Adds operator handlers to operators. #117912

Jaume Bellet · 2024-02-06T18:32:19+01:00

Jaume Bellet commented

2024-02-06 18:32:19 +01:00

First-time contributor

Allows executing python code pre and post execution.

Motivation

I have found a needed to do something from python, when an operator is being executed.

Usage examples

An add-on is doing managing with geometry and needs to perform something when vertices are deleted.
An add-on could use translate operator to move something it controls, related to vertices positions.

Benefits

Addon's are not abusing on timers
Code if more event focused

Desing

Python example code

import bpy

#custom bpy operators
class SimpleOperator(bpy.types.Operator):
    """Tooltip"""
    bl_idname = "object.simple_operator"
    bl_label = "Simple Object Operator"

    @classmethod
    def poll(cls, context):
        return context.active_object is not None

    def execute(self, context):
        return {'FINISHED'}

bpy.utils.register_class(SimpleOperator)


# Any Python object can act as the handler owner.
owner = object()

# Poll
def handler_poll_true(context, event, params):
    return True

def handler_poll_false(context, event, params):
    return False

def handler_poll(context, event, params, arg):
    return arg == True

# Callbacks
def pre_invoke_callback(context, event, params):
    print("[PRE] invoke", params)
def post_invoke_callback(context, event, params, ret_code):
    print("[POST] invoke", params, "returned", ret_code)
    
def pre_invoke_callback_owner(context, event, params):
    print("[PRE] invoke (with owner)", params)
def post_invoke_callback_owner(context, event, params, ret_code):
    print("[POST] invoke (with owner)", params, "returned", ret_code)

def pre_invoke_callback_args(context, event, params, args):
    print("[PRE] invoke args", args, params)
def post_invoke_callback_args(context, event, params, ret_code, args):
    print("[POST] invoke args", params, "returned", ret_code, "args", args)

def pre_invoke_callback_owner_args(context, event, params, args):
    print("[PRE] invoke (with owner) args:", args, params)
def post_invoke_callback_owner_args(ctx, evt, params, ret_code, args):
    print("[POST] invoke (with owner)", params , "returned", ret_code, "args:", args)

def pre_invoke_callback_override(context, event, params):
    print ("Overrided")
    return False


def modal_callback(context, event, params, ret_code):
    print (context.active_object)
    print (event)
    print ("modal")
    
def modal_callback_args(context, event, params, ret_code, args):
    print (context.active_object)
    print (event.mouse_x, event.mouse_y)
    print ("modal", args)
    
def modal_end_callback(context, event, params, ret_code):
    print("modal end", ret_code)

def pre_invoke_custom_op_callback(context, event, params):
    print("[PRE] invoke custom operator", params )
def post_invoke_custom_op_callback(context, event, params, ret_code):
    print("[POST] invoke custom operator", params, ret_code)
    
# Registration
bpy.ops.mesh.primitive_cube_add.handlers.invoke_pre.append(pre_invoke_callback)
bpy.ops.mesh.primitive_cube_add.handlers.invoke_post.append(post_invoke_callback)

bpy.ops.mesh.primitive_cube_add.handlers.invoke_pre.append(cb=pre_invoke_callback_args, poll = handler_poll, args=(False,))
bpy.ops.mesh.primitive_cube_add.handlers.invoke_post.append(cb=post_invoke_callback_args, args=(1,))

bpy.ops.mesh.primitive_cube_add.handlers.invoke_pre.append(pre_invoke_callback_owner, owner)
bpy.ops.mesh.primitive_cube_add.handlers.invoke_post.append(post_invoke_callback_owner, owner)

bpy.ops.mesh.primitive_cube_add.handlers.invoke_pre.append(pre_invoke_callback_owner_args, owner,(1,))
bpy.ops.mesh.primitive_cube_add.handlers.invoke_post.append(post_invoke_callback_owner_args, owner,(1,))

bpy.ops.object.simple_operator.handlers.invoke_pre.append(pre_invoke_custom_op_callback)
bpy.ops.object.simple_operator.handlers.invoke_post.append(post_invoke_custom_op_callback)

#Showing the splash will not print "overrided" and do anything
bpy.ops.wm.splash.handlers.invoke_pre.append(pre_invoke_callback_override)


# Unregistration
# Remove one handler from pre_invoke
bpy.ops.mesh.primitive_cube_add.handlers.invoke_pre.remove(pre_invoke_callback)
#remove all handlers from post_invoke owned
bpy.ops.mesh.primitive_cube_add.handlers.invoke_post.remove(owner=owner)

