Files
test/scripts/startup/bl_operators/node.py
Lukas Tönne 5ad49f4142 Geometry Nodes: Menu Switch Node
This patch adds support for _Menu Switch_ nodes and enum definitions in
node trees more generally. The design is based on the outcome of the
[2022 Nodes Workshop](https://code.blender.org/2022/11/geometry-nodes-workshop-2022/#menu-switch).

The _Menu Switch_ node is an advanced version of the _Switch_ node which
has a customizable **menu input socket** instead of a simple boolean.
The _items_ of this menu are owned by the node itself. Each item has a
name and description and unique identifier that is used internally. A
menu _socket_ represents a concrete value out of the list of items.

To enable selection of an enum value for unconnected sockets the menu is
presented as a dropdown list like built-in enums. When the socket is
connected a shared pointer to the enum definition is propagated along
links and stored in socket default values. This allows node groups to
expose a menu from an internal menu switch as a parameter. The enum
definition is a runtime copy of the enum items in DNA that allows
sharing.

A menu socket can have multiple connections, which can lead to
ambiguity. If two or more different menu source nodes are connected to a
socket it gets marked as _undefined_. Any connection to an undefined
menu socket is invalid as a hint to users that there is a problem. A
warning/error is also shown on nodes with undefined menu sockets.

At runtime the value of a menu socket is the simple integer identifier.
This can also be a field in geometry nodes. The identifier is unique
within each enum definition, and it is persistent even when items are
added, removed, or changed. Changing the name of an item does not affect
the internal identifier, so users can rename enum items without breaking
existing input values. This also persists if, for example, a linked node
group is temporarily unavailable.

Pull Request: https://projects.blender.org/blender/blender/pulls/113445
2024-01-26 12:40:01 +01:00

