feature/fontique - switch femtovg over and use a default fontdb for usvg (#9426)

* Use default fontdb for usvg

* Start adapting femtovg

* Use DesignFontMetrics from sharedfontique

* Restore fallback fonts

* [autofix.ci] apply automated fixes

* Add allow(dead_code) tag

* [autofix.ci] apply automated fixes

* Tiny comment change

---------

Co-authored-by: autofix-ci[bot] <114827586+autofix-ci[bot]@users.noreply.github.com>

Author: expenses

internal/common/Cargo.toml

@@ -19,7 +19,7 @@ path = "lib.rs"
 [features]
 default = []
 shared-fontdb = ["dep:fontdb", "dep:libloading", "derive_more", "cfg-if", "dep:ttf-parser"]
-shared-fontique = ["dep:fontique"]
+shared-fontique = ["dep:fontique", "dep:ttf-parser"]
 
 [dependencies]
 fontdb = { workspace = true, optional = true }

internal/common/sharedfontique.rs

@@ -2,6 +2,7 @@
 // SPDX-License-Identifier: GPL-3.0-only OR LicenseRef-Slint-Royalty-free-2.0 OR LicenseRef-Slint-Software-3.0
 
 pub use fontique;
+pub use ttf_parser;
 
 static COLLECTION: std::sync::LazyLock<Collection> = std::sync::LazyLock::new(|| Collection {
     inner: fontique::Collection::new(fontique::CollectionOptions {
@@ -30,3 +31,41 @@ impl Collection {
         self.inner.register_fonts(data.into(), None).len()
     }
 }
+
+impl std::ops::Deref for Collection {
+    type Target = fontique::Collection;
+
+    fn deref(&self) -> &Self::Target {
+        &self.inner
+    }
+}
+
+impl std::ops::DerefMut for Collection {
+    fn deref_mut(&mut self) -> &mut Self::Target {
+        &mut self.inner
+    }
+}
+
+/// Font metrics in design space. Scale with desired pixel size and divided by units_per_em
+/// to obtain pixel metrics.
+#[derive(Clone)]
+pub struct DesignFontMetrics {
+    pub ascent: f32,
+    pub descent: f32,
+    pub x_height: f32,
+    pub cap_height: f32,
+    pub units_per_em: f32,
+}
+
+impl DesignFontMetrics {
+    pub fn new(font: &fontique::QueryFont) -> Self {
+        let face = ttf_parser::Face::parse(font.blob.data(), font.index).unwrap();
+        Self {
+            ascent: face.ascender() as f32,
+            descent: face.descender() as f32,
+            x_height: face.x_height().unwrap_or_default() as f32,
+            cap_height: face.capital_height().unwrap_or_default() as f32,
+            units_per_em: face.units_per_em() as f32,
+        }
+    }
+}

internal/compiler/passes/embed_images.rs

@@ -372,8 +372,8 @@ fn load_image(
     if file.canon_path.extension() == Some(OsStr::new("svg"))
         || file.canon_path.extension() == Some(OsStr::new("svgz"))
     {
-        let tree = i_slint_common::sharedfontdb::FONT_DB.with_borrow(|db| {
-            let option = usvg::Options { fontdb: (*db).clone(), ..Default::default() };
+        let tree = {
+            let option = usvg::Options::default();
             match file.builtin_contents {
                 Some(data) => usvg::Tree::from_data(data, &option),
                 None => usvg::Tree::from_data(
@@ -387,7 +387,7 @@ fn load_image(
                     e,
                 ))
             })
-        })?;
+        }?;
         let scale_factor = scale_factor as f32;
         // TODO: ideally we should find the size used for that `Image`
         let original_size = tree.size();

internal/core/graphics.rs

@@ -155,19 +155,6 @@ pub struct FontRequest {
     pub italic: bool,
 }
 
-#[cfg(feature = "shared-fontdb")]
-impl FontRequest {
-    /// Returns the relevant properties of this FontRequest propagated into a fontdb Query.
-    pub fn to_fontdb_query(&self) -> i_slint_common::sharedfontdb::fontdb::Query<'_> {
-        use i_slint_common::sharedfontdb::fontdb::{Query, Style, Weight};
-        Query {
-            style: if self.italic { Style::Italic } else { Style::Normal },
-            weight: Weight(self.weight.unwrap_or(/* CSS normal*/ 400) as _),
-            ..Default::default()
-        }
-    }
-}
-
 #[cfg(feature = "shared-fontique")]
 impl FontRequest {
     /// Attempts to query the fontique font collection for a matching font.

internal/core/graphics/image/svg.rs

@@ -81,17 +81,13 @@ pub fn load_from_path(
 ) -> Result<ParsedSVG, std::io::Error> {
     let svg_data = std::fs::read(std::path::Path::new(&path.as_str()))?;
 
-    i_slint_common::sharedfontdb::FONT_DB.with_borrow(|db| {
-        let option = usvg::Options { fontdb: (*db).clone(), ..Default::default() };
-        usvg::Tree::from_data(&svg_data, &option)
-            .map(|svg| ParsedSVG { svg_tree: svg, cache_key })
-            .map_err(|e| std::io::Error::new(std::io::ErrorKind::Other, e))
-    })
+    let option = usvg::Options::default();
+    usvg::Tree::from_data(&svg_data, &option)
+        .map(|svg| ParsedSVG { svg_tree: svg, cache_key })
+        .map_err(|e| std::io::Error::new(std::io::ErrorKind::Other, e))
 }
 
 pub fn load_from_data(slice: &[u8], cache_key: ImageCacheKey) -> Result<ParsedSVG, usvg::Error> {
-    i_slint_common::sharedfontdb::FONT_DB.with_borrow(|db| {
-        let option = usvg::Options { fontdb: (*db).clone(), ..Default::default() };
-        usvg::Tree::from_data(slice, &option).map(|svg| ParsedSVG { svg_tree: svg, cache_key })
-    })
+    let option = usvg::Options::default();
+    usvg::Tree::from_data(slice, &option).map(|svg| ParsedSVG { svg_tree: svg, cache_key })
 }

internal/renderers/femtovg/Cargo.toml

@@ -23,7 +23,7 @@ wgpu-26 = ["dep:wgpu-26", "femtovg/wgpu", "i-slint-core/unstable-wgpu-26"]
 unstable-wgpu-26 = ["wgpu-26"]
 
 [dependencies]
-i-slint-core = { workspace = true, features = ["default", "box-shadow-cache", "shared-fontdb"] }
+i-slint-core = { workspace = true, features = ["default", "box-shadow-cache", "shared-fontique"] }
 i-slint-core-macros = { workspace = true, features = ["default"] }
 i-slint-common = { workspace = true, features = ["default", "shared-fontique"] }