Squashed commit of the following:

commit 79098b2523f6009824d3992dc98c24944d49c784
Author: griffi-gh <prasol258@gmail.com>
Date:   Sat Sep 28 10:46:00 2024 +0200

    Revert "wip integrate hui-painter instead of `hui::draw`"

    This reverts commit 3d01377eb2.

commit 3d01377eb2
Author: griffi-gh <prasol258@gmail.com>
Date:   Fri Sep 27 21:42:58 2024 +0200

    wip integrate hui-painter instead of `hui::draw`

hui-painter/src/lib.rs

@@ -1,17 +1,19 @@
 pub mod paint;
 pub mod texture;
 pub mod text;
+pub mod util;
 
 use text::FontManager;
 use texture::TextureAtlas;
 
+/// Painter instance, stores textures and fonts needed for rendering
 #[derive(Default)]
-pub struct Painter {
+pub struct PainterInstance {
   pub atlas: TextureAtlas,
   pub fonts: FontManager,
 }
 
-impl Painter {
+impl PainterInstance {
   pub fn new() -> Self {
     Self::default()
   }

hui-painter/src/paint/command.rs

@@ -1,9 +1,12 @@
 use glam::Vec2;
-use crate::{paint::buffer::PaintBuffer, Painter};
+use crate::{paint::buffer::PaintBuffer, PainterInstance};
 
 // mod root;
 // pub use root::RootCommand;
 
+mod list;
+pub use list::PaintList;
+
 mod transform;
 pub use transform::PaintTransform;
 
@@ -19,15 +22,30 @@ pub trait PaintCommand {
   ///
   /// Make sure to propagate this call to children!
   #[allow(unused_variables)]
-  fn pre_paint(&self, ctx: &mut Painter) {}
+  fn pre_paint(&self, ctx: &mut PainterInstance) {}
 
   /// Paint the command into the buffer
   ///
   /// Do not allocate new textures or cache glyphs here, use `pre_paint` instead!\
   /// (Doing this WILL lead to atlas corruption flicker for a single frame if it's forced to resize!)
-  fn paint(&self, ctx: &mut Painter, into: &mut PaintBuffer);
+  fn paint(&self, ctx: &mut PainterInstance, into: &mut PaintBuffer);
 }
 
 pub trait Measurable: PaintCommand {
-  fn size(&self, ctx: &Painter) -> Vec2;
+  fn size(&self, ctx: &PainterInstance) -> Vec2;
 }
+
+// TODO move paint_root to PaintCommand instead of separate trait?
+
+pub trait PaintRoot: PaintCommand {
+  /// Paint the root command, calling `pre_paint` before painting
+  ///
+  /// This is a convenience method for painting the root command
+  /// Do not use this inside the `paint` method of a command!
+  fn paint_root(&self, ctx: &mut PainterInstance, into: &mut PaintBuffer) {
+    self.pre_paint(ctx);
+    self.paint(ctx, into);
+  }
+}
+
+impl<T: PaintCommand> PaintRoot for T {}

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

@@ -0,0 +1,45 @@
+use crate::PainterInstance;
+
+use super::PaintCommand;
+
+pub struct PaintList {
+  pub commands: Vec<Box<dyn PaintCommand>>,
+}
+
+impl PaintList {
+  pub fn new(commands: Vec<Box<dyn PaintCommand>>) -> Self {
+    Self {
+      commands
+    }
+  }
+
+  pub fn new_empty() -> Self {
+    Self {
+      commands: Vec::new(),
+    }
+  }
+
+  pub fn add(&mut self, command: impl PaintCommand + 'static) {
+    self.commands.push(Box::new(command));
+  }
+}
+
+impl Default for PaintList {
+  fn default() -> Self {
+    Self::new_empty()
+  }
+}
+
+impl PaintCommand for PaintList {
+  fn pre_paint(&self, ctx: &mut PainterInstance) {
+    for command in &self.commands {
+      command.pre_paint(ctx);
+    }
+  }
+
+  fn paint(&self, ctx: &mut crate::PainterInstance, into: &mut crate::paint::buffer::PaintBuffer) {
+    for command in &self.commands {
+      command.paint(ctx, into);
+    }
+  }
+}

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

@@ -7,7 +7,7 @@ use crate::{
     command::PaintCommand,
   },
   texture::TextureHandle,
-  Painter
+  PainterInstance
 };
 
 /// Calculate the number of points based on the maximum corner radius
@@ -92,7 +92,7 @@ impl PaintRectangle {
 }
 
 impl PaintCommand for PaintRectangle {
-  fn paint(&self, ctx: &mut Painter, into: &mut PaintBuffer) {
+  fn paint(&self, ctx: &mut PainterInstance, into: &mut PaintBuffer) {
     // If texture is set:
     // - Get texture UV
     // - Map local UVs to texture UV coords

