Pythonhoudini

From DreamsteepWiki

Notes from Keith

hou_examples

DOCS

http://www.sidefx.com/docs/houdini9.5/hom/hou/Node

Change a nodes name

nod.setName('mynoder')

ASCODE

hou.Node.asCode( hou.node("/obj/keiths_network"))

HOU module list all py modules in houdini

dir(hou)

KEYFRAMES (UNTESTED)

hou.Keyframe()
hou_keyframe.setTime(1.70833)
hou_keyframe.setValue(0)
hou_keyframe.setSlope(0)
hou_keyframe.setAccel(0.333333)
hou_keyframe.setExpression("bezier()", hou.exprLanguage.Hscript)
hou_keyed_parm.setKeyframe(hou_keyframe)

RUN AN HSCRIPT COMMAND

hou.hscript('opls')

DIR (NO PYTHON COM EXISTS FOR THIS)

hou.hscript('opls')

OPLAYOUT (NOT WORKING)

a.layoutChildren()

SET A TRANSLATION VALUE

b.parm('tx').set(3)

access a parameter (translation x in this example)

tx = g.parm('tx')
VALUE = tx.eval()

change a parameter

import hou
g = hou.node('/obj').createNode('geo')
tx = g.parm('tx')
tx.set(3.618)
print tx.eval()

NAVIGATING HOUDINI

hou.cd('/img')
hou.pwd()
hou.cd('..')

SHOW ORIGIN

a.showOrigin(True)

parenting (linking on obj level)

a = hou.node('/obj').createNode('geo')
b = hou.node('/obj').createNode('geo')
b.setInput(0,a)

LIST CHILDREN

for n in hou.node("/obj").children():
    print n.name()

make selectable

hou_node.setSelectableInViewport(True)

set visibility

 n.setDisplayFlag(True)
 n.setDisplayFlag(False)

clear the scene

hou.hipFile.clear()

add your own command folder to the PATH

import sys
sys.path.append('/path/to/hou_pyhon_scripts')

make a node type geo in /obj

g = hou.node('/obj').createNode('geo')

select a node

query selected

for n in hou.selectedNodes():
    print n.name()


#########OR###########


for n in hou.node("/obj").selectedChildren():
    print n.name()

load a scene and render a rop

#!/usr/bin/python2.5
import sys
sys.path.append(os.environ['HFS']+“/houdini/scripts/python”)
import hou
try:
    hou.hipFile.load(sys.argv[1])
except hou.LoadWarning, e:
    print e
except hou.OperationFailed:
    sys.exit(“Could not load “ + sys.argv[1])
rop = hou.node(“/out/OUT”)
rop.render()

get the path of the node

path = g.path()

list all nodes in scene

import hou
def print_tree(node, indent=0):
   for child in node.children():
     print " " * indent + child.name()
     print_tree(child, indent + 3)
     # Press Enter to finish the definition
print_tree(hou.node('/')) 

python equivalent of opscript command

xx = hou.node('/obj').createNode('geo')
CODE = xx.asCode()
print CODE

PARMTUPLES

hou_parm_tuple = hou_node.parmTuple("t")
hou_parm_tuple.set((0, 0, 0))
hou_parm_tuple.setAutoscope((True, True, True))
hou_parm_tuple.lock((False, False, False))

>>> # hou.Parm tuples correspond to parameter groupings:
>>> t = g.parmTuple('t')
>>> t
<hou.ParmTuple t in /obj/geo1>
>>> tuple(t)
(<hou.Parm tx in /obj/geo1>, <hou.Parm ty in /obj/geo1>, <hou.Parm tz in /obj/geo1>)
>>> t.eval()
(3.5, 0.0, 0.0)
>>> t.set((1.0, 2.0, 3.0))
>>> t.eval()
(1.0, 2.0, 3.0)