--- a/mamba/sprites.py	Fri Sep 16 23:42:00 2011 +0200
+++ b/mamba/sprites.py	Fri Sep 16 23:43:33 2011 +0200
@@ -243,6 +243,43 @@
             head.shift_tile_and_pixels((other.tile_pos, self.direction))
 
 
+class ButtonSprite(SingleImageTileSprite):
+    image_name = 'button'
+    name = 'button'
+    tileset = 'lab'
+
+    def __init__(self, other_id):
+        super(ButtonSprite, self).__init__(tile_char=None)
+        self.other_id = other_id
+
+    def interact(self, world, segment):
+        head = world.snake.head
+        if segment is head:
+            other = world.get_sprite(self.other_id)
+            other.button_pushed()
+
+
+class GateSprite(SingleImageTileSprite):
+    closed_name = 'closed_gate'
+    open_image = 'open_gate'
+    name = 'gate'
+    tileset = 'lab'
+
+    def __init__(self):
+        self.image_name = self.closed_name
+        self.opened = False
+        super(GateSprite, self).__init__(tile_char=None)
+
+    def get_solid(self, snake, segment):
+        return not self.opened
+
+    def button_pushed(self):
+        self.opened = True
+        # Update image
+        self.image_name = self.open_image
+        self.image = self.load_image(self.image_name, mutators=())
+
+
 class PuddleSprite(SingleImageTileSprite):
     image_name = 'puddle'
     name = 'puddle'