Starting builder pattern for Camera

I'm going to change the Camera construction to use the builder pattern.
This means I need to implement trait Default for Camera, and then a
bunch of functions for setting the properties.

Cargo.toml

@@ -5,6 +5,15 @@ edition = "2021"
 
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
+[[bin]]
+name = "rustpt_cli"
+path = "src/cli_tool.rs"
+
+[[bin]]
+name = "rustpt_gui"
+path = "src/gui_tool.rs"
+
 [dependencies]
 rand = { version = "0.8.5", features = ["small_rng"] }
 itertools = { version = "0.11.0" }
+eframe = "0.25.0"

src/cli_tool.rs

@@ -1,18 +1,14 @@
-
-mod primitives;
-mod scene;
-mod renderer;
-
-use crate::primitives::{
+#![warn(clippy::all, rust_2018_idioms, rust_2018_compatibility)]
+use rustpt::primitives::{
     Vec2i,
     Vec3,
 };
-use crate::scene::{
+use rustpt::scene::{
     Camera,
     Scene
 };
 
-use crate::renderer::{
+use rustpt::renderer::{
     Tile,
     RenderProperties,
 };

src/gui_tool.rs

@@ -0,0 +1,36 @@
+#![warn(clippy::all, rust_2018_idioms)]
+use eframe::{egui, Frame};
+
+fn main() -> Result<(), eframe::Error> {
+    let options = eframe::NativeOptions {
+        viewport: egui::ViewportBuilder::default()
+            .with_inner_size([800.0, 600.0])
+            .with_min_inner_size([50.0, 50.0])
+            .with_title("RustPT GUI Tool"),
+            ..Default::default()
+    };
+    eframe::run_native(
+        "app name?",
+        options,
+    Box::new(
+        | cc | Box::new(RtApp::new(cc))
+    ))
+}
+
+#[derive(Default)]
+struct RtApp;
+
+impl RtApp {
+    fn new(cc: &eframe::CreationContext<'_>) -> Self {
+        Self::default()
+    }
+}
+
+impl eframe::App for RtApp {
+    fn update(&mut self, ctx: &egui::Context, frame: &mut Frame) {
+        egui::SidePanel::left("Render Properties").show(ctx, |ui| {
+            ui.heading("Render Properties");
+            ui.label("")
+        });
+    }
+}

src/lib.rs

@@ -0,0 +1,4 @@
+#![warn(clippy::all, rust_2018_idioms, rust_2018_compatibility)]
+pub mod primitives;
+pub mod scene;
+pub mod renderer;

src/primitives.rs

@@ -101,7 +101,7 @@ where T: std::ops::Div<Output = T>{
 
 impl <T> Display for Vec2<T> 
 where T: Display { // nested type still needs to have Display
-    fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result {
+    fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result {
         let str = format!("{} {}", self.x, self.y);
         fmt.write_str(&str)
     }
@@ -370,7 +370,7 @@ impl Neg for Vec3{
 }
 
 impl Display for Vec3 {
-	fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result {
+	fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result {
 		let str = format!("{} {} {}", self.x, self.y, self.z);
 		fmt.write_str(&str)?;
 		Ok(())

src/scene.rs

@@ -179,15 +179,37 @@ pub struct Camera {
 }
 
 impl Camera {
-    pub fn new(
-        lookfrom: Vec3,
-        lookat: Vec3,
-        vup: Vec3,
-        vfov: f32,
-        aspect_ratio: f32,
-        aperture: f32,
-        focus_dist: f32
-    ) -> Camera {
+    pub fn new() -> Camera {
+        Self::default()
+    }
+
+    pub fn get_ray(&self, s: f32, t: f32, srng: &mut SmallRng) -> Ray {
+        let rd = Vec3::rand_in_unit_disk(srng) * self.lens_radius;
+        let offset = self.u * rd.x + self.v * rd.y;
+
+        let dir = self.lower_left_corner
+                + self.horizontal * s
+                + self.vertical * t 
+                - self.origin - offset;
+        Ray{
+            orig: self.origin + offset,
+            dir,
+        }
+    }
+}
+
+impl Default for Camera {
+    fn default() -> Self {
+        // defaults are the same as the hard-coded properties passed from main
+        // ... except for the `lookfrom` position: (13.0, 2.0, 3.0) became (10.0, 0..)
+        let lookfrom = Vec3::new(10.0, 0.0, 0.0);
+        let lookat = Vec3 { x: 1.0, y: 0.0, z: 0.0 };
+        let vup = Vec3::new(0.0, 1.0, 0.0);
+        let vfov = 20.0;
+        let aspect_ratio = 3.0 / 2.0;
+        let aperture = 0.1;
+        let focus_dist = 10.0;
+
         let theta = degrees_to_radians(vfov);
         let h = (theta / 2.0).tan();
         let vp_height = 2.0 * h;
@@ -211,20 +233,6 @@ impl Camera {
             lens_radius: aperture / 2.0,
         }
     }
-
-    pub fn get_ray(&self, s: f32, t: f32, srng: &mut SmallRng) -> Ray {
-        let rd = Vec3::rand_in_unit_disk(srng) * self.lens_radius;
-        let offset = self.u * rd.x + self.v * rd.y;
-
-        let dir = self.lower_left_corner
-                + self.horizontal * s
-                + self.vertical * t 
-                - self.origin - offset;
-        Ray{
-            orig: self.origin + offset,
-            dir,
-        }
-    }
 }