Struct alacritty::renderer::Atlas

struct Atlas {
    id: c_uint,
    width: i32,
    height: i32,
    row_extent: i32,
    row_baseline: i32,
    row_tallest: i32,
}

Manages a single texture atlas.

The strategy for filling an atlas looks roughly like this:

                          (width, height)
  ┌─────┬─────┬─────┬─────┬─────┐
  │ 10  │     │     │     │     │ <- Empty spaces; can be filled while
  │     │     │     │     │     │    glyph_height < height - row_baseline
  ├─────┼─────┼─────┼─────┼─────┤
  │ 5   │ 6   │ 7   │ 8   │ 9   │
  │     │     │     │     │     │
  ├─────┼─────┼─────┼─────┴─────┤ <- Row height is tallest glyph in row; this is
  │ 1   │ 2   │ 3   │ 4         │    used as the baseline for the following row.
  │     │     │     │           │ <- Row considered full when next glyph doesn't
  └─────┴─────┴─────┴───────────┘    fit in the row.
(0, 0)  x->

Fields

id: c_uint

Texture id for this atlas.

width: i32

Width of atlas.

height: i32

Height of atlas.

row_extent: i32

Left-most free pixel in a row.

This is called the extent because it is the upper bound of used pixels in a row.

row_baseline: i32

Baseline for glyphs in the current row.

row_tallest: i32

Tallest glyph in current row.

This is used as the advance when end of row is reached.

Implementations

impl Atlas

fn new(size: i32) -> Self

pub fn clear(&mut self)

pub fn insert(
    &mut self,
    glyph: &RasterizedGlyph,
    active_tex: &mut u32
) -> Result<Glyph, AtlasInsertError>

Insert a RasterizedGlyph into the texture atlas.

fn insert_inner(
    &mut self,
    glyph: &RasterizedGlyph,
    active_tex: &mut u32
) -> Glyph

Insert the glyph without checking for room.

Internal function for use once atlas has been checked for space. GL errors could still occur at this point if we were checking for them; hence, the Result.

fn room_in_row(&self, raw: &RasterizedGlyph) -> bool

Check if there’s room in the current row for given glyph.

fn advance_row(&mut self) -> Result<(), AtlasInsertError>

Mark current row as finished and prepare to insert into the next row.

Trait Implementations

impl Debug for Atlas

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

Formats the value using the given formatter.

impl Drop for Atlas

fn drop(&mut self)

Executes the destructor for this type.