Dev:JA/Ref/Release Notes/4.40/python api

元記事：Python API - Blender Developer Documentation

Blender 4.4: Python API¶

互換性のなくなる変更

Subclassing Blender Types¶

Python-defined classes based on Blender types (like Operator, PropertyGroup, etc.) that define their own __new__/__init__ constructors must now call the parent's matching function, and pass on generic positional and keyword arguments:

import bpy
class AwesomeRaytracer(bpy.types.RenderEngine):
    def __init__(self, *args, **kwargs):
        super().__init__(*args, **kwargs)
        ...

Paint¶

• paint.brush and paint.eraser_brush are now read-only properties. (9e8c037375)

GPU¶

• When drawing with POLYLINE_FLAT_COLOR, POLYLINE_SMOOTH_COLOR or POLYLINE_UNIFORM_COLOR or when drawing wide lines (line width greater than 1) using FLAT_COLOR, SMOOTH_COLOR or UNIFORM_COLOR, the following rules now apply:

  • The pos attribute must use F32 format FLOAT fetch type.
  • The color attribute must use F32 format with FLOAT fetch type or use U8 with 4 components and INT_TO_FLOAT_UNIT for fetch mode.
  • Each attribute needs to be 4 byte aligned.
  • Primitive type needs to be GPU_PRIM_LINES, GPU_PRIM_LINE_STRIP or GPU_PRIM_LINE_LOOP.
  • If drawing using an index buffer, it must contain no primitive restart index.

Grease Pencil¶

• The influence vertex group was removed from the Texture Mapping modifier (c452d5d9e8)

Video Sequencer¶

• The bpy.types.Sequence and all related types were renamed to bpy.types.Strip. See the full list below.
• Text strip align_x and align_y were renamed to anchor_x and anchor_y. Property alignment_x does proper alignment now. (77a5478c0f)

User Interface¶

• UILayout.template_icon() displays built-in icons in a normal size, not scaled up to fit the button. (1f88645728)

Actions¶

• Actions now have Slots, which requires changes to action assignment and editing. See the detailed explanation below for how to update.

Additions¶

bpy.app¶

• Attribute bpy.app.portable indicates if Blender's installation is portable, matching the WITH_INSTALL_PORTABLE build option. (481a8b67d4)
• Attribute bpy.app.module indicates if Blender is running as a Python module. (a6b293daac)

Grease Pencil¶

• Added a setter for the drawing property on frame python API (dc6e879d0f).
  • Can be used to copy a drawing from elsewhere (e.g. another layer or object): frame.drawing = other_drawing.
• Added a new property is_expanded to layer groups (e5bdfd533b). This returns True if the layer group is expanded in the layer tree UI.
• Added a function to reorder strokes in a drawing: drawing.reorder_strokes(new_indices=[...]) (a265b591be).
• Added a color_tag enum property to layer groups that exposes the color tag (36d69e8491).
• The influence vertex group was removed from the Texture Mapping modifier (c452d5d9e8)

Curves¶

• New Curves.reorder_curves(new_indices=[...]) to reorder curves. (a265b591be)
• New Curves.set_types() to change curve types (5db88ff2e3).

Nodes¶

• New Node.color_tag property, which returns an enum item corresponding to the node color tag (Texture, Vector, Output, etc...) (6cd33510c3)
• New bl_use_group_interface property on custom node trees that allows disabling some built-in UI for node groups (ebfbc7757b).

Blender as a Python Module¶

The bpy package on PyPI now provides access to VFX libraries used by Blender. (PR#133082)

While most are available as separate packages on PyPI, they may not have the same version or build options as Blender. This can lead to errors when interchanging data with Blender, which are resolved by using the matching version.

import bpy

# Add Blender bundled VFX libraries to sys.path.
bpy.utils.expose_bundled_modules()

# Import the library you need.
import pxr
import MaterialX
import OpenImageIO
import PyOpenColorIO
import pyopenvdb

Slotted Actions¶

Breaking¶

Assigning an Action (datablock.animation_data.action = some_action) may, under certain conditions, not auto-assign an action slot, hence leave the data-block in a non-animated state. To force assignment of the first slot of the action, follow up the assignment with datablock.animation_data.action_slot = some_action.slots[0]. This assumes that the first slot's target_id_type is either UNSPECIFIED or the same as datablock.id_type. This assumption holds for just-versioned Actions.

注意：Assigning Actions to an NLA strip or an Action constraint works slightly differently. Setting strip.action = some_action or constraint.action = some_action will always auto-assign the first slot that has a compatible target_id_type (docs). As such, this is actually backward-compatible as the state after the assignment is the same (the Action animates the thing).

