Adding a koch curve example

examples/koch.rs

@@ -0,0 +1,54 @@
+use bevy::prelude::*;
+use bevy_inspector_egui::Inspectable;
+use turtle_lib::builders::Turnable;
+use turtle_lib::turtle_bundle::AnimatedTurtle;
+use turtle_lib::{get_a_turtle, TurtlePlugin};
+
+use bevy::diagnostic::{FrameTimeDiagnosticsPlugin, LogDiagnosticsPlugin};
+
+#[derive(Component, Inspectable)]
+struct Egon {}
+
+fn main() {
+    App::new()
+        .add_plugin(TurtlePlugin)
+        .add_startup_system(setup)
+        //.add_system(plan)
+        .add_plugin(LogDiagnosticsPlugin::default())
+        .add_plugin(FrameTimeDiagnosticsPlugin::default())
+        .run();
+}
+
+fn setup(mut commands: Commands) {
+    let mut turtle = get_a_turtle();
+    turtle.set_speed(1);
+    for x in 0..3 {
+        koch(6, &mut turtle);
+        let mut left = turtle.create_plan();
+        left.left(120.into());
+        turtle.extend_plan(left);
+    }
+    commands.spawn((turtle, Egon {}));
+}
+
+fn koch(depth: u32, turtle: &mut AnimatedTurtle) {
+    if depth == 0 {
+        let mut forward = turtle.create_plan();
+        forward.forward(1.into());
+        turtle.extend_plan(forward)
+    } else {
+        koch(depth - 1, turtle);
+        let mut left = turtle.create_plan();
+        left.left(60.into());
+        turtle.extend_plan(left);
+        koch(depth - 1, turtle);
+        let mut right = turtle.create_plan();
+        right.right(120.into());
+        turtle.extend_plan(right);
+        koch(depth - 1, turtle);
+        let mut left = turtle.create_plan();
+        left.left(60.into());
+        turtle.extend_plan(left);
+        koch(depth - 1, turtle);
+    }
+}