C++ UMaterial::GetAllExpressionsInMaterialAndFunctionsOfType方法代码示例

void UMaterialParameterCollection::PostEditChangeProperty(FPropertyChangedEvent& PropertyChangedEvent)
{
	// If the array counts have changed, an element has been added or removed, and we need to update the uniform buffer layout,
	// Which also requires recompiling any referencing materials
	if (ScalarParameters.Num() != PreviousScalarParameters.Num()
		|| VectorParameters.Num() != PreviousVectorParameters.Num())
	{
		// Limit the count of parameters to fit within uniform buffer limits
		const uint32 MaxScalarParameters = 1024;

		if (ScalarParameters.Num() > MaxScalarParameters)
		{
			ScalarParameters.RemoveAt(MaxScalarParameters, ScalarParameters.Num() - MaxScalarParameters);
		}

		const uint32 MaxVectorParameters = 1024;

		if (VectorParameters.Num() > MaxVectorParameters)
		{
			VectorParameters.RemoveAt(MaxVectorParameters, VectorParameters.Num() - MaxVectorParameters);
		}

		// Generate a new Id so that unloaded materials that reference this collection will update correctly on load
		StateId = FGuid::NewGuid();

		// Update the uniform buffer layout
		CreateBufferStruct();

		// Recreate each instance of this collection
		for (TObjectIterator<UWorld> It; It; ++It)
		{
			UWorld* CurrentWorld = *It;
			CurrentWorld->AddParameterCollectionInstance(this, false);
		}

		// Build set of changed parameter names
		TSet<FName> ParameterNames;
		for (const FCollectionVectorParameter& Param : PreviousVectorParameters)
		{
			ParameterNames.Add(Param.ParameterName);
		}

		for (const FCollectionScalarParameter& Param : PreviousScalarParameters)
		{
			ParameterNames.Add(Param.ParameterName);
		}

		for (const FCollectionVectorParameter& Param : VectorParameters)
		{
			ParameterNames.Remove(Param.ParameterName);
		}

		for (const FCollectionScalarParameter& Param : ScalarParameters)
		{
			ParameterNames.Remove(Param.ParameterName);
		}

		// Create a material update context so we can safely update materials using this parameter collection.
		{
			FMaterialUpdateContext UpdateContext;

			// Go through all materials in memory and recompile them if they use this material parameter collection
			for (TObjectIterator<UMaterial> It; It; ++It)
			{
				UMaterial* CurrentMaterial = *It;

				bool bRecompile = false;

				// Preview materials often use expressions for rendering that are not in their Expressions array, 
				// And therefore their MaterialParameterCollectionInfos are not up to date.
				if (CurrentMaterial->bIsPreviewMaterial)
				{
					bRecompile = true;
				}
				else
				{
					for (int32 FunctionIndex = 0; FunctionIndex < CurrentMaterial->MaterialParameterCollectionInfos.Num() && !bRecompile; FunctionIndex++)
					{
						if (CurrentMaterial->MaterialParameterCollectionInfos[FunctionIndex].ParameterCollection == this)
						{
							TArray<UMaterialExpressionCollectionParameter*> CollectionParameters;
							CurrentMaterial->GetAllExpressionsInMaterialAndFunctionsOfType(CollectionParameters);
							for (UMaterialExpressionCollectionParameter* CollectionParameter : CollectionParameters)
							{
								if (ParameterNames.Contains(CollectionParameter->ParameterName))
								{
									bRecompile = true;
									break;
								}
							}
						}
					}
				}

				if (bRecompile)
				{
					UpdateContext.AddMaterial(CurrentMaterial);

					// Propagate the change to this material
					CurrentMaterial->PreEditChange(NULL);
//.........这里部分代码省略.........