Support command line arguments to immediately open into a comparison

[0xKZ]

Fixes #44

Proposed changes

• Updated the conda environment name in environment.yml because the windows path as the conda name contain symbols that error on some systems.
• Added an argparse parser (not needed in conda environment since it ships with base python) with 4x arguments.
  • These arguments reflect file paths.
  • The 4x widgets are correspondingly updated with the paths that are provided, if they are provided.
  • If 2 or more paths are provided, a split view is immediately started.

I kept these changes as surgical/minimal as possible to avoid any structural changes to the program. Thankfully it was simple to do.

Originally I attempted directly calling loadFile() but that does not update the other widgets and only creates the split view. Doing it this way by loading via the widgets and then calling the callback as though you pushed the button seems to preserve all the right behaviors.

Testing

I am on a Windows 11 system using MSYS2+bash as the terminal.

(1) Running the program without any arguments

  $ python ./butterfly_viewer/butterfly_viewer.py

This opens the program as before, no images are loaded.

(2) Using one preloaded image

  $ python ./butterfly_viewer/butterfly_viewer.py --image_path_main_topleft butterfly_viewer/icons/icon.png

This opens the viewer with an image in the overlay corner and nothing else:

(3) Using two preloaded images

I have a pink square png in a nearby folder I used for this one:

python ./butterfly_viewer/butterfly_viewer.py --image_path_main_topleft butterfly_viewer/icons/icon.png --image_path_topright ../../../missing_asset_square.png 

This opens the image viewer and it's already in sliding overlay mode. No time wasted! :)

[larsmaxfield]

Great! Nice to see it was straightforward to implement.

Thanks to your code I expanded the args further with these changes:

• Add --paths arg for individual image windows
• Add --hide arg to hide interface --fullscreen arg to go fullscreen
• Rename sliding overlay args to --overlay_path_main_topleft, --overlay_path_topright, etc.