working extension system

src/main.rs

@@ -1,11 +1,33 @@
-use osui::{style::Transform, Screen};
+use osui::{
+    extensions::{
+        tick::{OnTick, TickExtension},
+        velocity::{Velocity, VelocityExtension},
+    },
+    style::{Position, Transform},
+    Screen,
+};
 
 fn main() {
     let mut screen = Screen::new();
+    screen.extension(VelocityExtension);
+    screen.extension(TickExtension);
 
     screen
         .draw(format!("Hello, World!"))
-        .component(Transform::center());
+        .component(Transform::new())
+        .component(Velocity(1, 0))
+        .component(OnTick(|w| {
+            if let Some(mut v) = w.get::<Velocity>() {
+                if let Some(t) = w.get::<Transform>() {
+                    if let Position::Const(c) = t.x {
+                        if c == 30 {
+                            v.0 = 0;
+                            w.set_component(v);
+                        }
+                    }
+                }
+            }
+        }));
 
     screen.run().unwrap();
 }