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.
- GLSL shader wasn't aware of alpha predivide option,
always assuming alpha is straight. Gave wrong results
when displaying transparent float buffers.
- GLSL display wasn't aware of float buffers with number
of channels different from 4, crashing when trying to
display image with different number of channels.
This required a bit larger changes, namely now it's
possible to pass format (GL_RGB, GL_RGBAm GL_LUMINANCE)
to glaDrawPixelsTex, This also implied adding format to
glaDrawPixelsAuto and modifying all places where this
functions are called.
Now GLSL will handle both 3 and 4 channels buffers,
single channel images are handled by CPU.
- Replaced hack for render result displaying with a bit
different hack.
Namely CPU conversion will happen only during render,
once render is done GLSL would be used for displaying
render result on a screen.
This is so because of the way renderer updates parts
of the image -- it happens without respect to active
render layer in image user. This is harmless because
only display buffer is modifying, but this is tricky
because we don't have original buffer opened during
rendering.
One more related fix here was about when rendering
multiple layers, wrong image would be displaying when
rendering is done. Added a signal to invalidate
display buffer once rendering is done (only happens
when using multiple layers). This solves issue with
wrong buffer stuck on the display when using regular
CPU display space transform and if GLSL is available
it'll make image displayed with a GLSL shader.
- As an additional change, byte buffers now also uses
GLSL display transform.
So now only dutehr and RGB curves are stoppers for
using GLSL for all kind of display transforms.
Historically, F shortcut was for 'add edge/face' in Blender.
In Node editor, F makes a noodle, ctrl+f made a noodle replace too.
To keep ALT+F work for "Unattach from frame", the solution I now propose
is to make CTRL+F for finding nodes, and SHIFT+F for 'add noodle with replace'.
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.
New operator "Find Node".
Opens search menu, and allows to find a node based on name or label.
On selecting name, menu selects/activates the node and moves the view to it.
Shortcut: ALT+F
Menu: Node editor, "Select"
To complete previous commit:
New "Activate same type next/prev" operator - replaces the two not working previous ones.
This selects/activates and views the next or previous node of same type.
Shortcuts: Shift ] and Shift [
This is the first half of the commit, it's going to be reviewed further.
It also depends on other work in node drawing (to not reshuffle order on
every select/activate).
At least it works quite nice for the shortcuts shift [ and shift ]
Draw an extra outline on hidden nodes that have custom colors, otherwise you can't recognize them unless you unhide.
Example: http://pasteall.org/pic/show.php?id=42359
Make it so compositor output node wouldn't be calculated
when Render Result image is not visible on the screen.
This makes compositor tree editing more friendly and
faster.
Also, if there's no viewer image visible on the screen
viewer nodes wouldn't be handled.
Final rendering keeps unchanged for now.
This solves issues when for performance artists are
disconnecting compo output node before tweaking values
in compositor and forgets to attach compo output
node before sending file to the farm.
showing pixels. Issue was it also blurred image at zoom level 1... maybe subpixel
issue. Anyway - for inspecting exact composite results, zooming in showing pixels
is nicer anyway.
When nodes are loaded from a .blend file they can potentially have undefined types. This can happen if a type has been deprecated and removed, or if node types were defined in a python script that has not been loaded correctly. Previously all such nodes would automatically be removed from a node tree, assuming that their types were deprecated and no longer in use (more commonly caused by loading new nodes in an older Blender version). Due to the possibility of dynamic registration it is no longer feasible to simply delete such nodes.
Display and handling of node trees was simply disabled before this patch, so that a node tree where any node or socket type was undefined would not be displayed at all. To give more information and avoid problems caused by necessary checks for the typeinfo pointer, there is now a 'Undefined' fallback type for trees, nodes and sockets. These types are used as placeholders in case the real type is not registered and can provide useful visual feedback on undefined nodes.
* If the node tree can be updated from context (tree has get_from_context callback defined), reset the pointers first to clear the editor path if no tree can be found.
* Stupid mistake: snode->from != snode->from is always false.
* Shader nodes context update: set the 'from' pointer to the active object, even if it doesn't have a material or node tree.
* Add, Move and Remove Socket operators missed a notifier for UI redraw.
Note: ND_DISPLAY seems to be for the Text editor only, according to WM_types.h, but seems to be used in quite a few places.
Time to cleanup notifiers 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/
