traylayout: set size of canvas

boxes/generators/traylayout.py

@@ -91,18 +91,26 @@ class Layout(Boxes):
         edge(length)
 
     def render(self):
-        self.open(1000, 600)
 
         self.hi = hi = self.hi or self.h
-        
-        self.edges["s"] = boxes.edges.Slot(self, self.hi/2.0)
-        self.edges["C"] = boxes.edges.CrossingFingerHoleEdge(self, self.hi)
 
         lx = len(self.x)
         ly = len(self.y)
         t = self.thickness
         t2 = self.thickness / 2.0
-        
+
+        hasfloor = False
+
+        for line in self.floors:
+            for f in line:
+                hasfloor |= f
+
+        self.open(max((lx+1)*sum(self.y), (ly+1)*sum(self.x))+lx*ly*4*t,
+                  2*self.h + hasfloor*sum(self.y) + 12*t)
+
+        self.edges["s"] = boxes.edges.Slot(self, self.hi/2.0)
+        self.edges["C"] = boxes.edges.CrossingFingerHoleEdge(self, self.hi)
+
         self.ctx.save()
 
         # Horizontal Walls