Helpful documentation
Nuke Python Developer’s Guide
Nuke Python API
Knob Types
Some Flags
TCL:
Get input node name:
[value this.input0.name]
Set a variable in expression with TCL:
[set VARIABLENAME VALUE; return]
To use this variable later needs to type it as:
$VARIABLENAME
TCL String Operation that returns the 5th character from top input node name:
[string index [value [topnode this.input0].name] 5]
Use TCL string operation to converts to uppercase or lowercase:
[string tolower [value]]
Check if anything is plugged in to an input:
[exists this.input0]] if nuke.thisNode().input(0)
Check input1 and check if anything is plugged in:
[value [topnode this.input0].name] [exists parent.[string tolower [value [topnode this.input1].name]]]
This handy getting filename from topmost read I grabbed from Nukepedia
[lindex [split [lindex [split [knob [topnode].file] .] 0] /] end] [file dirname [knob [topnode].file]]/[lindex [split [lindex [split [knob [topnode].file] .] 0] /] end]_conv.%04d.exr
Get nuke script base name without file extension
[lindex [split [file rootname ] /] end]
Read metadata with TCL
[metadata input/filename]
Using expressions in Text node (needs to square bracket the whole thing):
[expression frame==1?1:0]
Get Bezier1’s point 0 (which is first point) position in Roto1 node :
[value Roto1.curves.Bezier1.curve_points.0.main]
Python:
Get the last letter/section from node name, separated by “_”:
nuke.thisNode().name().rsplit("_").__getitem__(2)
From the above, can be modified to acquire file extension
nuke.thisNode()['file'].getValue().rsplit(".").__getitem__(2)
Set expression with python found here, especially useful when setting expression to a dropdown menu which is usually not accessible
nuke.selectedNode()['antialiasing'].setExpression('$gui? 0:3')
List of all nodes but exclude selected ones:
n = nuke.allNodes()
for i in nuke.selectedNodes():
n.remove(i)
return n
Replace frame paddings (%04d) and extension with .mov
import re
v = nuke.toNode('Read1')['file'].value()
print re.sub(r'%.*d.exr', 'mov', v)
Search for frame paddings
f = nukescripts.replaceHashes(nuke.filename(n)) padd = re.search(r'%.*d', f) print padd.group(0)
Check if program exist from python script, from here
shutil.which
It was introduced in Python 3.3 and is cross-platform, supporting Linux, Mac, and Windows. It is also available in Python 2.x via whichcraft.
def is_tool(name):
"""Check whether `name` is on PATH and marked as executable."""
# from whichcraft import which
from shutil import which
return which(name) is not None
distutils.spawn.find_executable
def is_tool(name):
"""Check whether `name` is on PATH."""
from distutils.spawn import find_executable
return find_executable(name) is not None
Launch terminal via Python in different linux distros
from distutils.spawn import find_executable
def isNot_exec(name):
#check whether terminal program exists
return find_executable(name) is None
def findTerminal():
termList = ["x-terminal-emulator", "konsole", "gnome-terminal", "urxvt", "rxvt", "termit", "terminator", "Eterm", "aterm", "uxterm", "xterm", "roxterm", "xfce4-terminal", "termite", "lxterminal", "mate-terminal", "terminology", "st", "qterminal", "lilyterm", "tilix", "terminix", "kitty", "guake", "tilda", "alacritty", "hyper"]
#list taken from https://github.com/i3/i3/blob/next/i3-sensible-terminal
i = 0
for term in termList:
if isNot_exec(term):
i += 1
else:
break
return termList[i]
Get working directory in python
import os print os.getcwd()
Check if variable not equal to multiple things
while choice not in [1, 2, 3]:
Get filename from path
import os #Get filename with extension name = os.path.basename(path) #filename without extension os.path.splitext(name)[0] #extension is [1]
Check if node is gizmo
print 'gizmo_file' in nuke.selectedNode().knobs()
Get list of nodes inside selected gizmo
nodes = nuke.allNodes(group=nuke.selectedNode())