[eframe] Make persistence, http and time optional features

Saves on compile times.

egui_demo_lib/Cargo.toml

@@ -15,18 +15,24 @@ include = [ "**/*.rs", "Cargo.toml"]
 [lib]
 
 [dependencies]
-egui = { version = "0.6.0", path = "../egui", features = ["serde"] }
-epi = { version = "0.6.0", path = "../epi", features = ["serde", "serde_json"] }
-serde = { version = "1", features = ["derive"] }
-serde_json = "1"
+egui = { version = "0.6.0", path = "../egui" }
+epi = { version = "0.6.0", path = "../epi" }
 
-# Http fetch app:
-image = { version = "0.23", default_features = false, features = ["jpeg", "png"] }
-syntect = { version = "4", default_features = false, features = ["default-fancy"] }
+# feature "http":
+image = { version = "0.23", default_features = false, features = ["jpeg", "png"], optional = true }
+syntect = { version = "4", default_features = false, features = ["default-fancy"], optional = true }
+
+# feature "persistence":
+serde = { version = "1", features = ["derive"], optional = true }
 
 [dev-dependencies]
 criterion = { version = "0.3", default-features = false }
 
+[features]
+default = []
+http = ["image", "syntect", "epi/http"]
+persistence = ["epi/persistence", "serde"]
+
 [[bench]]
 name = "benchmark"
 harness = false

egui_demo_lib/src/apps/color_test.rs

@@ -9,9 +9,9 @@ const RED: Color32 = Color32::RED;
 const TRANSPARENT: Color32 = Color32::TRANSPARENT;
 const WHITE: Color32 = Color32::WHITE;
 
-#[derive(serde::Deserialize, serde::Serialize)]
+#[cfg_attr(feature = "persistence", derive(serde::Deserialize, serde::Serialize))]
 pub struct ColorTest {
-    #[serde(skip)]
+    #[cfg_attr(feature = "persistence", serde(skip))]
     tex_mngr: TextureManager,
     vertex_gradients: bool,
     texture_gradients: bool,

egui_demo_lib/src/apps/demo/app.rs

@@ -2,8 +2,9 @@
 ///
 /// Implements `epi::App` so it can be used with
 /// [`egui_glium`](https://crates.io/crates/egui_glium) and [`egui_web`](https://crates.io/crates/egui_web).
-#[derive(Default, serde::Deserialize, serde::Serialize)]
-#[serde(default)]
+#[derive(Default)]
+#[cfg_attr(feature = "persistence", derive(serde::Deserialize, serde::Serialize))]
+#[cfg_attr(feature = "persistence", serde(default))]
 pub struct DemoApp {
     demo_windows: super::DemoWindows,
 }
@@ -13,10 +14,12 @@ impl epi::App for DemoApp {
         "✨ Egui Demo"
     }
 
+    #[cfg(feature = "persistence")]
     fn load(&mut self, storage: &dyn epi::Storage) {
         *self = epi::get_value(storage, epi::APP_KEY).unwrap_or_default()
     }
 
+    #[cfg(feature = "persistence")]
     fn save(&mut self, storage: &mut dyn epi::Storage) {
         epi::set_value(storage, epi::APP_KEY, self);
     }

egui_demo_lib/src/apps/demo/dancing_strings.rs

@@ -1,7 +1,7 @@
 use egui::{containers::*, *};
 
-#[derive(serde::Deserialize, serde::Serialize)]
-#[serde(default)]
+#[cfg_attr(feature = "persistence", derive(serde::Deserialize, serde::Serialize))]
+#[cfg_attr(feature = "persistence", serde(default))]
 pub struct DancingStrings {}
 
 impl Default for DancingStrings {

egui_demo_lib/src/apps/demo/demo_window.rs

@@ -2,8 +2,8 @@ use super::*;
 use egui::{color::*, *};
 
 /// Showcase some ui code
-#[derive(serde::Deserialize, serde::Serialize)]
-#[serde(default)]
+#[cfg_attr(feature = "persistence", derive(serde::Deserialize, serde::Serialize))]
+#[cfg_attr(feature = "persistence", serde(default))]
 pub struct DemoWindow {
     num_columns: usize,
 
@@ -106,8 +106,9 @@ impl DemoWindow {
 
 // ----------------------------------------------------------------------------
 
-#[derive(PartialEq, serde::Deserialize, serde::Serialize)]
-#[serde(default)]
+#[derive(PartialEq)]
+#[cfg_attr(feature = "persistence", derive(serde::Deserialize, serde::Serialize))]
+#[cfg_attr(feature = "persistence", serde(default))]
 struct ColorWidgets {
     srgba_unmul: [u8; 4],
     srgba_premul: [u8; 4],
@@ -176,8 +177,8 @@ impl ColorWidgets {
 
 // ----------------------------------------------------------------------------
 
-#[derive(serde::Deserialize, serde::Serialize)]
-#[serde(default)]
+#[cfg_attr(feature = "persistence", derive(serde::Deserialize, serde::Serialize))]
+#[cfg_attr(feature = "persistence", serde(default))]
 struct BoxPainting {
     size: Vec2,
     corner_radius: f32,
@@ -220,8 +221,8 @@ impl BoxPainting {
 