459 lines
14 KiB
Python

# SPDX-FileCopyrightText: 2012-2023 Blender Authors
#
# SPDX-License-Identifier: GPL-2.0-or-later
from __future__ import annotations
import bpy
from bpy.types import (
Operator,
PropertyGroup,
)
from bpy.props import (
BoolProperty,
CollectionProperty,
EnumProperty,
FloatVectorProperty,
StringProperty,
)
from mathutils import (
Vector,
)
from bpy.app.translations import (
pgettext_tip as tip_,
pgettext_rpt as rpt_,
)
class NodeSetting(PropertyGroup):
value: StringProperty(
name="Value",
description="Python expression to be evaluated "
"as the initial node setting",
default="",
)
# Base class for node "Add" operators.
class NodeAddOperator:
use_transform: BoolProperty(
name="Use Transform",
description="Start transform operator after inserting the node",
default=False,
)
settings: CollectionProperty(
name="Settings",
description="Settings to be applied on the newly created node",
type=NodeSetting,
options={'SKIP_SAVE'},
)
@staticmethod
def store_mouse_cursor(context, event):
space = context.space_data
tree = space.edit_tree
# convert mouse position to the View2D for later node placement
if context.region.type == 'WINDOW':
# convert mouse position to the View2D for later node placement
space.cursor_location_from_region(
event.mouse_region_x, event.mouse_region_y)
else:
space.cursor_location = tree.view_center
# Deselect all nodes in the tree.
@staticmethod
def deselect_nodes(context):
space = context.space_data
tree = space.edit_tree
for n in tree.nodes:
n.select = False
def create_node(self, context, node_type):
space = context.space_data
tree = space.edit_tree
try:
node = tree.nodes.new(type=node_type)
except RuntimeError as ex:
self.report({'ERROR'}, str(ex))
return None
for setting in self.settings:
# XXX catch exceptions here?
value = eval(setting.value)
node_data = node
node_attr_name = setting.name
# Support path to nested data.
if '.' in node_attr_name:
node_data_path, node_attr_name = node_attr_name.rsplit(".", 1)
node_data = node.path_resolve(node_data_path)
try:
setattr(node_data, node_attr_name, value)
except AttributeError as ex:
self.report(
{'ERROR_INVALID_INPUT'},
rpt_("Node has no attribute %s") % setting.name)
print(str(ex))
# Continue despite invalid attribute
node.select = True
tree.nodes.active = node
node.location = space.cursor_location
return node
@classmethod
def poll(cls, context):
space = context.space_data
# needs active node editor and a tree to add nodes to
return (space and (space.type == 'NODE_EDITOR') and
space.edit_tree and not space.edit_tree.library)
# Default invoke stores the mouse position to place the node correctly
# and optionally invokes the transform operator
def invoke(self, context, event):
self.store_mouse_cursor(context, event)
result = self.execute(context)
if self.use_transform and ('FINISHED' in result):
# removes the node again if transform is canceled
bpy.ops.node.translate_attach_remove_on_cancel('INVOKE_DEFAULT')
return result
# Simple basic operator for adding a node.
class NODE_OT_add_node(NodeAddOperator, Operator):
"""Add a node to the active tree"""
bl_idname = "node.add_node"
bl_label = "Add Node"
bl_options = {'REGISTER', 'UNDO'}
type: StringProperty(
name="Node Type",
description="Node type",
)
# Default execute simply adds a node.
def execute(self, context):
if self.properties.is_property_set("type"):
self.deselect_nodes(context)
self.create_node(context, self.type)
return {'FINISHED'}
else:
return {'CANCELLED'}
@classmethod
def description(cls, _context, properties):
nodetype = properties["type"]
bl_rna = bpy.types.Node.bl_rna_get_subclass(nodetype)
if bl_rna is not None:
return tip_(bl_rna.description)
else:
return ""
class NodeAddZoneOperator(NodeAddOperator):
offset: FloatVectorProperty(
name="Offset",
description="Offset of nodes from the cursor when added",
size=2,
default=(150, 0),
)
def execute(self, context):
space = context.space_data
tree = space.edit_tree
self.deselect_nodes(context)
input_node = self.create_node(context, self.input_node_type)
output_node = self.create_node(context, self.output_node_type)
if input_node is None or output_node is None:
return {'CANCELLED'}
# Simulation input must be paired with the output.
input_node.pair_with_output(output_node)
input_node.location -= Vector(self.offset)
output_node.location += Vector(self.offset)
# Connect geometry sockets by default.
# Get the sockets by their types, because the name is not guaranteed due to i18n.
from_socket = next(s for s in input_node.outputs if s.type == 'GEOMETRY')
to_socket = next(s for s in output_node.inputs if s.type == 'GEOMETRY')
tree.links.new(to_socket, from_socket)
return {'FINISHED'}
class NODE_OT_add_simulation_zone(NodeAddZoneOperator, Operator):
"""Add simulation zone input and output nodes to the active tree"""
bl_idname = "node.add_simulation_zone"
bl_label = "Add Simulation Zone"
bl_options = {'REGISTER', 'UNDO'}
input_node_type = "GeometryNodeSimulationInput"
output_node_type = "GeometryNodeSimulationOutput"
class NODE_OT_add_repeat_zone(NodeAddZoneOperator, Operator):
"""Add a repeat zone that allows executing nodes a dynamic number of times"""
bl_idname = "node.add_repeat_zone"
bl_label = "Add Repeat Zone"
bl_options = {'REGISTER', 'UNDO'}
input_node_type = "GeometryNodeRepeatInput"
output_node_type = "GeometryNodeRepeatOutput"
class NODE_OT_collapse_hide_unused_toggle(Operator):
"""Toggle collapsed nodes and hide unused sockets"""
bl_idname = "node.collapse_hide_unused_toggle"
bl_label = "Collapse and Hide Unused Sockets"
bl_options = {'REGISTER', 'UNDO'}
@classmethod
def poll(cls, context):
space = context.space_data
# needs active node editor and a tree
return (space and (space.type == 'NODE_EDITOR') and
(space.edit_tree and not space.edit_tree.library))
def execute(self, context):
space = context.space_data
tree = space.edit_tree
for node in tree.nodes:
if node.select:
hide = (not node.hide)
node.hide = hide
# Note: connected sockets are ignored internally
for socket in node.inputs:
