first commit

src/main.rs

@@ -0,0 +1,92 @@
+extern crate image;
+extern crate num_complex;
+
+use image::{RgbImage, ImageBuffer, Rgb};
+use std::fmt::Error;
+use num_complex::Complex;
+use uuid::Uuid;
+use std::ops::Add;
+
+const THRESHHOLD: f64 = 200.0;
+
+fn calculate_color(number: Complex<f64>, iterations: u32) -> Result<Rgb<u8>, Error> {
+    let mut z: Complex<f64> = Complex::new(0.0, 0.0);
+    let mut cycle = Vec::with_capacity(iterations as usize);
+
+    for i in 0..iterations {
+        z = z * z + number;
+
+        if cycle.contains(&z) { return Ok(Rgb::from([0, 0, 0])); }
+
+        if z.norm() > THRESHHOLD {
+            return Ok(map_num_to_color(i, iterations));
+        }
+
+        cycle.push(z);
+    }
+    Ok(map_num_to_color(iterations, iterations))
+}
+
+fn map_num_to_color(i: u32, maximum: u32) -> Rgb<u8> {
+    if i == maximum { return Rgb::from([0, 0, 0]); }
+    let frac: f32 = (i as f32 / maximum as f32) * 255.0 * 3.0;
+
+    let r: u8;
+    if frac / 3.0 >= 255.0 {
+        r = 255
+    } else { r = (frac as i32 % 255) as u8 }
+
+    let g: u8;
+    if frac / 3.0 >= 255.0 * 2.0 {
+        g = 255
+    } else { g = (frac as i32 % 255) as u8 }
+
+    let b: u8;
+    if frac / 3.0 >= 255.0 * 3.0 {
+        b = 255
+    } else { b = (frac as i32 % 255) as u8 }
+
+    Rgb::from([r, g, b])
+}
+
+fn generate_mandelbrot(width: u32,
+                       height: u32,
+                       iterations: u32,
+                       upper_left: Complex<f64>,
+                       lower_right: Complex<f64>) -> Result<RgbImage, Error> {
+    let mut out_image: RgbImage = ImageBuffer::new(width, height);
+
+    let section_width: f64 = (upper_left.re - lower_right.re).abs();
+    let section_height: f64 = (upper_left.im - lower_right.im).abs();
+
+    for x in 0..width {
+        println!("Col: {}", x);
+        for y in 0..height {
+            let x_offset: f64 = (x as f64 / width as f64) * section_width;
+            let y_offset: f64 = (y as f64 / width as f64) * section_height;
+
+            let color = calculate_color(
+                Complex::new(upper_left.re + x_offset, upper_left.im + y_offset),
+                iterations).unwrap();
+
+            out_image.put_pixel(x, y, color);
+        }
+    }
+
+    Ok(out_image)
+}
+
+
+fn main() {
+    let fractal: RgbImage = generate_mandelbrot(4096,
+                                                4096,
+                                                100,
+                                                Complex::new(-0.7, -0.7),
+                                                Complex::new(-0.4, -0.4))
+        .unwrap();
+
+    let filename: String = String::from("mandelbrot_")
+        .add(&Uuid::new_v4().to_string()) + ".png";
+
+    fractal.save(filename).unwrap();
+}