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Going to ask some really stupid questions, apologies in advance: This is mindblowing work. I'm having some trouble wrapping my head around all of it. Will lead

Going to ask some really stupid questions, apologies in advance: This is mindblowing work. I'm having some trouble wrapping my head around all of it. Will lead with the context that: A) I am not very familiar with audio programming specifics, or DSP at all. I have done some things with VST2 + VST3, and looked into LV2. B) I have very little background with C++ I am curious: 1. Is this targeted more towards the DSP and algorithm side of audio plugin development, or is there interest/use for the plugin side too (IE, generating VST/LV2 compatible interfaces)? 2. Would a byproduct of this be that you would be able to implement functionality + interact with C++ classes from other languages? Or generate C ABI's? I see the note: "Automatically generate Python bindings for a C++ class" I ask about the second one because I have been trying to work towards getting a C ABI for VST3 so that language bindings can be codegen'ed. I know VST3 works through COM so you can use that, but the alternative is to emulate the VTable layouts in C structs. This can make it easier than implementing COM in a language. ----- Edit: I also wanted to say that when reading your blogpost, the way you write C++ is very easy to understand. Not sure if it's a stylistic thing or a purposeful choice. I usually have to spend a second reading C++ code to comprehend it, but in your snippets, I was able to (mostly) grok it first pass. Same for the example code in the repo.

jcelerier 5y ago
Thanks ! I don't think those questions are stupid at all, if anything those are things I should put in the README ! > 1. Is this targeted more towards the DSP and algorithm side of audio plugin development, or is there interest/use for the plugin side too (IE, generating VST/LV2 compatible interfaces)? it does generate something compatible with VST2.x and I've been working on VST3 this week-end (and pulling a few hairs, that API is horrendous, the smallest example is a few thousand lines of codes). For LV2 I don't think it will be directly possible as LV2 requires separate .ttl files which describe the plug-in. Technically one could make a small program which from the C++ reflection, outputs the .ttl on stdout and kindly ask CMake to call it and generate the .ttl file from it. > 2. Would a byproduct of this be that you would be able to implement functionality + interact with C++ classes from other languages? yes, that's a goal, make your DSP processor in C++ and then write a small UI for it in python or QML without having to write binding code. I've tried to find ways to auto-generate a C ABI but sadly: - asm("...") only wants string literals, strings generated through constexpr don't cut it (otherwise it'd be possible and even relatively easy to generate e.g. asm(R"( .global foo_set_x .text foo_set_x: jmp _ZN3foo5set_xEi )"); to wrap for instance a foo::set_x(int) method. - I tried writing directly the binary code and appending it to the ELF sections but it seems that there's no easy way to do append to .symtab / .stringtab where the name of the symbols are without using a linker script.
- gavinray 5y ago
  > "it does generate something compatible with VST2.x and I've been working on VST3 this week-end (and pulling a few hairs, that API is horrendous, the smallest example is a few thousand lines of codes)." Oh that is awesome!!! If you want a tip about the smallest possible VST3 implementation, (and maybe you already know this) there is a class called "SingleComponentEffect", and an example called "AGainSimple" that uses it and is a fully self-contained single file full VST3 plugin: https://github.com/steinbergmedia/vst3_public_sdk/search?q=singlecomponenteffect https://github.com/steinbergmedia/vst3_public_sdk/search?q=s... Also, I spent some time trying to get VST3 SDK usable with vcpkg so you could just do: // vcpkg.json { "name": "my-audio-lib", "dependencies": [ { "name": "vst3sdk", "version>=": "3.7.3" } ] } And your CMake would just install it for you: https://github.com/microsoft/vcpkg/issues/5660#issuecomment-922508478 https://github.com/microsoft/vcpkg/issues/5660#issuecomment-... It ended up requiring more changes than this, but in the end I wound up fixing the CMake build so it spit out both the VST3 SDK (helper classes) shared lib and the almost-header-only lib ("pluginterfaces" directory). I ought to upload the patches somewhere in case it's useful for you/anyone else. > "yes, that's a goal, make your DSP processor in C++ and then write a small UI for it in python or QML without having to write binding code." That would be incredible! I think the industry focus on doing UI in C++ is a bit nutty, as an outsider (but what do I know). > "- asm("...") only wants string literals, strings generated through constexpr don't cut it (otherwise it'd be possible and even relatively easy to generate e.g." Waaay over my head!!
  - gavinray 5y ago
    Alright, I tried to push my fixed version of the VST3 SDK to Github but because it uses a ton of Git Submodules it didn't quite work. What I did instead was do: git diff > vst3sdk-no-vstgui-cmake-compatible.patch Which has a patch with the changes (EXCEPT for the file "Config.cmake.in") https://github.com/GavinRay97/vst3sdk/blob/master/vst3sdk-no-vstgui-cmake-compatible.patch https://github.com/GavinRay97/vst3sdk/blob/master/vst3sdk-no... I also just said fuck it and zipped up the whole project, you can download it here: https://github.com/GavinRay97/vst3sdk/blob/master/vst3sdk.zip https://github.com/GavinRay97/vst3sdk/blob/master/vst3sdk.zi... With this fixed version, using the VST3 SDK becomes much much easier. All you have to do is add it as a vendored subproject in CMake: project(VST3Example CXX) add_subdirectory(vendor/vst3sdk) add_executable(VST3Example src/main.cpp) target_compile_features(VST3Example PRIVATE cxx_std_20) target_include_directories(VST3Example PRIVATE vendor/vst3sdk) # This links SDK if you want to use the "SingleComponentEffect" target_link_libraries(VST3Example PUBLIC sdk) Where the project looks something like $ tree -L 2 . ├── CMakeLists.txt ├── src │ └── main.cpp └── vendor └── vst3sdk And then here's your VST3 in "main.cpp": #include "public.sdk/source/main/pluginfactory.h" #include "public.sdk/source/vst/vstsinglecomponenteffect.h" using namespace Steinberg; using namespace Steinberg::Vst; class MyVST : Steinberg::Vst::SingleComponentEffect {}; __declspec(dllexport) IPluginFactory* GetPluginFactory() {} Hope this helps! I am relatively clueless about C++ though!

