diff --git a/Cargo.toml b/Cargo.toml
index 6d37a80..c26932a 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -9,3 +9,4 @@ edition = "2021"
 image = "0.24.7"
 rand = "0.8.5"
 num_cpus = "1.16.0"
+clap = { version = "4.4.8", features = ["derive"]}
diff --git a/grid_image.png b/grid_image.png
index f3866bf..79f4b39 100644
Binary files a/grid_image.png and b/grid_image.png differ
diff --git a/src/main.rs b/src/main.rs
index 33d5f4c..b6ea47d 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -1,18 +1,27 @@
 #![allow(dead_code)]
 
-use std::env;
+use clap::Parser;
 use rand::Rng;
 use image::Rgb;
 use image::RgbImage;
 use image::ImageBuffer;
 
 
-fn main() {
-    let args: Vec<String> = env::args().collect();
+#[derive(Parser)]
+struct Args {
+    /// Optimization level
+    #[arg(short, default_value_t = 3)]
+    opt_level: u8,
 
-    let _num_chunks = args.get(1)
-        .and_then(|arg: &String| arg.parse::<usize>().ok())
-        .unwrap_or(num_cpus::get());
+    /// Number of cores [default: max]
+    #[arg(short, value_name = "CORES")]
+    core: Option<u8>
+}
+
+
+fn main() {
+
+    let args = Args::parse();
 
     let width = 7000;
     let height = 7000;
@@ -24,10 +33,14 @@ fn main() {
     //     points.push(i as f64 / 10000.0);
     //     // points.push(-(i as f64 / 10000.0));
     // }
-
-    let step = 0.001; // Define the step size
+    
+    let mut step = "0.".to_string();
+    for _ in 0..args.opt_level {
+        step.push('0')
+    }
+    step.push('1');
+    let step: f64 = step.parse().unwrap();
     let mut current_value = 0.0;
-
     while current_value <= 1.8 {
         points.push(current_value);
         current_value += step;
@@ -43,16 +56,17 @@ fn main() {
     ];
     colors.push(color);
     for point in points {
-        let x = (point * 1000.0_f64).round() as u32;
-        let y = (get_point(point) * 1000.0).round() as u32;
+        // NOTE: convert later to u32 because deviding may change actual value
+        let x = point * 1000.0_f64;
+        let y = get_point(point) * 1000.0;
         img.put_pixel(
-            x + width / 2,
-            y + height / 2,
+            (width as f64 / 2.0 + x).round() as u32,
+            (height as f64 / 2.0 + y) as u32,
             Rgb(color)
         );
         img.put_pixel(
-            x + width / 2 - x * 2,
-            y + height / 2,
+            (width as f64 / 2.0 - x).round() as u32,
+            (height as f64 / 2.0 + y).round() as u32,
             Rgb(color)
         );
 
@@ -81,7 +95,7 @@ fn generate_random(start: u8, end: u8) -> u8 {
 
 fn get_image(width: u32, height: u32) -> ImageBuffer<Rgb<u8>, Vec<u8>> {
     let mut img = RgbImage::new(width, height);
-    let grid_spacing = 50;
+    let grid_spacing = 100;
     let grid_color = Rgb([255,9,255]);
 
     for x in (0..width).step_by(grid_spacing) {