Does reading proprietary artwork in the source code violate GPLv3 license?

Question

Just out of curiosity, if I make a GPLv3 software that have source code that tell the program to read a file that is a proprietary artwork, but this artwork is not included in my project, does that violate GPLv3 license?

For example, I made a game project that look like this:

folder:My Game
file:main.py

# Copyright (C) 2023 My Name
# SPDX-License-Identifier: GPL-3.0-or-later

import os

if os.path.isfile("proprietary_artwork_package/game_conversation.txt"):
    print("Thank you for buying the artwork package! Enjoy!")
    f = open("proprietary_artwork_package/game_conversation.txt")
    print(f.read())
    f.close()
else:
    print(
        "Please buy the artwork of my game at https://www.some-membership-platform.com/my-support-page.html, extract it at the game folder to get the full gaming experience!"
    )
print("\n\nThe end.\n\n\nCredit:\n\tAAA\n\tBBB\n\tCCC\n")
print("GPLv3 License stuff.")

file: license.txt

<content of GPLv3 license>

Does this game project violate GPLv3 license?

Answer 1

That's fine.

Artwork and code are different things, and they can exist and be distributed independently.

The open source version of a number of games are example of these kind of behaviour (e.g. OpenTTD, OpenDune, CorsixTH, etc) as are the converse relation with free and sometimes open source fan modpacks for proprietary games.

Usually the graphics need to be supplied in a well-defined format to be interpreted correctly by the programme (and which has to be documented to at least some degree) and thus there exists a public API by which they communicate with (or are 'digested' by) the programme.