Gamescope

gamescope --help 
usage: gamescope [options...] -- [command...] 

Options: 
 --help                         show help message 
 -W, --output-width             output width 
 -H, --output-height            output height 
 -w, --nested-width             game width 
 -h, --nested-height            game height 
 -r, --nested-refresh           game refresh rate (frames per second) 
 -m, --max-scale                maximum scale factor 
 -S, --scaler                   upscaler type (auto, integer, fit, fill, stretch) 
 -F, --filter                   upscaler filter (linear, nearest, fsr, nis, pixel) 
                                    fsr => AMD FidelityFX™ Super Resolution 1.0 
                                    nis => NVIDIA Image Scaling v1.0.3 
 --sharpness, --fsr-sharpness   upscaler sharpness from 0 (max) to 20 (min) 
 --expose-wayland               support wayland clients using xdg-shell 
 --headless                     use headless backend (no window, no DRM output) 
 --cursor                       path to default cursor image 
 -R, --ready-fd                 notify FD when ready 
 --rt                           Use realtime scheduling 
 -T, --stats-path               write statistics to path 
 -C, --hide-cursor-delay        hide cursor image after delay 
 -e, --steam                    enable Steam integration 
 --xwayland-count               create N xwayland servers 
 --prefer-vk-device             prefer Vulkan device for compositing (ex: 1002:7300) 
 --force-orientation            rotate the internal display (left, right, normal, upsidedown) 
 --force-windows-fullscreen     force windows inside of gamescope to be the size of the nested display (fullscreen) 
 --cursor-scale-height          if specified, sets a base output height to linearly scale the cursor against. 
 --hdr-enabled                  enable HDR output (needs Gamescope WSI layer enabled for support from clients) 
                                If this is not set, and there is a HDR client, it will be tonemapped SDR. 
 --sdr-gamut-wideness           Set the 'wideness' of the gamut for SDR comment. 0 - 1. 
 --hdr-sdr-content-nits         set the luminance of SDR content in nits. Default: 400 nits. 
 --hdr-itm-enable               enable SDR->HDR inverse tone mapping. only works for SDR input. 
 --hdr-itm-sdr-nits             set the luminance of SDR content in nits used as the input for the inverse tone mapping process. 
                                Default: 100 nits, Max: 1000 nits 
 --hdr-itm-target-nits          set the target luminace of the inverse tone mapping process. 
                                Default: 1000 nits, Max: 10000 nits 
 --framerate-limit              Set a simple framerate limit. Used as a divisor of the refresh rate, rounds down eg 60 / 59 -> 60fps, 60 / 25 -> 30fps. Default: 0, disabled. 

Nested mode options: 
 -o, --nested-unfocused-refresh game refresh rate when unfocused 
 -b, --borderless               make the window borderless 
 -f, --fullscreen               make the window fullscreen 
 -g, --grab                     grab the keyboard 
 --force-grab-cursor            always use relative mouse mode instead of flipping dependent on cursor visibility. 

Embedded mode options: 
 -O, --prefer-output            list of connectors in order of preference 
 --default-touch-mode           0: hover, 1: left, 2: right, 3: middle, 4: passthrough 
 --generate-drm-mode            DRM mode generation algorithm (cvt, fixed) 
 --immediate-flips              Enable immediate flips, may result in tearing 
 --adaptive-sync                Enable adaptive sync if available (variable rate refresh) 

VR mode options: 
 --openvr                                 Uses the openvr backend and outputs as a VR overlay 
 --vr-overlay-key                         Sets the SteamVR overlay key to this string 
 --vr-overlay-explicit-name               Force the SteamVR overlay name to always be this string 
 --vr-overlay-default-name                Sets the fallback SteamVR overlay name when there is no window title 
 --vr-overlay-icon                        Sets the SteamVR overlay icon to this file 
 --vr-overlay-show-immediately            Makes our VR overlay take focus immediately 
 --vr-overlay-enable-control-bar          Enables the SteamVR control bar 
 --vr-overlay-enable-control-bar-keyboard Enables the SteamVR keyboard button on the control bar 
 --vr-overlay-enable-control-bar-close    Enables the SteamVR close button on the control bar 
 --vr-overlay-modal                       Makes our VR overlay appear as a modal 
 --vr-overlay-physical-width              Sets the physical width of our VR overlay in metres 
 --vr-overlay-physical-curvature          Sets the curvature of our VR overlay 
 --vr-overlay-physical-pre-curve-pitch    Sets the pre-curve pitch of our VR overlay 
 --vr-scrolls-speed                       Mouse scrolling speed of trackpad scroll in VR. Default: 8.0 

Debug options: 
 --disable-layers               disable libliftoff (hardware planes) 
 --debug-layers                 debug libliftoff 
 --debug-focus                  debug XWM focus 
 --synchronous-x11              force X11 connection synchronization 
 --debug-hud                    paint HUD with debug info 
 --debug-events                 debug X11 events 
 --force-composition            disable direct scan-out 
 --composite-debug              draw frame markers on alternating corners of the screen when compositing 
 --disable-color-management     disable color management 
 --disable-xres                 disable XRes for PID lookup 
 --hdr-debug-force-support      forces support for HDR, etc even if the display doesn't support it. HDR clients will be outputted as SDR still in that case. 
 --hdr-debug-force-output       forces support and output to HDR10 PQ even if the output does not support it (will look very wrong if it doesn't) 
 --hdr-debug-heatmap            displays a heatmap-style debug view of HDR luminence across the scene in nits. 
Reshade shader options: 
 --reshade-effect               sets the name of a reshade shader to use in either /usr/share/gamescope/reshade/Shaders or ~/.local/share/gamescope/reshade/Shaders 
 --reshade-technique-idx        sets technique idx to use from the reshade effect 

Steam Deck options: 
 --mura-map                     Set the mura compensation map to use for the display. Takes in a path to the mura map. 

Keyboard shortcuts: 
 Super + F                      toggle fullscreen 
 Super + N                      toggle nearest neighbour filtering 
 Super + U                      toggle FSR upscaling 
 Super + Y                      toggle NIS upscaling 
 Super + I                      increase FSR sharpness by 1 
 Super + O                      decrease FSR sharpness by 1 
 Super + S                      take a screenshot 
 Super + G                      toggle keyboard grab