Struct RetainedFrames 

pub struct RetainedFrames { /* private fields */ }

The frame a host presented last, to compare the next with. Where a scene drawn with damage parts (crate::scene_parts) changed is the parts whose commands differ (or what a hinted part says changed); every other pixel is drawn by the same commands as before. Anything that cannot be proven (no parts, a change outside every part, another target) repaints the whole frame.

Implementations

impl RetainedFrames

pub fn repaint( &self, scene: &Scene, parts: Option<&SectionParts>, key: TargetKey, ) -> Repaint

What to repaint of scene, drawn with parts, onto a target that shows the frame last Self::presented.

pub fn presented( &mut self, scene: &Scene, parts: Option<&SectionParts>, key: TargetKey, )

scene, drawn with parts, is what the target with key shows now.

pub fn shows_lost_geometry(&self, scratch: Scratch) -> bool

Whether the renderer’s scratch is scratch without the target having been brought up to date since it changed: a frame the target shows may have geometry missing.

Either half of a scratch names the same renderer being short: a reservation that grew because a frame did not fit, or an overflow collected while the reservation was at its ceiling. The reservation changes as soon as the counters are collected, before the frame that dropped the geometry has been repainted whole for it, so a host that compares it here repaints again even when nothing was collected since.

pub fn note_scratch(&mut self, scratch: Scratch)

The renderer’s scratch is scratch now: once it changed since the target was brought up to date, the next frame repaints the whole target. Pixels drawn with geometry missing stay on it otherwise, since later frames repaint only what changes.

pub fn forget(&mut self)

The target no longer shows the last frame presented.

pub const fn shows_frame(&self) -> bool

Whether the target still holds the frame last presented: a host that acquired a surface texture for a frame it then skipped puts that on it again (crate::gpu::submit_target_to_surface) rather than presenting a cleared one.

Trait Implementations

impl Default for RetainedFrames

fn default() -> RetainedFrames

Returns the “default value” for a type.