node buddy #houdini #python

node_buddy.py

"""
Keep a node close to its buddy whenever the buddy is moved
  - uses event call back which is only persisstant in session :(

"""

# create geo
geo = hou.node('obj').createNode('geo')

# create two nodes
mat = geo.createNode('material')
matnet = geo.createNode('matnet', 'materials_buddy')

# define the method the callback will call
def node_moved(event_type, **kwargs):
    matnet.setPosition(kwargs['node'].position() + hou.Vector2(2, 0))

#######

# this isnt persistant so we need to do something to save it in the hip

# save this buddy to the node in its userdata
mat.setUserData('bee_buddy', matnet.path())

# when scene is loaded in 456.py

# check nodes for buddys
for node in hou.node('obj').allSubChildren():
    buddy = node.userDataDict().get('bee_buddy', False)

    if not buddy:
        continue

    print('{} - {}'.format(node.name(), buddy))
    # add event, but need to customise the function! hmmm
    node.addEventCallback((hou.nodeEventType.PositionChanged,), node_moved)
    
    
# add event callback when the position of the mat node has changed
mat.addEventCallback((hou.nodeEventType.PositionChanged,), node_moved)