Bevy Convars

This is a crate that provides an implementation of Convars (console variables or config variables depending on who you ask), provided as bevy resources, with support for serialization, change detection, and the works. Convars are presented as resources within the Bevy world, and can be accessed as such without any special code.

crate::cvar_collection! {
    pub struct RenderCVars & RenderCVarsMut {
        enable_xr = cvar EnableXr("render.enable_xr", CVarFlags::SAVED): bool = false,
        enable_renderdoc = cvar EnableRenderdoc("render.enable_renderdoc", CVarFlags::LOCAL): bool = false,

        /*
        *   Anti-aliasing
        */
        aa_method = cvar AaMethod("render.aa.method", CVarFlags::SAVED | CVarFlags::RUNTIME): AntialiasMethod = AntialiasMethod::Fxaa,

        fxaa_sensitivity = cvar FxaaSensitivty("render.aa.fxaa_sensitivity", CVarFlags::SAVED | CVarFlags::RUNTIME): FxaaSensitivity = FxaaSensitivity::Medium,

        msaa_samples = cvar MsaaSamples("render.aa.msaa_samples", CVarFlags::SAVED | CVarFlags::RUNTIME): MsaaSamplingConfig = MsaaSamplingConfig::Msaa4,

        /*
        *   SSAO.
        */
        enable_ssao = cvar EnableSsao("render.ssao.enabled", CVarFlags::SAVED | CVarFlags::RUNTIME): bool = true,
        ssao_quality = cvar RenderSsaoQuality("render.ssao.quality", CVarFlags::SAVED | CVarFlags::RUNTIME): SsaoQuality = SsaoQuality::High,
        ssao_object_thickness = cvar SsaoObjectThickness("render.ssao.object_thickness", CVarFlags::SAVED | CVarFlags::RUNTIME): f32 = 0.25
    }

    pub struct RenderCVarsPlugin;
}

 ...

fn sync_cvars_to_camera(
   cameras: Query<(Entity, Ref<SettingsAwareCamera>)>,
   cvars: RenderCVars,
   enable_ssao: Res<EnableSsao>,
   mut commands: Commands,
) {
   // Can read directly out of the RenderCVars param..
   let aa_method = **cvars.aa_method;

   // or from a specific cvar resource.
   // All CVar types implement Deref and DerefMut for their inner type to make them easy to unpack and modify.
   let ssao_on = **enable_ssao;

   ...
}

State of Development

This crate is very early, and while it probably can replace your existing solution it needs some elbow grease to use outside of the supported usecases.

• Config loading.
  • Layered configs loading.
  • Builtin system for config presets (can easily be implemented by loading config files containing the preset.)
• Config saving.
• Config reflection.
• Intelligent default value handling.
• Built-in support for existing netcode libraries.
• Full no_std support. (Needs further testing and work)
  • WASM support.
• Minimal set of required Bevy features.

Bevy Compatibility

This library tracks Bevy's releases, at this time the following holds:

License

This work is available under EITHER the Apache 2.0 license (as provided in LICENSE-APACHE) or the MIT license (as provided in LICENSE-MIT).