Enum EarlyDepthTest 

pub enum EarlyDepthTest {
    Force,
    Allow {
        conservative: ConservativeDepth,
    },
}

Available on crate feature unstable-wgpu-27 only.

Explicitly allows early depth/stencil tests.

Normally, depth/stencil tests are performed after fragment shading. However, as an optimization, most drivers will move the depth/stencil tests before fragment shading if this does not have any observable consequences. This optimization is disabled under the following circumstances:

• discard is called in the fragment shader.
• The fragment shader writes to the depth buffer.
• The fragment shader writes to any storage bindings.

When EarlyDepthTest is set, it is allowed to perform an early depth/stencil test even if the above conditions are not met. When EarlyDepthTest::Force is used, depth/stencil tests must be performed before fragment shading.

To force early depth/stencil tests in a shader:

• GLSL: layout(early_fragment_tests) in;
• HLSL: Attribute earlydepthstencil
• SPIR-V: ExecutionMode EarlyFragmentTests
• WGSL: @early_depth_test(force)

This may also be enabled in a shader by specifying a ConservativeDepth.

For more, see:

• https://www.khronos.org/opengl/wiki/Early_Fragment_Test#Explicit_specification
• https://docs.microsoft.com/en-us/windows/win32/direct3dhlsl/sm5-attributes-earlydepthstencil
• https://www.khronos.org/registry/SPIR-V/specs/unified1/SPIRV.html#Execution_Mode

Variants

Force

Requires depth/stencil tests to be performed before fragment shading.

This will disable depth/stencil tests after fragment shading, so discarding the fragment or overwriting the fragment depth will have no effect.

Allow

Allows an additional depth/stencil test to be performed before fragment shading.

It is up to the driver to decide whether early tests are performed. Unlike Force, this does not disable depth/stencil tests after fragment shading.

Fields

conservative: ConservativeDepth

Specifies restrictions on how the depth value can be modified within the fragment shader.

This may be taken into account when deciding whether to perform early tests.

Trait Implementations

impl Clone for EarlyDepthTest

fn clone(&self) -> EarlyDepthTest

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for EarlyDepthTest

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

Formats the value using the given formatter.

impl Hash for EarlyDepthTest

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

where __H: Hasher,

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 Ord for EarlyDepthTest

fn cmp(&self, other: &EarlyDepthTest) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Self

where Self: Sized,

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Self

where Self: Sized,

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Self

where Self: Sized,

Restrict a value to a certain interval.

impl PartialEq for EarlyDepthTest

fn eq(&self, other: &EarlyDepthTest) -> 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 PartialOrd for EarlyDepthTest

fn partial_cmp(&self, other: &EarlyDepthTest) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

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

Tests less than (for self and other) and is used by the < operator.

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

Tests less than or equal to (for self and other) and is used by the <= operator.

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

Tests greater than (for self and other) and is used by the > operator.

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

Tests greater than or equal to (for self and other) and is used by the >= operator.

impl Copy for EarlyDepthTest

impl Eq for EarlyDepthTest

impl StructuralPartialEq for EarlyDepthTest