(LOCK ON) Camera Method?

I’m new at Panda3d, so i just wanted to ask . . .

lets say i wanted to implement a type of lock on type control in my game. ( Lock On Occurs when you click a model.) I want an effect of graphic to appear in the center of the selected model. I also want to ensure that when the main character moves . . he will still be seen, but the camera will remain pointing at the center of the selected model. Sort of like the lock on system of kingdom hearts. How should i go about this?

for the camera to follow a node, you can use camera.look_at(Node)

for the node center marker, there are many options to choose from.
I think using a card ( check the manual for CardMaker ) would be sufficient.