# Remove all handlers owned
bpy.ops.remove_handlers(owner=owner)

# calling the MESH_OT_primitive_cube_add operator should output
"""
[POST] invoke {'size': 2.0, 'calc_uvs': False, 'enter_editmode': True, 'align': 0, 'location': (0.0, 0.0, 0.0), 'rotation': (0.0, 0.0, 0.0), 'scale': (1.0, 1.0, 1.0)} returned {'FINISHED'}
[POST] invoke args {'size': 2.0, 'calc_uvs': False, 'enter_editmode': True, 'align': 0, 'location': (0.0, 0.0, 0.0), 'rotation': (0.0, 0.0, 0.0), 'scale': (1.0, 1.0, 1.0)} returned {'FINISHED'} args 1
"""
# calling the OBJECT_OT_simple_operator()
# bpy.ops.object.simple_operator()
"""
[PRE] invoke custom operator {}
[POST] invoke custom operator {'FINISHED'}
"""

bpy.ops.transform.translate.handlers.modal.append(cb = modal_callback_args, args = (1,))
bpy.ops.transform.translate.handlers.modal.append(cb= modal_callback, poll = handler_poll_false)
bpy.ops.transform.translate.handlers.modal_end.append(modal_end_callback)

# Moving an object should output
"""
<bpy_struct, Object("Cube.001") at 0x0000028E8F0D7E08>
246 572
modal 1
...
modal end {'FINISHED'}
"""


def selection_cb(context, event, params,ret):
    print("SELECT", params, ret)
    
bpy.ops.view3d.select.handlers.invoke_post.append(selection_cb)

# Click on 3D view should output
"""
SELECT {'extend': True, 'deselect': True, 'toggle': True, 'deselect_all': False, 'center': True, 'enumerate': True, 'object': True, 'location': (222, 123)} {'PASS_THROUGH', 'FINISHED'}
"""

