Try to fix snake

buba/__main__.py

@@ -34,7 +34,7 @@ animator.add(DBFAnimation, ds100="AHST", station="Holstenstraße")
 animator.add(DBFAnimation, ds100="AHS", station="Altona", count=9)
 animator.add(IcalEvents, url="https://cloud.hamburg.ccc.de/remote.php/dav/public-calendars/QJAdExziSnNJEz5g?export",
              title="CCCHH Events")
-# animator.add(SnakeAnimation)
+animator.add(SnakeAnimation)
 
 @app.route("/static/<filepath>")
 def server_static(filepath):

buba/animations/snake.py

@@ -13,6 +13,7 @@ class SnakeAnimation(BubaAnimation):
         self.width = 20
         self.height = 4
         self.grid = []
+        self.prev_grid = []
         self.body = []
         # 0:Space
         self.charset = " "
@@ -35,6 +36,7 @@ class SnakeAnimation(BubaAnimation):
 
     def run(self):
         self.grid = [list([0] * self.width) for i in range(self.height)]
+        self.prev_grid = [list([0] * self.width) for i in range(self.height)]
         x = random.randrange(self.width)
         y = random.randrange(self.height)
         d = random.randrange(4)
@@ -97,6 +99,9 @@ class SnakeAnimation(BubaAnimation):
                 self.grid[y][x] != 0)
 
     def render(self):
-        for r, row in enumerate(self.grid):
-            for c, col in enumerate(row):
-                self.buba.text(0, r, c*6, (c+1)*6-1, self.charset[col])
+        for x in range(self.width):
+            for y in range(self.height):
+                if self.grid[y][x] != self.prev_grid[y][x]:
+                    c = x*6
+                    self.buba.text(0, y, c, c+5, self.charset[self.grid[y][x]])
+                    self.prev_grid[y][x] = self.grid[y][x]