Node Graph

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There really isn't that much to the Node Graph as such. Its just a blank sheet onto which the Nodes are arranged. Consider it a canvas onto which you paint. Perhaps more than any other aspect on Nuke, knowing the keystrokes makes a lot of difference to how easy it is to use.

Node tree layout

The nodes in a node graph look a bit like a tree... with one or many Read nodes at the top, and Write nodes at the bottom.

Nodes in a node graph. The nodes look a bit like a tree... With read nodes at the top, and a write node at the bottom.

It is, however, possible to lay the nodes out in Node Graph in many different ways. It consideration is not given to how it is done, then your working life can be made very bothersome. If you work collaboratively then this can make the lives of other people bothersome as well. If your co-workers have a set of house rules then I propose that you learn them asap, unless you want co-workers pissing in your coffee. In OART1035 you are to follow the script tidiness conventions laid out in here.

Tab menu

All of Nuke's nodes are stored in the Toolbar. However, if the 'Tab' key is pressed whilst the user is within the Node Graph, then the charming tab menu appears. As the user starts typing a list of Nodes appear in a drop-down menu. The arrow keys will navigate down or up the list and a hit on the enter key will summon that node.

The cute little tab menu.

Reading Nodes

Remember: scripts are not just meant to function, they are also meant to be read (by colleagues, by yourself and by your poor Nuke teacher). Reading scripts within the Node Graph is, for the most part, a fairly logical process. A script functions as a set of sequential actions from the top of the node tree, running downwards: e.g. Read followed by Multiply followed by Write. There is, however, a lot of hidden nuance to a script, a lot of which is found in some subtle niceties of the node interface.

In the set of nodes below. Through color and icons, each node tells us what changes there have been to the node stream:

A: The red, green and blue bars indicate that it is an RGB image.
B: To the RGB bars, a white bar has been added. This indicates that an alpha channel has been added. This is done automatically by many nodes.
C: The red dot in the top right corner, with 'A' in its Centre, indicates that this value has been animated.
D: The green dot with 'E' in the Centre, indicates that this node is being driven by an expression. If expressions arrows are made visible in the Node menu, then a green line will link to the node which drives the expression.
E: Here a channel other than RGBA added (e.g. A depth channel).
The 'in node' color coding of channels, animation etc.

In addition to 'in node' color coding, each 'family' of nodes is color-coded. The colors are prescribed according to the separate Tool sets. However, it only seems to apply to commonly used nodes. Others are boring grey. The color codes are:

Light green: The Draw nodes (Roto, RotoPaint etc)
Puke green: The Draw nodes (TimeClip, ReTime etc)
Purple red: The Draw nodes (Shuffle, ShuffleCopy etc)
Light blue: The Color nodes (Multiply, Grade, etc)
Orange: The Color nodes (Blur, Glow etc)
Neon green: The Color nodes (Keyer, Primatte etc)
Dark blue: The Merge nodes (Merge, Keymix etc)
Purple blue: The Transform nodes (Transform, Mirror etc)

The 3D nodes are designated by being different shape (rounded, apart from the ScanLineRender).

The color-coding of tool families.

Node Graph Keystroke Shortcuts

Node Graph Keystroke Shortcuts
Keystroke Action
Tab Summon the Tab Menu
D Disable selected node.
Shift X Swap inputs on node with two inputs (e.g. the Merge node).
Shift + select base node Select all upstream nodes.
Command click and drag on selected node Select all upstream nodes. Useful for moving groups of nodes around
Command, then click on yellow dots in Adds a dot to the connecting pipes.
Keystroke Shortcuts to Summon Specific Nodes
Keystroke Action
M Multiply
G Grade
C ColorCorrect
T Transform
R Read
W Write
M Merge
P Roto
S Project Settings
Keystroke Shortcuts Common to Most Panes
Keystroke Action
+ and - Zoom in and out (also scroll wheel).
F Fits and centres selected contents to pane (in the Viewer fits format to window, in the Node graph fits selected nodes to node graph etc).
Spacebar When panes are docked (i.e. not floating) this fills the workspace with the current pane).
option click + mouse drag Move the work space around within the pane.