Expose slice and vec of raw data (#98)

* Expose slice and vec of raw data

* Fix formatting

* Restore methods directly on FontVec

* Format

* Remove methods from Font, add a new trait and just use as_slice

* Fix merged trait usage

* Use a default and implement per type data impls

* Fix docs

* Restore blank

* Fixes and feedback

* Fix fmt

---------

Co-authored-by: Alex Parlett <alexparlett@Alexs-MacBook-Air.local>

glyph/src/font.rs

@@ -243,6 +243,23 @@ pub trait Font {
             scale: scale.into(),
         }
     }
+
+    /// Extracts a slice containing the data passed into e.g. [`FontArc::try_from_slice`].
+    ///
+    /// # Example
+    /// ```
+    /// # use ab_glyph::*;
+    /// # fn main() -> Result<(), InvalidFont> {
+    /// # let owned_font_data = include_bytes!("../../dev/fonts/Exo2-Light.otf");
+    /// let font = FontArc::try_from_slice(owned_font_data)?;
+    /// assert_eq!(font.font_data(), owned_font_data);
+    /// # Ok(()) }
+    /// ```
+    #[inline]
+    fn font_data(&self) -> &[u8] {
+        // panic impl prevents this method from breaking external Font impls
+        unimplemented!()
+    }
 }
 
 impl<F: Font> Font for &F {
@@ -315,4 +332,9 @@ impl<F: Font> Font for &F {
     fn glyph_raster_image2(&self, id: GlyphId, size: u16) -> Option<v2::GlyphImage> {
         (*self).glyph_raster_image2(id, size)
     }
+
+    #[inline]
+    fn font_data(&self) -> &[u8] {
+        (*self).font_data()
+    }
 }

glyph/src/font_arc.rs

@@ -140,6 +140,11 @@ impl Font for FontArc {
     fn glyph_raster_image2(&self, id: GlyphId, size: u16) -> Option<v2::GlyphImage> {
         self.0.glyph_raster_image2(id, size)
     }
+
+    #[inline]
+    fn font_data(&self) -> &[u8] {
+        self.0.font_data()
+    }
 }
 
 impl From<FontVec> for FontArc {

glyph/src/ttfp.rs

@@ -172,6 +172,7 @@ impl FontVec {
     /// assert_eq!(font.into_vec(), font_data_clone);
     /// # Ok(()) }
     /// ```
+    #[inline]
     pub fn into_vec(self) -> Vec<u8> {
         self.0.face.into_vec()
     }
@@ -341,6 +342,11 @@ macro_rules! impl_font {
                     },
                 })
             }
+
+            #[inline]
+            fn font_data(&self) -> &[u8] {
+                self.0.face.as_face_ref().raw_face().data
+            }
         }
     };
 }