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

@@ -1,11 +1,11 @@
-use std::{borrow::Cow, sync::Arc};
-use fontdue::layout::{self, CoordinateSystem, GlyphRasterConfig, Layout};
+use std::borrow::Cow;
+use fontdue::layout::{CoordinateSystem, Layout};
 use glam::{vec2, Vec2};
 use crate::{
   paint::{
     buffer::PaintBuffer,
     command::PaintCommand,
-  }, text::FontHandle, Painter
+  }, text::FontHandle, PainterInstance
 };
 
 use super::Measurable;
@@ -34,7 +34,7 @@ impl PaintText {
     }
   }
 
-  fn build_font_array<'a>(&self, ctx: &'a Painter) -> Vec<&'a fontdue::Font> {
+  fn build_font_array<'a>(&self, ctx: &'a PainterInstance) -> Vec<&'a fontdue::Font> {
     let font = ctx.fonts.get_fontdue_font(self.text.font)
       .expect("FontHandle is invalid");
     vec![&font]
@@ -55,7 +55,7 @@ impl PaintText {
 }
 
 impl PaintCommand for PaintText {
-  fn pre_paint(&self, ctx: &mut Painter) {
+  fn pre_paint(&self, ctx: &mut PainterInstance) {
     let font_array = self.build_font_array(ctx);
     let layout = self.build_layout(&font_array);
 
@@ -64,7 +64,7 @@ impl PaintCommand for PaintText {
     }
   }
 
-  fn paint(&self, ctx: &mut Painter, into: &mut PaintBuffer) {
+  fn paint(&self, ctx: &mut PainterInstance, into: &mut PaintBuffer) {
     // let font_array = self.build_font_array(ctx);
     // let layout = self.build_layout(&font_array);
 
@@ -80,7 +80,7 @@ impl PaintCommand for PaintText {
 }
 
 impl Measurable for PaintText {
-  fn size(&self, ctx: &Painter) -> Vec2 {
+  fn size(&self, ctx: &PainterInstance) -> Vec2 {
     let font_array = self.build_font_array(ctx);
     let layout = self.build_layout(&font_array);
 

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

@@ -1,31 +1,27 @@
 use crate::{
-  Painter,
+  PainterInstance,
   paint::{
     buffer::PaintBuffer,
     command::PaintCommand,
   },
 };
 
-pub struct PaintTransform {
+pub struct PaintTransform<T: PaintCommand + 'static> {
   pub transform: glam::Affine2,
-  pub children: Vec<Box<dyn PaintCommand>>,
+  pub child: T,
 }
 
-impl PaintCommand for PaintTransform {
-  fn pre_paint(&self, ctx: &mut Painter) {
-    for child in &self.children {
-      child.pre_paint(ctx);
-    }
+impl<T: PaintCommand + 'static> PaintCommand for PaintTransform<T> {
+  fn pre_paint(&self, ctx: &mut PainterInstance) {
+    self.child.pre_paint(ctx);
   }
 
-  fn paint(&self, ctx: &mut Painter, into: &mut PaintBuffer) {
+  fn paint(&self, ctx: &mut PainterInstance, into: &mut PaintBuffer) {
     // remember the starting index
     let starting_index = into.vertices.len();
 
-    // paint children nodes
-    for child in &self.children {
-      child.paint(ctx, into);
-    }
+    // paint children node
+    self.child.paint(ctx, into);
 
     let mut min_point = glam::Vec2::splat(f32::MAX);
     let mut max_point = glam::Vec2::splat(f32::MIN);

hui-painter/src/text.rs

@@ -23,7 +23,7 @@ impl FontManager {
   ///
   /// Panics:
   /// - If the font data is invalid.
-  pub fn add_font(&mut self, data: &[u8]) -> FontHandle {
+  pub fn add(&mut self, data: &[u8]) -> FontHandle {
     let font = self.fonts.add_font(data);
     self.ftm.init_font(font);
     font
@@ -33,7 +33,7 @@ impl FontManager {
   ///
   /// Panics:
   /// - If the font handle is invalid.
-  pub fn remove_font(&mut self, font: FontHandle, atlas: &mut TextureAtlas) {
+  pub fn remove(&mut self, font: FontHandle, atlas: &mut TextureAtlas) {
     self.ftm.drop_font(font, atlas);
     self.fonts.remove_font(font);
   }

hui-painter/src/texture/atlas.rs

@@ -141,6 +141,9 @@ pub struct TextureAtlas {
   /// Deallocated allocations that can be reused, sorted by size
   //TODO: use binary heap or btreeset for reuse_allocations instead, but this works for now
   reuse_allocations: Vec<TextureAllocation>,
+
+  /// Version of the texture atlas, incremented every time the atlas is modified
+  version: u64,
 }
 
 impl TextureAtlas {
@@ -158,9 +161,19 @@ impl TextureAtlas {
       next_id: 0,
       allocations: HashMap::default(),
       reuse_allocations: Vec::new(),
+      version: 0,
     }
   }
 
+  pub fn version(&self) -> u64 {
+    self.version
+  }
+
+  fn mark_modified(&mut self) {
+    // XXX: wrapping_add? will this *ever* overflow?
+    self.version = self.version.wrapping_add(1);
+  }
+
   /// Get the next handle
   ///
   /// Does not allocate a texture associated with it
@@ -303,6 +316,8 @@ impl TextureAtlas {
         }
       }
     }
+
+    self.mark_modified();
   }
 
   /// Allocate a texture in the atlas, returning a handle to it.\