Typograffiti.Store

A storage context an ops for rendering text with multiple fonts and sizes, hiding the details of the Atlas, Cache, and the Harfbuzz library.

Documentation

data FontStore n

Stored fonts at specific sizes.

Constructors

FontStore

Fields

• fontMap :: TMVar (Map (FilePath, GlyphSize, Int, FontOptions) Font)

  Map for looking up previously-opened fonts & their atlases.

• drawGlyphs :: Atlas -> [(GlyphInfo, GlyphPos)] -> n (AllocatedRendering [TextTransform])

  Cached routine for compositing from the given atlas.

• lib :: FT_Library

  Globals for FreeType.

data Font

An opened font. In Harfbuzz, FreeType, & Atlas formats.

Constructors

Font

Fields

• harfbuzz :: Font

  Font as represented by Harfbuzz.

• freetype :: FT_Face

  Font as represented by FreeType.

• atlases :: TMVar [(IntSet, Atlas)]

  Glyphs from the font rendered into GPU atleses.

makeDrawTextCached :: (MonadIO m, MonadFail m, MonadError TypograffitiError m, MonadIO n, MonadFail n, MonadError TypograffitiError n) => FontStore n -> FilePath -> Int -> GlyphSize -> SampleText -> m (RichText -> n (AllocatedRendering [TextTransform]))

Opens a font sized to given value & prepare to render text in it. The fonts are cached for later reuse.

allocFont :: (MonadIO m, MonadError TypograffitiError m) => FontStore n -> FilePath -> Int -> GlyphSize -> FontOptions -> m Font

Opens & sizes the given font using both FreeType & Harfbuzz, loading it into the FontStore before returning.

allocAtlas' :: (MonadIO m, MonadFail m, MonadError TypograffitiError m) => TMVar [(IntSet, Atlas)] -> FT_Face -> IntSet -> m Atlas

Allocates a new Atlas for the given font & glyphset, loading it into the atlas cache before returning.

freeFonts :: (MonadIO m, MonadError TypograffitiError m) => FontStore n -> Maybe FilePath -> Maybe Int -> Maybe GlyphSize -> m IntSet

Frees fonts identified by filepath, index, and/or fontsize. Returns the glyphsets covered by their newly-freed atlases in case callers wish to make an informed reallocation.

withFontStore :: (MonadIO n, MonadError TypograffitiError n, MonadFail n) => (FontStore n -> ExceptT TypograffitiError IO a) -> IO (Either TypograffitiError a)

Runs the given callback with a new FontStore. Due to FreeType limitations this font store should not persist outside the callback.

newFontStore :: (MonadIO m, MonadError TypograffitiError m, MonadIO n, MonadError TypograffitiError n, MonadFail n) => FT_Library -> m (FontStore n)

Allocates a new FontStore wrapping given FreeType state.