Additions

Slotted Actions are part of an ongoing endeavour to make Actions fully layered. Even though layering is not supported yet, the data model is ready for layers and strips. This is reflected in the new API for slotted Actions.

import bpy

# Actions are created as before.
action = bpy.data.actions.new("SuzanneAction")

# Creation of slots requires an ID type and a name.
slot = action.slots.new(id_type='OBJECT', name="Suzanne")
print(f"slot type={slot.target_id_type} name={slot.name_display} identifier={slot.identifier}")
# Output:
#   slot type=OBJECT name=Suzanne identifier=OBSuzanne

# F-Curves and Channel Groups are now stored on an infinite keyframe strip that sits on a layer.
layer = action.layers.new("Layer")
strip = layer.strips.new(type='KEYFRAME')
channelbag = strip.channelbag(slot, ensure=True)

# F-Curves and Groups are created on the channelbag with the same API as previously on `action`.
# F-Curves and Groups themselves also still have exactly the same API as before.
fcurve = channelbag.fcurves.new("location", index=1)
group = channelbag.groups.new("Object Transform")
fcurve.group = group

# Assigning the Action will automatically select the slot, as it matches Suzanne's ID type + name:
suzanne = bpy.data.objects["Suzanne"]
anim_data = suzanne.animation_data_create()
anim_data.action = action

# If explicit slot assignment is needed:
anim_data.action_slot = action.slots[0]

# If there are multiple slots on the Action, and you want to just pick the first one that's
# compatible, use the following code. `anim_data.action_suitable_slots` can be used _after_ the
# Action has been assigned; it is a list of action slots of that Action, but only the ones that
# are actually compatible with the owner of anim_data (in this case, Suzanne).
anim_data.action_slot = anim_data.action_suitable_slots[0]

# Alternatively, you can set the 'last-used slot identifier' to determine which slot is auto-assigned:
anim_data.last_slot_identifier = 'OBDancing Monkey'
anim_data.action = action
print(anim_data.action_slot.identifier)
# Output: OBDancing Monkey, if that slot exists on the Action

注意：Even though the data model is ready for having multiple layers, and multiple strips per layer, Blender is currently limited to only a single layer with a single keyframe strip. The strip is infinitely long, and cannot be moved.

廃止予定

These legacy function / attributes of the Action type have been marked as 'backward-compatible legacy API'. They all operate on the data for the first action slot only, and create the necessary data structures where needed.

Legacy API	Modern API
action.fcurves	action.layers[0].strips[0].channelbag(action.slots[0]).fcurves
action.groups	action.layers[0].strips[0].channelbag(action.slots[0]).groups
action.id_root	action.slots[0].target_id_type

This legacy API will be removed in Blender 5.0

Video Sequencer Strips

Breaking

The type bpy.types.Sequence has been renamed to bpy.types.Strip together will all related types. (d3ba70190b)

Here is the full list:

4.3	4.4
bpy.types.Sequence	bpy.types.Strip
bpy.types.EffectSequence	bpy.types.EffectStrip
bpy.types.AddSequence	bpy.types.AddStrip
bpy.types.AdjustmentSequence	bpy.types.AdjustmentStrip
bpy.types.AlphaOverSequence	bpy.types.AlphaOverStrip
bpy.types.AlphaUnderSequence	bpy.types.AlphaUnderStrip
bpy.types.ColorMixSequence	bpy.types.ColorMixStrip
bpy.types.ColorSequence	bpy.types.ColorStrip
bpy.types.CrossSequence	bpy.types.CrossStrip
bpy.types.GammaCrossSequence	bpy.types.GammaCrossStrip
bpy.types.GaussianBlurSequence	bpy.types.GaussianBlurStrip
bpy.types.GlowSequence	bpy.types.GlowStrip
bpy.types.MulticamSequence	bpy.types.MulticamStrip
bpy.types.MultiplySequence	bpy.types.MultiplyStrip
bpy.types.OverDropSequence	bpy.types.OverDropStrip
bpy.types.SpeedControlSequence	bpy.types.SpeedControlStrip
bpy.types.SubtractSequence	bpy.types.SubtractStrip
bpy.types.TextSequence	bpy.types.TextStrip
bpy.types.TransformSequence	bpy.types.TransformStrip
bpy.types.WipeSequence	bpy.types.WipeStrip
bpy.types.ImageSequence	bpy.types.ImageStrip
bpy.types.MaskSequence	bpy.types.MaskStrip
bpy.types.MetaSequence	bpy.types.MetaStrip
bpy.types.MovieClipSequence	bpy.types.MovieClipStrip
bpy.types.MovieSequence	bpy.types.MovieStrip
bpy.types.SceneSequence	bpy.types.SceneStrip
bpy.types.SoundSequence	bpy.types.SoundStrip
bpy.types.SequenceColorBalanceData	bpy.types.StripColorBalanceData
bpy.types.SequenceColorBalance	bpy.types.StripColorBalance
bpy.types.SequenceCrop	bpy.types.StripCrop
bpy.types.SequenceElement	bpy.types.StripElement
bpy.types.SequenceElements	bpy.types.StripElements
bpy.types.SequenceModifier	bpy.types.StripModifier
bpy.types.SequenceModifiers	bpy.types.StripModifiers
bpy.types.SequenceProxy	bpy.types.StripProxy
bpy.types.SequenceTransform	bpy.types.StripTransform
bpy.types.SequencesMeta	bpy.types.StripsMeta
bpy.types.SequencesTopLevel	bpy.types.StripsTopLevel

Deprecated¶

Properties that refer to a bpy.types.Strip (previously bpy.types.Sequence) as "sequence" have been deprecated. New properties with "strip" are added. The old properties remain available until 5.0 but addon developers are encouraged to update their addons to use the new property names:

Deprecated property	New property
context.active_sequence_strip	context.active_strip
context.selected_editable_sequences	context.selected_editable_strips
context.selected_sequences	context.selected_strips
context.sequences	context.strips
SequenceEditor.sequences	SequenceEditor.strips
SequenceEditor.sequences_all	SequenceEditor.strips_all
MetaStrip.sequences	MetaStrip.strips