The addons panel draw function calls addon_utils.modules() which in turn retrieves a list of fake modules from the script paths every time. This can become costly when network paths are included for
addons. Solution is to put the scanning process into a dedicated "refresh" function and disable it in frequently called draw and filter functions, i.e. in these cases the cached addons_fake_modules list
will be used instead.
Note that this may lead to invalid addon lists if script paths are changed (which is not working 100% without restart anyway according to Campbell). For this there is now a "Refresh" operator button in
the addons preferences. If necessary and feasible such forced refreshes can be added later too.
builtin classes. This was done in Python 2.3 to prevent changes to the 'object' type definition and similar issues. As explained by Guido van Rossum in the following mail, the python check will look for
the *closest* base class, which fails for RNAMetaPropGroup because its first base is RNAMeta, which is in turn a subclass of 'type'.
http://code.activestate.com/lists/python-dev/34489/
The easiest and safest way to prevent this issue therefore seems to be
to swap the base class order for RNAMetaPropGroup, so that StructMetaPropGroup is the first base, which has a perfectly valid setattr implementation.
there are cases where you want to use visual-keying but not remove constraints, also it wasnt obvious that clearing constraints used a different method of keyframing.
So split these into 2 options.
non-group trees (node trees not in the bpy.data.node_groups collection) to avoid confusion. For that purpose a new optional poll function argument has been added to NodeItem, which allows selectively
polling individual items in an otherwise static list.
* Remove difflib's quick_ratio() call, from quick tests looks it is four times slower than ratio(), and yet it gives the same results...
* Moved code to find all po's in a dir into its own func (will be used by i18n addon tools too).
As some people have already noticed, the "Add" menu for nodes is a bit messy since pynodes merge. The reason for this is that the order of nodes in submenus (categories) was previously defined by the order in which all nodes are registered (at the bottom of blenkernel/intern/node.c). For the dynamic registration of node types now possible this system of defining node order along with registration is no longer viable: while it would still sort of work for C nodes, it is completely meaningless for dynamic (python) nodes, which are basically registered automatically in whatever order modules and addons are loaded, with the added complexity of unloading and reloading.
To fix this problem and add a bunch of desirable features this commit replaces the C menu with a python implementation. The new menu does not rely on any particular order of types in the node registry, but instead uses a simple explicit list of all the available nodes, grouped by categories (in scripts/nodeitems_builtins.py).
There are a number of additional features that become possible with this implementation:
1) Node Toolbar can be populated!
The list of nodes is used to create 2 UI items for each node: 1 entry in a submenu of "Add" menu and 1 item in a node toolbar panel with basically the same functionality. Clicking a button in the toolbar will add a new node of this type, just like selecting an item in the menu. The toolbar has the advantage of having collapsible panels for each category, so users can decide if they don't need certain nodes categories and have the rest more easily accessible.
2) Each node item is a true operator call.
The old Add menu is a pretty old piece of C code which doesn't even use proper operator buttons. Now there is a generic node_add operator which can be used very flexibly for adding any of the available nodes.
3) Node Items support additional settings.
Each "NodeItem" consists of the basic node type plus an optional list of initial settings that shall be applied to a new instance. This gives additional flexibility for creating variants of the same node or for defining preferred initial settings. E.g. it has been requested to disable previews for all nodes except inputs, this would be simple change in the py code and much less intrusive than in C.
4) Node items can be generated with a function.
A callback can be used in any category instead of the fixed list, which generates a set of items based on the context (much like dynamic enum items in bpy.props). Originally this was implemented for group nodes, because these nodes only make sense when linked to a node tree from the library data. This principle could come in handy for a number of other nodes, e.g. Image nodes could provide a similar list of node variants based on images in the library - no need to first add node, then select an image.
WARNING: pynodes scripters will have to rework their "draw_add_menu" callback in node tree types, this has been removed now! It was already pretty redundant, since one can add draw functions to the Add menu just like for any other menu. In the future i'd like to improve the categories system further so scripters can use it for custom node systems too, for now just make a draw callback and attach it to the Add menu.