jcelerier 5y ago

Thanks ! I don't think those questions are stupid at all, if anything those are things I should put in the README ! > 1. Is this targeted more towards the DSP and algorithm side of audio plugin development, or is there interest/use for the plugin side too (IE, generating VST/LV2 compatible interfaces)? it does generate something compatible with VST2.x and I've been working on VST3 this week-end (and pulling a few hairs, that API is horrendous, the smallest example is a few thousand lines of codes). For LV2 I don't think it will be directly possible as LV2 requires separate .ttl files which describe the plug-in. Technically one could make a small program which from the C++ reflection, outputs the .ttl on stdout and kindly ask CMake to call it and generate the .ttl file from it. > 2. Would a byproduct of this be that you would be able to implement functionality + interact with C++ classes from other languages? yes, that's a goal, make your DSP processor in C++ and then write a small UI for it in python or QML without having to write binding code. I've tried to find ways to auto-generate a C ABI but sadly: - asm("...") only wants string literals, strings generated through constexpr don't cut it (otherwise it'd be possible and even relatively easy to generate e.g. asm(R"( .global foo_set_x .text foo_set_x: jmp _ZN3foo5set_xEi )"); to wrap for instance a foo::set_x(int) method. - I tried writing directly the binary code and appending it to the ELF sections but it seems that there's no easy way to do append to .symtab / .stringtab where the name of the symbols are without using a linker script.

gavinray 5y ago
> "it does generate something compatible with VST2.x and I've been working on VST3 this week-end (and pulling a few hairs, that API is horrendous, the smallest example is a few thousand lines of codes)." Oh that is awesome!!! If you want a tip about the smallest possible VST3 implementation, (and maybe you already know this) there is a class called "SingleComponentEffect", and an example called "AGainSimple" that uses it and is a fully self-contained single file full VST3 plugin: https://github.com/steinbergmedia/vst3_public_sdk/search?q=singlecomponenteffect https://github.com/steinbergmedia/vst3_public_sdk/search?q=s... Also, I spent some time trying to get VST3 SDK usable with vcpkg so you could just do: // vcpkg.json { "name": "my-audio-lib", "dependencies": [ { "name": "vst3sdk", "version>=": "3.7.3" } ] } And your CMake would just install it for you: https://github.com/microsoft/vcpkg/issues/5660#issuecomment-922508478 https://github.com/microsoft/vcpkg/issues/5660#issuecomment-... It ended up requiring more changes than this, but in the end I wound up fixing the CMake build so it spit out both the VST3 SDK (helper classes) shared lib and the almost-header-only lib ("pluginterfaces" directory). I ought to upload the patches somewhere in case it's useful for you/anyone else. > "yes, that's a goal, make your DSP processor in C++ and then write a small UI for it in python or QML without having to write binding code." That would be incredible! I think the industry focus on doing UI in C++ is a bit nutty, as an outsider (but what do I know). > "- asm("...") only wants string literals, strings generated through constexpr don't cut it (otherwise it'd be possible and even relatively easy to generate e.g." Waaay over my head!!
- gavinray 5y ago
  Alright, I tried to push my fixed version of the VST3 SDK to Github but because it uses a ton of Git Submodules it didn't quite work. What I did instead was do: git diff > vst3sdk-no-vstgui-cmake-compatible.patch Which has a patch with the changes (EXCEPT for the file "Config.cmake.in") https://github.com/GavinRay97/vst3sdk/blob/master/vst3sdk-no-vstgui-cmake-compatible.patch https://github.com/GavinRay97/vst3sdk/blob/master/vst3sdk-no... I also just said fuck it and zipped up the whole project, you can download it here: https://github.com/GavinRay97/vst3sdk/blob/master/vst3sdk.zip https://github.com/GavinRay97/vst3sdk/blob/master/vst3sdk.zi... With this fixed version, using the VST3 SDK becomes much much easier. All you have to do is add it as a vendored subproject in CMake: project(VST3Example CXX) add_subdirectory(vendor/vst3sdk) add_executable(VST3Example src/main.cpp) target_compile_features(VST3Example PRIVATE cxx_std_20) target_include_directories(VST3Example PRIVATE vendor/vst3sdk) # This links SDK if you want to use the "SingleComponentEffect" target_link_libraries(VST3Example PUBLIC sdk) Where the project looks something like $ tree -L 2 . ├── CMakeLists.txt ├── src │ └── main.cpp └── vendor └── vst3sdk And then here's your VST3 in "main.cpp": #include "public.sdk/source/main/pluginfactory.h" #include "public.sdk/source/vst/vstsinglecomponenteffect.h" using namespace Steinberg; using namespace Steinberg::Vst; class MyVST : Steinberg::Vst::SingleComponentEffect {}; __declspec(dllexport) IPluginFactory* GetPluginFactory() {} Hope this helps! I am relatively clueless about C++ though!