looking at the demo project “Juce_Vst” I see that changing any plugin parameter using DemoJuceFilter::setParameter(…) will call the function DemoJuceFilter::sendChangeMessage(this) which ultimately leads to a call of DemoEditorComponent::updateParametersFromFilter() - a function that just redraws EVERYTHING in the editor´s window.
I saw that this way of doing it was also used in a Juce-based audio plugin called Peggy2000 - just redrawing all 30 sliders on screen when only one slider would be needed to be repainted after a parameter change. This is the most horrible waste of CPU time I´ve ever seen anywhere. Sorry to say it like this, but it´s true.
Now could anyone propose a good/elegant way for only redrawing (asynchronously) the Component (for instance a slider) that is meant to be redrawn for a given parameter upon call of setParameter?
I suppose, calling mySlider->setValue(newValue,false) is not a good practice because it has not been done like that in the demo (perhaps Slider::setValue redraws the slider synchronously???).
I am thankful for all suggestions!