Maya callback when node added to render layer?

Tools Maya
1

I have been looking through the OpenMaya events and MEL and python scriptJobs and have yet to find any effective way of registering a callback when a node is added to a render layer (in Maya 2012). The builtin MEL proc is renderLayerEditorAddObjects and is located in layerEditor.mel but I do not want to modify any of the builtin Maya MEL code.

Is there another event or attribute I could attempt to create an event listener for? The renderLayerEditorAddObjects does an eval on editRenderLayerMembers to actually add the members to the layer. My current approach would be to add a scriptJob to the renderLayerManagerChange event and keep state information on every render layer to see what changes, but this will induce a lot of wasted processing (since it is called everytime a render layer is selected).

Any suggestions would be appreciated.

2

Not what you wanted, but you could modify a copy of layerEditor.mel as desired, and load it through userSetup on startup.