Michael Gogins
https://github.com/gogins
http://michaelgogins.tumblr.com

This project provides Csound plugin opcodes for hosting VST3 plugin instruments and effects in Csound.

These opcodes are a port of the older vst4cs opcodes, which support only the VST2 protocol, to the newer and more capable VST3 protocol. The opcodes have more or less the same behavior as the vst4cs opcodes.

These opcodes are designed to be cross-platform and to run at least on Linux, Windows, and macOS.

csound-vst3-opcodes is non-commercial software and is licensed under GPLv3, as is the VST3 SDK; GPLv3, in turn, is compatible with Csound, which has a LGPLv2.1 license that permits relicensing to any later version of the GPL.

Do not directly build the VST3 SDK. It functions as a subdirectory of the csound-vst3-plugins project. There are platform-specific shell scripts for building this project. The following instructions are for macOS. Just substitute windows or linux for macos in the script filenames, depending on your platform.

1. Run update-submodules.bash, which ensures that the Git submodules used by this project have been initialized and updated.

2. Run clean-build-macos.bash. It should finish with a list showing the new Csound plugin shared library.

3. Run zip-macos.bash to create a Zip file containing the shared library,

Copy the vst3-opcodes shared library to your Csound plugin directory, which is specified in the OPCODE6DIR64 environment variable. Or, preferably, create a symbolic link in the OPCODE6DIR64 directory to the vst3-plugins shared library.

The VST3 opcodes have exactly the same names as the vst4cs opcodes, except that in each opcode name, "vst" is replaced by "vst3", for example "vstinit" becomes "vst3init".

The VST3 opcodes behave more or less the same way as the vst4cs opcodes, except that the VST3 protocol applies parameter changes with sample frame accuracy and interpolation.

For a reference to the opcodes, see their README.md.

On macOS, the vst3-opcodes shared library is now built as a universal binary (including both x86-64 CPU architecture and arm64 CPU architecture).

The handling of fractional pitches (i.e. fractional MIDI key numbers) in this project has been corrected and simplified.

Program changes are now working, at least for the sample plugins in the VST3 SDK.

Loading presets has been implemented using the vst3initpreset opcode.

There was a bug in that the VST3 plugin busses were not being properly activated, causing some VST3 plugins not to process audio. This has been fixed.

The sample VST3 plugins build by the VST3 SDK are now included in releases.

The directory structure of this project has been simplified.

The build system has been corrected and simplified.