Timeline: Clamp event min/max x coord to viewport (#111)

Limit the event canvas-space coordinates to the size of the viewport to
stop labels running off the right-hand side of the screen.

Author: solidpixel

lglpy/timeline/drawable/world_drawable.py

@@ -110,6 +110,10 @@ def draw(self, gc, vp):
         # Round based on final WS position not on WS width
         max_x, max_y = vp.transform_ws_to_cs(self.ws.max_x, self.ws.max_y, 2)
 
+        # Clamp extents to viewport size
+        x = max(x, vp.cs.min_x)
+        max_x = min(max_x, vp.cs.max_x)
+
         # Calculate canvas-space width and height
         w = max_x - x + 1
         h = max_y - y + 1