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NUKE TCL PROCEDURES

This is a list of the TCL procedures in Nuke's plugins folder.

What are the TCL procedures?

If you have expirience with other programming languages common in VFX like Python or C++ you are probably used to creating function.

Here is a good explanation on the key differences.

So technically, TCL does not have functions. The closest thing to functions in TCL are procedures.

However, there is a subtle difference between functions and procedures in TCL.

In most programming languages, functions are first-class citizens. This means that they can be passed as arguments to other functions, and they can be returned by functions. Procedures in TCL are not first-class citizens. They cannot be passed as arguments to other procedures, and they cannot be returned by procedures.

This difference is mostly academic. In practice, procedures are used in TCL in the same way that functions are used in other programming languages.

The reason why TCL does not have true functions is historical. TCL was originally designed as a scripting language, and scripting languages typically do not have functions. However, TCL has evolved over time, and it is now used for a wider variety of tasks, including GUI development and system administration. As a result, there is a growing demand for functions in TCL.

Also, an example on how a simple procedure looks in TCL:

Where are the TCL procedures?

You can find the TCL procedures in the plugin folder where your Nuke app is installed.

Here is a little snippet you can run in the Script Editor to see them, just don't forget to update the "my_path" variable. Now you can find them!

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Most of these TCL procedures has been replaced by a python function since.

Those functions are part of the nukescripts module

However, there are cases where these procedures are still actively used and cases where the functions had been even removed too. Nonetheless, these procedures are still part of the

official Nuke package without extensive documentation.

How to use these procedures?

Many of the functions here are run when you are clicking somewhere in Nuke, but there are some that doesn't. These are standalone procedures you can run from Nuke's command line.

You can open it by pressing X over the NodeGraph.

Make sure you type them exactly as a procedure is called as TCL is case sensitive too.

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Is this the full list?

No, as most of the TCL files in the plugins folders are merely there to load in nodes from which most of them are not active in the toolbar but hidden ( can find a list of those here ).

As of now, on Nuke v14.0 there are 237 TCL files in the plugins folder.

There are 97 of them which aren't in charge of node creation so the list is focusing on those.

Can I see if these are still the procedures that Nuke

is running when clicking on something?

In most cases - Yes, in the Script Editor.

1 Open Preferences and set up Script Editor / echo python commends ...

2 Now, when you run a command you will see if it's using a tcl() interpreter function to execute the command. If so it is most likely coming from the plugin folder.

Keep in mind that not every TCL procedure in the pugin folder active in the app, many has been replaced with a python function.

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Of course, you can also find a menu.py in your plugins folder in which you can see that there are 13 commands that are still running tcl procedures:

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Why making this list?

First of all, want to make clear that the procedure codes here are the property of The Foundy.

The reasons I am making this list:

1 To have a better understanding on how Nuke works under the hood.

2 There aren't many Nuke related TCL resources on this level of complexity so it can help to offer new solutions for people to specific problems.

That said there are two useful documentations on Nukepedia that are under Foundry ownership:
Nuke tcl commands

Native tcl functions commonly used in Nuke

 

You can also open these sites from Nuke from Help / Documentation / TCL Scripting.

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The List

A
B
C
D
E
F
G
I
L
M
N
P
R
S
T
U
V
W

- A -

achannels

Shows a list of all available channels in the script. Basically, the same same as what channels does.

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allchars

Display a string of characters.

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animation_expressions

Opens the Curve Editor's Edit / Edit Expression window.

You can't use this proc in the command line, only inside a knob!

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The way to do that you need to type this proc inside square bracket inside the knob's 

expression window. If you do that it immediately shows another expression window:

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Although, this is a possbility to open this window this way it makes little sense to do so as it opens the expression window that is property of the Curve Editor as it is a window you can create there when you select a curve and go "right click / Edit / Edit Expression ". Also it will mess up the actual animation.

animation_filter

Runs the Curve Editor's Interpolation / Smooth function.

You can't use this proc in the command line, only inside a knob!

⚠ Applies on the curve as soon as you typed in the expression!

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animation_generate

Runs the Curve Editor's Edit/ Generate... function.

You can't use this proc in the command line, only inside a knob!

⚠ Opens  as soon as you typed in the expression!

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animation_loop

Runs the Curve Editor's Predefined / Loop function.

⚠ Opens  as soon as you typed in the expression!

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Oddly, when creating a Loop manually it ecoes the python code nukescripts.animation_loop()

instead of calling the TCL code that is part of tha package too but it works just as well if you run nuke.tcl('animation_loop') 

animation_move

Runs the Curve Editor's Edit / Move... function.

