Built an app builder and other minor things

diff --git a/Cargo.lock b/Cargo.lock
index 7de4beb..55e8342 100644 (file)
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -2,300 +2,286 @@
 # It is not intended for manual editing.
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-"checksum semver-parser 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)" = "388a1df253eca08550bef6c72392cfe7c30914bf41df5269b68cbd6ff8f570a3"
-"checksum time 0.1.42 (registry+https://github.com/rust-lang/crates.io-index)" = "db8dcfca086c1143c9270ac42a2bbd8a7ee477b78ac8e45b19abfb0cbede4b6f"
-"checksum winapi 0.3.6 (registry+https://github.com/rust-lang/crates.io-index)" = "92c1eb33641e276cfa214a0522acad57be5c56b10cb348b3c5117db75f3ac4b0"
-"checksum winapi-i686-pc-windows-gnu 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)" = "ac3b87c63620426dd9b991e5ce0329eff545bccbbb34f3be09ff6fb6ab51b7b6"
-"checksum winapi-x86_64-pc-windows-gnu 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)" = "712e227841d057c1ee1cd2fb22fa7e5a5461ae8e48fa2ca79ec42cfc1931183f"
+checksum = "712e227841d057c1ee1cd2fb22fa7e5a5461ae8e48fa2ca79ec42cfc1931183f"

diff --git a/src/common.rs b/src/common.rs
index 6f000d8..f5ebb6e 100644 (file)
--- a/src/common.rs
+++ b/src/common.rs
@@ -1,4 +1,4 @@
-use std::ops::{Add, AddAssign};
+use std::ops::{Add, AddAssign, Mul};
 
 #[macro_export]
 macro_rules! point {
@@ -32,6 +32,25 @@ impl<T: AddAssign> AddAssign for Point2D<T> {
     }
 }
 
+#[derive(Default)]
+pub struct Rect<T> {
+    pub width: T,
+    pub height: T,
+}
+
+impl<T: Mul<Output=T> + Copy> Rect<T> {
+    #[allow(dead_code)]
+    pub fn area(&self) -> T {
+       self.width * self.height
+    }
+}
+
+impl<T> From<(T, T)> for Rect<T> {
+    fn from(item: (T, T)) -> Self {
+       Rect { width: item.0, height: item.1 }
+    }
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;
@@ -52,4 +71,11 @@ mod tests {
         a += point!(2, 2); // AddAssign
         assert_eq!(a, point!(3, 2));
     }
+
+    #[test]
+    fn area_for_rect_of_multipliable_type() {
+        let r: Rect<_> = (30, 20).into(); // the Into trait uses the From trait
+       assert_eq!(r.area(), 30 * 20);
+        // let a = Rect::from(("a".to_string(), "b".to_string())).area(); // this doesn't work, because area() is not implemented for String
+    }
 }

diff --git a/src/game/app.rs b/src/game/app.rs
index 50acaa1..b37e8fd 100644 (file)
--- a/src/game/app.rs
+++ b/src/game/app.rs
@@ -9,44 +9,83 @@ use sdl2::video::Window;
 
 use ::{SCREEN_HEIGHT, SCREEN_WIDTH};
 use boll::*;
-use common::Point2D;
+use common::{Point2D, Rect};
 use sprites::SpriteManager;
 use NS_PER_FRAME;
 use point; // defined in common, but loaded from main...
 
 pub type Nanoseconds = u64;
 
-pub struct App {
-    pub canvas: Canvas<Window>,
-    pub event_pump: EventPump,
-    pub sprites: SpriteManager,
-    pub state: Box<dyn AppState>,
+#[derive(Default)]
+pub struct AppBuilder {
+    resolution: Rect<u16>,
+    fps: u8,
+    state: Option<Box<dyn AppState>>,
+    title: Option<String>,
 }
 
-impl App {
-    pub fn new() -> App {
+impl AppBuilder {
+    pub fn with_resolution(mut self, width: u16, height: u16) -> Self {
+       self.resolution = Rect { width, height };
+       self
+    }
+
+    pub fn with_fps(mut self, fps: u8) -> Self {
+       unimplemented!()
+       // self.fps = fps;
+       // self
+    }
+
+    pub fn with_state(mut self, state: Box<dyn AppState>) -> Self {
+       self.state = Some(state);
+       self
+    }
+
+    pub fn with_title(mut self, title: &str) -> Self {
+       self.title = Some(title.to_string());
+       self
+    }
+
+    pub fn start(self) -> App {
         let context = sdl2::init().unwrap();
         sdl2::image::init(sdl2::image::InitFlag::PNG).unwrap();
-        let window = context.video().unwrap().window("SDL test", SCREEN_WIDTH, SCREEN_HEIGHT)
+        let window = context
+           .video().unwrap()
+           .window(&self.title.unwrap(), self.resolution.width.into(), self.resolution.height.into())
             .position_centered()
             .opengl()
-            .build()
-            .unwrap();
+            .build().unwrap();
         context.mouse().show_cursor(false);
+
         let mut canvas = window.into_canvas().build().unwrap();
         canvas.set_blend_mode(BlendMode::Add);
         canvas.set_draw_color(Color::RGB(0, 0, 0));
         canvas.clear();
         canvas.present();
+
         let event_pump = context.event_pump().unwrap();
         let sprites = SpriteManager::new(canvas.texture_creator());
+
         App {
             canvas,
             event_pump,
             sprites,
-            state: Box::new(ActiveState::new()),
+            state: self.state.unwrap_or(Box::new(ActiveState::new())),
         }
     }
+}
+
+pub struct App {
+    pub canvas: Canvas<Window>,
+    pub event_pump: EventPump,
+    pub sprites: SpriteManager,
+    pub state: Box<dyn AppState>,
+}
+
+impl App {
+    pub fn new() -> AppBuilder {
+       Default::default()
+    }
 
     pub fn load_sprites(&mut self, sprites: &[(&str, &str)]) {
         for (name, file) in sprites {
@@ -70,7 +109,7 @@ pub struct ActiveState {
 }
 
 impl ActiveState {
-    fn new() -> ActiveState {
+    pub fn new() -> ActiveState {
         ActiveState {
             bolls: Bollar::new(),
             boll_size: 1,

diff --git a/src/main.rs b/src/main.rs
index fdd36da..31f9d3b 100644 (file)
--- a/src/main.rs
+++ b/src/main.rs
@@ -28,7 +28,12 @@ const NS_PER_FRAME: u32 = 1_000_000_000 / FPS;
 
 fn main() {
     println!("starting...");
-    let mut app = App::new();
+    let mut app = App::new()
+       .with_resolution(SCREEN_WIDTH as u16, SCREEN_HEIGHT as u16)
+       .with_fps(60)
+       .with_state(Box::new(ActiveState::new()))
+       .with_title("SDL test")
+       .start();
     app.load_sprites(&[
         ("block", "res/block.bmp"),
         ("mario", "res/mario-trans.png"),