 // ----------------------------------------------------------------------------
 
-#[derive(serde::Deserialize, serde::Serialize)]
-#[serde(default)]
+#[cfg_attr(feature = "persistence", derive(serde::Deserialize, serde::Serialize))]
+#[cfg_attr(feature = "persistence", serde(default))]
 struct LayoutDemo {
     // Identical to contents of `egui::Layout`
     main_dir: Direction,
@@ -363,7 +364,8 @@ enum Action {
     Delete,
 }
 
-#[derive(Clone, Default, serde::Deserialize, serde::Serialize)]
+#[derive(Clone, Default)]
+#[cfg_attr(feature = "persistence", derive(serde::Deserialize, serde::Serialize))]
 struct Tree(Vec<Tree>);
 
 impl Tree {

egui_demo_lib/src/apps/demo/demo_windows.rs

@@ -2,11 +2,11 @@ use egui::{CtxRef, Resize, ScrollArea, Ui, Window};
 
 // ----------------------------------------------------------------------------
 
-#[derive(serde::Deserialize, serde::Serialize)]
-#[serde(default)]
+#[cfg_attr(feature = "persistence", derive(serde::Deserialize, serde::Serialize))]
+#[cfg_attr(feature = "persistence", serde(default))]
 struct Demos {
     /// open, view
-    #[serde(skip)] // TODO: serialize the `open` state.
+    #[cfg_attr(feature = "persistence", serde(skip))] // TODO: serialize the `open` state.
     demos: Vec<(bool, Box<dyn super::Demo>)>,
 }
 impl Default for Demos {
@@ -40,8 +40,9 @@ impl Demos {
 // ----------------------------------------------------------------------------
 
 /// A menu bar in which you can select different demo windows to show.
-#[derive(Default, serde::Deserialize, serde::Serialize)]
-#[serde(default)]
+#[derive(Default)]
+#[cfg_attr(feature = "persistence", derive(serde::Deserialize, serde::Serialize))]
+#[cfg_attr(feature = "persistence", serde(default))]
 pub struct DemoWindows {
     open_windows: OpenWindows,
 
@@ -189,7 +190,7 @@ impl DemoWindows {
 
 // ----------------------------------------------------------------------------
 
-#[derive(serde::Deserialize, serde::Serialize)]
+#[cfg_attr(feature = "persistence", derive(serde::Deserialize, serde::Serialize))]
 struct OpenWindows {
     demo: bool,
 

egui_demo_lib/src/apps/demo/painting.rs

@@ -1,7 +1,7 @@
 use egui::*;
 
-#[derive(serde::Deserialize, serde::Serialize)]
-#[serde(default)]
+#[cfg_attr(feature = "persistence", derive(serde::Deserialize, serde::Serialize))]
+#[cfg_attr(feature = "persistence", serde(default))]
 pub struct Painting {
     lines: Vec<Vec<Vec2>>,
     stroke: Stroke,

egui_demo_lib/src/apps/demo/scrolls.rs

@@ -1,7 +1,7 @@
 use egui::{color::*, *};
 
-#[derive(serde::Deserialize, serde::Serialize)]
-#[serde(default)]
+#[cfg_attr(feature = "persistence", derive(serde::Deserialize, serde::Serialize))]
+#[cfg_attr(feature = "persistence", serde(default))]
 pub struct Scrolls {
     track_item: usize,
     tracking: bool,

egui_demo_lib/src/apps/demo/sliders.rs

@@ -2,8 +2,9 @@ use egui::*;
 use std::f64::INFINITY;
 
 /// Showcase sliders
-#[derive(PartialEq, serde::Deserialize, serde::Serialize)]
-#[serde(default)]
+#[derive(PartialEq)]
+#[cfg_attr(feature = "persistence", derive(serde::Deserialize, serde::Serialize))]
+#[cfg_attr(feature = "persistence", serde(default))]
 pub struct Sliders {
     pub min: f64,
     pub max: f64,

egui_demo_lib/src/apps/demo/widgets.rs

@@ -1,6 +1,7 @@
 use egui::{color::*, *};
 
-#[derive(Debug, PartialEq, serde::Deserialize, serde::Serialize)]
+#[derive(Debug, PartialEq)]
+#[cfg_attr(feature = "persistence", derive(serde::Deserialize, serde::Serialize))]
 enum Enum {
     First,
     Second,
@@ -13,8 +14,8 @@ impl Default for Enum {
     }
 }
 
-#[derive(serde::Deserialize, serde::Serialize)]
-#[serde(default)]
+#[cfg_attr(feature = "persistence", derive(serde::Deserialize, serde::Serialize))]
+#[cfg_attr(feature = "persistence", serde(default))]
 pub struct Widgets {
     button_enabled: bool,
     count: usize,

egui_demo_lib/src/apps/demo/window_options.rs

@@ -1,6 +1,7 @@
 use crate::__egui_github_link_file;
 
