Struct ExternalRuns 

pub struct ExternalRuns { /* private fields */ }

The distinct external textures one frame draws with, in the order it first names them.

A frame’s instances are drawn in painter order, and the single external binding has to be re-set whenever that order crosses from one texture to another. Rather than carry the id on every instance, each encoded paint takes a slot — its index here — and the renderer’s pass segments carry that slot, so a run of instances sharing a texture is one segment and one bind-group set.

Filled while the frame’s paints are lowered and read while its passes are recorded; cleared and refilled per frame, never growing past the number of external textures a single frame draws.

Implementations

impl ExternalRuns

pub fn new() -> Self

An empty set of runs.

pub fn clear(&mut self)

Forgets the previous frame’s textures, keeping the allocation.

pub fn slot_of(&mut self, key: u64) -> Option<u32>

The slot key is drawn under, assigning one if this frame has not named it yet.

A linear scan rather than a map: a frame draws a handful of external textures at most — the binding is re-set between runs, so a scene that interleaved hundreds would be paying far more for the pass breaks than for the lookup.

None once the slot numbering would leave u32, which no real frame reaches; the paint is then left unresolved and its draws skipped, which is the same answer an unbound texture gets.

pub fn keys(&self) -> &[u64]

The texture each slot names, indexed by slot number.

pub fn key_at(&self, slot: u32) -> Option<u64>

The texture drawn under slot.

pub fn len(&self) -> usize

How many distinct external textures the frame draws.

pub fn is_empty(&self) -> bool

Whether the frame draws none.

Trait Implementations

impl Debug for ExternalRuns

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

Formats the value using the given formatter.

impl Default for ExternalRuns

fn default() -> Self

Returns the “default value” for a type.