More

This was previously submitted on phabricator D10579 and

Allows executing python code pre and post execution. ## Motivation I have found a needed to do something from python, when an operator is being executed. ## Usage examples - An add-on is doing managing with geometry and needs to perform something when vertices are deleted. - An add-on could use translate operator to move something it controls, related to vertices positions. ## Benefits - Addon's are not abusing on timers - Code if more event focused ## Desing ![desing](https://tornavis.org/mblender_patches/patches/mb-0011-operator-handlers.svg) ## Python example code ```Py import bpy #custom bpy operators class SimpleOperator(bpy.types.Operator): """Tooltip""" bl_idname = "object.simple_operator" bl_label = "Simple Object Operator" @classmethod def poll(cls, context): return context.active_object is not None def execute(self, context): return {'FINISHED'} bpy.utils.register_class(SimpleOperator) # Any Python object can act as the handler owner. owner = object() # Poll def handler_poll_true(context, event, params): return True def handler_poll_false(context, event, params): return False def handler_poll(context, event, params, arg): return arg == True # Callbacks def pre_invoke_callback(context, event, params): print("[PRE] invoke", params) def post_invoke_callback(context, event, params, ret_code): print("[POST] invoke", params, "returned", ret_code) def pre_invoke_callback_owner(context, event, params): print("[PRE] invoke (with owner)", params) def post_invoke_callback_owner(context, event, params, ret_code): print("[POST] invoke (with owner)", params, "returned", ret_code) def pre_invoke_callback_args(context, event, params, args): print("[PRE] invoke args", args, params) def post_invoke_callback_args(context, event, params, ret_code, args): print("[POST] invoke args", params, "returned", ret_code, "args", args) def pre_invoke_callback_owner_args(context, event, params, args): print("[PRE] invoke (with owner) args:", args, params) def post_invoke_callback_owner_args(ctx, evt, params, ret_code, args): print("[POST] invoke (with owner)", params , "returned", ret_code, "args:", args) def pre_invoke_callback_override(context, event, params): print ("Overrided") return False def modal_callback(context, event, params, ret_code): print (context.active_object) print (event) print ("modal") def modal_callback_args(context, event, params, ret_code, args): print (context.active_object) print (event.mouse_x, event.mouse_y) print ("modal", args) def modal_end_callback(context, event, params, ret_code): print("modal end", ret_code) def pre_invoke_custom_op_callback(context, event, params): print("[PRE] invoke custom operator", params ) def post_invoke_custom_op_callback(context, event, params, ret_code): print("[POST] invoke custom operator", params, ret_code) # Registration bpy.ops.mesh.primitive_cube_add.handlers.invoke_pre.append(pre_invoke_callback) bpy.ops.mesh.primitive_cube_add.handlers.invoke_post.append(post_invoke_callback) bpy.ops.mesh.primitive_cube_add.handlers.invoke_pre.append(cb=pre_invoke_callback_args, poll = handler_poll, args=(False,)) bpy.ops.mesh.primitive_cube_add.handlers.invoke_post.append(cb=post_invoke_callback_args, args=(1,)) bpy.ops.mesh.primitive_cube_add.handlers.invoke_pre.append(pre_invoke_callback_owner, owner) bpy.ops.mesh.primitive_cube_add.handlers.invoke_post.append(post_invoke_callback_owner, owner) bpy.ops.mesh.primitive_cube_add.handlers.invoke_pre.append(pre_invoke_callback_owner_args, owner,(1,)) bpy.ops.mesh.primitive_cube_add.handlers.invoke_post.append(post_invoke_callback_owner_args, owner,(1,)) bpy.ops.object.simple_operator.handlers.invoke_pre.append(pre_invoke_custom_op_callback) bpy.ops.object.simple_operator.handlers.invoke_post.append(post_invoke_custom_op_callback) #Showing the splash will not print "overrided" and do anything bpy.ops.wm.splash.handlers.invoke_pre.append(pre_invoke_callback_override) # Unregistration # Remove one handler from pre_invoke bpy.ops.mesh.primitive_cube_add.handlers.invoke_pre.remove(pre_invoke_callback) #remove all handlers from post_invoke owned bpy.ops.mesh.primitive_cube_add.handlers.invoke_post.remove(owner=owner) # Remove all handlers owned bpy.ops.remove_handlers(owner=owner) # calling the MESH_OT_primitive_cube_add operator should output """ [POST] invoke {'size': 2.0, 'calc_uvs': False, 'enter_editmode': True, 'align': 0, 'location': (0.0, 0.0, 0.0), 'rotation': (0.0, 0.0, 0.0), 'scale': (1.0, 1.0, 1.0)} returned {'FINISHED'} [POST] invoke args {'size': 2.0, 'calc_uvs': False, 'enter_editmode': True, 'align': 0, 'location': (0.0, 0.0, 0.0), 'rotation': (0.0, 0.0, 0.0), 'scale': (1.0, 1.0, 1.0)} returned {'FINISHED'} args 1 """ # calling the OBJECT_OT_simple_operator() # bpy.ops.object.simple_operator() """ [PRE] invoke custom operator {} [POST] invoke custom operator {'FINISHED'} """ bpy.ops.transform.translate.handlers.modal.append(cb = modal_callback_args, args = (1,)) bpy.ops.transform.translate.handlers.modal.append(cb= modal_callback, poll = handler_poll_false) bpy.ops.transform.translate.handlers.modal_end.append(modal_end_callback) # Moving an object should output """ <bpy_struct, Object("Cube.001") at 0x0000028E8F0D7E08> 246 572 modal 1 ... modal end {'FINISHED'} """ def selection_cb(context, event, params,ret): print("SELECT", params, ret) bpy.ops.view3d.select.handlers.invoke_post.append(selection_cb) # Click on 3D view should output """ SELECT {'extend': True, 'deselect': True, 'toggle': True, 'deselect_all': False, 'center': True, 'enumerate': True, 'object': True, 'location': (222, 123)} {'PASS_THROUGH', 'FINISHED'} """ ``` ## More This was previously submitted on phabricator [D10579](https://archive.blender.org/developer/D10579) and

👍 4 👀 3 ❤️ 4

Jaume Bellet added 1 commit 2024-02-06 18:32:35 +01:00

7908e90d29 Adds operator handlers to operators.

Allows executing python code pre and post execution.

Iliya Katushenock added this to the Python API project 2024-02-06 18:34:56 +01:00

Jaume Bellet added 1 commit 2024-02-06 20:42:00 +01:00

5cc4c29784 missing files to be added on previous commit

Ted Milker commented

2024-02-08 02:11:54 +01:00

First-time contributor

This doesn't perfectly match the handler behavior I'd like to see for switching to/from a WorkSpaceTool but it's better than a timer that I currently have to use. I hope this is merged.

Jaume Bellet commented

2024-02-12 06:45:39 +01:00

First-time contributor

#118026 allows to set callbacks on WorkspaceTool set / unset.

It should also be possible using the handlers introduced on this PR, using it over tool_set_by_id operator. On PRE , the current Tool is the previous tool, and on POST, the current tool is the one user has been selected, which should match the operator parameters.

#118026 allows to set callbacks on WorkspaceTool set / unset. It should also be possible using the handlers introduced on this PR, using it over tool_set_by_id operator. On PRE , the current Tool is the previous tool, and on POST, the current tool is the one user has been selected, which should match the operator parameters.

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git fetch -u pr-0011-operator-handlers:JaumeBellet-pr-0011-operator-handlers

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Adds operator handlers to operators. #117912

Motivation

Usage examples

Benefits

Desing

Python example code

More

Checkout