Font weight support

Cargo.toml

@@ -3480,6 +3480,17 @@ description = "Demonstrates how Display and Visibility work in the UI."
 category = "UI (User Interface)"
 wasm = true
 
+[[example]]
+name = "font_weights"
+path = "examples/ui/font_weights.rs"
+doc-scrape-examples = true
+
+[package.metadata.example.font_weights]
+name = "Font Weights"
+description = "Demonstrates how to use font weights."
+category = "UI (User Interface)"
+wasm = true
+
 [[example]]
 name = "window_fallthrough"
 path = "examples/ui/window_fallthrough.rs"

assets/fonts/OFL.txt

@@ -0,0 +1,93 @@
+Copyright 2022 The Mona Sans Project Authors (https://github.com/github/mona-sans), with Reserved Font Name "Mona"
+
+This Font Software is licensed under the SIL Open Font License, Version 1.1.
+This license is copied below, and is also available with a FAQ at:
+https://openfontlicense.org
+
+
+-----------------------------------------------------------
+SIL OPEN FONT LICENSE Version 1.1 - 26 February 2007
+-----------------------------------------------------------
+
+PREAMBLE
+The goals of the Open Font License (OFL) are to stimulate worldwide
+development of collaborative font projects, to support the font creation
+efforts of academic and linguistic communities, and to provide a free and
+open framework in which fonts may be shared and improved in partnership
+with others.
+
+The OFL allows the licensed fonts to be used, studied, modified and
+redistributed freely as long as they are not sold by themselves. The
+fonts, including any derivative works, can be bundled, embedded, 
+redistributed and/or sold with any software provided that any reserved
+names are not used by derivative works. The fonts and derivatives,
+however, cannot be released under any other type of license. The
+requirement for fonts to remain under this license does not apply
+to any document created using the fonts or their derivatives.
+
+DEFINITIONS
+"Font Software" refers to the set of files released by the Copyright
+Holder(s) under this license and clearly marked as such. This may
+include source files, build scripts and documentation.
+
+"Reserved Font Name" refers to any names specified as such after the
+copyright statement(s).
+
+"Original Version" refers to the collection of Font Software components as
+distributed by the Copyright Holder(s).
+
+"Modified Version" refers to any derivative made by adding to, deleting,
+or substituting -- in part or in whole -- any of the components of the
+Original Version, by changing formats or by porting the Font Software to a
+new environment.
+
+"Author" refers to any designer, engineer, programmer, technical
+writer or other person who contributed to the Font Software.
+
+PERMISSION & CONDITIONS
+Permission is hereby granted, free of charge, to any person obtaining
+a copy of the Font Software, to use, study, copy, merge, embed, modify,
+redistribute, and sell modified and unmodified copies of the Font
+Software, subject to the following conditions:
+
+1) Neither the Font Software nor any of its individual components,
+in Original or Modified Versions, may be sold by itself.
+
+2) Original or Modified Versions of the Font Software may be bundled,
+redistributed and/or sold with any software, provided that each copy
+contains the above copyright notice and this license. These can be
+included either as stand-alone text files, human-readable headers or
+in the appropriate machine-readable metadata fields within text or
+binary files as long as those fields can be easily viewed by the user.
+
+3) No Modified Version of the Font Software may use the Reserved Font
+Name(s) unless explicit written permission is granted by the corresponding
+Copyright Holder. This restriction only applies to the primary font name as
+presented to the users.
+
+4) The name(s) of the Copyright Holder(s) or the Author(s) of the Font
+Software shall not be used to promote, endorse or advertise any
+Modified Version, except to acknowledge the contribution(s) of the
+Copyright Holder(s) and the Author(s) or with their explicit written
+permission.
+
+5) The Font Software, modified or unmodified, in part or in whole,
+must be distributed entirely under this license, and must not be
+distributed under any other license. The requirement for fonts to
+remain under this license does not apply to any document created
+using the Font Software.
+
+TERMINATION
+This license becomes null and void if any of the above conditions are
+not met.
+
+DISCLAIMER
+THE FONT SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTIES OF
+MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT
+OF COPYRIGHT, PATENT, TRADEMARK, OR OTHER RIGHT. IN NO EVENT SHALL THE
+COPYRIGHT HOLDER BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+INCLUDING ANY GENERAL, SPECIAL, INDIRECT, INCIDENTAL, OR CONSEQUENTIAL
+DAMAGES, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+FROM, OUT OF THE USE OR INABILITY TO USE THE FONT SOFTWARE OR FROM
+OTHER DEALINGS IN THE FONT SOFTWARE.

