Logo Arts

To New
  # set default screen, pen and turtle values
  ResetAll SetScreenSize [400 400] HideTurtle
  SetSC Black SetPC Green SetPS 1 PenUp
End

To Ring : Angle : Dist : Head : Size
  # draw concentric rings of clam shapes
  Home SetH : Angle SetPW : Size /10
  Forward : Dist SetH : Head Clam : Size
  SetPC : FillCol Fill
End

To Clam : Size
  # optical clam shape drawn from centre (tp)
  SetPC White Back : Size /3 Arch 112 0.6* : Size
  Forward : Size /3 Left 180
  SetPC Black Back : Size /3 Arch 112 0.6* : Size
  Forward : Size /3 Left 180
End

To Arch : Angle : Radius
  # symmetrical arc drawn relative to turtle heading
  Arc : Radius Heading- : Angle /2 Heading+ : Angle /2
End

To Go
  New SetPW 3
  SetSC Pick [ [102 204 51] [51 204 102] [204 204 0] ]
  Make " FillCol Pick [ [153 102 0] [128 0 255] [0 128 255] ]
  For [ Angle 0 360 10] [
    Ring : Angle 180 90 30
    Ring : Angle 150 35 25
    Ring : Angle 122 325 20
    Ring : Angle 100 270 15]
End