wip font stuff :p

hui-painter/src/lib.rs

@@ -1,5 +1,6 @@
 pub mod paint;
 pub mod texture;
+pub mod text;
 
 use texture::TextureAtlas;
 

hui-painter/src/paint/command/text.rs

@@ -1,15 +1,16 @@
 use std::{borrow::Cow, sync::Arc};
 use fontdue::layout::{CoordinateSystem, Layout};
-use crate::{paint::{
-  buffer::PaintBuffer,
-  command::PaintCommand,
-}, Painter};
-
-pub struct FontHandle(Arc<fontdue::Font>);
+use crate::{
+  Painter,
+  paint::{
+    buffer::PaintBuffer,
+    command::PaintCommand,
+  },
+};
 
 pub struct TextChunk {
   pub text: Cow<'static, str>,
-  pub font: FontHandle,
+  pub font: (),
   pub size: f32,
 }
 

hui-painter/src/paint/command/transform.rs

@@ -1,9 +1,10 @@
-use crate::{paint::{
-  buffer::PaintBuffer,
-  command::PaintCommand,
-}, Painter};
-
-//TODO: use generics instead
+use crate::{
+  Painter,
+  paint::{
+    buffer::PaintBuffer,
+    command::PaintCommand,
+  },
+};
 
 pub struct PaintTransform {
   pub transform: glam::Affine2,

hui-painter/src/text.rs

@@ -0,0 +1,2 @@
+pub mod ftm;
+pub mod font;

hui-painter/src/text/ftm.rs

@@ -0,0 +1,40 @@
+use fontdue::layout::GlyphRasterConfig;
+use hashbrown::HashMap;
+use nohash_hasher::BuildNoHashHasher;
+use crate::texture::{TextureAtlas, TextureHandle};
+
+type FontId = u16;
+
+#[derive(Clone, Copy)]
+pub struct FontHandle(FontId);
+
+/// Maps to the actual texture handle.
+struct GlyphCacheItem {
+  handle: TextureHandle,
+}
+
+/// Map from raster config to glyph cache item.
+///
+/// Partitioned by font id in FtM :3
+type PartitionKey = HashMap<GlyphRasterConfig, GlyphCacheItem>;
+
+/// Manages glyph cache items in a texture atlas.
+pub struct FontTextureManager {
+  partition: HashMap<FontId, PartitionKey, BuildNoHashHasher<FontId>>,
+}
+
+impl FontTextureManager {
+  /// Drop cached data for the specified font.
+  ///
+  /// Panics:
+  /// - If the font handle is invalid.
+  /// - If any of the cached items are not found in the texture atlas or became invalid.\
+  ///   This may happen if, for example, a different atlas is passed than the one used to allocate the items.
+  fn drop_font(&mut self, font: FontHandle, atlas: &mut TextureAtlas) {
+    let dump = self.partition.remove(&font.0).expect("Font handle is invalid");
+    for (_, item) in dump {
+      atlas.deallocate(item.handle);
+    }
+  }
+}
+