void Setup ( const [FNiagaraVariableBase](API\Plugins\Niagara\FNiagaraVariableBase) & InRootVar, const [FNiagaraVariable](API\Plugins\Niagara\FNiagaraVariable) & InDefaultValue, [ENiagaraRendererSourceDataMode](API\Plugins\Niagara\ENiagaraRendererSourceDataMode) InSourceMode )