dbngraphics.dbn

// dbngraphics
command triangle h1 v1 h2 v2 h3 v3
{
  line h1 v1 h2 v2
  line h2 v2 h3 v3
  line h3 v3 h1 v1
}
command rectangle left bot right top
{
  line left bot right bot
  line right bot right top
  line right top left top
  line left top left bot
}

command circlepixels cx cy dx dy v
{
  set [(cx+dx) (cy+dy)] v
  set [(cx+dx) (cy-dy)] v
  set [(cx-dx) (cy+dy)] v
  set [(cx-dx) (cy-dy)] v
  set [(cx+dy) (cy+dx)] v
  set [(cx+dy) (cy-dx)] v
  set [(cx-dy) (cy+dx)] v
  set [(cx-dy) (cy-dx)] v
}

command circle cx cy radius v
{
  set x 0
  set y radius
  set d (1-radius)
  circlepixels cx cy x y v
  // 707/1000 approximates square root of 0.5 = cos(45)
  repeat x 0 (radius*707/1000)
  {
    set tempd d
    smaller? tempd 0
    {
      set d (d+(2*x)+3)
    }
    notsmaller? tempd 0
    {
      set d (d+(2*(x-y))+5)
      set y (y-1)
    }
    circlepixels cx cy x y v
  }
}
command testdbngraphics
{
field 2 2 98 98 15
pen 100
triangle 50 96 50 4 96 50
circle 50 50 46 100
rectangle 14 23 68 77
}