The IFPLayerManager class is also an interface class that manages scene layers in 3ds Max. This class however is a function published interface, and thus is quite different from the previously discussed layer manager. This class is the C++ interfaces to the MAXScript LayerManager class. This class has a useful method fro returning a layer by integer index. Thus you can iterate over scene layers without knowing the names of the layers. To get a pointer to this object you call the GetCOREInterface() function.

IFPLayerManager* layer_manager = static_cast< IFPLayerManager*> GetCOREInterface( LAYERMANAGER_INTERFACE);

The LAYERMANAGER_INTERFACE identifies the IFPLayerManager interface. With the resulting pointer you can get a scene layer by integer index.

ILayerProperties* hLayer = layer_manager->getLayer(i);

This IFPLayerManager::getLayer() method returns a ILayerProperties pointer which has much less functionality than ILayer.

To get an ILayer pointer you can get a pointer to any object on that layer, and extract the ILayer pointer from it.