You can't use this proc in the command line, only inside a knob!

⚠ Opens  as soon as you typed in the expression!

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Oddly, the python function technically exist that is suppose to replace this procedure,  nukescripts.animation_move()  - but it seems like it didn't get finished as it only has the original TCL code commented under it.So when using the Move it runs nuke.tcl('animation_move') 

animation_negate

Runs the Curve Editor's Predefined / Negate function.

You can't use this proc in the command line, only inside a knob!

This might be broken as instead of using the negative values it makes the expression line longer the following way but not modifying the values:

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Looking at the result I just want to:

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When using athe Negate manually it echoes a python code nukescripts.animation_negate() 

animation_reverse

Runs the Curve Editor's Predefined / Reverse function.

You can't use this proc in the command line, only inside a knob!

This might be broken as instead of producing a reverse curve it doesn't seem to have any effect on the animation.

When using athe Reverse manually it echoes a python code nukescripts.animation_reverse() 

auto_connect

This procedure is most likely an earlier version of an improved current function.

You can find it under Edit / Node / Connect or can use the Y shortcut to connect the

last selected nodes.

The function that it runs called connectNodes which has a not too detailed entry in the API.

So let's dive into here what happens when using this function.

In the following examples I select first Blur1 then Blur2:

nuke.connectNodes(False, False)

Connects the node selected first to the one selected second.

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nuke.connectNodes(True, False)

Connects the node selected second to the one selected first.

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nuke.connectNodes(False, True)

Connects the node selected first to the one selected second using the node's second input.

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autocolor

This procedure is most likely an earlier solution of how the node's got their colour from the

that was set up in the preferences. Unfortunately, the name of the knobs are still changing as it used to be called "NodeColourClass<ID>" but on version14 it is "NodeColourSlot<ID>".

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autocolor_add

autocolor_node

autolabel

This procedure used to be in charge of featuring certain values on the node's name on the NodeGraph.

It is replaced now with the autolabel.py that can be find in the same plugins folder. This is the file that defines the values you can see displayed on certain nodes ( like the letters, representing operations when using ChannelMerge ).

Autolabel is also a very handy callback that you can modify in case you want to display certain values without using the `value` function on the label.

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This is a cool callback!

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autolabel_node

- B -

basename

Results as a base filename which is matching with what Read nodes displaying by default. You need to define the argument as a filename.

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branch

- C -

cache_clear

This procedure is supposed to clear cache but unfortunately, it isn't working anymore.

More interestingly this has a python function that has been removed from the package since version14.

So this might run on earlier versions but if you try to run it on versions above version14 you'll get the following error message "AttributeError: module 'nukescripts' has no attribute 'cache_clear'".

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nukescripts.cache_clear()

If you'd like to delete all cache you can do it manually at Cache / Clear All or use the 

clearAllCaches function:

nukescripts.clearAllCaches()

cache_report

cam_ver_panel

This procedure ( and the following ones ) are part of a system not used much these days but brings up a popup window with a cool name - Versionator. 😎

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camera_down

camera_up

camera_ver

color_nodes

This procedure brings up a colour palette when there are nodes selected and the chosen colour became the new tile_color for the selected nodes.

Can also find in the menu at Edit / Node / Color... or with the Ctrl+Shift+C shortcut.

It also has a python function with a shared source code.

nukescripts.color_nodes()

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copy_gizmo_to_group

This procedure should be a TCL version of the "Edit / Node / Group / Copy Gizmo To Group " or Ctrl+Shift+G function that you can also find in the API.
To run it you select a Gizmo first then run nuke.Gizmo.makeGroup(nuke.selectedNode())

 in the Script Editor.

The formula below to run the TCL version in the command line is:

[copy_gizmo_to_group [value IBKColourV3_1.name]]

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copy_knobs

This procedure should be a an earlier TCL version of the "Edit / Paste Knob Values" or Ctrl+Alt+V function that you can also find in the API with a source code.
To run it you need to Copy a node first then run nukescripts.misc.copy_knobs(nuke.selectedNodes()) in the Script Editor while having one or multiple nodes with a same class selected.

copy_to_group

This is basically the repacked copy_gizmo_to_group procedure from above.

create_curve

This procedure creates the dialog window thatallows you to create a new curve in

the Project Settings / Color.

You can do that manually, when clicking on the + sign:

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This procedure also has a python version with a shared source code. 

