Improving QGIS source code efficiency?

Question

I have noticed in the QGIS source code that the map layers gets added in two different places, in the Canvas and in the registry as follow:

    QgsMapLayerRegistry::instance()->addMapLayers(theMapLayers, TRUE);

    //! Create the Map Canvas
    m_pMapCanvas = new QgsMapCanvas(0, 0);
    // Set the Map Canvas Layer Set
    m_pMapCanvas->setLayerSet(myRList);

It seems like two separate copies of the map layers is being added to two different places, is there is away to make this more efficient?

Answer 1

There's no inefficiency here. They are only c++ pointers to the same layer instance -- it's not two instances in separate memory of the same map layer.