gamescope is a micro-compositor from Valve that allows running games in
an isolated Wayland compositor session. It supports nested mode (runs
inside an existing desktop) and embedded/kiosk mode (SteamOS-style full
session).

Features include:
 - Resolution scaling and upscaling (AMD FSR, NIS)
 - HDR support
 - Frame limiting and VRR/FreeSync support
 - Vulkan-based compositing
 - Screen capture via PipeWire

This build clones the source repository and initializes submodules at
build time, as the upstream bundled dependencies (wlroots, libliftoff,
vkroots) must be built from specific pinned commits.

Requirements:
 - git (to clone and initialize submodules at build time)
 - meson >= 0.58.0
 - ninja
 - Vulkan SDK / vulkan-headers / vulkan-loader
 - wayland (in Slackware base)
 - libX11 (in Slackware base)
 - SDL2 (in Slackware base)
 - pipewire (in Slackware base)
 - libei (in Slackware base)

SBo dependencies:
 - libavif (for AVIF screenshot support)

Optional: OpenVR support is auto-detected if the openvr library is
present.

Graphics support:
 - AMD: Mesa 20.3+ (GFX9+); for GFX8 and older set R600_DEBUG=nodcc
 - Intel: Mesa 21.2+
 - NVIDIA: proprietary 515.43.04+ with nvidia-drm.modeset=1 kernel
   parameter