Enum Binding 

pub enum Binding {
    BuiltIn(BuiltIn),
    Location {
        location: u32,
        interpolation: Option<Interpolation>,
        sampling: Option<Sampling>,
        blend_src: Option<u32>,
        per_primitive: bool,
    },
}

Describes how an input/output variable is to be bound.

Variants

BuiltIn(BuiltIn)

Built-in shader variable.

Location

Indexed location.

This is a value passed to a Fragment shader from a Vertex or Mesh shader.

Values passed from the Vertex stage to the Fragment stage must have their interpolation defaulted (i.e. not None) by the front end as appropriate for that language.

For other stages, we permit interpolations even though they’re ignored. When a front end is parsing a struct type, it usually doesn’t know what stages will be using it for IO, so it’s easiest if it can apply the defaults to anything with a Location binding, just in case.

For anything other than floating-point scalars and vectors, the interpolation must be Flat.

Fields

location: u32

interpolation: Option<Interpolation>

sampling: Option<Sampling>

blend_src: Option<u32>

Optional blend_src index used for dual source blending. See https://www.w3.org/TR/WGSL/#attribute-blend_src

per_primitive: bool

Whether the binding is a per-primitive binding for use with mesh shaders.

This must be true if this binding is a mesh shader primitive output, or such an output’s corresponding fragment shader input. It must be false otherwise.

A stage’s outputs must all have unique location numbers, regardless of whether they are per-primitive; a mesh shader’s per-vertex and per-primitive outputs share the same location numbering space.

Per-primitive values are not interpolated at all and are not dependent on the vertices or pixel location. For example, it may be used to store a non-interpolated normal vector.

Implementations

impl Binding

pub(crate) fn apply_default_interpolation(&mut self, ty: &TypeInner)

Apply default interpolation (if applicable) for ty to the binding.

This function is a utility front ends may use to satisfy the Naga IR’s requirement, meant to ensure that input languages’ policies have been applied appropriately, that all I/O Bindings from the vertex shader to the fragment shader must have non-None interpolation values.

All the shader languages Naga supports have similar rules: perspective-correct, center-sampled interpolation is the default for any binding that can vary, and an explicit flat qualifier/attribute/what-have-you is required for bindings that cannot.

• If binding is not a Location binding, or if its interpolation is already set, then this function makes no changes.

• If ty is a floating-point scalar, vector, or matrix type, then apply the default Perspective interpolation and Center sampling.

• If ty is an integral scalar or vector, make no changes; if the interpolation was None, it will remain so, and be rejected by the validator.

For struct types, the bindings are defined on the members, so there is nothing to adjust on the struct itself.

Other non-struct types are not permitted as user-defined IO values, and will be rejected by the validator.

impl Binding

pub const fn to_built_in(&self) -> Option<BuiltIn>

Trait Implementations

impl<'arbitrary> Arbitrary<'arbitrary> for Binding

fn arbitrary(u: &mut Unstructured<'arbitrary>) -> Result<Self>

Generate an arbitrary value of Self from the given unstructured data.

fn arbitrary_take_rest(u: Unstructured<'arbitrary>) -> Result<Self>

Generate an arbitrary value of Self from the entirety of the given unstructured data.

fn size_hint(depth: usize) -> (usize, Option<usize>)

Get a size hint for how many bytes out of an Unstructured this type needs to construct itself.

fn try_size_hint( depth: usize, ) -> Result<(usize, Option<usize>), MaxRecursionReached>

Get a size hint for how many bytes out of an Unstructured this type needs to construct itself.

impl Clone for Binding

fn clone(&self) -> Binding

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Binding

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for Binding

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Hash for Binding

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl PartialEq for Binding

fn eq(&self, other: &Binding) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Serialize for Binding

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl Eq for Binding

impl StructuralPartialEq for Binding