save settings between sessions

.gitignore

@@ -1,3 +1,4 @@
 /target
 *.png
 !images/*.png
+fractal_settings.json

Cargo.lock

@@ -1183,6 +1183,12 @@ dependencies = [
  "windows-sys 0.48.0",
 ]
 
+[[package]]
+name = "itoa"
+version = "1.0.8"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "62b02a5381cc465bd3041d84623d0fa3b66738b52b8e2fc3bab8ad63ab032f4a"
+
 [[package]]
 name = "jni"
 version = "0.21.1"
@@ -1230,6 +1236,8 @@ dependencies = [
  "eframe",
  "image",
  "native-dialog",
+ "serde",
+ "serde_json",
 ]
 
 [[package]]
@@ -1866,6 +1874,12 @@ dependencies = [
  "windows-sys 0.48.0",
 ]
 
+[[package]]
+name = "ryu"
+version = "1.0.14"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "fe232bdf6be8c8de797b22184ee71118d63780ea42ac85b61d1baa6d3b782ae9"
+
 [[package]]
 name = "same-file"
 version = "1.0.6"
@@ -1920,6 +1934,17 @@ dependencies = [
  "syn 2.0.25",
 ]
 
+[[package]]
+name = "serde_json"
+version = "1.0.102"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b5062a995d481b2308b6064e9af76011f2921c35f97b0468811ed9f6cd91dfed"
+dependencies = [
+ "itoa",
+ "ryu",
+ "serde",
+]
+
 [[package]]
 name = "serde_repr"
 version = "0.1.14"

Cargo.toml

@@ -9,6 +9,8 @@ edition = "2021"
 eframe = "0.22.0"
 image = { version = "0.24.6", default_features = false, features = ["png"] }
 native-dialog = "0.6.4"
+serde = "1.0.171"
+serde_json = "1.0.102"
 
 # Enable high optimizations for dependencies
 [profile.dev.package."*"]

src/generate.rs

@@ -1,6 +1,7 @@
 use image::{Rgb, RgbImage};
+use serde::{Deserialize, Serialize};
 
-#[derive(Clone)]
+#[derive(Clone, Serialize, Deserialize)]
 pub struct RenderOptions {
 	pub width: u32,
 	pub height: u32,
@@ -11,12 +12,26 @@ pub struct RenderOptions {
 	pub fill_style: FillStyle,
 }
 
-#[derive(PartialEq, Clone)]
+#[derive(Clone, PartialEq, Serialize, Deserialize)]
 pub enum FillStyle {
 	Bright,
 	Black,
 }
 
+impl Default for RenderOptions {
+	fn default() -> Self {
+		Self {
+			width: 512,
+			height: 512,
+			unit_width: 4.0,
+			max_iterations: 128,
+			cx: -0.8,
+			cy: -0.27,
+			fill_style: FillStyle::Bright,
+		}
+	}
+}
+
 pub fn render(q: &RenderOptions, color: (u8, u8, u8)) -> RgbImage {
 	let mut img = RgbImage::new(q.width, q.height);
 

src/main.rs

@@ -1,5 +1,10 @@
 #![windows_subsystem = "windows"]
-use std::{env, time::SystemTime};
+use std::{
+	env,
+	fs::{self, File},
+	io::Write,
+	time::SystemTime,
+};
 
 use eframe::{
 	egui::{self, DragValue, RichText, Slider, TextureOptions},
@@ -9,9 +14,12 @@ use eframe::{
 use generate::{render, FillStyle, RenderOptions};
 use image::EncodableLayout;
 use native_dialog::FileDialog;
+use serde::{Deserialize, Serialize};
 
 mod generate;
 
+const SETTINGS_FILE: &str = "fractal_settings.json";
+
 fn main() {
 	let native_options = NativeOptions {
 		initial_window_size: Some(Vec2::new(1280.0, 720.0)),
@@ -26,58 +34,77 @@ fn main() {
 	.unwrap();
 }
 
+#[derive(Serialize, Deserialize)]
 struct JuliaGUI {
 	color: (u8, u8, u8),
-	preview: TextureHandle,
+	#[serde(skip)]
+	preview: Option<TextureHandle>,
 	render_options: RenderOptions,
+	#[serde(skip)]
 	preview_render_ms: f64,
+	#[serde(skip)]
 	export_render_ms: f64,
 	export_res_multiplier: u32,
 	export_iterations: u32,
 	export_name: String,
+	#[serde(skip)]
 	settings_changed: bool,
 }
 
