View.Set ("graphics:800,600,nobuttonbar")
function mid (n, n2 : real) : int
    result round ((n2 + n) / 2)
end mid
function distance (x1, y1, x2, y2 : real) : real
    result ((x1 - x2) ** 2 + (y1 - y2) ** 2) ** 0.5
end distance
var count : int := 1
proc drawTri (x1, y1, x2, y2, x3, y3 : real)
    var xd, yd, mx, my : array 1 .. 3 of int
    var size : real
    mx (1) := mid (x2, x1)
    mx (2) := mid (x2, x3)
    mx (3) := mid (x1, x3)
    my (1) := mid (y1, y2)
    my (2) := mid (y2, y3)
    my (3) := mid (y1, y3)
    xd (1) := round(x1)
    xd (2) := round(x2)
    xd (3) := round(x3)
    yd (1) := round(y1)
    yd (2) := round(y2)
    yd (3) := round(y3)
    size := distance (mx (1), my (1), mx (2), my (2))
    if size <= 2 then
        return
    end if
    drawfillpolygon (xd, yd, 3, gray)
    drawfillpolygon (mx, my, 3, black)
    drawTri (mx (1), my (1), mx (2), my (2), x2, y2)
    drawTri (mx (3), my (3), mx (2), my (2), x3, y3)
    drawTri (mx (1), my (1), mx (3), my (3), x1, y1)
end drawTri
drawfillbox (0, 0, maxx, maxy, 7)
drawTri (50, 50, maxx div 2, maxy - 50, maxx - 50, 50)