# Main Command: Go
# Polygons (Centre) by Guy Walker
# www.logoarts.co.uk

to new
  # set default screen, pen and turtle
  ResetAll SetScreenSize [400 400] HideTurtle
  SetSC Black SetPC Green SetPS 1 PenUp
end

to go
  New For [N 3 9] [
    Polygon :N 384 Wait 30]
end

to polygon :n :wide
  # polygon of 'N' sides drawn from centre (tp)
  Make "Side :Wide *Sin 180/:N     # length of one side
  Right 180/:N Back :Wide/2 Right 90-180/:N PenDown
  Repeat :N 
    [Forward :Side Left 360/:N]
  PenUp Left 90-180/:N Forward :Wide/2 Left 180/:N     # return to centre
end