WDL GUI parameters : MIDI automation

[xhunaudio]

Hello, I'm a newbe using WDL-OL.

I'm getting crazy because I would like to "link" a MIDI message to a GUI Parameter, but I can't figure out how to do it.

I think the method SetDirty() is somewhere involved, but I do not understand where exactly...

I have a GUI parameter in the constructor :

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IControl_knobMainVolume = new IKnobMultiControl(this, kMainVolumeX, kMainVolumeY, kMainVolume, &knob_0001);

pGraphics->AttachControl(IControl_knobMainVolume);

AttachGraphics(pGraphics);

//the knob appear and works correctly

Then in "ProcessDoubleReplacing" :

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//... if a midi "control change 7" message occurs -> :

GetParam(kMainVolume)->Set(pMsg->mData2); //this work fine, the parameter is linked to CC#7

If I "manually" turn the knob from the GUI, the volume changes properly.
If I send a MIDI cc#7 message, the volume changes properly.

But, when I send a MIDI cc#7 message (also if the volume changes properly), the knob image remains unchanged (mid position), it doesn't follow the value set with MIDI slider.

I know I have to do something with SetDirty() , Draw() , and or other methods, do anyone knows how to do it? Or if there's some resource on the internet that explains this thing...

Thank you in advance,

[hibrasil]

you'd be better off asking on the WDL forum

[Mayae]

Even if you do get this working, you don't really want to interact directly with GUI code inside the audio thread (due to locks, memory allocations, non-deterministic stuff that may lock up the real-time thread).

Instead, either flag controls that need redrawing, and then regularly check from the message thread if anything has to be updated. Can also be done using a sort of message lock-free fifo.

[xhunaudio]

you'd be better off asking on the WDL forum

okay.

Waiting for WDL forum access confirmation...

[xhunaudio]

Even if you do get this working, you don't really want to interact directly with GUI code inside the audio thread (due to locks, memory allocations, non-deterministic stuff that may lock up the real-time thread).

Instead, either flag controls that need redrawing, and then regularly check from the message thread if anything has to be updated. Can also be done using a sort of message lock-free fifo.

Hi Mayae, you're right... In WDL, GUI side should be (*maybe*) accessed using GetGUI()->..., so your suggestion is to make something similar to this :

Inside "ProcessMidiMsg" method :

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IControl_knobMainVolume->SetDirty();

or...

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GetGUI()->SetParameterFromPlug();//...

[xhunaudio]

Ok, I got it.

For people that may ask about this in the future, the answer is simply :

GetGUI()->SetControlFromPlug(ParamIdx, Value);

Since this is executed in the "ProcessDoubleReplacing" each time a midi message (cc#7) is picked from the midi queue, so it is executed in the DSP thread, right? Is there any way to make it be executed in the GUI thread to safe CPU?

*maybe* using : if(GetGUI())

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 if(GetGUI()) GetGUI()->SetControlFromPlug(ParamIdx, Value);//?????

I tried to accede to Cockos forum but the confirmation email never arrived.
Someone here knows about the if(GetGUI()) addition?

[hibrasil]

don't have time to really explain it, but here is how you can update a parameter and linked control in response to a MIDI CC, handled in OnMIDIMsg() or when unpacked from the queue in ProcessDoubleReplacing()

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                  double val = pMsg->ControlChange(pMsg->ControlChangeIdx());
                  GetParam(paramIdx)->SetNormalized(val);
                  GetGUI()->SetParameterFromPlug(paramIdx, val, true);
                  OnParamChange(paramIdx);

[xhunaudio]

don't have time to really explain it, but here is how you can update a parameter and linked control in response to a MIDI CC, handled in OnMIDIMsg() or when unpacked from the queue in ProcessDoubleReplacing()

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                  double val = pMsg->ControlChange(pMsg->ControlChangeIdx());
                  GetParam(paramIdx)->SetNormalized(val);
                  GetGUI()->SetParameterFromPlug(paramIdx, val, true);
                  OnParamChange(paramIdx);

Thank you so much for your help! When you'll find some spare time, can you tell me the difference (no docs came with WDL, neither //comments)?

Before your help, I used (see the comments) :

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double val = pMsg->ControlChange(pMsg->ControlChangeIdx()); //obviously the same as you suggested
GetParam(paramIdx)->SetNormalized(val); //I used Set() instead of SetNormalized() , what difference exactly?
GetGUI()->SetParameterFromPlug(paramIdx, val, true); //I used SetControlFromPlug() instead of SetParameterFromPlug() , what difference exactly?
OnParamChange(paramIdx); //why calling this exactly?

I don't want to bother you, as you know WDL comes with very few docs, I just would like to learn WDL details as deeply as I can, so it can be helpful in the future...

[hibrasil]

//I used Set() instead of SetNormalized() , what difference exactly?

I'm sure you know the answer to this. Normalized is in the range 0-1, Set() would set the parameter's non-normalized value. IMidiMsg::ControlChange() returns a normalized value, which is why i used IParam:: SetNormalized() to update the value.

//I used SetControlFromPlug() instead of SetParameterFromPlug() what difference exactly?
IGraphics::SetParameterFromPlug() will update all controls that are linked to that parameter (could be more than one)

//OnParamChange(paramIdx); //why calling this exactly?
YourPlugin::OnParamChange() is not normally called by you, but in this case you have manually updated the parameter's value, and may want to call YourPlugin::OnParamChange() to propagate the changes to your DSP

[xhunaudio]

//I used Set() instead of SetNormalized() , what difference exactly?

I'm sure you know the answer to this. Normalized is in the range 0-1, Set() would set the parameter's non-normalized value. IMidiMsg::ControlChange() returns a normalized value, which is why i used IParam:: SetNormalized() to update the value.

//I used SetControlFromPlug() instead of SetParameterFromPlug() what difference exactly?
IGraphics::SetParameterFromPlug() will update all controls that are linked to that parameter (could be more than one)

//OnParamChange(paramIdx); //why calling this exactly?
YourPlugin::OnParamChange() is not normally called by you, but in this case you have manually updated the parameter's value, and may want to call YourPlugin::OnParamChange() to propagate the changes to your DSP

Thank you so much for the clarification Oliver,