GUI Params not affecting filter values

Hi, I’m just starting out learning C++ and the JUCE framework. I’m working off of this tutorial for making a first filter plugin to get myself into it (timecode included as for how far along in the tut I am.) I’m able to build this plugin with a peak filter, I’m not getting any errors and no crashes when building or running, but changing the gui values assigned for the filter does nothing. I figure I’m not hooking up a value somewhere or something’s being set initially but not getting updated, I don’t know how to determine that. I’ve gotten to the point in the tutorial where I should be testing the filter, audio is piping through the plugin fine but with no change. As far as I can tell this is the relevant order of operations:

  • struct w/ members created
  • value tree state created
  • function to update struct members using raw values taken from value tree state, called every process block
  • peak filter coefficients created and set using updated values from struct members
  • chain processed using peak filter coefficients

I’m just starting out, so assume I know nothing and ask anything if I’ve missed something out.


At this point with that information it is impossible to say.
But looking at your list, did you connect the GUI to the state using SliderParameterAttachment?

I’m using getRawParameterValue

That is from state to DSP, but from slider to state might be missing…

N.B. I am not a fan of getRawParameterValue. It’s much better to use the AudioParameterFloat* as member and call ->get()

I’m going through the tutorial, I don’t really have a handle on what I’m doing yet.