add internal state field

src/circle.rs

@@ -1,11 +1,21 @@
-use crate::shapes::Shape;
+use crate::shapes::*;
 
 /// An iterator containing the shapes to display
-pub struct CircleShapes;
+pub struct CircleShapes {
+    modulo: u32,
+    factor: u32,
+    position: u32,
+    circle: Circle,
+}
 
 impl CircleShapes {
-    pub fn new() -> CircleShapes {
+    pub fn new(modulo: u32, factor: u32, circle: Circle) -> CircleShapes {
-        CircleShapes {}
+        CircleShapes {
+            modulo,
+            factor,
+            position: 0,
+            circle,
+        }
     }
 }
 
@@ -13,6 +23,11 @@ impl Iterator for CircleShapes {
     type Item = Shape;
 
     fn next(&mut self) -> Option<Self::Item> {
-        None
+        if self.position == 0 {
+            self.position += 1;
+            Some(Shape::Circle(self.circle))
+        } else {
+            None
+        }
     }
 }

src/lib.rs

@@ -26,17 +26,19 @@ pub fn start() {
 
     context.begin_path();
   
-    let iter = CircleShapes::new();
+    let iter = CircleShapes::new(10, 2, Circle {center: Point {x: 75.0, y: 75.0}, radius: 70.0});
     for shape in iter {
         drawing::draw_shape(shape, &context);
     }
-  
+
+/*
     drawing::draw_circle(Circle {center: Point {x: 75.0, y: 75.0}, radius: 70.0}, &context);
     drawing::draw_circle(Circle {center: Point {x: 75.0, y: 75.0}, radius: 35.0}, &context);
     drawing::draw_circle(Circle {center: Point {x: 60.0, y: 65.0}, radius: 5.0}, &context);
   
     drawing::draw_line(Line {p1: Point {x: 0.0, y: 0.0}, p2: Point {x: 150.0, y: 150.0}}, &context);
     drawing::draw_line(Line {p1: Point {x: 0.0, y: 150.0}, p2: Point {x: 150.0, y: 0.0}}, &context);
-  
+*/
+
     context.stroke();
 }

src/shapes.rs

@@ -1,13 +1,16 @@
+#[derive(Copy, Clone)]
 pub struct Point {
   pub x: f64,
   pub y: f64,
 }
 
+#[derive(Copy, Clone)]
 pub struct Circle {
   pub center: Point,
   pub radius: f64,
 }
 
+#[derive(Copy, Clone)]
 pub struct Line {
   pub p1: Point,
   pub p2: Point,