Note that Godot comes with a lot of built-in command-line arguments, including several options to specify the window geometry. The editor offers a few more debugging-related arguments too.
Editor options:
Godot Engine v3.1.alpha.custom_build.970b581 - https://godotengine.org
(c) 2007-2018 Juan Linietsky, Ariel Manzur.
(c) 2014-2018 Godot Engine contributors.
Usage: godot [options] [path to scene or 'project.godot' file]
General options:
-h, --help Display this help message.
--version Display the version string.
-v, --verbose Use verbose stdout mode.
--quiet Quiet mode, silences stdout messages. Errors are still displayed.
Run options:
-e, --editor Start the editor instead of running the scene.
-p, --project-manager Start the project manager, even if a project is auto-detected.
-q, --quit Quit after the first iteration.
-l, --language <locale> Use a specific locale (<locale> being a two-letter code).
--path <directory> Path to a project (<directory> must contain a 'project.godot' file).
-u, --upwards Scan folders upwards for project.godot file.
--main-pack <file> Path to a pack (.pck) file to load.
--render-thread <mode> Render thread mode ('unsafe', 'safe', 'separate').
--remote-fs <address> Remote filesystem (<host/IP>[:<port>] address).
--remote-fs-password <password> Password for remote filesystem.
--audio-driver <driver> Audio driver ('PulseAudio', 'ALSA', 'Dummy').
--video-driver <driver> Video driver ('GLES3', 'GLES2').
Display options:
-f, --fullscreen Request fullscreen mode.
-m, --maximized Request a maximized window.
-w, --windowed Request windowed mode.
-t, --always-on-top Request an always-on-top window.
--resolution <W>x<H> Request window resolution.
--position <X>,<Y> Request window position.
--low-dpi Force low-DPI mode (macOS and Windows only).
--no-window Disable window creation (Windows only). Useful together with --script.
Debug options:
-d, --debug Debug (local stdout debugger).
-b, --breakpoints Breakpoint list as source::line comma-separated pairs, no spaces (use %20 instead).
--profiling Enable profiling in the script debugger.
--remote-debug <address> Remote debug (<host/IP>:<port> address).
--debug-collisions Show collisions shapes when running the scene.
--debug-navigation Show navigation polygons when running the scene.
--frame-delay <ms> Simulate high CPU load (delay each frame by <ms> milliseconds).
--time-scale <scale> Force time scale (higher values are faster, 1.0 is normal speed).
--disable-render-loop Disable render loop so rendering only occurs when called explicitly from script.
--disable-crash-handler Disable crash handler when supported by the platform code.
--fixed-fps <fps> Force a fixed number of frames per second. This setting disables real-time synchronization.
--print-fps Print the frames per second to the stdout.
Standalone tools:
-s, --script <script> Run a script.
--check-only Only parse for errors and quit (use with --script).
--export <target> Export the project using the given export target. Export only main pack if path ends with .pck or .zip.
--export-debug <target> Like --export, but use debug template.
--doctool <path> Dump the engine API reference to the given <path> in XML format, merging if existing files are found.
--no-docbase Disallow dumping the base types (used with --doctool).
--build-solutions Build the scripting solutions (e.g. for C# projects).
--gdnative-generate-json-api Generate JSON dump of the Godot API for GDNative bindings.
--test <test> Run a unit test ('string', 'math', 'physics', 'physics_2d', 'render', 'oa_hash_map', 'gui', 'io', 'shaderlang', 'gd_tokenizer', 'gd_parser', 'gd_compiler', 'gd_bytecode', 'image', 'ordered_hash_map', 'astar').
Export template options:
Godot Engine v3.1.alpha.custom_build.f0405d4 - https://godotengine.org
(c) 2007-2018 Juan Linietsky, Ariel Manzur.
(c) 2014-2018 Godot Engine contributors.
Usage: godot-runner [options] [path to scene or 'project.godot' file]
General options:
-h, --help Display this help message.
--version Display the version string.
-v, --verbose Use verbose stdout mode.
--quiet Quiet mode, silences stdout messages. Errors are still displayed.
Run options:
-q, --quit Quit after the first iteration.
-l, --language <locale> Use a specific locale (<locale> being a two-letter code).
--path <directory> Path to a project (<directory> must contain a 'project.godot' file).
-u, --upwards Scan folders upwards for project.godot file.
--main-pack <file> Path to a pack (.pck) file to load.
--render-thread <mode> Render thread mode ('unsafe', 'safe', 'separate').
--remote-fs <address> Remote filesystem (<host/IP>[:<port>] address).
--remote-fs-password <password> Password for remote filesystem.
--audio-driver <driver> Audio driver ('PulseAudio', 'ALSA', 'Dummy').
--video-driver <driver> Video driver ('GLES3', 'GLES2').
Display options:
-f, --fullscreen Request fullscreen mode.
-m, --maximized Request a maximized window.
-w, --windowed Request windowed mode.
-t, --always-on-top Request an always-on-top window.
--resolution <W>x<H> Request window resolution.
--position <X>,<Y> Request window position.
--low-dpi Force low-DPI mode (macOS and Windows only).
--no-window Disable window creation (Windows only). Useful together with --script.
Debug options:
-d, --debug Debug (local stdout debugger).
-b, --breakpoints Breakpoint list as source::line comma-separated pairs, no spaces (use %20 instead).
--profiling Enable profiling in the script debugger.
--remote-debug <address> Remote debug (<host/IP>:<port> address).
--frame-delay <ms> Simulate high CPU load (delay each frame by <ms> milliseconds).
--time-scale <scale> Force time scale (higher values are faster, 1.0 is normal speed).
--disable-render-loop Disable render loop so rendering only occurs when called explicitly from script.
--disable-crash-handler Disable crash handler when supported by the platform code.
--fixed-fps <fps> Force a fixed number of frames per second. This setting disables real-time synchronization.
--print-fps Print the frames per second to the stdout.
Standalone tools:
-s, --script <script> Run a script.
--check-only Only parse for errors and quit (use with --script).
