Dev:Ref/Release Notes/2.61/Python

Blender 2.61: Python

Changes up to revision 42577. Before editing or adding items, please read the guidelines for editing the changelogs.

Render Engine API

update_progress() function to update progress bar progress from external render engines. - r41201
.is_animation and .is_preview properties to detect if it's an animation or preview render that is being done. - r41463
RenderEngine is now a persistent python object that exists and retains properties as long as a frame is being rendered. This is mostly useful now that more than one callback will be added. - r41465
update() callback that should ideally be used to export the scene, leaving only the rendering to the render() callback. This is not required to be used at this point, but separating this will make things more thread safe later on. - r41465
Viewport rendering: - r41473
- view_draw() callback will do OpenGL drawing instead of the viewport.
- view_update() callback is called after depsgraph updates.
- tag_redraw() and tag_update() functions.

Persistent Callbacks

Ability to make callbacks persistent when new .blend files are loaded. - r41485, r41487

Example:

import bpy
from bpy.app.handlers import persistent

@persistent
def my_func(scene):
    pass

bpy.app.handlers.frame_change_pre.append(my_func)

Detecting Scene Updates

Functionality was added to detect when the scene changes, for example for external render engines that want to do interactive rendering.

Adds two new python handlers: scene_update_pre() and scene_update_post() These run before and after Blender does a scene update on making modifications to the scene. - r41476
Datablocks now have an is_updated property. This will be set to true in the above callbacks if the datablock was tagged to be updated. This works for the most common datablocks used for rendering: object, material, world, lamps, texture, mesh, curve. - r41476
Datablock collections also have an is_updated property. If this is set, it means one datablock of this type was added, removed or modified. It's also useful as a quick check to avoid looping over all datablocks. - r41476
RenderEngine.view_update() can also check these properties, for interactive viewport rendering. - r41476
Fix missing update after making modifications in frame_change_pre.

Update API documentation

Operator Presets

Operator presets now work in the 3D view, file selector and non-redo popups. - r41669, r41714

To enable for an operator:

bl_options = {'REGISTER', 'UNDO', 'PRESET'}

Library Datablocks

Optional collection subscript to contain the datablock library or None. - r41946, r42368

bpy.data.objects["Mesh", "/subsurf_test.blend"]

bpy.data.scenes["Scene", None]

# also works with get()
bpy.data.armatures.get(("some_armature", "//some_lib.blend"), None)

# and with contains test
if  ("Cube", "//lib.blend") in bpy.data.objects:
    pass

Noise Module

Noise module updated to new python API. - r42248

The noise module has now been moved to a submodule of mathutils, it can be accessed by mathutils.noise.
All functions which return vectors will now return mathutils.Vector types.
Different implementation of random_unit_vector is now used, to support 2D/3D/4D vectors instead of only 3D.
Naming: noise.vector is now noise.noise_vector and noise.vl_vector is now noise.variable_lacunarity
API documentation updated.

Other

Edit Source option when right clicking on buttons is now available in the release. This will open the python source file that controls the user interface at the line where the button is created. - r41210
List template: ability to add some controls for each list element - r41338
event.unicode so scripts can get unicode text input - r41215
Quaternion.to_axis_angle() added - r41460
mathutils.geometry.distance_point_to_plane(pt, plane_co, plane_no) - r41767
Include invalid type name in mathutils error messages. - r41774
Expose 3D view camera zoom and offset, needed if you want to precisely reconstruct camera parameters. - r41625
Rename SpaceFileBrowser.operator to active_operator. - r41625
Added context member 'active_operator' - r41669
Mesh.validate extended to remove invalid custom data layers - r41281
Mesh.validate() improved to handle invalid vertex groups, NaN values, zero normals r42528, r42324
ID property support for raw byte strings (non-null terminated) - r41861
Functions for adding int/float/string properties on mesh faces r41876
scene.render.layers.new()/remove() functions added - r41957
bgpic.add() renamed to new(), remove() added - r41965
mathutils.geometry.intersect_plane_plane added - r42000
clear() method added for most collections that support new()/remove() - r42091