diff --git a/src/main.rs b/src/main.rs
index 1461117..641e822 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -12,6 +12,7 @@ fn window_conf() -> Conf {
 }
 
 static ANT_SPEED: f32 = 20.;
+static FLOOR_COLOR: Color = Color::new(0.46666667, 0.38431373, 0.3019608, 1.);
 
 struct Ant {
     pos: Vec2,
@@ -19,9 +20,13 @@ struct Ant {
 }
 
 impl Ant {
-    fn walk(&mut self) {
+    fn walk(&mut self, map_data: &Image) {
         let acceleration = Vec2::new(self.dir.sin(), -self.dir.cos());
-        self.pos += acceleration * ANT_SPEED * get_frame_time();
+        let new_pos = self.pos + acceleration * ANT_SPEED * get_frame_time();
+        let dest_pixel = map_data.get_pixel(new_pos.x as u32, new_pos.y as u32);
+        if dest_pixel == FLOOR_COLOR {
+            self.pos = new_pos;
+        }
     }
     fn draw(&self) {
         draw_circle(self.pos.x, self.pos.y, 1., WHITE);
@@ -42,10 +47,11 @@ fn init_ants(num_ants: i32) -> Vec<Ant> {
 #[macroquad::main(window_conf)]
 async fn main() {
     let map = load_texture("map_scaled.png").await.unwrap();
+    let map_data = map.get_texture_data();
     let mut ants = init_ants(16);
     loop {
         // actions
-        ants.iter_mut().for_each(|ant| ant.walk());
+        ants.iter_mut().for_each(|ant| ant.walk(&map_data));
         if is_key_down(KeyCode::Escape) || is_quit_requested() {
             return;
         }