First commit. Version 0.1.0

src/render/setup.rs

@@ -0,0 +1,124 @@
+// SPDX-License-Identifier: LGPL-2.1-only
+// Copyright (C) 2026 Liberux Labs, S. L. <info@liberux.net>
+
+//! Construction + accessors for [`SoftwareCanvas`]: new / sub_canvas
+//! / resize plus the font-registry installer and `blit`.
+
+use std::collections::HashMap;
+use std::sync::{ Arc, OnceLock };
+
+use fontdue::{ Font, FontSettings };
+use tiny_skia::{ Pixmap, PixmapPaint, Transform };
+
+use crate::theme::{ FontRegistry, FontStyle };
+
+use super::helpers::load_default_font_bytes;
+use super::SoftwareCanvas;
+
+/// Process-wide cache of the default font face. Avoids re-reading +
+/// re-parsing the file on every surface bring-up. Sora is small
+/// (~50 KB) so the cost was minor in absolute terms — but a layer
+/// shell that brings up a launcher overlay, a QS panel, a calendar
+/// popup and a handful of toast surfaces would still pay the parse
+/// cost a dozen times in a single session, all of which is wasted
+/// work.
+static DEFAULT_FONT: OnceLock<Arc<Font>> = OnceLock::new();
+
+fn default_font() -> Arc<Font>
+{
+	Arc::clone( DEFAULT_FONT.get_or_init( ||
+	{
+		let bytes = load_default_font_bytes();
+		let font  = Font::from_bytes( bytes.as_slice(), FontSettings::default() )
+			.expect( "bad font" );
+		Arc::new( font )
+	} ) )
+}
+
+impl SoftwareCanvas
+{
+	/// Create a canvas of the given pixel dimensions, loading a system font.
+	///
+	/// Fallback fonts (Noto Sans / CJK / Devanagari / …) are NOT loaded
+	/// here — they are owned by the crate-private system-fonts chain
+	/// and loaded lazily per codepoint. A canvas that only ever paints
+	/// Latin text will never touch those files; the first non-Latin
+	/// glyph triggers a single targeted load and the rest of the
+	/// process reuses the cached `Arc<Font>`.
+	pub fn new( width: u32, height: u32 ) -> Self
+	{
+		Self
+		{
+			pixmap:          Pixmap::new( width, height ).expect( "pixmap" ),
+			font:            default_font(),
+			font_registry:   None,
+			dpi_scale:       1.0,
+			global_alpha:    1.0,
+			glyph_cache:     HashMap::new(),
+			clip_mask:       None,
+			clip_bounds:     Vec::new(),
+		}
+	}
+
+	/// Create a blank sub-canvas sharing the same font and DPI scale.
+	pub fn sub_canvas( &self, width: u32, height: u32 ) -> SoftwareCanvas
+	{
+		SoftwareCanvas
+		{
+			pixmap:         Pixmap::new( width, height ).expect( "pixmap" ),
+			font:           Arc::clone( &self.font ),
+			font_registry:  self.font_registry.as_ref().map( Arc::clone ),
+			dpi_scale:      self.dpi_scale,
+			global_alpha:   self.global_alpha,
+			glyph_cache:    HashMap::new(),
+			clip_mask:      None,
+			clip_bounds:    Vec::new(),
+		}
+	}
+
+	/// Install a theme font registry so [`Self::font_for`] can
+	/// resolve family+weight+style triples declared by the theme's
+	/// `fonts` block. The default [`Self::font`] stays in place as a
+	/// fallback.
+	pub fn set_font_registry( &mut self, registry: Arc<FontRegistry> )
+	{
+		self.font_registry = Some( registry );
+	}
+
+	/// Resolve a specific font from the theme registry, falling back
+	/// to the canvas' default [`Self::font`] when no registry is
+	/// installed or the triple cannot be satisfied.
+	pub fn font_for( &self, family: &str, weight: u16, style: FontStyle ) -> Arc<Font>
+	{
+		self.font_registry
+			.as_ref()
+			.and_then( |r| r.resolve( family, weight, style ) )
+			.unwrap_or_else( || Arc::clone( &self.font ) )
+	}
+
+	/// Pick the right font for `ch`. Tries the primary [`Self::font`]
+	/// first; on a miss, delegates to the crate-private system-fonts
+	/// fallback chain (lazy load of the relevant Noto pack). Falls
+	/// back to the primary (which paints a `.notdef` box) when no
+	/// installed fallback covers the codepoint.
+	pub fn font_for_char( &self, ch: char ) -> Arc<Font>
+	{
+		if self.font.lookup_glyph_index( ch ) != 0
+		{
+			return Arc::clone( &self.font );
+		}
+		crate::system_fonts::lookup( ch ).unwrap_or_else( || Arc::clone( &self.font ) )
+	}
+
+	pub fn blit( &mut self, src: &SoftwareCanvas, dest_x: i32, dest_y: i32 )
+	{
+		let paint = PixmapPaint::default();
+		let t     = Transform::from_translate( dest_x as f32, dest_y as f32 );
+		self.pixmap.draw_pixmap( 0, 0, src.pixmap.as_ref(), &paint, t, self.clip_mask.as_ref() );
+	}
+
+	pub fn resize( &mut self, width: u32, height: u32 )
+	{
+		self.pixmap = Pixmap::new( width, height ).expect( "pixmap" );
+	}
+}