Using the Node Editor
In this section, you’ll learn the Node Editor’s basic controls: how to create and modify nodes, connect them, and so on. Figure 14.4 shows the Node Editor with a simple setup example.
Navigation in the Node Editor is pretty straightforward because it uses the same Blender navigation tools as any other editor: MMB to pan and Scroll Wheel or Ctrl + MMB to zoom in and out.
Getting Started with the Node Editor
When you open the Node Editor, you must keep in mind that it’s also used for creating materials and textures. To use it for compositing, you need to select Compositing Mode on the header.
Once you’ve switched to Compositing Mode, you won’t immediately see any nodes. Before you can start using nodes, you need to enable them in your scene. Click the Use Nodes option in the header and Blender will display a very basic node setup: the render plugged to a Composite node. This means there is nothing interesting going on for now; the final render is not being processed at all after its generation, so you get the raw result from the 3D scene.
However, now the editor is ready for you to start experimenting with nodes. If you launch a render now, it will use the basic node tree you have just created. At some point, if you need to launch a “raw” render without using the nodes, just disable the Use Nodes option.
Creating Nodes
There are three ways to create nodes in the Node Editor:
From the Tools Region: The Tools Region of the Node Editor (T) has a panel for each type of node (categories) and, if you expand those panels, just click the node you want, move the new node until it is in the desired position, and left click to place the node in that location.
From the Add menu: On the Node Editor’s header, in the Add menu, you can select the type of node you want, left click it, move the new node to the desired position, and left click again to place the node in that location.
Pressing Shift + A: If you press Shift + A when in the Node Editor, the same Add menu from the header will appear at the cursor’s position. Just as with the other methods described above, once you click to select the node type you want, drag the new node to the correct location and left click to drop the node there.
Tip
When you place the new node you just created, if you drag it over a connection between two other nodes, the connection will be highlighted and when you left click to drop the new node, it will be automatically connected between those other two nodes. This is a big time saver!
Connecting and Manipulating Nodes
The basic method for working with nodes is to create connections between them to make them interact with each other. It’s also important to know how to move them around so your node tree is always organized. Otherwise, you can end up with a lot of nodes that overlap and that will make the tree very hard to work with.
Here is a list with the main controls for working with nodes:
You can select nodes with both LMB and with RMB. Drag nodes with LMB or RMB to move them around.
If you select more than one node with B (Box Selection) or with Shift + LMB, you can move them, rotate them, and scale them with G, R, and S, as always.
Right click and drag in an empty space to perform a Box Selection at that point.
To connect nodes, just left click and drag from one node’s output noodle to the desired input noodle of another node.
If a node has two or more input noodles and you want to switch a connection between them, just left click and drag from one noodle to the other.
You can select two nodes and press F to create a connection between them.
To remove a connection, left click the input noodle at the end of the connection, then drag it and drop it in an empty space.
To remove one or more connections quickly, press Ctrl + LMB click and drag a line over the connections you want to cut. When you release LMB, the connections under the cutting line will be removed.
Select one or more nodes and press M to mute them. Using the preview, this is an easy way to see the effect a node has on the resulting image. Nodes will become red when they’re muted. Press M again to enable them.
You can duplicate nodes or groups of connected nodes with Shift + D.
If you don’t need to access a node’s properties, press H when you select the node to collapse it so it takes less space. Press H again to expand it.
Select one or more nodes and press X to remove them. Press Ctrl + X to delete them while keeping the connections between their previous and next nodes.