diff --git a/python/shapepath.py b/python/shapepath.py
index 73debc1..18928eb 100755
--- a/python/shapepath.py
+++ b/python/shapepath.py
@@ -1031,6 +1031,93 @@ enable plc 2
           vsy=py/(pt2pt_time)*scale*CoordFeedTime  # scaling for Deltatau
           #variables
           r,x0,y0,n,dx,dy,x1,y1,t,vx,vy=map(lambda x: f'L{x}',range(11))
+
+
+# replace: [^{](x|y|x0|y0|cx|cy|x0|y0|n|dx|dy|vsx|vsy|vx|vy) -> {\1}
+          prg+=f'''\
+  g=kwargs['grid']
+  ox,oy=g['pos']      #origin position in um (or counts if scaled)
+  px,py=g['pitch']    #pitch to next position in um (or 1 if scaled)
+  nx,ny=g['count']    #total count of wells
+  sx,sy=kwargs['ssz'] #section size (in wells)
+  tx,ty=nx//sx,ny//sy #total sections
+
+  k=-1            # key position
+  cx,cy=0,0       # section counter
+  x0,y0,n=0,0,0   # counter well in region
+  dx,dy=0,1       # motion pitch
+  vsx=vsy=1       # scaled velocity
+  vx,vy=0,vsy     # scaled velocity
+  mv=list()
+  while(True):
+    if cy%2==0: # even rows
+      x=sx*cx+x0;y=sy*cy+y0
+    else:       # odd rows
+      x=(tx-cx)*sx-x0-1;y=sy*cy+y0
+      vx=-vx
+    x0+=dx;y0+=dy
+    print(f'X{x}:{vx} Y{y}:{vy} ({k}|{dx}|{dy}|{n})')
+    mv.append((x+.1*n,y+.1*n,n))
+    self.updatePlt(mv,vx,vy)
+    if k>=0: #if keypoint not directly followed by an other keypoint, define future velocity
+      if k in (0,4):
+        vx,vy=0,vsy
+      elif k==2:
+        vx,vy=0,-vsy
+      elif k==5:
+        vx,vy=-vsx,0
+      elif k==6:
+        n+=1
+      elif k==7:
+        print('next h section')
+        cx+=1
+        x0,y0,n,dx,dy=0,0,0,0,0
+      elif k==8:
+        print('next v section')
+        cx=0;cy+=1
+        x0,y0,n,dx,dy=0,0,0,0,0
+        if cy>=ty:
+          print('finished whole grid')
+          break #
+      else:
+        raise ValueError('should never happened')
+      print(f'vx|vy after keypoint {k}: ({vx}|{vy})')
+      k=-1
+    if y0==sy-1:
+      if dy==1:   #(1)
+        dx,dy=1,0
+        vx,vy=vsx/2,vsy/2
+      else:
+        k,dx,dy=2,0,-1#(2)
+        vx,vy=vsx/2,-vsy/2
+    elif y0==1 and x0>0 and x0<sx-1:
+      if dy==-1:  #(3)
+        dx,dy=1,0
+        vx,vy=vsx/2,-vsy/2
+      else:
+        k,dx,dy=4,0,1 #(4)
+        vx,vy=vsx/2,vsy/2
+    elif y0==0:
+      if n==1 and x0==1: #(7 or 8)
+        if cx<tx-1:
+          k,dx,dy=7,-1,0
+          vx,vy=0,0
+        else: #(8)
+          k,dx,dy=8,sx-1,sy
+          vx,vy=0,0
+      elif x0==1: #(6)
+        k,dx,dy=6,-1,0
+        vx,vy=-vsx,0
+      elif x0==0: #(0)
+        k,dx,dy=0,0,1
+        vx,vy=0,vsy
+      elif x0==sx-1: #(5)
+        k,dx,dy=5,-1,0
+        vx,vy=-vsx/2,-vsy/2
+
+'''
+
+
           prg+=f'''\
   //mode 6: hit-and-return pvt motion
   {r}=0                // row