virtual void setFrom ( const [Reader](API\Plugins\RigLogicLib\dna\Reader) * source, [DataLayer](API\Plugins\RigLogicLib\dna\dna__DataLayer) layer, [UnknownLayerPolicy](API\Plugins\RigLogicLib\dna\dna__UnknownLayerPolicy) policy, [MemoryResource](API\Plugins\RigLogicLib\pma\MemoryResource) * memRes )