forma::buffer::layout

Trait Layout

pub trait Layout {
    // Required methods
    fn width(&self) -> usize;
    fn height(&self) -> usize;
    fn slices_per_tile(&self) -> usize;
    fn slices<'l, 'b>(
        &'l mut self,
        buffer: &'b mut [u8],
    ) -> Ref<'l, [Slice<'b, u8>]>;
    fn write(
        slices: &mut [Slice<'_, u8>],
        flusher: Option<&dyn Flusher>,
        fill: TileFill<'_>,
    );

    // Provided methods
    fn width_in_tiles(&self) -> usize { ... }
    fn height_in_tiles(&self) -> usize { ... }
}
Expand description

A buffer’s layout description.

Implementors are supposed to cache sub-slices between uses provided they are being used with exactly the same buffer. This is achieved by storing a SliceCache in every layout implementation.

Required Methods§

fn width(&self) -> usize

Width in pixels.

§Examples
let layout = LinearLayout::new(2, 3 * 4, 4);

assert_eq!(layout.width(), 2);

fn height(&self) -> usize

Height in pixels.

§Examples
let layout = LinearLayout::new(2, 3 * 4, 4);

assert_eq!(layout.height(), 4);

fn slices_per_tile(&self) -> usize

Number of buffer sub-slices that will be passes to Layout::write.

§Examples
let layout = LinearLayout::new(2, 3 * 4, 4);

assert_eq!(layout.slices_per_tile(), TILE_HEIGHT);

fn slices<'l, 'b>( &'l mut self, buffer: &'b mut [u8], ) -> Ref<'l, [Slice<'b, u8>]>

Returns self-stored sub-slices of buffer which are stored in a SliceCache.

§Examples
let mut buffer = [
    [1; 4], [2; 4], [3; 4],
    [4; 4], [5; 4], [6; 4],
].concat();
let mut layout = LinearLayout::new(2, 3 * 4, 2);
let slices = layout.slices(&mut buffer);

assert_eq!(&*slices[0], &[[1; 4], [2; 4]].concat());
assert_eq!(&*slices[1], &[[4; 4], [5; 4]].concat());

fn write( slices: &mut [Slice<'_, u8>], flusher: Option<&dyn Flusher>, fill: TileFill<'_>, )

Writes fill to slices, optionally calling the flusher.

§Examples
let mut buffer = [
    [1; 4], [2; 4], [3; 4],
    [4; 4], [5; 4], [6; 4],
].concat();
let mut layout = LinearLayout::new(2, 3 * 4, 2);

LinearLayout::write(&mut *layout.slices(&mut buffer), None, TileFill::Solid([0; 4]));

assert_eq!(buffer, [
    [0; 4], [0; 4], [3; 4],
    [0; 4], [0; 4], [6; 4],
].concat());

Provided Methods§

fn width_in_tiles(&self) -> usize

Width in tiles.

§Examples
let layout = LinearLayout::new(2 * TILE_WIDTH, 3 * TILE_WIDTH * 4, 4 * TILE_HEIGHT);

assert_eq!(layout.width_in_tiles(), 2);

fn height_in_tiles(&self) -> usize

Height in tiles.

§Examples
let layout = LinearLayout::new(2 * TILE_WIDTH, 3 * TILE_WIDTH * 4, 4 * TILE_HEIGHT);

assert_eq!(layout.height_in_tiles(), 4);

Dyn Compatibility§

This trait is not dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety", so this trait is not object safe.

Implementors§