June 2018 Update

Task/Fractal-tree/Rust/fractal-tree.rust

@@ -0,0 +1,57 @@
+//Cargo deps :
+//  piston = "0.35.0"
+//  piston2d-graphics = "0.23.0"
+//  piston2d-opengl_graphics = "0.49.0"
+//  pistoncore-glutin_window = "0.42.0"
+
+extern crate piston;
+extern crate graphics;
+extern crate opengl_graphics;
+extern crate glutin_window;
+
+use piston::window::WindowSettings;
+use piston::event_loop::{Events, EventSettings};
+use piston::input::RenderEvent;
+use glutin_window::GlutinWindow as Window;
+use opengl_graphics::{GlGraphics, OpenGL};
+use graphics::{clear, line, Context};
+
+const ANG: f64 = 20.0;
+const COLOR: [f32; 4] = [1.0, 0.0, 0.5, 1.0];
+const LINE_THICKNESS: f64 = 5.0;
+const DEPTH: u32 = 11;
+
+fn main() {
+    let mut window: Window = WindowSettings::new("Fractal Tree", [1024, 768])
+        .opengl(OpenGL::V3_2)
+        .exit_on_esc(true)
+        .build()
+        .unwrap();
+    let mut gl = GlGraphics::new(OpenGL::V3_2);
+
+    let mut events = Events::new(EventSettings::new());
+    while let Some(e) = events.next(&mut window) {
+        if let Some(args) = e.render_args() {
+            gl.draw(args.viewport(), |c, g| {
+                clear([1.0, 1.0, 1.0, 1.0], g);
+                draw_fractal_tree(512.0, 700.0, 0.0, DEPTH, c, g);
+            });
+        }
+    }
+}
+
+fn draw_fractal_tree(x1: f64, y1: f64, angle: f64, depth: u32, c: Context, g: &mut GlGraphics) {
+    let x2 = x1 + angle.to_radians().sin() * depth as f64 * 10.0;
+    let y2 = y1 - angle.to_radians().cos() * depth as f64 * 10.0;
+    line(
+        COLOR,
+        LINE_THICKNESS * depth as f64 * 0.2,
+        [x1, y1, x2, y2],
+        c.transform,
+        g,
+    );
+    if depth > 0 {
+        draw_fractal_tree(x2, y2, angle - ANG, depth - 1, c, g);
+        draw_fractal_tree(x2, y2, angle + ANG, depth - 1, c, g);
+    }
+}