This function Draw a Grid of With x Height with a made of Element_With x Element_Height rectangles. It can be specified if you want to draw a filled grid, or if you only want to draw the flled part of the grid.
This is a variant of the Bresenham's line algorithm, the circle one. Given the center of the circle (CENTER_x, CENTER_y) with the radious RADIOUS_r it can draw a circle in the LCD. It can be specified if its gone a be a filled Circle or only the circumference of the circle.
This is another variant of the Bresenham's line algorithm (by Jerry Van Aken), the ellipse one. Given the center of the circle (CENTER_x, CENTER_y) with the major axus RADIOUS_a and minor axis RADIOUS_b it can draw an ellipse. Same as before it can be specified the if it would be a fill present or not.