Milkrack brings Winamp's Old Skool Cool visualizations from Milkdrop into your VCV Rack). Powered by ProjectM.

Just spawn the "Milkrack - embedded" module and wire its left input to your mixer's output., and you should see something like this:

The module comes in 2 flavors:

• Embedded, showing the cool visuals directly on the module.
• Windowed, rendering visualizations to a separate window.

Both flavors have the same inputs and params:

• 2 stereo audio inputs. They're normalized to the left, so you can send mono signals to just the left side.
• 1 "next preset" button and 1 "next preset" trigger input. These change the Milkdrop preset being rendered.

Non-audio signals as inputs may not give great results depending on the preset in use, as the visualization presets expect actual sound to detect BPM and perform a Fourier transform on.

The right-click menu allows you to enable automatic preset rotation, or to select a specific preset to use.

When using the windowed flavor of the module, the visuals are rendered to a separate window. That window will react to certain shortcuts:

• F, F4 or Enter will toggle full screen mode;
• Escape and Q will exit full screen mode, or, when not in full screen, will minimize the window;
• R will switch to a new preset.

Note that the window cannot be closed. To remove the window, simply delete the module in Rack.

When running under OSX, due to OpenGL incompatibilities, the Embedded flavor won't work. It's not possible to render Milkdrop presets in a window owned by VCV Rack, the OpenGL versions are not compatible. Consider using the windowed flavor instead.

• Install the GLM lib and OpenGL ES development headers, as well as autotools.
  • apt install autoconf libtool libglm-dev libgles2-mesa-dev libgl1-mesa-dev on Debian systems
  • brew install glm automate libtool pkg-config on OSX
  • If you figure out how to build this on Windows, please let me know! I don't have access to a Windows machine myself.
• Git clone Milkrack under your plugins directory
• git submodule init and git submodule update
• (cd src/deps/projectm && git apply ../projectm*.diff)
• (cd src/deps/projectm && ./autogen.sh && ./configure --with-pic --enable-static --enable-gles --disable-threading && make) to build projectM
• make Milkrack itself

If you're getting this kind of errors:

Failed to link program: error: linking with uncompiled shader
Failed to compile shader 'Fragment: blur2'. Error: 0:30(62): error: could not implicitly convert operands to arithmetic operator
0:30(12): error: no matching function for call to `min(float, error)'; candidates are:
0:30(12): error:    float min(float, float)
(...)
Failed to link program: error: linking with uncompiled shader

Try applying the patch under src/deps to projectM. Just cd src/deps/projectm and git apply ../projectm*.diff.

If you encounter errors such as:

Failed to compile shader 'Vertex: v2f_c4f'. Error: ERROR: 0:1: '' :  version '300' is not supported
ERROR: 0:1: '' : syntax error: #version
ERROR: 0:2: 'layout' : syntax error: syntax error

or others like those found in issue #2, this is due to a version incompatibility between OpenGL, OSX, projectM and Rack. It's not clear whether there's a solution, and we don't have the knowledge or the resources to fix it (no access to an OSX dev box). If you have a Mac and you know something about OpenGL, please contribute to issue #2.

If your window is just black, make sure you're sending sound into the module. No signal or non-audio signals may not trigger the preset to render anything.

If you're running OSX, the embedded flavor of the module won't work due to OpenGL version conflicts. Use the windowed mode.

If you are actually sending audio into the module, this is a sign that your shaders didn't compile. Check the standard output of Rack for errors related to invalid shaders and refer to the other troubleshooting options in this README to find matching errors.

Check that you configured the projectM build with --enable-gles.

This happens if Milkrack didn't find any Milkdrop presets to load. If you built the plugin yourself make sure that the presets folder got included in the zip file. If you downloaded the plugin from this repository's release or from the VCV plugin store, please file an issue explaining your problem.

We've done extensive testing to try to prevent this, but if this happens to you, please file an issue telling us what software you're running (Rack version, Milkrack version, OS), what you were doing, what happened, and attack Rack's log.txt and if possible Rack's standard output.

This plugin is released under LGPL.