#define IMAGE_HEIGHT (PAD + PAD * ARRAY_LENGTH (int_offset) + PAD * ARRAY_LENGTH (frac_offset) * ARRAY_LENGTH (int_offset))
cairo_move_to (cr, (STROKE_LENGTH + PAD) * k + PAD, PAD * (i + j + ARRAY_LENGTH (frac_offset) * j + 1));
cairo_line_to (cr, (STROKE_LENGTH + PAD) * (k + 1), PAD * (i + j + ARRAY_LENGTH (frac_offset) * j + 1));