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/// Use to declare a new render feature that can be registered. Registration allows easy global
/// access to the render feature index from anywhere in the binary
///
/// Use like this:
///      rafx::declare_render_feature!(Debug3DRenderFeature, DEBUG_3D_RENDER_FEATURE);
///
/// The first name is all that really matters, the second name just needs to be a constant that is
/// exposed via the first name (i.e. Debug3DRenderFeature::feature_index())
///
/// This macro will also define the following helper functions in the same scope.
/// - `render_feature_index()`: Syntactic sugar for Debug3DRenderFeature::feature_index().
/// - `render_feature_debug_name()`: Syntactic sugar for Debug3DRenderFeature::feature_debug_name().
/// - `RenderFeatureType`: Syntactic sugar for Debug3DRenderFeature.
/// - `EXTRACT_SCOPE_NAME`: Syntactic sugar for `&'static str` in the form `Debug3DRenderFeature extract`.
/// - `[...]_SCOPE_NAME`: The same as `EXTRACT_SCOPE_NAME` for other supported job entry points.
#[macro_export]
macro_rules! declare_render_feature {
    ($struct_name:ident, $atomic_constant_name:ident) => {
        static $atomic_constant_name: std::sync::atomic::AtomicI32 =
            std::sync::atomic::AtomicI32::new(-1);

        #[rustfmt::skip]
        static EXTRACT_SCOPE_NAME: &'static str = stringify!($struct_name extract);

        #[rustfmt::skip]
        static PREPARE_SCOPE_NAME: &'static str = stringify!($struct_name prepare);

        #[rustfmt::skip]
        static ON_BEGIN_EXECUTE_GRAPH_SCOPE_NAME: &'static str = stringify!($struct_name on_begin_execute_graph);
        static RENDER_ELEMENT_SCOPE_NAME: &'static str = stringify!($struct_name render_element);
        static APPLY_SETUP_SCOPE_NAME: &'static str = stringify!($struct_name apply_setup);
        static REVERT_SETUP_SCOPE_NAME: &'static str = stringify!($struct_name revert_setup);

        pub struct $struct_name;

        impl RenderFeature for $struct_name {
            fn set_feature_index(index: RenderFeatureIndex) {
                $atomic_constant_name.store(
                    index.try_into().unwrap(),
                    std::sync::atomic::Ordering::Release,
                );
            }

            fn feature_index() -> RenderFeatureIndex {
                $atomic_constant_name.load(std::sync::atomic::Ordering::Acquire)
                    as RenderFeatureIndex
            }

            fn feature_debug_name() -> &'static str {
                stringify!($struct_name)
            }
        }

        fn render_feature_index() -> RenderFeatureIndex {
            $struct_name::feature_index()
        }

        fn render_feature_debug_name() -> &'static str {
            $struct_name::feature_debug_name()
        }
    };
}