odd behaviour with LODNode and geoms in an Actor

Scripting Issues
1

I am using the LODNode to switch between different geoms in my Actor, but the problem I am running into is that the Actor stops updating its animation when the high LOD is not visible, and even then it looks like it is animating at about 5 frames per second. I found if I attach a regular model onto a control joint then the Actor updates properly, though this is a poor workaround since it unnecessarily increases the number of geoms rendered.
Here is a paraphrasing of my code:

self.model = Actor()
self.model.loadModel('/path/to/model')
self.model.loadAnims(anims_dict)
lod_high_geo = self.model.find('**/')
lod_med_geo = self.model.find('**/lod_med')
lod_low_geo = self.model.find('**/lod_low')

lod = LODNode('LOD')
lod_np = NodePath(lod)
lod.addSwitch(25.0, 0.0)
lod_high_geo.reparentTo(lod_np)
lod.addSwitch(50.0, 25.0)
lod_med_geo.reparentTo(lod_np)
lod.addSwitch(1000000.0, 50.0)
lod_low_geo.reparentTo(lod_np)
lod_np.reparentTo(self.model)
self.model.reparentTo(render)

joint = model.exposeJoint(None, 'modelRoot', 'r_hand')
cube = loader.loadModel('cube')
cube.setScale(0.000001)
cube.reparentTo(joint)

My guess is that an optimization somewhere is saying hey you reparented all of the geoms out of the Actor, so it doesn’t need to be updated anymore. How can I get the Actor to update properly in a more friendly manner?

I am aware of the LOD functions of Actor but would prefer to use the much simpler LODNode interface.

2

Eeek, found the fix. If you parent the LODNode under the “model root” instead of the Actor NodePath it will update just fine.
Here is the parenting method that worked:

self.model = Actor()
self.model.loadModel('/path/to/model')
self.model.loadAnims(anims_dict)
lod_high_geo = self.model.find('**/')
modelroot = lod_high_geo.getParent()
lod_med_geo = self.model.find('**/lod_med')
lod_low_geo = self.model.find('**/lod_low')

lod = LODNode('LOD')
lod_np = NodePath(lod)
lod.addSwitch(25.0, 0.0)
lod_high_geo.reparentTo(lod_np)
lod.addSwitch(50.0, 25.0)
lod_med_geo.reparentTo(lod_np)
lod.addSwitch(1000000.0, 50.0)
lod_low_geo.reparentTo(lod_np)
lod_np.reparentTo(modelroot)
self.model.reparentTo(render)
3

It is true that mucking about in the nodes within an Actor can have unexpected consequences. To assist with constructing a multiple-LOD character, the Actor class has methods like setLODNode() and addLOD() that handle this sort of task automatically.

David