Unlinked Copy Add-In Issues

[carson_akasper]

Hey everyone,

I'm developing a custom Add-In that creates true, independent copies of components within the same Fusion file. Unlike the standard copy-paste, which creates linked references, this Add-In exports the selected component as an .f3d file and then re-imports it, resulting in a fully unlinked, stand-alone copy.

However, I’ve run into a strange issue that I can best explain with an example:

I start with Part 1 and create an unlinked copy of it using my Add-In. I then create a joint between the original and the copy. Next, I make a new component called "Component A" and move both Part 1 and its unlinked copy into it. Then, I make an unlinked copy of Component A—this becomes "Component B." When I create a joint between Components A and B, things start to get weird. The internal joint in Component B appears to "split"—the blue half of the joint icon stays with a group of three parts, while the white half is left behind with the separate part. They should be connected, but they’re not. As soon as I move one of the parts, the separated part snaps back into place and the joint appears correct again.

However, when I then create another new component ("Component C") and move Components A and B into it, that same internal joint from Component B completely loses its references. The joint still exists, but it's no longer connected to either part—it just floats in space. So it seems like whenever an unlinked copy containing joints is reparented, those joints behave unpredictably—sometimes not updating immediately, and eventually losing their references entirely.

I'm wondering if anyone has insight into why this happens or how I might be able to address it programmatically.

[carson_akasper]

This is my first time trying to write a program for fusion, so ChatGPT carried me through this bit, but I think I'm starting to grasp the concepts. Here is my code. I have three files: an Initialize file that has almost nothing in it, it just tells it to run, and then an entry file and an operation file. It's all in Python.

Entry file:

import adsk.core

import adsk.fusion

import os

from ...lib import fusionAddInUtils as futil

from ... import config

from . import operation

app = adsk.core.Application.get()

ui = app.userInterface

# Unique command ID and metadata

CMD_ID = 'unlinkedCopy'

CMD_NAME = 'Unlinked Copy'

CMD_DESCRIPTION = 'Creates unlinked copies of the selected components'

IS_PROMOTED = True

# Panel was created in commands/__init__.py

WORKSPACE_ID = 'FusionSolidEnvironment'

PANEL_ID = 'ExpandedAssemblyPanel'

COMMAND_BESIDE_ID = 'ScriptsManagerCommand'

ICON_FOLDER = os.path.join(os.path.dirname(__file__), 'resources', '')

# Local list to prevent garbage collection

local_handlers = []

def start():

    try:

        cmd_def = ui.commandDefinitions.itemById(CMD_ID)

        if cmd_def:

            cmd_def.deleteMe()

        cmd_def = ui.commandDefinitions.addButtonDefinition(

            CMD_ID, CMD_NAME, CMD_DESCRIPTION, ICON_FOLDER

        )

        futil.add_handler(cmd_def.commandCreated, command_created)

        panel = ui.allToolbarPanels.itemById(PANEL_ID)

        if panel and not panel.controls.itemById(CMD_ID😞

            control = panel.controls.addCommand(cmd_def, COMMAND_BESIDE_ID, False)

            control.isPromoted = IS_PROMOTED

    except Exception as e:

        futil.handle_error(f'start: {str(e)}')

def stop():

    try:

        panel = ui.allToolbarPanels.itemById(PANEL_ID)

        if panel:

            control = panel.controls.itemById(CMD_ID)

            if control:

                control.deleteMe()

        cmd_def = ui.commandDefinitions.itemById(CMD_ID)

        if cmd_def:

            cmd_def.deleteMe()

    except Exception as e:

        futil.handle_error(f'stop: {str(e)}')

def command_created(args: adsk.core.CommandCreatedEventArgs😞

    futil.log(f'{CMD_NAME} Command Created')

    command = args.command

    inputs = command.commandInputs

    # Selection input (allow multiple components to be selected)

    select_input = inputs.addSelectionInput(

        'target_components',

        'Select Components',

        'Choose the components to copy'

    )

    select_input.addSelectionFilter('Occurrences')

    select_input.setSelectionLimits(1, 0)  # Allow multiple selections

    futil.add_handler(command.execute, command_execute, local_handlers=local_handlers)

    futil.add_handler(command.destroy, command_destroy, local_handlers=local_handlers)

def command_execute(args: adsk.core.CommandEventArgs😞

    # Get the selected occurrences from the command inputs

    command = args.command

    inputs = command.commandInputs

    select_input = inputs.itemById('target_components')

    if not select_input or select_input.selectionCount == 0:

        ui.messageBox('No components selected to copy.')

        return

    # Extract occurrences

    occurrences = [adsk.fusion.Occurrence.cast(select_input.selection(i).entity) for i in range(select_input.selectionCount)]

    # Now call the operation with both arguments

    operation.run_operation(args, occurrences)

def command_destroy(args: adsk.core.CommandEventArgs😞

    futil.log(f'{CMD_NAME} Command Destroyed')

    global local_handlers

    local_handlers = []

Operation file:

import adsk.core

import adsk.fusion

import os

import tempfile

def sanitize_filename(name: str) -> str:

    """Sanitize the component name to remove invalid characters."""

    invalid_chars = '<>:"/\\|?*'

    return ''.join(c for c in name if c not in invalid_chars)

def run_operation(args, occurrences😞

    app = adsk.core.Application.get()

    ui = app.userInterface

    design = adsk.fusion.Design.cast(app.activeProduct)

    root_comp = design.rootComponent

    export_mgr = design.exportManager

    import_mgr = app.importManager

    temp_dir = tempfile.gettempdir()

    for occ in occurrences:

        try:

            # Generate a safe filename

            safe_name = sanitize_filename(occ.component.name + " UC")

            temp_path = os.path.join(temp_dir, f'{safe_name}_temp.f3d')

            # Export the component to an .f3d file

            export_options = export_mgr.createFusionArchiveExportOptions(temp_path, occ.component)

            export_options.isComponentNative = True

            if not export_mgr.execute(export_options😞

                ui.messageBox(f'❌ Failed to export component: {occ.component.name}')

                continue

            if not os.path.exists(temp_path) or os.path.getsize(temp_path) < 1000:

                ui.messageBox(f"⚠ Exported file is missing or invalid for {occ.component.name}: {temp_path}")

                continue

            before_count = root_comp.occurrences.count

            # Import the component back into the root

            import_options = import_mgr.createFusionArchiveImportOptions(temp_path)

            result = import_mgr.importToTarget(import_options, root_comp)

            if not result:

                ui.messageBox(f"❌ Import returned False for {occ.component.name}")

                continue

            # Get the new occurrence

            after_count = root_comp.occurrences.count

            if after_count <= before_count:

                ui.messageBox(f'⚠ Import succeeded but no new component found for {occ.component.name}')

                continue

            new_occ = root_comp.occurrences.item(after_count - 1)

            if new_occ.isReferencedComponent:

                new_occ.breakLink()

            new_occ.component.name = safe_name

            # Cleanup temp file

            if os.path.exists(temp_path😞

                os.remove(temp_path)

        except Exception as e:

            ui.messageBox(f"❌ Error during processing {occ.component.name}:\n{e}")