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use objc2::{Encode, Encoding, RefEncode};
/// Enumerates the different support levels for sparse textures (from `MTLTextureSparseTier`).
#[repr(i64)]
#[derive(Copy, Clone, Debug, Eq, PartialEq, Hash, PartialOrd, Ord)]
pub enum MTLTextureSparseTier {
/// Indicates that the texture is not sparse.
None = 0,
/// Indicates support for sparse textures tier 1.
///
/// Tier 1 sparse textures allow the following:
/// - Partial memory backing at sparse tile granularity.
/// - Defined behavior for accessing an unbacked texture region.
/// - Shader feedback on texture access to determine memory backing.
///
/// An unbacked texture region indicates a region within the texture that doesn't
/// have memory backing at a given point in time. Accessing an unbacked texture
/// region produces the following results:
/// - Reading returns zero (transparent black) for pixel formats with an alpha (A) channel.
/// - Reading returns zero in RGB and one in alpha (A) channels (opaque black) otherwise.
/// - Writing produces no result.
Tier1 = 1,
/// Indicates support for sparse textures tier 2.
///
/// In addition to the guarantees tier 1 sparse textures provide,
/// tier 2 sparse textures allow the following:
/// - Obtain per-tile activity counters.
Tier2 = 2,
}
unsafe impl Encode for MTLTextureSparseTier {
const ENCODING: Encoding = i64::ENCODING;
}
unsafe impl RefEncode for MTLTextureSparseTier {
const ENCODING_REF: Encoding = Encoding::Pointer(&Self::ENCODING);
}