The node link operator had a feature to automatically expose sockets in node groups when ctrl+shift+clicking on a node socket, which would create a node group input/output node. This was intended as a shortcut but conflicts with other features such as socket selection and viewer creation. It is also hardly necessary now that input/output nodes have an extension socket, which is much easier to use. Removed this expose functionality completely.
Added a sanity check to the ED_node_link_insert function to ensure it exits gracefully if no suitable sockets can be found. This was the problem with custom pynodes, which don't define the 'type' DNA of old sockets. The operator will have to be generalized for future nodes, but for now just not crashing seems good enough.
Script node crashes in #34810 were caused by uninitialized 'type' integer as well. This is now done in the set_typeinfo function for sockets (like for trees and nodes too), to avoid any potential remaining issues of this kind. Note that new files need to be loaded and saved again once to be forward compatible again.
PyNodes opens up the node system in Blender to scripters and adds a number of UI-level improvements.
=== Dynamic node type registration ===
Node types can now be added at runtime, using the RNA registration mechanism from python. This enables addons such as render engines to create a complete user interface with nodes.
Examples of how such nodes can be defined can be found in my personal wiki docs atm [1] and as a script template in release/scripts/templates_py/custom_nodes.py [2].
=== Node group improvements ===
Each node editor now has a tree history of edited node groups, which allows opening and editing nested node groups. The node editor also supports pinning now, so that different spaces can be used to edit different node groups simultaneously. For more ramblings and rationale see (really old) blog post on code.blender.org [3].
The interface of node groups has been overhauled. Sockets of a node group are no longer displayed in columns on either side, but instead special input/output nodes are used to mirror group sockets inside a node tree. This solves the problem of long node lines in groups and allows more adaptable node layout. Internal sockets can be exposed from a group by either connecting to the extension sockets in input/output nodes (shown as empty circle) or by adding sockets from the node property bar in the "Interface" panel. Further details such as the socket name can also be changed there.
[1] http://wiki.blender.org/index.php/User:Phonybone/Python_Nodes
[2] http://projects.blender.org/scm/viewvc.php/trunk/blender/release/scripts/templates_py/custom_nodes.py?view=markup&root=bf-blender
[3] http://code.blender.org/index.php/2012/01/improving-node-group-interface-editing/
The operator names all show up in the Search button. As such is nicer if they
can all have the main words capitalized.
e.g. "Snap strips" should be "Snap Strips"
"Copy to clipboard" should be "Copy to Clipboard"
This was done with a mix of bash tools, regex, and manual work because I'm too rushed into regex :)
+ fix bge stereo eye separation tooltip
Note: While renaming DNA properties is usually dangerous and can break files, in this case it is possible because the mx/my values are only used at runtime.