-#[derive(Clone, PartialEq, serde::Deserialize, serde::Serialize)]
+#[derive(Clone, PartialEq)]
+#[cfg_attr(feature = "persistence", derive(serde::Deserialize, serde::Serialize))]
 pub struct WindowOptions {
     title: String,
     title_bar: bool,

egui_demo_lib/src/apps/fractal_clock.rs

@@ -1,8 +1,9 @@
 use egui::{containers::*, widgets::*, *};
 use std::f32::consts::TAU;
 
-#[derive(PartialEq, serde::Deserialize, serde::Serialize)]
-#[serde(default)]
+#[derive(PartialEq)]
+#[cfg_attr(feature = "persistence", derive(serde::Deserialize, serde::Serialize))]
+#[cfg_attr(feature = "persistence", serde(default))]
 pub struct FractalClock {
     paused: bool,
     time: f64,

egui_demo_lib/src/apps/http_app.rs

@@ -30,17 +30,17 @@ impl Resource {
     }
 }
 
-#[derive(serde::Deserialize, serde::Serialize)]
+#[cfg_attr(feature = "persistence", derive(serde::Deserialize, serde::Serialize))]
 pub struct HttpApp {
     url: String,
 
-    #[serde(skip)]
+    #[cfg_attr(feature = "persistence", serde(skip))]
     in_progress: Option<Receiver<Result<Response, String>>>,
 
-    #[serde(skip)]
+    #[cfg_attr(feature = "persistence", serde(skip))]
     result: Option<Result<Resource, String>>,
 
-    #[serde(skip)]
+    #[cfg_attr(feature = "persistence", serde(skip))]
     tex_mngr: TexMngr,
 }
 

egui_demo_lib/src/apps/mod.rs

@@ -1,11 +1,13 @@
 mod color_test;
 mod demo;
 mod fractal_clock;
+#[cfg(feature = "http")]
 mod http_app;
 
 pub use color_test::ColorTest;
 pub use demo::DemoApp;
 pub use fractal_clock::FractalClock;
+#[cfg(feature = "http")]
 pub use http_app::HttpApp;
 
 pub use demo::DemoWindows; // used for tests

egui_demo_lib/src/wrap_app.rs

@@ -1,8 +1,10 @@
 /// All the different demo apps.
-#[derive(Default, serde::Deserialize, serde::Serialize)]
-#[serde(default)]
+#[derive(Default)]
+#[cfg_attr(feature = "persistence", derive(serde::Deserialize, serde::Serialize))]
+#[cfg_attr(feature = "persistence", serde(default))]
 pub struct Apps {
     demo: crate::apps::DemoApp,
+    #[cfg(feature = "http")]
     http: crate::apps::HttpApp,
     clock: crate::apps::FractalClock,
     color_test: crate::apps::ColorTest,
@@ -12,6 +14,7 @@ impl Apps {
     fn iter_mut(&mut self) -> impl Iterator<Item = (&str, &mut dyn epi::App)> {
         vec![
             ("demo", &mut self.demo as &mut dyn epi::App),
+            #[cfg(feature = "http")]
             ("http", &mut self.http as &mut dyn epi::App),
             ("clock", &mut self.clock as &mut dyn epi::App),
             ("colors", &mut self.color_test as &mut dyn epi::App),
@@ -21,8 +24,9 @@ impl Apps {
 }
 
 /// Wraps many demo/test apps into one.
-#[derive(Default, serde::Deserialize, serde::Serialize)]
-#[serde(default)]
+#[derive(Default)]
+#[cfg_attr(feature = "persistence", derive(serde::Deserialize, serde::Serialize))]
+#[cfg_attr(feature = "persistence", serde(default))]
 pub struct WrapApp {
     selected_anchor: String,
     apps: Apps,
@@ -34,10 +38,12 @@ impl epi::App for WrapApp {
         "Egui Demo Apps"
     }
 
+    #[cfg(feature = "persistence")]
     fn load(&mut self, storage: &dyn epi::Storage) {
         *self = epi::get_value(storage, epi::APP_KEY).unwrap_or_default()
     }
 
+    #[cfg(feature = "persistence")]
     fn save(&mut self, storage: &mut dyn epi::Storage) {
         epi::set_value(storage, epi::APP_KEY, self);
     }
@@ -167,18 +173,20 @@ impl Default for RunMode {
 
 // ----------------------------------------------------------------------------
 
-#[derive(Default, serde::Deserialize, serde::Serialize)]
-#[serde(default)]
+#[derive(Default)]
+#[cfg_attr(feature = "persistence", derive(serde::Deserialize, serde::Serialize))]
+#[cfg_attr(feature = "persistence", serde(default))]
 struct BackendPanel {
     open: bool,
 
-    #[serde(skip)] // go back to `Reactive` mode each time we start
+    #[cfg_attr(feature = "persistence", serde(skip))]
+    // go back to `Reactive` mode each time we start
     run_mode: RunMode,
 
     /// current slider value for current gui scale
     pixels_per_point: Option<f32>,
 
-    #[serde(skip)]
+    #[cfg_attr(feature = "persistence", serde(skip))]
     frame_history: crate::frame_history::FrameHistory,
 }