void WriteAttributeGetIndexHLSL ( const [FNiagaraDataInterfaceRWAttributeHelper](API\Plugins\Niagara\FNiagaraDataInterfaceRWAttribute-) & AttributeHelper, const [FNiagaraDataInterfaceGPUParamInfo](API\Plugins\NiagaraShader\FNiagaraDataInterfaceGPUParamInf-) & ParamInfo, const [FNiagaraDataInterfaceGeneratedFunction](API\Plugins\NiagaraShader\FNiagaraDataInterfaceGeneratedFu-) & FunctionInfo, int FunctionInstanceIndex, int32 InNumChannels, [FString](API\Runtime\Core\Containers\FString) & OutHLSL )