Struct PhaseItemExtraIndex

pub struct PhaseItemExtraIndex(pub u32);

The “extra index” associated with some PhaseItems, alongside the indirect instance index.

Sometimes phase items require another index in addition to the range of instances they already have. These can be:

• The dynamic offset: a wgpu dynamic offset into the uniform buffer of instance data. This is used on platforms that don’t support storage buffers, to work around uniform buffer size limitations.

• The indirect parameters index: an index into the buffer that specifies the indirect parameters for this PhaseItem’s drawcall. This is used when indirect mode is on (as used for GPU culling).

Note that our indirect draw functionality requires storage buffers, so it’s impossible to have both a dynamic offset and an indirect parameters index. This convenient fact allows us to pack both indices into a single u32.

Tuple Fields

0: u32

Implementations

impl PhaseItemExtraIndex

pub const INDIRECT_PARAMETER_INDEX: u32 = 2_147_483_648u32

The flag that indicates that this index is an indirect parameter. If not set, this is a dynamic offset.

pub const OFFSET_MASK: u32 = 2_147_483_647u32

To extract the index from a packed PhaseItemExtraIndex, bitwise-and the contents with this value.

pub const FLAGS_MASK: u32 = 2_147_483_648u32

To extract the flag from a packed PhaseItemExtraIndex, bitwise-and the contents with this value.

pub const NONE: PhaseItemExtraIndex = _

The special value that indicates that no extra index is present.

pub fn indirect_parameters_index( indirect_parameter_index: u32, ) -> PhaseItemExtraIndex

Packs a indirect parameters index into this extra index.

pub fn maybe_indirect_parameters_index( maybe_indirect_parameters_index: Option<NonMaxU32>, ) -> PhaseItemExtraIndex

Returns either an indirect parameters index or PhaseItemExtraIndex::NONE, as appropriate.

pub fn dynamic_offset(dynamic_offset: u32) -> PhaseItemExtraIndex

Packs a dynamic offset into this extra index.

pub fn maybe_dynamic_offset( maybe_dynamic_offset: Option<NonMaxU32>, ) -> PhaseItemExtraIndex

Returns either a dynamic offset or PhaseItemExtraIndex::NONE, as appropriate.

pub fn as_dynamic_offset(&self) -> Option<NonMaxU32>

If this extra index describes a dynamic offset, returns it; otherwise, returns None.

pub fn as_indirect_parameters_index(&self) -> Option<u32>

If this extra index describes an indirect parameters index, returns it; otherwise, returns None.

Trait Implementations

impl Clone for PhaseItemExtraIndex

fn clone(&self) -> PhaseItemExtraIndex

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for PhaseItemExtraIndex

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

Formats the value using the given formatter.

impl Hash for PhaseItemExtraIndex

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 PhaseItemExtraIndex

fn eq(&self, other: &PhaseItemExtraIndex) -> 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 Copy for PhaseItemExtraIndex

impl Eq for PhaseItemExtraIndex

impl StructuralPartialEq for PhaseItemExtraIndex