We have written a VST3 plugin, compiled under Visual Studio for Windows 10 & 11, tested fine with Reaper on Win 11 and Win 10, but the Transform Engine refuses to load it. The plugin shows up on the list when copied into the engine, but will not load, and no error messages are given.
Is there a developer’s guide to special requirements for the VST3 plugins for the Transform Engine?
In other words, what are the things that would allow a VST3 plugin to work in Reaper, but not on Transform Engine?
Is there a way to test on a reference Transform Engine, set to development mode, to be able to
see the load checks that may be failing?
From my experience as a plugin developer it should just work – if you don’t do anything “nonstandard”. From your post I cannot really estimate your experience level as an audio plugin developer. Is this the first time that you write an audio plugin or are you an experienced developer and trying to port a plugin that is proven to work reliably on many different hosts to the Transform Engine now?
In case you are just starting out as a developer: From my experience a “works in Reaper” state is not at all a guarantee that the plugin is working correctly. Reaper is a nice development host but it’s also very forgiving in many regards and probably not the best host to trigger all kinds of edge cases. So chances are that you are not experiencing a specific transform engine incompatibility but that you might have accidentally violated a VST3 spec. One great tool to catch all kinds of issues is pluginval. Validating your plugin on level 10 there is a good starting point to catch a lot of potential issues.
In case you are already an experienced developer and all that is no news to you, sorry for telling you basics that you probably already knew.
May I ask you which framework you used to build the plugin?
Greg, please send the logs over to us via Support and I can take a look at why the plugin scanner is having a tough time with it. There may be something in the scanner logs that gives us a better indication of the failure.
In general, there should not be anything required for transform.engine beyond it being a Windows 10 compatible VST3 plugin that can be installed and licensed offline. That said, as Janos mentioned, there have been cases where a plugin behaves correctly in one host but had an issue in ours (and vice versa), so running it through pluginval is a useful step.
I can see how a developer guide covering the some debug steps and more insight into the system would be very useful. Perhaps something we should add to the User manual, It would be great ot make it community driven too!
And thanks Janos, your input here is much appreciated (as always).