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Simulator for Open Ware Laboratory, a programmable audio effects pedal:
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OWL Simulator

Simulator for the OWL, a programmable effects pedal. All code and documentation published under the Gnu GPL, unless otherwise stated.

  1. Compilation and SDKs

1.1. VST SDK (All platforms)

To build the OwlSim as a VST, you need at least the VST Audio Plug-Ins SDK 2.4. The current available version on Steinberg website is the 3.6.0.

1.2. Windows

For Windows users, Visual Studio solutions (2008, 2010 or 2012) are available in Builds/VisualStudio20xx.

Please check your project settings to ensure the path to the VST Audio Plug-Ins SDK is correct. By default it is set to: C:\SDKs\vstsdk2.4

1.3. Linux

For Linux users, a Makefile is available in Builds/Linux.

Please check your project settings to ensure the path to the VST Audio Plug-Ins SDK is correct. By default it is set to: ~/SDKs/vstsdk2.4

1.4. Mac OS X

There is an Xcode project in Builds/MacOSX. If you are using Xcode version 4.3 or later, you may need to download and install the Core Audio Utility classes from Apple. For more details, please see the instructions here.

You may also need to set a Rez Search Path in Xcode: click on the project title, select the Build Settings tab and set a Rez Search Path to point at the directory you have created and make it recursive (e.g. /Library/Developer/CoreAudio/**).

The project can build in the AU format as well. You can enable it by setting the variable JucePlugin_Build_AU to 1 in JuceLibraryCode/AppConfig.h. You will find addtional support on the Juce Forum

  1. Write your patch

To write your patch, please use the template provided in Source/OwlPatches/TemplatePatch.hpp. You can write your code directly into it, or create a new file in Source/OwlPatches.

If you use GitHub desktop application and forked this repository, changes made in Source/OwlPatches directory will not be commited to your fork.

After creating a new file (say “Source/OwlPatches/MyPatch.hpp”), you will need to:

  • add the relevant #include to the file Source/OwlPatches/includes.h:

#include "MyPatch.hpp"

  • register it into the file Source/OwlPatches/patches.cpp:

REGISTER_PATCH(MyPatch, "My Patch");

In the patch, to get a value (float between 0 and 1) from the knobs, do as follows:

float valueA = getParameterValue(PARAMETER_A);

float valueB = getParameterValue(PARAMETER_B);

float valueC = getParameterValue(PARAMETER_C);

float valueD = getParameterValue(PARAMETER_D);

The footswitch is currently not tied to the API, but acts as a standard True Bypass switch.

  1. Test

Start up your favourite DAW, create a track, and load the OwlSim VST plugin. The build script should have copied the plugin to the right location, but if it does not appear, you may have to tell the DAW to scan or reload the VST directory.

In the OwlSim plugin you can use the drop-down box to select the patch: Template (if you have put your code into TemplatePatch.hpp) or your own patch if you have registered it in the PatchRegistry.

Compiling for Audio Units - tips

Please follow the link below for some tips on building Audio Units plugins with OWLSim:


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