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Blender integration

Run python script at launch​

In case you need to execute a python script when Blender is started (aka -P), for example to programmatically modify a blender file for conformation, you can create an OpenPype hook as follows:

from openpype.hosts.blender.hooks import pre_add_run_python_script_arg
from openpype.lib import PreLaunchHook


class MyHook(PreLaunchHook):
    """Add python script to be executed before Blender launch."""

    order = pre_add_run_python_script_arg.AddPythonScriptToLaunchArgs.order - 1
    app_groups = [
        "blender",
    ]

    def execute(self):
        self.launch_context.data.setdefault("python_scripts", []).append(
            "/path/to/my_script.py"
        )

You can write a bare python script, as you could run into the Text Editor.

Python script with arguments​

Adding arguments​

In case you need to pass arguments to your script, you can append them to self.launch_context.data["script_args"]:

self.launch_context.data.setdefault("script_args", []).append(
        "--my-arg",
        "value",
    )

Parsing arguments​

You can parse arguments in your script using argparse as follows:

import argparse

parser = argparse.ArgumentParser(
    description="Parsing arguments for my_script.py"
)
parser.add_argument(
    "--my-arg",
    nargs="?",
    help="My argument",
)
args, unknown = arg_parser.parse_known_args(
    sys.argv[sys.argv.index("--") + 1 :]
)
print(args.my_arg)