void example_lvgl_rounder_cb(struct _lv_disp_drv_t *disp_drv, lv_area_t *area)
{
    uint16_t x1 = area->x1;
    uint16_t x2 = area->x2;

    uint16_t y1 = area->y1;
    uint16_t y2 = area->y2;

    // round the start of coordinate down to the nearest 2M number
    area->x1 = (x1 >> 1) << 1;
    area->y1 = (y1 >> 1) << 1;
    // round the end of coordinate up to the nearest 2N+1 number
    area->x2 = ((x2 >> 1) << 1) + 1;
    area->y2 = ((y2 >> 1) << 1) + 1;
}