Use trait for boll variants

[kaka/rust-sdl-test.git] / src / boll.rs

diff --git a/src/boll.rs b/src/boll.rs
index b273f1d..f936fca 100644 (file)
--- a/src/boll.rs
+++ b/src/boll.rs
@@ -7,13 +7,18 @@ use sdl2::video::Window;
 use {SCREEN_HEIGHT, SCREEN_WIDTH};
 use common::Point2D;
 
-pub struct Boll {
+pub trait Boll {
+    fn update(&mut self);
+    fn draw(&mut self, canvas: &mut Canvas<Window>, size: u32);
+}
+
+pub struct SquareBoll {
     pub pos: Point2D<f64>,
     pub vel: Point2D<f64>,
 }
 
-impl Boll {
-    pub fn update(&mut self) {
+impl Boll for SquareBoll {
+    fn update(&mut self) {
         self.vel.y += 0.1;
         self.pos += self.vel;
 
@@ -35,7 +40,7 @@ impl Boll {
         }
     }
 
-    pub fn draw(&mut self,canvas: &mut Canvas<Window>, size: u32) {
+    fn draw(&mut self, canvas: &mut Canvas<Window>, size: u32) {
         canvas.set_draw_color(Color::RGBA(
             255 - std::cmp::min(255, (self.vel.length() * 25.0) as u8),
             (255.0 * (self.pos.x / SCREEN_WIDTH as f64)) as u8,