VST3 problem with current JUCE on master

Audio Plugins
1

VST3 audio plug-in in REAPER (64 bit on Mac).

JucePlugin_PreferredChannelConfigurations set to {1, 1}, {2, 2}

As soon as I start playback, I get a prepareToPlay() callback in which getBusesLayout() returns a layout that has 0 channels for both input and output, instead of 1 or 2.

This can be easily reproduced creating a project from scratch in Projucer:

  1. Create a default audio plug-in project in Projucer

  2. Enable VST3 build (and specify correct VST SDK path)

  3. Set “{1, 1}, {2, 2}” in the box that specifies the supported channels configurations

  4. Enter the following line in prepareToPlay():

    DBG (String::formatted ("In: %d, Out: %d", getBusesLayout().getMainInputChannels(), getBusesLayout().getMainOutputChannels()));

  5. Now open Xcode, set REAPER64 as the executable to launch then build and run the project

  6. Create an empty track in REAPER, and insert the plug-in there.

  7. Watch the output emitted on the debug console, it should be as follows:

     JUCE v4.3.0
 In: 1, Out: 1
 In: 2, Out: 2
 In: 2, Out: 2
 In: 2, Out: 2
 In: 2, Out: 2

  8. Now press Play and watch the following line being printed:

     In: 0, Out: 0

The expected behavior would instead be to receive another prepareToPlay() with {2, 2} upon playback start, or none at all, since the latest received before that has already set the correct {2, 2} layout

2

Hmmm tried a while now to re-produce this. Do you know what I’m doing differently?

3

Are you on master?
I haven’t had time to test it with develop yet, it may be resolved there… in which case, can you point me to the commit which I have to cherry-pick for an hotfix?

Otherwise, the only difference I found is that you are getting the number of channels in main bus a little different than my case (but I guess it is equivalent)

4

No on develop. We only put out critical hotfixes on master. So you may want to cherry pick some of the VST3 changes I did recently.

I did both. Just couldn’t remember the exact code line you had when I did the video. But before the video I copy&pasted your line of code.

5

Hmmm just saw the title now… embarrassing. Anyway, we probably won’t push those fixes to master just yet.

6

You seem to already know which “those fixes” are, while I am seeing that a number of commits have affected the VST3 wrapper since latest master update.
Are you able to tell me, which commit should I cherry-pick for an hotfix to be applied on my private juce repo, which is currently on master?

7

Not sure really.

It’s probably this one:
63a71ff20dc6643e0636beaa6373eb4ec7e5f826

Might also be this one:
910cab77a19b5ea47357a4ffc3b64135b381ae92

8

Ok thanks, I will try them

9

This one seems to have solved the problem completely, thanks.
I haven’t tested the other one because I didn’t seem to need it.

While we are at it regarding channels, etc., regarding VST2 instead, have you had a chance to look at this other topic?