Kamal Ahmad
41c373eff1
Closes #21319 Before:  After:  Use fontdb to load system fonts and pass it to resvg renderer. This adds a small increase in startup time (around 30ms on my Linux system to traverse fonts on a cold start). In the future once cosmic-text bumps their version of fontdb we could clone the Database from CosmicTextSystem Release Notes: - Added: support for rendering text in SVGs
102 lines
3.2 KiB
Rust
102 lines
3.2 KiB
Rust
use crate::{AssetSource, DevicePixels, IsZero, Result, SharedString, Size};
|
|
use anyhow::anyhow;
|
|
use resvg::tiny_skia::Pixmap;
|
|
use std::{
|
|
hash::Hash,
|
|
sync::{Arc, LazyLock},
|
|
};
|
|
|
|
/// When rendering SVGs, we render them at twice the size to get a higher-quality result.
|
|
pub const SMOOTH_SVG_SCALE_FACTOR: f32 = 2.;
|
|
|
|
#[derive(Clone, PartialEq, Hash, Eq)]
|
|
pub(crate) struct RenderSvgParams {
|
|
pub(crate) path: SharedString,
|
|
pub(crate) size: Size<DevicePixels>,
|
|
}
|
|
|
|
#[derive(Clone)]
|
|
pub struct SvgRenderer {
|
|
asset_source: Arc<dyn AssetSource>,
|
|
usvg_options: Arc<usvg::Options<'static>>,
|
|
}
|
|
|
|
pub enum SvgSize {
|
|
Size(Size<DevicePixels>),
|
|
ScaleFactor(f32),
|
|
}
|
|
|
|
impl SvgRenderer {
|
|
pub fn new(asset_source: Arc<dyn AssetSource>) -> Self {
|
|
let font_db = LazyLock::new(|| {
|
|
let mut db = usvg::fontdb::Database::new();
|
|
db.load_system_fonts();
|
|
Arc::new(db)
|
|
});
|
|
let default_font_resolver = usvg::FontResolver::default_font_selector();
|
|
let font_resolver = Box::new(
|
|
move |font: &usvg::Font, db: &mut Arc<usvg::fontdb::Database>| {
|
|
if db.is_empty() {
|
|
*db = font_db.clone();
|
|
}
|
|
default_font_resolver(font, db)
|
|
},
|
|
);
|
|
let options = usvg::Options {
|
|
font_resolver: usvg::FontResolver {
|
|
select_font: font_resolver,
|
|
select_fallback: usvg::FontResolver::default_fallback_selector(),
|
|
},
|
|
..Default::default()
|
|
};
|
|
Self {
|
|
asset_source,
|
|
usvg_options: Arc::new(options),
|
|
}
|
|
}
|
|
|
|
pub(crate) fn render(&self, params: &RenderSvgParams) -> Result<Option<Vec<u8>>> {
|
|
if params.size.is_zero() {
|
|
return Err(anyhow!("can't render at a zero size"));
|
|
}
|
|
|
|
// Load the tree.
|
|
let Some(bytes) = self.asset_source.load(¶ms.path)? else {
|
|
return Ok(None);
|
|
};
|
|
|
|
let pixmap = self.render_pixmap(&bytes, SvgSize::Size(params.size))?;
|
|
|
|
// Convert the pixmap's pixels into an alpha mask.
|
|
let alpha_mask = pixmap
|
|
.pixels()
|
|
.iter()
|
|
.map(|p| p.alpha())
|
|
.collect::<Vec<_>>();
|
|
Ok(Some(alpha_mask))
|
|
}
|
|
|
|
pub fn render_pixmap(&self, bytes: &[u8], size: SvgSize) -> Result<Pixmap, usvg::Error> {
|
|
let tree = usvg::Tree::from_data(bytes, &self.usvg_options)?;
|
|
|
|
let size = match size {
|
|
SvgSize::Size(size) => size,
|
|
SvgSize::ScaleFactor(scale) => crate::size(
|
|
DevicePixels((tree.size().width() * scale) as i32),
|
|
DevicePixels((tree.size().height() * scale) as i32),
|
|
),
|
|
};
|
|
|
|
// Render the SVG to a pixmap with the specified width and height.
|
|
let mut pixmap = resvg::tiny_skia::Pixmap::new(size.width.into(), size.height.into())
|
|
.ok_or(usvg::Error::InvalidSize)?;
|
|
|
|
let scale = size.width.0 as f32 / tree.size().width();
|
|
let transform = resvg::tiny_skia::Transform::from_scale(scale, scale);
|
|
|
|
resvg::render(&tree, transform, &mut pixmap.as_mut());
|
|
|
|
Ok(pixmap)
|
|
}
|
|
}
|