made lv_slider_draw_knob params const
static lv_design_res_t lv_slider_design(lv_obj_t * slider, const lv_area_t * clip_area, lv_design_mode_t mode);
static lv_res_t lv_slider_signal(lv_obj_t * slider, lv_signal_t sign, void * param);
static void lv_slider_position_knob(lv_obj_t * slider, lv_area_t * knob_area, lv_coord_t knob_size, bool hor);
-static void lv_slider_draw_knob(lv_obj_t * slider, lv_area_t * knob_area, lv_area_t * clip_area);
+static void lv_slider_draw_knob(lv_obj_t * slider, const lv_area_t * knob_area, const lv_area_t * clip_area);
/**********************
* STATIC VARIABLES
@@ -491,7 +491,7 @@ static void lv_slider_position_knob(lv_obj_t * slider, lv_area_t * knob_area, lv
knob_area->y2 += style_knob->body.padding.bottom;
}
-static void lv_slider_draw_knob(lv_obj_t * slider, lv_area_t * knob_area, lv_area_t * clip_area) {
+static void lv_slider_draw_knob(lv_obj_t * slider, const lv_area_t * knob_area, const lv_area_t * clip_area) {
lv_slider_ext_t * ext = lv_obj_get_ext_attr(slider);
const lv_style_t * style_knob = lv_slider_get_style(slider, LV_SLIDER_STYLE_KNOB);
lv_opa_t opa_scale = lv_obj_get_opa_scale(slider);
