Widget_t * add_image_knob(Widget_t *parent, const char *label, int x, int y, int width, int height)
add_image_knob - add a knob from image to a Widget_t without value display on the knob connect to fun...
Widget_t * add_knob(Widget_t *parent, const char *label, int x, int y, int width, int height)
add_knob - add a knob to a Widget_t connect to func.value_changed_callback to implement your actions ...