How to reference a GEN parameter in JUCE app?

Ok.

Here is the guide for RNBO:

https://github.com/Cycling74/rnbo.example.juce/blob/main/CUSTOM_UI.md

Where the same technic used to inject parameters:

//[MiscUserCode] You can add your own definitions of your custom methods or any other code here...
void RootComponent::setAudioProcessor(RNBO::JuceAudioProcessor *p)
{
    processor = p;

    RNBO::ParameterInfo parameterInfo;
    RNBO::CoreObject& coreObject = processor->getRnboObject();

    for (unsigned long i = 0; i < coreObject.getNumParameters(); i++) {
        auto parameterName = coreObject.getParameterId(i);
        RNBO::ParameterValue value = coreObject.getParameterValue(i);
        Slider *slider = nullptr;
        if (juce::String(parameterName) == juce__slider.get()->getName()) {
            slider = juce__slider.get();
        } else if (juce::String(parameterName) == juce__slider2.get()->getName()) {
            slider = juce__slider2.get();
        } else if (juce::String(parameterName) == juce__slider3.get()->getName()) {
            slider = juce__slider3.get();
        }

        if (slider) {
            slidersByParameterIndex.set(i, slider);
            coreObject.getParameterInfo(i, &parameterInfo);
            slider->setRange(parameterInfo.min, parameterInfo.max);
            slider->setValue(value);
        }
    }
}
//[/MiscUserCode]

As in gen~ example:

void addSliders()
    {
        Component *sliderHolder = m_uiComponent->getSliderHolder();
        
        if (sliderHolder) {
            for (long i = 0; i < C74_GENPLUGIN::num_params(); i++) {
                Slider *slider = new Slider();
                double min = 0;
                double max = 1;
                
                if (C74_GENPLUGIN::getparameterhasminmax(m_C74PluginState, i)) {
                    min = C74_GENPLUGIN::getparametermin(m_C74PluginState, i);
                    max = C74_GENPLUGIN::getparametermax(m_C74PluginState, i);
                }

                slider->setSliderStyle(Slider::SliderStyle::LinearHorizontal);
                slider->setRange(min, max);
                slider->setName(String((int)i));
                slider->addListener(this);
                
                sliderHolder->addAndMakeVisible(slider);
            }
        }
        
        Component *sliderLabelHolder = m_uiComponent->getSliderLabelHolder();
        
        if (sliderLabelHolder) {
            for (long i = 0; i < C74_GENPLUGIN::num_params(); i++) {
                Label *sliderLabel = new Label();
                sliderLabel->setText(String(C74_GENPLUGIN::getparametername(m_C74PluginState, i)), NotificationType::dontSendNotification);
                sliderLabelHolder->addAndMakeVisible(sliderLabel);
            }
        }
        
        resized();
    }

The only difference I see is in implementation, for example there is no Gen~ tutorial and I don't know how to realize this parts of code from RNBO example:

//[UserMethods]     -- You can add your own custom methods in this section.
void setAudioProcessor(RNBO::JuceAudioProcessor *p);
void updateSliderForParam(unsigned long index, double value);
//[/UserMethods]

And:

//[UserVariables]   -- You can add your own custom variables in this section.
RNBO::JuceAudioProcessor *processor = nullptr;
HashMap<int, Slider *> slidersByParameterIndex; // used to map parameter index to slider we want to control
//[/UserVariables]

Besides I need to create GUI reference like the one in RNBO:

void RootComponent::sliderValueChanged (juce::Slider* sliderThatWasMoved)
{
    //[UsersliderValueChanged_Pre]
    if (processor == nullptr) return;
    RNBO::CoreObject& coreObject = processor->getRnboObject();
    auto parameters = processor->getParameters();
    //[/UsersliderValueChanged_Pre]

    if (sliderThatWasMoved == juce__slider.get())
    {
        //[UserSliderCode_juce__slider] -- add your slider handling code here..
        //[/UserSliderCode_juce__slider]
    }
    else if (sliderThatWasMoved == juce__slider2.get())
    {
        //[UserSliderCode_juce__slider2] -- add your slider handling code here..
        //[/UserSliderCode_juce__slider2]
    }
    else if (sliderThatWasMoved == juce__slider3.get())
    {
        //[UserSliderCode_juce__slider3] -- add your slider handling code here..
        //[/UserSliderCode_juce__slider3]
    }

    //[UsersliderValueChanged_Post]
    RNBO::ParameterIndex index = coreObject.getParameterIndexForID(sliderThatWasMoved->getName().toRawUTF8());
    if (index != -1) {
        const auto param = processor->getParameters()[index];
        auto newVal = sliderThatWasMoved->getValue();

        if (param && param->getValue() != newVal)
        {
            param->beginChangeGesture();
            param->setValueNotifyingHost(newVal);
            param->endChangeGesture();
        }
    }
    //[/UsersliderValueChanged_Post]
}

Instead of:

void sliderValueChanged (Slider* slider)
    {
        long index = atoi(slider->getName().getCharPointer());
        C74_GENPLUGIN::setparameter(m_C74PluginState, index, slider->getValue(), NULL);
    }

I don't mind about dynamically updating parameters at this point, I just wonder why there is no such guide for Gen~ part?