crates/bevy_text/src/lib.rs

@@ -59,8 +59,8 @@ pub use text_access::*;
 pub mod prelude {
     #[doc(hidden)]
     pub use crate::{
-        Font, Justify, LineBreak, Strikethrough, StrikethroughColor, TextColor, TextError,
-        TextFont, TextLayout, TextSpan, Underline, UnderlineColor,
+        Font, FontWeight, Justify, LineBreak, Strikethrough, StrikethroughColor, TextColor,
+        TextError, TextFont, TextLayout, TextSpan, Underline, UnderlineColor,
     };
 }
 

crates/bevy_text/src/pipeline.rs

@@ -62,8 +62,6 @@ pub struct FontFaceInfo {
     pub stretch: cosmic_text::fontdb::Stretch,
     /// Allows italic or oblique faces to be selected
     pub style: cosmic_text::fontdb::Style,
-    /// The degree of blackness or stroke thickness
-    pub weight: cosmic_text::fontdb::Weight,
     /// Font family name
     pub family_name: Arc<str>,
 }
@@ -86,7 +84,7 @@ pub struct TextPipeline {
         LineHeight,
     )>,
     /// Buffered vec for collecting info for glyph assembly.
-    glyph_info: Vec<(AssetId<Font>, FontSmoothing, f32, f32, f32, f32)>,
+    glyph_info: Vec<(AssetId<Font>, FontSmoothing, f32, f32, f32, f32, u16)>,
 }
 
 impl TextPipeline {
@@ -270,6 +268,7 @@ impl TextPipeline {
                 0.,
                 0.,
                 0.,
+                text_font.weight.clamp().0,
             ));
         });
 
@@ -288,18 +287,13 @@ impl TextPipeline {
 
         update_result?;
 
-        for (font, _, size, strikethrough_offset, stroke, underline_offset) in
+        for (font, _, size, strikethrough_offset, stroke, underline_offset, weight) in
             self.glyph_info.iter_mut()
         {
             let Some((id, _)) = self.map_handle_to_font_id.get(font) else {
                 continue;
             };
-            let weight = font_system
-                .db()
-                .face(*id)
-                .map(|f| f.weight)
-                .unwrap_or(cosmic_text::Weight::NORMAL);
-            if let Some(font) = font_system.get_font(*id, weight) {
+            if let Some(font) = font_system.get_font(*id, cosmic_text::Weight(*weight)) {
                 let swash = font.as_swash();
                 let metrics = swash.metrics(&[]);
                 let upem = metrics.units_per_em as f32;
@@ -528,23 +522,19 @@ impl TextPipeline {
                 0.0,
                 0.0,
                 0.0,
+                text_font.weight.clamp().0,
             );
 
-            if let Some((id, _)) = self.map_handle_to_font_id.get(&section_info.0) {
-                let weight = font_system
-                    .db()
-                    .face(*id)
-                    .map(|f| f.weight)
-                    .unwrap_or(cosmic_text::Weight::NORMAL);
-                if let Some(font) = font_system.get_font(*id, weight) {
-                    let swash = font.as_swash();
-                    let metrics = swash.metrics(&[]);
-                    let upem = metrics.units_per_em as f32;
-                    let scalar = section_info.2 * scale_factor as f32 / upem;
-                    section_info.3 = (metrics.strikeout_offset * scalar).round();
-                    section_info.4 = (metrics.stroke_size * scalar).round().max(1.);
-                    section_info.5 = (metrics.underline_offset * scalar).round();
-                }
+            if let Some((id, _)) = self.map_handle_to_font_id.get(&section_info.0)
+                && let Some(font) = font_system.get_font(*id, cosmic_text::Weight(section_info.6))
+            {
+                let swash = font.as_swash();
+                let metrics = swash.metrics(&[]);
+                let upem = metrics.units_per_em as f32;
+                let scalar = section_info.2 * scale_factor as f32 / upem;
+                section_info.3 = (metrics.strikeout_offset * scalar).round();
+                section_info.4 = (metrics.stroke_size * scalar).round().max(1.);
+                section_info.5 = (metrics.underline_offset * scalar).round();
             }
             self.glyph_info.push(section_info);
         }
@@ -681,7 +671,7 @@ impl TextPipeline {
         // Check result.
         result?;
 
