Struct AttrGrid 

pub struct AttrGrid<'a>(/* private fields */);

Available on crate feature cgb only.

A rectangle of attribute bytes, with the row stride of the grid it sits in.

A level map is wider than a tilemap, so the strip that scrolls into view is not contiguous in the source. Binding the stride to the data rather than passing it alongside keeps the two from being paired wrongly, and the two kinds of grid are separate types so that one cannot be written where the other belongs.

const LEVEL: AttrGrid = AttrGrid::new(&DATA, 100);
map::write(d, Map::Zero, x, 0, LEVEL.sub(col, 0, 1, 18));

Implementations

impl<'a> AttrGrid<'a>

pub const fn new(data: &'a [u8], width: u8) -> Self

All of data, laid out width cells per row.

The height follows from the length, so a partial last row is dropped, and so is anything past row 255.

Panics

If width is zero.

pub const fn sub(self, x: u8, y: u8, w: u8, h: u8) -> Self

The w by h rectangle at (x, y) within this one.

Not checked here. One reaching outside the data it was built from is refused when it is written, not when it is taken.

pub const fn width(self) -> u8

Cells across.

pub const fn height(self) -> u8

Cells down.

Trait Implementations

impl<'a> Clone for AttrGrid<'a>

fn clone(&self) -> AttrGrid<'a>

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl<'a> Copy for AttrGrid<'a>