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 Gridd : M : N
  # return X Y screen position
  Make " X ( : N * : CellSize ) -180
  Make " Y ( : M * : CellSize ) -180
  Output List : X : Y
End

To DrawGrid
  # draw M x N array of squares
  For (List " M 5 1 Minus 1) [
    For (List " N 5 1 Minus 1) [
      SetPos Gridd ( : M * : M )/5 ( : N * : N )/5 Rect 8* : M 8* : N Left 90
      SetXY Minus 1*First Pos Last Pos Rect 8* : N 8* : M Left 90
      SetXY First Pos Minus 1*Last Pos Rect 8* : M 8* : N Left 90
      SetXY Minus 1*First Pos Last Pos Rect 8* : N 8* : M Left 90 ] ]
End

To Rect : Width : Height
  # shaded rectangle (width x height) drawn from centre (tp) and filled
  Back : Height /2 Right 90 Back : Width /2 PenDown
  SetPC Black Forward : Width Left 90 Forward : Height Left 90
  SetPC White Forward : Width Left 90 Forward : Height Left 90
  PenUp Forward : Width /2 Left 90 Forward : Height /2
  SetPC [153 0 204] Fill
End

To Go
  New SetSC [51 204 102] SetPW 2
  Left 90     # change to 270 to zoom in
  Make " CellSize 30
  DrawGrid
End

To Rect : Width : Height
  # shaded pebble shape drawn from centre (tp) and filled
  LocalMake " Diff Abs : Width - : Height
  If : Width > : Height
    [LocalMake " Rad : Height /2 LocalMake " Vert 0 LocalMake " Horiz : Diff ]
    [LocalMake " Rad : Width /2 LocalMake " Vert : Diff LocalMake " Horiz 0]
  PenUp Back : Height /2 Right 90 Back : Horiz /2 PenDown
  SetPC Black Forward : Horiz LeftArc 90 : Rad Forward : Vert LeftArc 45 : Rad
  SetPC White LeftArc 45 : Rad Forward : Horiz LeftArc 90 : Rad Forward : Vert LeftArc 45 : Rad
  SetPC Black LeftArc 45 : Rad
  PenUp Forward : Horiz /2 Left 90 Forward : Height /2 # return to centre
  SetPC [153 0 204] Fill
End

To LeftArc : Angle : Radius
  # arc drawn relative to turtle position, angle & radius positive
  PenUp Right 90 Back : Radius Left : Angle
  Arc : Radius Heading Heading+ : Angle
  Forward : Radius Left 90 PenDown
End