Struct DoubleBuffer 

pub struct DoubleBuffer { /* private fields */ }

Double-buffered render target with O(1) swap.

Maintains two pre-allocated buffers and swaps between them by flipping an index, avoiding the O(width × height) clone that a naive prev/current pattern requires.

Invariants

1. Both buffers always have the same dimensions.
2. swap() is O(1) — it only flips the index, never copies cells.
3. After swap(), current_mut().clear() should be called to prepare the new frame buffer.
4. resize() discards both buffers and returns true so callers know a full redraw is needed.

Implementations

impl DoubleBuffer

pub fn new(width: u16, height: u16) -> Self

Create a double buffer with the given dimensions.

Both buffers are initialized to default (empty) cells.

Panics

Panics if width or height is 0.

pub fn swap(&mut self)

O(1) swap: the current buffer becomes previous, and vice versa.

After swapping, call current_mut().clear() to prepare for the next frame.

pub fn current(&self) -> &Buffer

Reference to the current (in-progress) frame buffer.

pub fn current_mut(&mut self) -> &mut Buffer

Mutable reference to the current (in-progress) frame buffer.

pub fn previous(&self) -> &Buffer

Reference to the previous (last-presented) frame buffer.

pub fn previous_mut(&mut self) -> &mut Buffer

Mutable reference to the previous (last-presented) frame buffer.

pub fn width(&self) -> u16

Width of both buffers.

pub fn height(&self) -> u16

Height of both buffers.

pub fn resize(&mut self, width: u16, height: u16) -> bool

Resize both buffers. Returns true if dimensions actually changed.

Both buffers are replaced with fresh allocations and the index is reset. Callers should force a full redraw when this returns true.

pub fn dimensions_match(&self, width: u16, height: u16) -> bool

Check whether both buffers have the given dimensions.

Trait Implementations

impl Debug for DoubleBuffer

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

Formats the value using the given formatter.