mesh in Unreal */
UPROPERTY(EditAnywhere, BlueprintReadWrite, AdvancedDisplay, config, Category = Mesh, meta = (ToolTip = "If enabled, combines all meshes into a single mesh", ImportType = "StaticMesh"))
uint32 bCombineMeshes : 1;
/**
#Loc: <Workspace>/Engine/Source/Editor/UnrealEd/Private/Factories/EditorFactories.cpp:6174
Scope (from outer to inner):
file
function EReimportResult::Type UReimportFbxStaticMeshFactory::Reimport
Source code excerpt:
}
//Force the bAutoGenerateCollision to false if the Mesh Customize collision is true
bool bOldAutoGenerateCollision = ReimportUI->StaticMeshImportData->bAutoGenerateCollision;
if (Mesh->bCustomizedCollision)
{
ReimportUI->StaticMeshImportData->bAutoGenerateCollision = false;
}
bool bImportOperationCanceled = false;
bool bForceImportType = true;
bool bShowOptionDialog = true;
bool bOutImportAll = false;
#Loc: <Workspace>/Engine/Source/Editor/UnrealEd/Private/Factories/EditorFactories.cpp:6190
Scope (from outer to inner):
file
function EReimportResult::Type UReimportFbxStaticMeshFactory::Reimport
Source code excerpt:
GetImportOptions( FFbxImporter, ReimportUI, bShowOptionDialog, bIsAutomated, Obj->GetPathName(), bOperationCanceled, bOutImportAll, bIsObjFormat, Filename, bForceImportType, FBXIT_StaticMesh);
//Put back the original bAutoGenerateCollision settings since the user cancel the re-import
check( ReimportUI->StaticMeshImportData != nullptr );
if ( bOperationCanceled && Mesh->bCustomizedCollision)
{
ReimportUI->StaticMeshImportData->bAutoGenerateCollision = bOldAutoGenerateCollision;
}
//Put back the original SM outer
if ( OriginalOuter)
{
ReimportUI->StaticMeshImportData->Rename(nullptr, OriginalOuter);
#Loc: <Workspace>/Engine/Source/Editor/UnrealEd/Private/Fbx/FbxMainImport.cpp:492
Scope (from outer to inner):
file
namespace UnFbx
function void ApplyImportUIToImportOptions
Source code excerpt:
InOutImportOptions.bGenerateLightmapUVs = ImportUI->StaticMeshImportData->bGenerateLightmapUVs;
InOutImportOptions.bOneConvexHullPerUCX = ImportUI->StaticMeshImportData->bOneConvexHullPerUCX;
InOutImportOptions.bAutoGenerateCollision = ImportUI->StaticMeshImportData->bAutoGenerateCollision;
InOutImportOptions.StaticMeshLODGroup = ImportUI->StaticMeshImportData->StaticMeshLODGroup;
}
// animation unshared options
{
#Loc: <Workspace>/Engine/Source/Editor/UnrealEd/Private/Fbx/FbxMainImport.cpp:1741
Scope (from outer to inner):
file
lambda-function
Source code excerpt:
auto AddMeshAnalytic = [&Attribs, &CaptureImportOptions]()
{
Attribs.Add(FAnalyticsEventAttribute(TEXT("MeshOpt AutoGenerateCollision"), CaptureImportOptions->bAutoGenerateCollision));
Attribs.Add(FAnalyticsEventAttribute(TEXT("MeshOpt CombineToSingle"), CaptureImportOptions->bCombineToSingle));
Attribs.Add(FAnalyticsEventAttribute(TEXT("MeshOpt BakePivotInVertex"), CaptureImportOptions->bBakePivotInVertex));
Attribs.Add(FAnalyticsEventAttribute(TEXT("MeshOpt TransformVertexToAbsolute"), CaptureImportOptions->bTransformVertexToAbsolute));
Attribs.Add(FAnalyticsEventAttribute(TEXT("MeshOpt ImportRigidMesh"), CaptureImportOptions->bImportRigidMesh));
