diff --git a/chameleonic.p8 b/chameleonic.p8
index 3d3066c..512d466 100644
--- a/chameleonic.p8
+++ b/chameleonic.p8
@@ -103,13 +103,14 @@ end
 
 
 function _rast(
- x0,y0,x1,y1
+ xs,ys,x0,y0,x1,y1
 )
- local dx=abs(x1-x0)
- local dy=abs(y1-y0)
- local x=x0
- local y=y0
+ local function _add()
+  local n=#xs
+  if (n==0 or xs[n]!=x0 or ys[n]!=y0) add(xs,x0) add(ys,y0)
+ end
 
+ local dx,dy=abs(x1-x0),abs(y1-y0)
  local sx=-1
  local sy=-1
  if (x0<x1) sx=1
@@ -118,27 +119,22 @@ function _rast(
  local done=false,err
  if dx>dy then
   err=dx/2.0
-  return function()
-   if (done) return 
-   if (x==x1) done=true return x1,y1
-   local oldx,oldy=x,y
+  while x0!=x1 do
+   _add()
    err-=dy
-   if (err<0) y+=sy err+=dx
-   x+=sx
-   return oldx,oldy
+   if (err<0) y0+=sy err+=dx
+   x0+=sx
   end
  else
   err=dy/2.0
-  return function()
-   if (done) return
-   if (y==y1) done=true return x1,y1
-   local oldx,oldy=x,y
+  while y0!=y1 do
+   _add()
    err-=dx
-   if (err<0) x+=sx err+=dy 
-   y+=sy
-   return oldx,oldy
+   if (err<0) x0+=sx err+=dy 
+   y0+=sy
   end
  end
+ _add()
 end
 
 -->8
@@ -1199,12 +1195,7 @@ function rope:_check_sane()
   local n1=n0.next
   if (n1==nil) break 
 
-  for qx,qy in _rast(flr(n0.ax*2),flr(n0.ay*2),flr(n1.ax*2),flr(n1.ay*2)) do
-   if not (qx==qxs[#qxs] and qy==qys[#qys]) then
-    add(qxs,qx)
-    add(qys,qy)
-   end
-  end
+  _rast(qxs,qys,flr(n0.ax*2),flr(n0.ay*2),flr(n1.ax*2),flr(n1.ay*2)) 
   n0=n1
  end