Grouping nodes can simplify a node tree by allowing instancing and hiding parts of the tree.
Conceptually, grouping nodes allows you to specify a set of nodes that you can treat as though it were "just one node". Node groups are similar to functions in programming, they can be reused in many places in a node tree and can be customized by changing the "parameters" of the node group.
When a node group is created, new Group Input and Group Output nodes are generated to represent the data flow into and out of the group. Furthermore connections to input sockets coming from unselected nodes will become attached to new sockets on the Group Input node. Similarly, outgoing connections to input sockets of unselected nodes will become attached to the new Group Output node.
If you want to pass an additional parameter into the group, a socket must be added to the Group Input node. Therefore drag a connection from the hollow socket on the right side of the Group Input node to the desired input socket on the node requiring an input. The process is similar for the Group Output regarding data you want to be made available outside the group.
If you have multiple inputs or outputs, they can be re-ordered by selecting the socket in the list. And then moving them up or down with the arrow buttons on the right side of the panel. The plus button will add an unconnected socket of the same type as the selected socket or a value socket if there is no selection. The minus button will remove the selected socket. The triangle at the bottom of the list has filtering functions to help finding nodes if the group has a large number of sockets.
The name of the socket to display in the node's interface.
The message displayed when hovering over socket properties. Currently only supported for Geometry Node Editor
The value to use when nothing is connected to the node socket. Note, this will not affect the current node but will affect instances of the node.
The minimum and maximum value for the UI button shown in the node interface. Note, this is not a minimum or maximum for the data that can pass through the node. If a socket passes a higher value than the maximum it will still pass into the node unchanged.
Hide the socket value even when the socket is not connected.
选择节点组后， Tab 键可以将节点扩展为一个框，并显示其中的各个节点。可以把这些节点当作编辑器视图的其他正常节点一样，移动节点，修改控制选项，重新梳理其中的节点等。但是，你无法将它们连接到组外的节点；你必须使用节点组一侧的外部接口。Tab 可用于进入和退出节点组，但 Ctrl-Tab 只能退出节点组。
To create a node group, select the nodes you want to include, then press Ctrl-G,. A node group will have a green title bar. All selected nodes will now be contained within the node group. Default naming for the node group is "NodeGroup", "NodeGroup.001" etc. There is a name field in the node group you can click into to change the name of the group. Change the name of the node group to something meaningful.
When appending node groups from one blend-file to another, Blender does not make a distinction between material node groups or composite node groups. So it is recommended to use some naming convention that will allow you to distinguish between the two types.
Remember that the essential idea is that a group should be a reusable, self-contained software component. Material node groups should not include:
如果在组中包含源节点，则最终会使源节点出现 两次 ：一次出现在组内，一次出现在新材质节点树中的组外。
如果在组中包含输出节点，那么，该组就 不会 有输出接口！
The Ctrl-Alt-G tool removes the group and places the individual nodes into your editor workspace. No internal connections are lost, and now you can link internal nodes to other nodes in your workspace.
- 分离 P
Selecting a set of nodes, ending with the destination group node, and pressingwill move those nodes into that group. The moved nodes are collected into a group of their own to preserve their connection context, having their own group input and output nodes. The group's existing input and output nodes are updated with new sockets, if any, from the new nodes. The node group must be edited to contain a single Group Input and a single Group Output node.
将节点树添加到blender文件后，可以通过按 Shift-A,来选择附加组，并在节点编辑器中使用它。该组的 "控制面板" 包括各个分组的节点控件。你可以像处理任何其他节点一样使用组节点来更改它们。