Function knobValueChanged

dgl/src/ImageBaseWidgets.cpp:309–317

    }

    void knobValueChanged(SubWidget* const widget, const float value) override
    {
        if (rotationAngle == 0 || alwaysRepaint)
            isReady = false;

        if (callback != nullptr)
            if (ImageBaseKnob* const imageKnob = dynamic_cast<ImageBaseKnob*>(widget))
                callback->imageKnobValueChanged(imageKnob, value);
    }

    void knobDoubleClicked(SubWidget* const widget) override
    {