socket.hide = hide
for socket in node.outputs:
socket.hide = hide
return {'FINISHED'}
class NODE_OT_tree_path_parent(Operator):
"""Go to parent node tree"""
bl_idname = "node.tree_path_parent"
bl_label = "Parent Node Tree"
bl_options = {'REGISTER', 'UNDO'}
@classmethod
def poll(cls, context):
space = context.space_data
# needs active node editor and a tree
return (space and (space.type == 'NODE_EDITOR') and len(space.path) > 1)
def execute(self, context):
space = context.space_data
space.path.pop()
return {'FINISHED'}
class NodeInterfaceOperator():
@classmethod
def poll(cls, context):
space = context.space_data
if not space or space.type != 'NODE_EDITOR' or not space.edit_tree:
return False
if space.edit_tree.is_embedded_data:
return False
return True
class NODE_OT_interface_item_new(NodeInterfaceOperator, Operator):
'''Add a new item to the interface'''
bl_idname = "node.interface_item_new"
bl_label = "New Item"
bl_options = {'REGISTER', 'UNDO'}
item_type: EnumProperty(
name="Item Type",
description="Type of the item to create",
items=(
('INPUT', "Input", ""),
('OUTPUT', "Output", ""),
('PANEL', "Panel", ""),
),
default='INPUT',
)
# Returns a valid socket type for the given tree or None.
@staticmethod
def find_valid_socket_type(tree):
socket_type = 'NodeSocketFloat'
# Socket type validation function is only available for custom
# node trees. Assume that 'NodeSocketFloat' is valid for
# built-in node tree types.
if not hasattr(tree, "valid_socket_type") or tree.valid_socket_type(socket_type):
return socket_type
# Custom nodes may not support float sockets, search all
# registered socket subclasses.
types_to_check = [bpy.types.NodeSocket]
while types_to_check:
t = types_to_check.pop()
idname = getattr(t, "bl_idname", "")
if tree.valid_socket_type(idname):
return idname
# Test all subclasses
types_to_check.extend(t.__subclasses__())
def execute(self, context):
snode = context.space_data
tree = snode.edit_tree
interface = tree.interface
# Remember active item and position to determine target position.
active_item = interface.active
active_pos = active_item.position if active_item else -1
if self.item_type == 'INPUT':
item = interface.new_socket("Socket", socket_type=self.find_valid_socket_type(tree), in_out='INPUT')
elif self.item_type == 'OUTPUT':
item = interface.new_socket("Socket", socket_type=self.find_valid_socket_type(tree), in_out='OUTPUT')
elif self.item_type == 'PANEL':
item = interface.new_panel("Panel")
else:
return {'CANCELLED'}
if active_item:
# Insert into active panel if possible, otherwise insert after active item.
if active_item.item_type == 'PANEL' and item.item_type != 'PANEL':
interface.move_to_parent(item, active_item, len(active_item.interface_items))
else:
interface.move_to_parent(item, active_item.parent, active_pos + 1)
interface.active = item
return {'FINISHED'}
class NODE_OT_interface_item_duplicate(NodeInterfaceOperator, Operator):
'''Add a copy of the active item to the interface'''
bl_idname = "node.interface_item_duplicate"
bl_label = "Duplicate Item"
bl_options = {'REGISTER', 'UNDO'}
@classmethod
def poll(cls, context):
if not super().poll(context):
return False
snode = context.space_data
tree = snode.edit_tree
interface = tree.interface
return interface.active is not None
def execute(self, context):
snode = context.space_data
tree = snode.edit_tree
interface = tree.interface
item = interface.active
if item:
item_copy = interface.copy(item)
interface.active = item_copy
return {'FINISHED'}
class NODE_OT_interface_item_remove(NodeInterfaceOperator, Operator):
'''Remove active item from the interface'''
bl_idname = "node.interface_item_remove"
bl_label = "Remove Item"
bl_options = {'REGISTER', 'UNDO'}
def execute(self, context):
snode = context.space_data
tree = snode.edit_tree
interface = tree.interface
item = interface.active
if item:
interface.remove(item)
interface.active_index = min(interface.active_index, len(interface.items_tree) - 1)
return {'FINISHED'}
class NODE_OT_enum_definition_item_add(Operator):
'''Add an enum item to the definition'''
bl_idname = "node.enum_definition_item_add"
bl_label = "Add Item"
bl_options = {'REGISTER', 'UNDO'}
def execute(self, context):
node = context.active_node
enum_def = node.enum_definition
item = enum_def.enum_items.new("Item")
enum_def.active_index = enum_def.enum_items[:].index(item)
return {'FINISHED'}
class NODE_OT_enum_definition_item_remove(Operator):
'''Remove the selected enum item from the definition'''
bl_idname = "node.enum_definition_item_remove"
bl_label = "Remove Item"
bl_options = {'REGISTER', 'UNDO'}
def execute(self, context):
node = context.active_node
enum_def = node.enum_definition
item = enum_def.active_item
if item:
enum_def.enum_items.remove(item)
enum_def.active_index = min(max(enum_def.active_index, 0), len(enum_def.enum_items) - 1)
return {'FINISHED'}
class NODE_OT_enum_definition_item_move(Operator):
'''Remove the selected enum item from the definition'''
bl_idname = "node.enum_definition_item_move"
bl_label = "Move Item"
bl_options = {'REGISTER', 'UNDO'}
direction: EnumProperty(
name="Direction",
description="Move up or down",
items=[("UP", "Up", ""), ("DOWN", "Down", "")]
)
def execute(self, context):
node = context.active_node
enum_def = node.enum_definition
index = enum_def.active_index
if self.direction == 'UP':
enum_def.enum_items.move(index, index - 1)
enum_def.active_index = min(max(index - 1, 0), len(enum_def.enum_items) - 1)
else:
enum_def.enum_items.move(index, index + 1)
enum_def.active_index = min(max(index + 1, 0), len(enum_def.enum_items) - 1)
return {'FINISHED'}
classes = (
NodeSetting,
NODE_OT_add_node,
NODE_OT_add_simulation_zone,
NODE_OT_add_repeat_zone,
NODE_OT_collapse_hide_unused_toggle,
NODE_OT_interface_item_new,
NODE_OT_interface_item_duplicate,
NODE_OT_interface_item_remove,
NODE_OT_tree_path_parent,
NODE_OT_enum_definition_item_add,
NODE_OT_enum_definition_item_remove,
NODE_OT_enum_definition_item_move,
)