So you can also run these in the Script Editor:

nukescripts.create.create_curve()

nuke.tcl('create_curve')

One thing to be aware of is that instead of creating a new curve this creates a new user knob on 

the Project Settings panel. That user knob will be animated when using the python function and not animated if you create with a tcl procedure:

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create_read

This procedure opens a file browser to create a Read node.

This one also has a python version with a shared source code. 

So you can also run these in the Script Editor:

nukescripts.create.create_read()

nuke.tcl('create_read')

You can see that a python version is more advanced, a great extra feature there is that if you have a Read node selected it opens a file path already filled with that node's file value.

- D -

date

This procedure results in a current date.

The code very kindly includes different variables that can be useful to summon differenttime formats.

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declone

This procedure also has a python version with a shared source code. 

So you can also run these in the Script Editor:

nukescripts.misc.declone(nuke.selectedNode())

nuke.tcl('[declone [knob Blur1.name]]')

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default_font_pathname 

This tcl procedure runs a python function that gets the path to Nuke's default font..

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drop

This procedure is (probably) not active anymore as it also has a python version that you can see running when manually dropping an asset into the NodeGraph:

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- E -

execute_panel

This tcl procedure runs a python function ( for which we have a source code for ) and opens the 

execute dialog for a list of nodes. Can run the TCL procedure in the following ways:

[execute_panel [selected_node]]

[execute_panel [value Write1.name]]

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The result should be this window:

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And here is the way to run the python function in the Sript Editor:

nukescripts.execute.execute_panel(nuke.selectedNodes())

export_ascii

Runs the Curve Editor's File / Export Ascii... function.

This is one of those cases where Nuke still runs this tcl procedure so there is no python version.

You can't use this proc in the command line, only inside a knob!

⚠ Opens  as soon as you typed in the expression!

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export_chan

You can't use this proc in the command line, only inside a knob!

⚠ Opens  as soon as you typed in the expression!

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export_chan_file

export_chan_menu

export_discreet_lut

extract

This procedure also has a python version with a shared source code that is funnily enough just

points to a different function.

So you can also run these in the Script Editor:

nukescripts.edit.extract()

nuke.extractSelected()

nuke.tcl('extract')

When you run this procedure / function you are removing a selected node/nodes from the pipe:

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- F -

filter_multiple

Runs the Curve Editor's Edit/ Filter function.

You can't use this proc in the command line, only inside a knob!

⚠ Opens  as soon as you typed in the expression!

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fixclone

flipbook

In interesting old way to open a Flipbook. Wish I could use it!

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formats

This procedure hasn't survived as a python function in this form, but instead got a different approach on how Formats are handled with python in Nuke. ( Just don't forget the parenthesis after print even if the Foundry did ) ;)

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- G -

get_reads

This procedure also has a python version with a shared source code that also mentiones the accepted methods.

So you can also run these in the Script Editor:

nukescripts.reads.get_reads('file')

nukescripts.reads.get_reads('dir')

nukescripts.reads.get_reads('long')

getenv

This procedure shows the value of specific environment variables

You can find other useful info about environment variables here.

Let's use NUKE_TEMP_DIR as an example.

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Here's a python version to get the same value using the Script Editor:

import os

os.environ['NUKE_TEMP_DIR']

You can also feature these values in different places:

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goofy_title

This procedure also has a python version with a shared source code, unfortunately that doesn't include the list of goofy titles but expects you to create a txt file with them. But you can run this too:

nukescripts.goofy_title()

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goto_frame

This procedure brings up a dialog window asking for a frame number to move the viewer to. Also has  a python version with a shared source code

nukescripts.goto_frame()

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- I -

import_action

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import_adobe_lut

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import_ascii

Runs the Curve Editor's File / Import Ascii.. function.

⚠ Opens  as soon as you typed in the expression!

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import_boujou

This procedure from Nuke v5.0 brings up a file search window to select a .txt file. 

How to use this procedure is also mentioned on the official website, also on Nuke v6'.3s manual.

Also has  a python version with a shared source code, so you can also run thisin the Script Editor:

nukescripts.import_boujou()

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import_chan

import_chan_button

import_chan_button

import_chan_menu

This is a procedure that runs when you click on Import chan file on a Camera:

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It needs a node value so to run in the Script Editor would look like this:

nuke.tcl("import_chan_menu [node Camera1]")

import_discreet

This procedure is (probably) an older version of the following "import_discreet_lut".

⚠ Opens  as soon as you typed in the expression!

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import_discreet_lut

When running this procedure a file search window open expecting a .lut file.

