Struct DamageTracker 

pub struct DamageTracker { /* private fields */ }

Accumulates per-frame damage and resolves it against buffer age.

One tracker per surface. Call add as things change, resolve once you know the age of the buffer you got, and end_frame after presenting.

Implementations

impl DamageTracker

pub fn new(size: Size) -> Self

Creates a tracker for a surface of size, starting fully damaged.

pub const fn surface_size(&self) -> Size

Surface extent damage is clipped against.

pub fn resize(&mut self, size: Size)

Resizes the surface. Every buffer in flight is now the wrong shape, so all history is discarded and the next frame is a full repaint.

pub fn add(&mut self, rect: Rect)

Marks a region of the current frame dirty. Clipped to the surface.

pub fn add_full(&mut self)

Marks the whole surface dirty for this frame.

pub fn is_clean(&self) -> bool

Returns true if nothing has been marked dirty this frame.

pub fn pending(&self) -> &[Rect]

What has been marked dirty this frame, before any buffer age widens it.

Distinct from resolved, which is the answer resolve last gave and therefore describes the previous frame until this one is resolved. This is what a caller wants when it has to hand one tracker’s damage to another before either has seen a buffer — a tree inside a backend’s event loop, which is exactly the arrangement DeniseApp::update puts them in.

Empty when the whole surface is marked: there is no rectangle list in that case, and is_clean is how to tell the two apart.

pub fn resolve(&mut self, age: BufferAge) -> &[Rect]

Damage that must actually be repainted into a buffer of the given age.

For BufferAge::Frames(n) this is the union of the last n frames’ damage, current frame included. For BufferAge::Undefined, or an age deeper than MAX_TRACKED_FRAMES, it is the whole surface.

Pass the result to both the renderer and crate::Surface::present.

pub fn resolved(&self) -> &[Rect]

The slice most recently returned by resolve.

pub fn end_frame(&mut self)

Advances to the next frame, retiring the oldest history slot.

Trait Implementations

impl Clone for DamageTracker

fn clone(&self) -> DamageTracker

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for DamageTracker

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

Formats the value using the given formatter.