Rework font cache to cache on paths

This is done in order to help prevent us from loading the same
font face over and over again under separate keys.  We still incur
the performance hit of doing the fontconfig search each new glyph,
but that's unavoidable without more extensive refactoring.
This commit is contained in:
Harlan Lieberman-Berg 2017-02-27 21:43:21 -05:00 committed by Joe Wilm
parent 3ad6869967
commit 50f27af643
1 changed files with 24 additions and 14 deletions

View File

@ -27,7 +27,7 @@ use super::{FontDesc, RasterizedGlyph, Metrics, Size, FontKey, GlyphKey, Weight,
pub struct FreeTypeRasterizer {
faces: HashMap<FontKey, Face<'static>>,
library: Library,
keys: HashMap<FontDesc, FontKey>,
keys: HashMap<::std::path::PathBuf, FontKey>,
dpi_x: u32,
dpi_y: u32,
dpr: f32,
@ -75,15 +75,10 @@ impl ::Rasterize for FreeTypeRasterizer {
}
fn load_font(&mut self, desc: &FontDesc, _size: Size) -> Result<FontKey, Error> {
self.keys
.get(&desc.to_owned())
.map(|k| Ok(*k))
.unwrap_or_else(|| {
let face = self.get_face(desc)?;
let key = FontKey::next();
self.faces.insert(key, face);
Ok(key)
})
let face = self.get_face(desc)?;
let key = FontKey::next();
self.faces.insert(key, face);
Ok(key)
}
fn get_glyph(&mut self, glyph_key: &GlyphKey) -> Result<RasterizedGlyph, Error> {
@ -246,11 +241,26 @@ impl FreeTypeRasterizer {
match fc::font_match(config, &mut pattern) {
Some(font) => {
if let (Some(path), Some(index)) = (font.file(0), font.index(0)) {
let face = self.library.new_face(path, index)?;
let key = FontKey::next();
self.faces.insert(key, face);
return Ok(key)
match self.keys.get(&path.to_path_buf()) {
// We've previously loaded this font, so don't
// load it again.
Some(&key) => {
debug!("Hit for font {:?}", path);
return Ok(key)
},
None => {
debug!("Miss for font {:?}", path);
let pathbuf = path.to_path_buf();
let face = self.library.new_face(path, index)?;
let key = FontKey::next();
self.keys.insert(pathbuf, key);
self.faces.insert(key, face);
return Ok(key)
}
}
}
Err(Error::MissingFont(
FontDesc::new("fallback-without-path", Style::Specific(glyph.to_string()))
))