Hi,

For a project with University I am trying to create a VST. The starting point is to extend the VstXSynth to have more wave forms (which I have done, whether its correct is a completely different thing haha) as well as an ADSR envelope and simple Delay effect.

In terms of the delay, I have been told I can implement the delay sample code into the vstxsynth, however for whatever reason and whatever I try I can't for the life of me get it to work.

As for the envelope I don't even know where to start. So my question is simple, does anyone have any decent points of reference for a complete beginner to do these kinds of things, or any useful samples explaining the basics?

Much appreciated,
Tom

Make it in synthedit export the modules and look at the code. This should give you an idea of how the code works in c+.

I've seen synthedit before, never used it though. Is it easy to use?

and thankyou.

From earlier experience, my impression was that SynthEdit doesn't emit C++ source code. Am I mistaken? Since when?

you're not mistaken.

Yeah I think synthedit tapes a bunch of DLLs together so all the code is already compiled.

Some tips:

Delay: Use a "circular buffer" (essentially an array with the read/write pointers skipping back to the start once the pass the end). Make sure you zero your memory in the constructor.

Envelope: Just code a class that outputs a value that increases/decreases over time (depending on which shape you want).

If you're having a hard time still, you might want to improve your knowledge of C++ too.

with the envelope,
you just want to multiply the oscillators stream with how loud u want it to be.
Release is problematic,
I dunno how it's done really.
But essentially just make an amplitude curve that is MIDI dependant and multiply with stream.
With delay, write to memory and subtract your number of samples which is length
when u read it.
There was some other thing that might be neccessary to avoid clicks. It involved the counting at the end of the buffer.
If your delay is clicking, let me know and I will look what I did to mine.
All success!

edit-also with the delay you need to feedback, for echo

Brilliant, thanks for all the feedback. Appreciate it.

So far, I've implemented a lot of the code for Delay, taking into account the frequency amount (as mentioned above). I'm struggling a bit in terms of what needs to go in the process function. The ADelay sample appears to implement the process within the While Loop, am I correct in thinking this?

You can export C++ code from synthedit modules. Also you can write new modules in C++.

To export a module into c++ source code right click and select build code skeleton.

This of course is written for synthedit but you could see how to write it for a different app by looking at the source to get an idea.

Yes, the audio host passes a chunk of samples to the plugin to process. The While Loop in the example is where the sound is actually processed. The rest of the code is basically used to setup the controls (e.g., what happens when you click on a slider to increase/decrease the value). For the most part, you want to keep things as efficient as possible within the loop.

all this does is give the code for a blank module with the pins as per the module you selected - no code is generated for the actual functionality. it is meant as a tool to help 'port' sems from sdk2 to sdk3 ...