textium: tweak GlyphMetadata, remove FontPacker, FontTexture

textium/src/lib.rs

@@ -21,23 +21,19 @@ pub use geometry::Rect;
 /// Information used to render a glyph in a font.
 #[derive(Debug)]
 pub struct GlyphMetadata {
-    /// Coordinates of the top left of this glyph in the font's texture
-    texture_coord: (f32, f32),
-
-    /// Width and height of the glyph's texture.
-    texture_size: (f32, f32),
-
-    /// Size of the glyph, in ems.
-    em_size: (f32, f32),
+    /// Bounding box in the packed texture
+    bounding_box: Rect<usize>,
+    /// Scale that the character was rendered at
+    scale: f32,
 
     /// Distance between the bottom of the glyph and the baseline, in ems.
-    baseline_distance: f32,
+    // baseline_distance: f32,
 
-    /// Left padding on the glyph, in ems.
-    left_padding: f32,
+    /// Distance to advance in layout after this character
+    advance_width: f32,
 
-    /// Left padding on the glyph, in ems.
-    right_padding: f32,
+    /// Horizontal offset between glyph origin and leftmost point of the glyph
+    left_bearing: f32,
 }
 
 pub struct FontAtlas {
@@ -52,60 +48,3 @@ pub struct FontTexture {
     atlas: FontAtlas,
 }
 
-pub trait FontPacker {
-    fn pack<C>(&self, font: Font, characters: C, font_size: u32) -> Result<(Texture2dData<f32>, HashMap<char, GlyphMetadata>), Error>
-        where C: Iterator<Item=char>;
-}
-
-pub struct NaiveFontPacker;
-impl FontPacker for NaiveFontPacker {
-    fn pack<C>(&self, font: Font, characters: C, font_size: u32) -> Result<(Texture2dData<f32>, HashMap<char, GlyphMetadata>), Error>
-        where C: Iterator<Item=char>
-    {
-        // Margin around each character in the texture
-        const MARGIN: u32 = 2;
-
-        let invalid_char_width = font_size / 2;
-
-        let estimated_glyphs = characters.size_hint().1.unwrap_or(0);
-
-        let mut texture_data: Vec<f32> = Vec::with_capacity(
-            estimated_glyphs * (font_size as usize).pow(2));
-
-        let texture_width = get_nearest_pow2(std::cmp::max(font_size * 2,
-            (((estimated_glyphs as u32) * font_size.pow(2)) as f32).sqrt() as u32));
-
-        let mut cursor = (0u32, 0u32);
-        let mut skip_rows = 0u32;
-
-        // let glyph_metadata = characters.map(|character| {
-        //     let scaled_glyph = font.glyph(character)
-        //         .ok_or_else(|| Error::NotAGlyph(character))?
-        //         .scaled(rusttype::Scale::uniform(font_size as f32));
-
-        //     // let h_metrics =
-        // }).collect::<Result<Vec<_>, Error>>()?;
-
-
-        Err(Error::PackingError)
-    }
-}
-
-// TODO: make this an actual From once TryFrom is stabilized.
-impl FontTexture {
-    /// Load a font from a Rusttype font into a Textium font texture, and upload it to Glium.
-    pub fn from_font<T>(font: Font, font_size: u32, facade: &Facade, packer: T) -> Result<FontTexture, Error>
-        where T: FontPacker
-    {
-        let characters: Vec<char> = (0..255).filter_map(|c| ::std::char::from_u32(c)).collect();
-
-        let (texture_data, meta) = packer.pack(font, characters.into_iter(), font_size)?;
-
-        let texture = Texture2d::new(facade, &texture_data)?;
-
-        Ok(FontTexture {
-            texture: texture,
-            glyph_metadata: meta,
-        })
-    }
-}