+impl Default for JuliaGUI {
+	fn default() -> Self {
+		Self {
+			color: (12, 5, 10),
+			preview: None,
+			render_options: RenderOptions::default(),
+			preview_render_ms: 0.0,
+			export_render_ms: f64::NAN,
+			export_res_multiplier: 8,
+			export_iterations: 512,
+			export_name: String::from("julia_fractal.png"),
+			settings_changed: true,
+		}
+	}
+}
+
 impl JuliaGUI {
 	fn new(cc: &eframe::CreationContext<'_>) -> Self {
+		let mut n: Self = fs::read_to_string(SETTINGS_FILE)
+			.map(|s| serde_json::from_str(&s).ok())
+			.ok()
+			.flatten()
+			.unwrap_or_default();
+
 		let preview = cc.egui_ctx.load_texture(
 			"preview_image",
 			egui::ColorImage::from_rgb([1, 1], &[0, 0, 0]),
 			TextureOptions::default(),
 		);
-		let preview_quality = RenderOptions {
-			width: 512,
-			height: 512,
-			unit_width: 4.0,
-			max_iterations: 128,
-			cx: -0.981,
-			cy: -0.277,
-			fill_style: FillStyle::Bright,
-		};
 
-		Self {
-			color: (12, 5, 10),
-			preview,
-			render_options: preview_quality,
-			preview_render_ms: 0.0,
-			export_render_ms: f64::NAN,
-			export_res_multiplier: 8,
-			export_iterations: 512,
-			export_name: String::from("julia_set.png"),
-			settings_changed: true,
-		}
+		n.preview = Some(preview);
+		n.settings_changed = true;
+		n
+	}
+
+	fn save_settings(&self) {
+		let settings = serde_json::to_string_pretty(&self).unwrap();
+		let mut file = File::create(SETTINGS_FILE).unwrap();
+		file.write_all(settings.as_bytes()).unwrap();
 	}
 
 	fn update_preview(&mut self) {
 		let start_time = SystemTime::now();
-		let preview = render(&self.render_options, self.color);
-		self.preview.set(
-			egui::ColorImage::from_rgb(
-				[preview.width() as usize, preview.height() as usize],
-				preview.as_bytes(),
-			),
-			TextureOptions::default(),
-		);
+		let frame = render(&self.render_options, self.color);
+
+		if let Some(preview) = &mut self.preview {
+			preview.set(
+				egui::ColorImage::from_rgb(
+					[frame.width() as usize, frame.height() as usize],
+					frame.as_bytes(),
+				),
+				TextureOptions::default(),
+			);
+		}
 		self.preview_render_ms = start_time.elapsed().unwrap().as_micros() as f64 / 1000.0;
 	}
 
@@ -94,6 +121,7 @@ impl JuliaGUI {
 			println!("Error exporting render: {err}");
 		}
 		self.export_render_ms = start_time.elapsed().unwrap().as_micros() as f64 / 1000.0;
+		self.save_settings();
 	}
 }
 
@@ -101,6 +129,7 @@ impl eframe::App for JuliaGUI {
 	fn update(&mut self, ctx: &egui::Context, _frame: &mut Frame) {
 		if self.settings_changed {
 			self.update_preview();
+			self.save_settings();
 			self.settings_changed = false;
 		}
 
@@ -152,11 +181,15 @@ impl eframe::App for JuliaGUI {
 				ui.label("Preview resolution:");
 				ui.horizontal(|ui| {
 					let set_width = ui.add(
-						DragValue::new(&mut self.render_options.width).clamp_range(128..=16384),
+						DragValue::new(&mut self.render_options.width)
+							.clamp_range(128..=4096)
+							.suffix("px"),
 					);
 					ui.label("x");
 					let set_height = ui.add(
-						DragValue::new(&mut self.render_options.height).clamp_range(128..=16384),
+						DragValue::new(&mut self.render_options.height)
+							.clamp_range(128..=4096)
+							.suffix("px"),
 					);
 					if set_width.changed() || set_height.changed() {
 						self.settings_changed = true;
@@ -207,9 +240,13 @@ impl eframe::App for JuliaGUI {
 			});
 
 		egui::CentralPanel::default().show(ctx, |ui| {
-			ui.image(&self.preview, self.preview.size_vec2());
+			if let Some(texture) = &self.preview {
+				ui.image(texture, texture.size_vec2());
+			}
 		});
 	}
 
-	fn on_exit(&mut self, _gl: Option<&eframe::glow::Context>) {}
+	fn on_exit(&mut self, _gl: Option<&eframe::glow::Context>) {
+		self.save_settings()
+	}
 }