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import_sequence

This is the procedure that gets executed when clicking on the Read node's import sequence to load in .edl file:

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infoviewer

This procedure brings up a window showing information about a single selected node.

You can also press "i" to open this window. 

Also has  a python version with a shared source code, - it shows that it is basically another function that gathers the info so if you don't need a pop up window can also use that:

nukescripts.getallnodeinfo()

nukescripts.infoviewer()

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init

invert

- L -

load_all_plugins

This procedure is an outdated version of the following python function

( see also at "update_all_plugin_menu") : 

nukescripts.update_plugin_menu("All plugins")

The procedure meant to load in all plugins in the Other menu on the Toolset:

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Instead it is resulting in the following error message:

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lset

- M -

makescratch

max_curve

min_curve

- N -

nfb_this 

node_copypaste

This procedure also has a python version with a shared source code

nukescripts.node_copypaste()

node_cutpaste

node_delete

This procedure also has a python version with a shared source code

nukescripts.node_delete()

The previous function ( and procedure ) deletes the selected nodes but there is a 

more commonly used delete function, that needs a node as an argument:

for n in nuke.selectedNodes():

nuke.delete(n)

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node_status 

nukev

This procedure creates a new Viewer, with a name NukeViewer.

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- P -

parray

paste_to_selected

- R -

read_file

remove_inputs

This procedure disconnects the selected nodes' first input. Also has a python version with a shared source code.

So you can also run this in the Script Editor:

nukescripts.remove_inputs()

As this procedure/function's use is limited it's recommended to use a newer function,

extractSelected() instead.

- S -

script_command

This procedure bring up a script command window. Also has a python version with a shared source code.

So you can also run this in the Script Editor to bring up the Command window:

nukescripts.script_command('')

Running the TCL procedure shows the number of threads by default:

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script_data 

This procedure brings up certain data about the script. This is a 2 part procedure where "get_script_data" is fetching the info and "script_data" organising on a prop up window that has a scroll too. So it has two python versions. One if you want to result in a popup window with a source code, and one if want to see the result in a Script Editor with source code.

nukescripts.script_data()

nukescripts.get_script_data()

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script_data 

This very touching mother's day present results in a script's and all the elements' location.

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script_version_up

This procedure versions up your script. It also has a python function with a shared source code.

nukescripts.script_version_up()

scroll_scr

Founding the result of this procedure is rather confusing. Feels like people had little faith that Nuke will have higher versions than 3 at the time. 😅

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search_plugins

search_replace

This procedure replaces parts of string on selected node's file path value. You can find this feature on the Edit / Node / Filename / Search and Replace...It also has a python function with a

shared source code

nukescripts.search_replace()

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search_by_name

This procedure brings up a Search pop up window and let's you add a string and based on that value selects nodes. You can use the " / " shortcut too. It also has a shared source code. You can see that under the hood it runs another function  ( selectPattern ) so can use either of these:

nukescripts.select_by_name()

nuke.selectPattern()

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select_similar

This procedure is the origin of a function that allows you to select similar nodes based on Color, Class or Label. You can find this function under the Edit / Select Similar menu.

It also has a shared source code too, but as it's mentioned in the description too it is recommended to use another function ( selectSimilar using one of the following arguments: nuke.MATCH_CLASS, nuke.MATCH_LABEL, nuke.MATCH_COLOR) instead:

nuke.selectSimilar(nuke.MATCH_CLASS)

setenv

showname

This procedure brings up a pop up window that shows the project's name value and a selected node's file value. It also has a shared source code. You can also get the same value from the root's name knob:

nukescripts.showname()

print(nuke.toNode('root')['name'].value())

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start

This procedure opens a website in your default browser. It also has a shared source code.

( Which oddly also runs the TCL code under the hood. )

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swapAB 

This procedure swaps the first two inputs of a node that's given as a value. It also has a shared source code which also considers if the node is a Group and the "lock all connection" knob is enabled.

nukescripts.swapAB(nuke.selectedNode())

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- T -

toggle

This procedure toggles checkbox values on selected nodes.

It also has a python function with a shared source code.

nukescripts.toggle("disable")

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toolbar

This procedure defines toolbar elements.

It has broken down to different functions under nukescripts.toolbars with shared sourcecodes.
Main one being setup_toolbars that isn't in use anymore.

There's also a newer function available, nuke.toolbar() .

topnode

This procedure returns the top node of the pipe where it's called

Unfortuntely, this clever procedure doesn't have an official python function version.

Luckily Anthony Tan has a super useful python tutorial series and he makes one in one of the episodes!
Kudos sir!

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- U -

UIchooser