boot.config reference¶

Path templates¶

Some settings accept path templates. A path template is a path that may contain variables in the form $VARNAME.

Supported variables:

$DATE: The local date in YYYY-MM-DD format.
$UTC_DATE: The UTC date in YYYY-MM-DD format.
$TIME: The local time in HH-MM-SS format.
$UTC_TIME: The UTC time in HH-MM-SS format.
$USER_DATA: The user data directory. On Android, this expands to the activity internal data path.
$TMP: The temporary directory.
$RANDOM: An 8-character random string.
$OBB_PATH: Android only. The activity OBB path.

boot_script = "lua/game": Lua script to launch on boot.
boot_package = "boot": Package to load on boot.
render_config = "core/renderer/default": Render configuration to use.
window_title = "My window": Title of the main window on platforms that support it.

All configurations for a given platform are placed under a key named platform. E.g.:

// Linux-only configs
linux = {
  renderer = {
      resolution = [ 1280 720 ]
      aspect_ratio = -1
      vsync = true
  }
}

type = "auto": Sets the renderer backend. Supported values are auto, d3d11, gl, gles and vk.
resolution = [ 1280 720 ]: Sets the width and height of the main window.
aspect_ratio = -1: Sets the aspect ratio. If the value is set to -1, the aspect ratio is computed as width/height of the main window.
vsync = true: Sets whether to enable the vsync.
fullscreen = false: Sets whether to enable fullscreen.
device_id = "0x0000": Sets which GPU to use for rendering. The ID is in hexadecimal notation. Default value selects the first available device.

step_frequency = 60: The frequency at which the physics simulation is stepped. Higher values means a more accurate simulation at the expense of compute time.
max_substeps = 4: Maximum number of physics sub-steps allowed in a frame. A value of 4 at 60 Hz means the physics simulation is allowed to simulate up to ~0.067 seconds (4/60) worth of physics per frame. If one frame takes longer than max_substeps/step_frequency then physics will appear slowed down.
solver_iterations = 10: The number of global solver iterations used for physics constraints. Higher values generally improve stability and joint accuracy at the expense of compute time.
sleep_threshold = 0.5: The default sleeping threshold applied to rigid bodies.

save_dir = $USER_DATA/mygame: Sets the directory where save files will be stored. Setting the save directory is mandatory if you plan to use the SaveGame system.
user_config = $USER_DATA/user.conf: Sets the file where user-specific settings are stored.