// Dedicated to the public domain by Christopher Diggins
// This file is free to be used, modified or redistributed for any purpose,
// without restriction, obligation, or warantee.
// http://www.cdiggins.com

//=============================================================================

define ow
{ open_window }

define cw
{ close_window }

define sw
{ save_window }

define line_to
{ unit swons 0 cons 0 cons "Line" render }

define move_to
{ unit swons "Slide" render }

define fd
{ dup 0 line_to 0 move_to}

define forward
{ fd }

define bk
{ neg fd }

define back
{ bk }

define turn_right
{ unit "Rotate" render }

define tr
{ turn_right }

define turn_left
{ neg tr }

define tl
{ turn_left }

define set_pen_up
{ unit "SetPenUp" render }

define pu
{ true set_pen_up }

define pd
{ false set_pen_up }

define set_pen_width
{ unit "SetPenWidth" render }

define pw
{ set_pen_width }

define set_turtle_visibility
{ unit "SetTurtleVisibility" render }

define show_turtle
{ true set_turtle_visibility }

define st
{ show_turtle }

define hide_turtle
{ false set_turtle_visibility }

define ht
{ hide_turtle }

define draw_reg_line_seq(len n angle)
{{
  desc:
    Draws a sequence of "n" lines with length "len" and an angle of "angle".
}}
{ [len fd angle tr] n repeat }

define draw_reg_poly(len n)
{{
  desc:
    Draws a regular polygon with each side of length "side" and with "n" sides
}}
{ len n 360 n / draw_reg_line_seq }

define draw_triangle(len)
{ len 3 draw_reg_poly }

define draw_square(len)
{ len 4 draw_reg_poly }

define sq
{ draw_square }

define draw_pentagon(len)
{ len 5 draw_reg_poly }

define draw_hexagon(len)
{ len 6 draw_reg_poly }

define draw_septagon(len)
{ len 7 draw_reg_poly }

define draw_octagon(len)
{ len 8 draw_reg_poly }

define draw_nonagon(len)
{ len 9 draw_reg_poly }

define draw_decagon(len)
{ len 10 draw_reg_poly }

define draw_hendecagon(len)
{ len 11 draw_reg_poly }

define draw_dodecagon(len)
{ len 12 draw_reg_poly }

define draw_polygram(rad n k)
{{
  desc:
    Draws a regular star polygon
}}
{ \i.[rad i k + point_on_circle] n for }

define draw_pentagram(len)
{ len 5 draw_polygram }

define draw_hexagram(len)
{ len 6 draw_polygram }

define rgb
{ triple "Rgb" render }

define red
{ 0xFF 0x00 0x00 rgb }

define green
{ 0x00 0xFF 0x00 rgb }

define blue
{ 0x00 0x00 0xFF rgb }