From cf241f1fc4b11007cdd2c0a908f25fbfc5ee9cd1 Mon Sep 17 00:00:00 2001
From: Ryan Butler <thebutlah@gmail.com>
Date: Sat, 7 Oct 2023 17:20:31 +0200
Subject: [PATCH] Simplify extraction by using derive (#211)

---
 src/egui_node.rs      |  5 ++---
 src/lib.rs            | 17 +++++++++++------
 src/render_systems.rs | 22 ++--------------------
 3 files changed, 15 insertions(+), 29 deletions(-)

diff --git a/src/egui_node.rs b/src/egui_node.rs
index bb7a8c644..ebe0b67c9 100644
--- a/src/egui_node.rs
+++ b/src/egui_node.rs
@@ -1,9 +1,8 @@
 use crate::{
     render_systems::{
         EguiPipelines, EguiTextureBindGroups, EguiTextureId, EguiTransform, EguiTransforms,
-        ExtractedEguiSettings,
     },
-    EguiRenderOutput, WindowSize,
+    EguiRenderOutput, EguiSettings, WindowSize,
 };
 use bevy::{
     core::cast_slice,
@@ -199,7 +198,7 @@ impl Node for EguiNode {
         let window_size = *window_size;
         let paint_jobs = std::mem::take(&mut render_output.paint_jobs);
 
-        let egui_settings = &world.get_resource::<ExtractedEguiSettings>().unwrap();
+        let egui_settings = &world.get_resource::<EguiSettings>().unwrap();
 
         let render_device = world.get_resource::<RenderDevice>().unwrap();
 
diff --git a/src/lib.rs b/src/lib.rs
index 8f131a9ca..f5d5d8fd5 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -83,6 +83,8 @@ use bevy::{
         Shader, SystemSet, With, Without,
     },
     render::{
+        extract_component::{ExtractComponent, ExtractComponentPlugin},
+        extract_resource::{ExtractResource, ExtractResourcePlugin},
         render_resource::{AddressMode, SamplerDescriptor, SpecializedRenderPipelines},
         texture::{Image, ImageSampler},
         ExtractSchedule, Render, RenderApp, RenderSet,
@@ -100,7 +102,7 @@ use thread_local::ThreadLocal;
 pub struct EguiPlugin;
 
 /// A resource for storing global UI settings.
-#[derive(Clone, Debug, Resource)]
+#[derive(Clone, Debug, Resource, ExtractResource)]
 pub struct EguiSettings {
     /// Global scale factor for Egui widgets (`1.0` by default).
     ///
@@ -255,7 +257,7 @@ impl EguiClipboard {
 }
 
 /// Is used for storing Egui shapes and textures delta.
-#[derive(Component, Clone, Default, Debug, Resource)]
+#[derive(Component, Clone, Default, Debug, ExtractComponent)]
 pub struct EguiRenderOutput {
     /// Pairs of rectangles and paint commands.
     ///
@@ -274,7 +276,7 @@ pub struct EguiOutput {
 }
 
 /// A component for storing `bevy_egui` context.
-#[derive(Clone, Component, Default)]
+#[derive(Clone, Component, Default, ExtractComponent)]
 pub struct EguiContext(egui::Context);
 
 impl EguiContext {
@@ -510,7 +512,7 @@ impl EguiUserTextures {
 }
 
 /// Stores physical size and scale factor, is used as a helper to calculate logical size.
-#[derive(Component, Debug, Default, Clone, Copy, PartialEq)]
+#[derive(Component, Debug, Default, Clone, Copy, PartialEq, ExtractComponent)]
 pub struct WindowSize {
     physical_width: f32,
     physical_height: f32,
@@ -577,6 +579,10 @@ impl Plugin for EguiPlugin {
         world.init_resource::<EguiUserTextures>();
         world.init_resource::<EguiMousePosition>();
         world.insert_resource(TouchId::default());
+        app.add_plugins(ExtractResourcePlugin::<EguiSettings>::default());
+        app.add_plugins(ExtractComponentPlugin::<EguiContext>::default());
+        app.add_plugins(ExtractComponentPlugin::<WindowSize>::default());
+        app.add_plugins(ExtractComponentPlugin::<EguiRenderOutput>::default());
 
         app.add_systems(
             PreStartup,
@@ -645,9 +651,8 @@ impl Plugin for EguiPlugin {
                 .add_systems(
                     ExtractSchedule,
                     (
-                        render_systems::extract_egui_render_data_system,
-                        render_systems::extract_egui_textures_system,
                         render_systems::setup_new_windows_render_system,
+                        render_systems::extract_egui_textures_system,
                     )
                         .into_configs(),
                 )
diff --git a/src/render_systems.rs b/src/render_systems.rs
index 51e2a7911..eb2136b8f 100644
--- a/src/render_systems.rs
+++ b/src/render_systems.rs
@@ -1,6 +1,6 @@
 use crate::{
     egui_node::{EguiNode, EguiPipeline, EguiPipelineKey},
-    EguiContextQueryReadOnly, EguiManagedTextures, EguiSettings, EguiUserTextures, WindowSize,
+    EguiManagedTextures, EguiSettings, EguiUserTextures, WindowSize,
 };
 use bevy::{
     asset::HandleId,
@@ -21,10 +21,6 @@ use bevy::{
     utils::HashMap,
 };
 
-/// Extracted Egui settings.
-#[derive(Resource, Deref, DerefMut, Default)]
-pub struct ExtractedEguiSettings(pub EguiSettings);
-
 /// Corresponds to Egui's [`egui::TextureId`].
 #[derive(Debug, PartialEq, Eq, Hash)]
 pub enum EguiTextureId {
@@ -78,20 +74,6 @@ pub fn setup_new_windows_render_system(
     }
 }
 
-/// Extracts Egui context, render output, settings and application window sizes.
-pub fn extract_egui_render_data_system(
-    mut commands: Commands,
-    egui_settings: Extract<Res<EguiSettings>>,
-    contexts: Extract<Query<EguiContextQueryReadOnly>>,
-) {
-    commands.insert_resource(ExtractedEguiSettings(egui_settings.clone()));
-    for context in contexts.iter() {
-        commands
-            .get_or_spawn(context.window_entity)
-            .insert((*context.window_size, context.render_output.clone()));
-    }
-}
-
 /// Extracts Egui textures.
 pub fn extract_egui_textures_system(
     mut commands: Commands,
@@ -147,7 +129,7 @@ impl EguiTransform {
 pub fn prepare_egui_transforms_system(
     mut egui_transforms: ResMut<EguiTransforms>,
     window_sizes: Query<(Entity, &WindowSize)>,
-    egui_settings: Res<ExtractedEguiSettings>,
+    egui_settings: Res<EguiSettings>,
 
     render_device: Res<RenderDevice>,
     render_queue: Res<RenderQueue>,