Flags can change a knob’s appearance or behaviour. They are useful for doing things like:
Only a few knob flags are registered in Nuke’s Python module, which makes them a little difficult to use.
Some gizmos dynamically hide/show a number of knobs with the KnobChanged python callback. This is a good option to keep your gizmo's UI clean, but can start to get very heavy when you have too many knobs to handle, and too many nodes inside your gizmo.
Instead, it can be cleaner to use Python Script Buttons to add/remove knobs/nodes from your gizmo to keep things fast, neat and tidy.
I whipped up the following example node, which you can download here, to see how this works.
In Nuke, you're able to dynamically change any knob's value depending on if you're looking through a Viewer in Nuke's GUI, or rendering your Nuke script on a render farm. This can be useful to keep your Nuke scripts light & efficient while working, while automatically switching to more processor-intensive tasks at render time — for example, increasing motion blur render samples.
Gizmos Nuke Python VFX Industry Workflow
When adding a new gizmo to a menu inside of Nuke, I like to recycle the existing icons so I can keep everything thematically consistent. However, these icons are buried inside Nuke's install directory, and I always forget exactly where they live...
The beginning of my Compositing career started with After Effects, and while I'm now living and breathing Nuke, there's one thing I still miss -- the ease of use of After Effects' animation tools.
Coupled with a recent fascination with bezier curves, I decided to set out and see if I could bring the most basic functionality from After Effects, "easy ease", into Nuke, with a way to control the smoothness of that curve.
Comp Newsletter For Patreon Supporters Python
You might have seen gizmos with knobs that dynamically disable/enable, or hide/show, based on the value of another knob. This is achieved by accessing the knobChanged knob, which is hidden to users, and can be accessed via Python.
Something I'm endlessly frustrated by is having to work around the way Nuke uses confusing hex colour values in Python to do things such as set a node's tile_color knob. For example, how are we supposed to remember that 0xff000ff = green ? I wrote two simple functions to get around this, which I hope you can make use of too...
$gui expression to its samples knob. So, why not automate that? Here's my solution code for your menu.py first, explanation below):
Contact sheets are something I use all the time to run out wedges of certain looks & compare my work against other shots in the sequence. Although, the Contact Sheet node is kind of... basic. It lacks a few features & requires a lot of initial setup to actually be useful. The aim of this article is to share some knowledge on the defaults I have in my contact sheet node & how to set contact sheets up more-speedily.
Humans are creatures of habit. To align with this mindset, I have created a python script that enables compositors to set Backdrop Node presets in their menu.py!
You may have used a gizmo in the past where toggling a checkbox enables/disables a set of knobs, or choosing a certain value from a Pulldown Choice will hide or show another set of knobs. What wizardry is this??? At least that's what I asked myself when embarking on my first gizmo-creating frenzy...
After searching the web, I came across many threads in many forums explaining this mysterious thing called "knobChanged", accompanied by a load of copy/pasted code to explain how to use it. With my limited knowledge of Python at the time, I had no idea what any of it meant. I just wished there was someone who posted what I needed and that was it. If this describes you right now, you're in luck!
Nuke is incredibly flexible and customizable out of the box, and empowers artists to work they way they want to work to get a shot to final. But there's a whole other world of untapped potential when you utilize Python to further expand it! In this post, I'm going to show you an example of how even the most simple python script can save you time every day.
You may have heard other compositors refer to a menu.py, or a "preferences file" in the past. What the hell is that?!
A menu.py is a python file that Nuke will read upon starting up each time. It contains data such as:
Most studios will have a menu.py to setup specific things for the entire studio, as well as a second menu.py file to change certain things on a per-show basis. But you can also create your own menu.py to customize things for you, and you only! There is a lot of power in customizing Nuke to work in the most efficient manner, based off the way you think and operate.