View.Set ("offscreenonly")
View.Set ("graphics:max;max,nobuttonbar")

var strech := 300
var lines := 96

/*
This is some weird effect that I don't know how it works.

-> Strech changes the size of the strech

-> Lines is the number of lines rendered per red/white object, they
evenly go into 6 for a "full figure"

-> I centered the intersection of the two for 100 lines (near this
number anyway).
*/

var midx := round (maxx / 2) - 225
var midy := round (maxy / 2) - 225

Draw.Fill (1, 1, black, black)
colourback (black)
var y := 0

var x1, y1 := 0
var x2, y2 := 0

loop
    for n : 0 .. strech
        View.Update
        cls
        for x : 1 .. lines
            y1 := y2 + 100
            y2 := n * round (cos (x)) + 100
            x1 := x2 + 100
            x2 := x + 100
            Draw.Line (x1 + 50 + midx, y1 + 100 + midy, x2 + 50 + midx, y2 + 100 + midy, white)
            Draw.Line (y1 + 100 + midx, x1 + 50 + midy, y2 + 100 + midx, x2 + 50 + midy, red)
        end for

    end for

    for decreasing n : strech .. 0
        View.Update
        cls
        for x : 1 .. lines
            y1 := y2 + 100
            y2 := n * round (cos (x)) + 100
            x1 := x2 + 100
            x2 := x + 100
            Draw.Line (x1 + 50 + midx, y1 + 100 + midy, x2 + 50 + midx, y2 + 100 + midy, white)
            Draw.Line (y1 + 100 + midx, x1 + 50 + midy, y2 + 100 + midx, x2 + 50 + midy, red)
        end for
    end for
    %delay (50)
end loop