Attribs.Add(FAnalyticsEventAttribute(TEXT("MeshOpt NormalGenerationMethod"), FBXNormalGenerationMethodEnum->GetNameStringByValue(CaptureImportOptions->NormalGenerationMethod)));
Attribs.Add(FAnalyticsEventAttribute(TEXT("MeshOpt NormalImportMethod"), FBXNormalImportMethodEnum->GetNameStringByValue(CaptureImportOptions->NormalImportMethod)));
#Loc: <Workspace>/Engine/Source/Editor/UnrealEd/Private/Fbx/FbxSceneImportData.cpp:105
Scope (from outer to inner):
file
function UnFbx::FBXImportOptions *JSONToFbxOption
Source code excerpt:
OptionObj->TryGetBoolField(TEXT("bGenerateLightmapUVs"), Option->bGenerateLightmapUVs);
OptionObj->TryGetBoolField(TEXT("bOneConvexHullPerUCX"), Option->bOneConvexHullPerUCX);
OptionObj->TryGetBoolField(TEXT("bAutoGenerateCollision"), Option->bAutoGenerateCollision);
FString LODGroup;
if (OptionObj->TryGetStringField(TEXT("StaticMeshLODGroup"), LODGroup))
{
Option->StaticMeshLODGroup = FName(*LODGroup);
}
OptionObj->TryGetBoolField(TEXT("bImportStaticMeshLODs"), Option->bImportStaticMeshLODs);
#Loc: <Workspace>/Engine/Source/Editor/UnrealEd/Private/Fbx/FbxSceneImportData.cpp:200
Scope (from outer to inner):
file
function FString FbxOptionToJSON
Source code excerpt:
Option->bGenerateLightmapUVs ? 1 : 0,
Option->bOneConvexHullPerUCX ? 1 : 0,
Option->bAutoGenerateCollision ? 1 : 0,
*(Option->StaticMeshLODGroup.ToString()),
Option->bImportStaticMeshLODs ? 1 : 0
);
JsonString += FString::Printf(TEXT("\"bUpdateSkeletonReferencePose\" : \"%d\", \"bUseT0AsRefPose\" : \"%d\", \"bPreserveSmoothingGroups\" : \"%d\", \"bKeepSectionsSeparate\" : \"%d\", \"bImportMeshesInBoneHierarchy\" : \"%d\", \"bImportMorphTargets\" : \"%d\", , \"bImportVertexAttributes\" : \"%d\", \"OverlappingThresholds\" : {\"ThresholdPosition\" : \"%f\", \"ThresholdTangentNormal\" : \"%f\", \"ThresholdUV\" : \"%f\", \"MorphThresholdPosition\" : \"%f\"},"),
Option->bUpdateSkeletonReferencePose ? 1 : 0,
#Loc: <Workspace>/Engine/Source/Editor/UnrealEd/Private/Fbx/FbxSceneImportOptionsStaticMesh.cpp:16
Scope (from outer to inner):
file
function UFbxSceneImportOptionsStaticMesh::UFbxSceneImportOptionsStaticMesh
Source code excerpt:
: Super(ObjectInitializer)
, StaticMeshLODGroup(NAME_None)
, bAutoGenerateCollision(true)
, bRemoveDegenerates(true)
, bBuildReversedIndexBuffer(true)
, bGenerateLightmapUVs(true)
, bOneConvexHullPerUCX(true)
{
VertexOverrideColor = FColor(255, 255, 255, 255);
#Loc: <Workspace>/Engine/Source/Editor/UnrealEd/Private/Fbx/FbxSceneImportOptionsStaticMesh.cpp:31
Scope (from outer to inner):
file
function void UFbxSceneImportOptionsStaticMesh::FillStaticMeshInmportData
Source code excerpt:
check(StaticMeshImportData != nullptr);
check(SceneImportOptions != nullptr);
StaticMeshImportData->bAutoGenerateCollision = bAutoGenerateCollision;
StaticMeshImportData->bBuildReversedIndexBuffer = bBuildReversedIndexBuffer;
StaticMeshImportData->bGenerateLightmapUVs = bGenerateLightmapUVs;
StaticMeshImportData->bOneConvexHullPerUCX = bOneConvexHullPerUCX;
StaticMeshImportData->bRemoveDegenerates = bRemoveDegenerates;
StaticMeshImportData->StaticMeshLODGroup = StaticMeshLODGroup;
switch (VertexColorImportOption)
#Loc: <Workspace>/Engine/Source/Editor/UnrealEd/Private/Fbx/FbxStaticMeshImport.cpp:2423
Scope (from outer to inner):