-        layout_info.size = box_size;
+        layout_info.size = box_size.ceil();
         Ok(())
     }
 }
@@ -824,7 +814,6 @@ pub fn load_font_to_fontdb(
     FontFaceInfo {
         stretch: face.stretch,
         style: face.style,
-        weight: face.weight,
         family_name: family_name.clone(),
     }
 }
@@ -843,7 +832,7 @@ fn get_attrs<'a>(
         .family(Family::Name(&face_info.family_name))
         .stretch(face_info.stretch)
         .style(face_info.style)
-        .weight(face_info.weight)
+        .weight(text_font.weight.into())
         .metrics(
             Metrics {
                 font_size: text_font.font_size,

crates/bevy_text/src/text.rs

@@ -266,6 +266,10 @@ pub struct TextFont {
     /// A new font atlas is generated for every combination of font handle and scaled font size
     /// which can have a strong performance impact.
     pub font_size: f32,
+    /// How thick or bold the strokes of a font appear.
+    ///
+    /// Font weights can be any value between 1 and 1000, inclusive.
+    pub weight: FontWeight,
     /// The antialiasing method to use when rendering text.
     pub font_smoothing: FontSmoothing,
     /// OpenType features for .otf fonts that support them.
@@ -308,12 +312,81 @@ impl Default for TextFont {
         Self {
             font: Default::default(),
             font_size: 20.0,
+            weight: FontWeight::NORMAL,
             font_features: FontFeatures::default(),
             font_smoothing: Default::default(),
         }
     }
 }
 
+/// How thick or bold the strokes of a font appear.
+///
+/// Valid font weights range from 1 to 1000, inclusive.
+/// Weights above 1000 are clamped to 1000.
+/// A weight of 0 is treated as [`FontWeight::DEFAULT`].
+///
+/// `<https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Properties/font-weight>`
+#[derive(Debug, Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Hash, Reflect)]
+pub struct FontWeight(pub u16);
+
+impl FontWeight {
+    /// Weight 100.
+    pub const THIN: FontWeight = FontWeight(100);
+
+    /// Weight 200.
+    pub const EXTRA_LIGHT: FontWeight = FontWeight(200);
+
+    /// Weight 300.
+    pub const LIGHT: FontWeight = FontWeight(300);
+
+    /// Weight 400.
+    pub const NORMAL: FontWeight = FontWeight(400);
+
+    /// Weight 500.
+    pub const MEDIUM: FontWeight = FontWeight(500);
+
+    /// Weight 600.
+    pub const SEMIBOLD: FontWeight = FontWeight(600);
+
+    /// Weight 700.
+    pub const BOLD: FontWeight = FontWeight(700);
+
+    /// Weight 800
+    pub const EXTRA_BOLD: FontWeight = FontWeight(800);
+
+    /// Weight 900.
+    pub const BLACK: FontWeight = FontWeight(900);
+
+    /// Weight 950.
+    pub const EXTRA_BLACK: FontWeight = FontWeight(950);
+
+    /// The default font weight.
+    pub const DEFAULT: FontWeight = Self::NORMAL;
+
+    /// Clamp the weight value to between 1 and 1000.
+    /// Values of 0 are mapped to `Weight::DEFAULT`.
+    pub const fn clamp(mut self) -> Self {
+        if self.0 == 0 {
+            self = Self::DEFAULT;
+        } else if 1000 < self.0 {
+            self.0 = 1000;
+        }
+        Self(self.0)
+    }
+}
+
+impl Default for FontWeight {
+    fn default() -> Self {
+        Self::DEFAULT
+    }
+}
+
+impl From<FontWeight> for cosmic_text::Weight {
+    fn from(value: FontWeight) -> Self {
+        cosmic_text::Weight(value.clamp().0)
+    }
+}
+
 /// An OpenType font feature tag.
 #[derive(Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Hash, Reflect)]
 pub struct FontFeatureTag([u8; 4]);

examples/README.md

@@ -567,6 +567,7 @@ Example | Description
 [Feathers Widgets](../examples/ui/feathers.rs) | Gallery of Feathers Widgets
 [Flex Layout](../examples/ui/flex_layout.rs) | Demonstrates how the AlignItems and JustifyContent properties can be composed to layout nodes and position text
 [Font Atlas Debug](../examples/ui/font_atlas_debug.rs) | Illustrates how FontAtlases are populated (used to optimize text rendering internally)
+[Font Weights](../examples/ui/font_weights.rs) | Demonstrates how to use font weights.
 [Ghost Nodes](../examples/ui/ghost_nodes.rs) | Demonstrates the use of Ghost Nodes to skip entities in the UI layout hierarchy
 [Gradients](../examples/ui/gradients.rs) | An example demonstrating gradients
 [Overflow](../examples/ui/overflow.rs) | Simple example demonstrating overflow behavior