// background color
set_default_background_color('black')
// default drawing color
set_default_color('lime')
// default drawing line thickness, in pixels
set_default_line_thickness(3)
// diagonal lines
// from (x0, y0) to (x1, y1)
line(0,0, width,height)
line(width,0, 0,height)
// vertical and horizontal lines
line(0,height/2, width,height/2)
line(width/2,0, width/2,height)
// the radius of the disk is 1/4 of the smallest dimension
// x, y, radius, color
r = min(width, height)/4
disk(width/2, height/2, r, 'red')
// print some stuff
print(" Resize the window to see what happens!", 'cyan')