file
function void UnFbx::FFbxImporter::PostImportStaticMesh
Source code excerpt:
//collision generation must be done after the build, this will ensure a valid BodySetup
if (StaticMesh->bCustomizedCollision == false && ImportOptions->bAutoGenerateCollision && StaticMesh->GetBodySetup() && LODIndex == 0)
{
FKAggregateGeom & AggGeom = StaticMesh->GetBodySetup()->AggGeom;
AggGeom.ConvexElems.Empty(1); //if no custom collision is setup we just regenerate collision when reimport
const int32 NumDirs = 18;
TArray<FVector> Dirs;
#Loc: <Workspace>/Engine/Source/Editor/UnrealEd/Private/Fbx/FbxStaticMeshImportData.cpp:12
Scope (from outer to inner):
file
function UFbxStaticMeshImportData::UFbxStaticMeshImportData
Source code excerpt:
bGenerateLightmapUVs = true;
bOneConvexHullPerUCX = true;
bAutoGenerateCollision = true;
bTransformVertexToAbsolute = true;
bBakePivotInVertex = false;
VertexOverrideColor = FColor(255, 255, 255, 255);
DistanceFieldResolutionScale = 1.0f;
}
#Loc: <Workspace>/Engine/Source/Editor/UnrealEd/Private/Fbx/SFbxSceneOptionWindow.cpp:1401
Scope (from outer to inner):
file
function void SFbxSceneOptionWindow::CopyStaticMeshOptionsToFbxOptions
Source code excerpt:
void SFbxSceneOptionWindow::CopyStaticMeshOptionsToFbxOptions(UnFbx::FBXImportOptions *ImportSettings, UFbxSceneImportOptionsStaticMesh* StaticMeshOptions)
{
ImportSettings->bAutoGenerateCollision = StaticMeshOptions->bAutoGenerateCollision;
ImportSettings->bBuildReversedIndexBuffer = StaticMeshOptions->bBuildReversedIndexBuffer;
ImportSettings->bGenerateLightmapUVs = StaticMeshOptions->bGenerateLightmapUVs;
ImportSettings->bOneConvexHullPerUCX = StaticMeshOptions->bOneConvexHullPerUCX;
ImportSettings->bRemoveDegenerates = StaticMeshOptions->bRemoveDegenerates;
ImportSettings->StaticMeshLODGroup = StaticMeshOptions->StaticMeshLODGroup;
switch (StaticMeshOptions->VertexColorImportOption)
#Loc: <Workspace>/Engine/Source/Editor/UnrealEd/Private/Fbx/SFbxSceneOptionWindow.cpp:1447
Scope (from outer to inner):
file
function void SFbxSceneOptionWindow::CopyFbxOptionsToStaticMeshOptions
Source code excerpt:
void SFbxSceneOptionWindow::CopyFbxOptionsToStaticMeshOptions(UnFbx::FBXImportOptions *ImportSettings, UFbxSceneImportOptionsStaticMesh* StaticMeshOptions)
{
StaticMeshOptions->bAutoGenerateCollision = ImportSettings->bAutoGenerateCollision;
StaticMeshOptions->bBuildReversedIndexBuffer = ImportSettings->bBuildReversedIndexBuffer;
StaticMeshOptions->bGenerateLightmapUVs = ImportSettings->bGenerateLightmapUVs;
StaticMeshOptions->bOneConvexHullPerUCX = ImportSettings->bOneConvexHullPerUCX;
StaticMeshOptions->bRemoveDegenerates = ImportSettings->bRemoveDegenerates;
StaticMeshOptions->StaticMeshLODGroup = ImportSettings->StaticMeshLODGroup;
switch (ImportSettings->VertexColorImportOption)
#Loc: <Workspace>/Engine/Source/Editor/UnrealEd/Public/FbxImporter.h:154
Scope (from outer to inner):
file
namespace UnFbx
Source code excerpt:
bool bGenerateLightmapUVs;
bool bOneConvexHullPerUCX;
bool bAutoGenerateCollision;
FName StaticMeshLODGroup;
bool bImportStaticMeshLODs;
bool bAutoComputeLodDistances;
TArray<float> LodDistances;
int32 MinimumLodNumber;
int32 LodNumber;