diff --git a/imgs/circle.png b/imgs/circle.png
new file mode 100644
index 0000000..a0d9618
Binary files /dev/null and b/imgs/circle.png differ
diff --git a/imgs/square.png b/imgs/square.png
new file mode 100644
index 0000000..8eb356f
Binary files /dev/null and b/imgs/square.png differ
diff --git a/output.png b/output.png
index e8381c9..91684fd 100644
Binary files a/output.png and b/output.png differ
diff --git a/src/main.rs b/src/main.rs
index 92edce2..d8f458f 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -1,19 +1,45 @@
 mod turtle;
 
-use turtle::Turtle;
+use turtle::{defaults, Turtle};
 
-fn square(turtle: &mut turtle::Turtle) {
-    turtle.left(90.0);
-    turtle.forward(5);
+#[allow(dead_code)]
+fn square() {
+    let mut turtle = Turtle::new();
+    let default_pos = defaults::position();
+    let steps_count = 20;
+
+    turtle.set_pos((
+        default_pos.0 - (turtle.step_length() * steps_count / 2) as i32, 
+        default_pos.1 + (turtle.step_length() * steps_count / 2) as i32
+    ));
+
+    turtle.left_forward(90.0, steps_count);
     for _ in 0..3 {
-        turtle.right(90.0);
-        turtle.forward(5);
+        turtle.right_forward(90.0, steps_count);
     }
+    turtle.save("imgs/square.png").unwrap();
+}
+
+#[allow(dead_code)]
+fn circle() {
+    let mut turtle = Turtle::new();
+    let default_pos = defaults::position();
+
+    let circumference = (36 * 2 * defaults::STEP_LENGTH) as f64;
+    let radius = circumference / (2.0 * std::f64::consts::PI);
+
+    turtle.set_pos((
+        default_pos.0 - (turtle.step_length() * 2 / 2) as i32,
+        default_pos.1 - radius as i32
+    ));
+    
+    for _ in 0..36 {
+        turtle.forward_right(2, 10.0);
+    }
+    turtle.save("imgs/circle.png").unwrap();
 }
 
 fn main() {
-    let mut turtle = Turtle::new();
-    
-    square(&mut turtle);
-    turtle.save("output.png").unwrap();
+    square();
+    circle();
 }
diff --git a/src/turtle.rs b/src/turtle.rs
index f7edf83..0e05048 100644
--- a/src/turtle.rs
+++ b/src/turtle.rs
@@ -8,36 +8,50 @@ type ImgBufU8 = ImageBuffer<Rgb<u8>, Vec<u8>>;
 type Colour = Rgb<u8>;
 type Coord = (i32, i32);
 
-const DEFAULT_WIDTH: u32 = 300;
-const DEFAULT_HEIGHT: u32 = 300;
-const DEFAULT_BACKGROUND_COLOUR: Colour = Rgb([255u8, 255u8, 255u8]);
-const DEFAULT_COLOUR: Colour = Rgb([0u8, 0u8, 0u8]);
-const DEFAULT_POS: Coord = ((DEFAULT_WIDTH as f64/2.0) as i32, (DEFAULT_HEIGHT as f64/2.0) as i32);
+pub mod defaults {
+    use super::{Colour, Coord, Rgb};
+
+    pub const WIDTH: u32 = 300;
+    pub const HEIGHT: u32 = 300;
+    pub const BACKGROUND_COLOUR: Colour = Rgb([255u8, 255u8, 255u8]);
+    pub const COLOUR: Colour = Rgb([0u8, 0u8, 0u8]);
+    pub const STEP_LENGTH: u32 = 10;
+    pub const ANGLE: f64 = 0.0;
+
+    pub fn position() -> Coord {
+        ((WIDTH as f64 / 2.0) as i32, 
+        (HEIGHT as f64 / 2.0) as i32)
+    }
+}
 
 pub struct Turtle {
     buf: ImgBufU8,
     colour: Colour,
     pos: Coord,
     step_length: u32,
-    angle: f64, // угол в радианах
+    angle: f64,
 }
 
 impl Turtle {
     pub fn new() -> Self {
-        let mut buf = ImageBuffer::new(DEFAULT_WIDTH, DEFAULT_HEIGHT);
+        let mut buf = ImageBuffer::new(defaults::WIDTH, defaults::HEIGHT);
         for pixel in buf.pixels_mut() {
-            *pixel = DEFAULT_BACKGROUND_COLOUR;
+            *pixel = defaults::BACKGROUND_COLOUR;
         }
 
         Turtle {
             buf,
-            colour: DEFAULT_COLOUR,
-            pos: DEFAULT_POS,
-            step_length: 10,
-            angle: 0.0,
+            colour: defaults::COLOUR,
+            pos: defaults::position(),
+            step_length: defaults::STEP_LENGTH,
+            angle: defaults::ANGLE,
         }
     }
 
+    pub fn step_length(&self) -> u32 {
+        self.step_length
+    }
+
     pub fn position(&self) -> Coord {
         self.pos
     }
@@ -46,26 +60,55 @@ impl Turtle {
         self.angle.to_degrees()
     }
 
+    pub fn set_pos(&mut self, coord: Coord) {
+        self.pos.0 = coord.0;
+        self.pos.1 = coord.1;
+    }
+
+    pub fn right(&mut self, degrees: f64) {
+        self.angle += degrees.to_radians();
+        self.angle = self.angle.rem_euclid(2.0 * std::f64::consts::PI);
+    }
+
+    pub fn right_forward(&mut self, degrees: f64, steps_count: u32) {
+        self.right(degrees);
+        self.forward(steps_count);
+    }
+
+    pub fn forward_right(&mut self, steps_count: u32, degrees: f64) {
+        self.forward(steps_count);
+        self.right(degrees);
+    }
+
+    pub fn left(&mut self, degrees: f64) {
+        self.angle -= degrees.to_radians();
+        self.angle = self.angle.rem_euclid(2.0 * std::f64::consts::PI);
+    }
+
+    pub fn left_forward(&mut self, degrees: f64, steps_count: u32) {
+        self.left(degrees);
+        self.forward(steps_count);
+    }
+
+    pub fn forward_left(&mut self, steps_count: u32, degrees: f64) {
+        self.forward(steps_count);
+        self.left(degrees);
+    }
+
     pub fn forward(&mut self, steps_count: u32) {
         let start_pos = self.pos;
 
         let dy = self.angle.sin() * steps_count as f64 * self.step_length as f64;
         let dx = self.angle.cos() * steps_count as f64 * self.step_length as f64;
         
-        self.pos.0 += dx.round() as i32;
-        self.pos.1 += dy.round() as i32;
-        
+        self.set_pos((
+            self.pos.0 + dx.round() as i32,
+            self.pos.1 + dy.round() as i32
+        ));
+
         self.draw_line(start_pos, self.pos);
     }
 
-    pub fn right(&mut self, degrees: f64) {
-        self.angle += degrees.to_radians();
-    }
-
-    pub fn left(&mut self, degrees: f64) {
-        self.angle -= degrees.to_radians();
-    }
-
     pub fn save<P>(&self, output_path: P) -> ImageResult<()> 
     where
         P: AsRef<Path>