rect (int_x1, int_y1, int_x2, int_y2, int_colour);
Draw rectangle whose top-left corner is specified with the coordinates (x1,y1) and bottom-right corner at coordinates (x2,y2). If any part of the rectangle falls outside of the screen boundaries, only the visible remainder is drawn.
If the colour is specified as negative number, only the outline of the rectangle will be drawn, otherwise if the colour is a positive number, the rectangle will be solid.
The function has no effect in the console or on text-only displays.