In Magic 1.6, I've changed the way audio input works for the GLSLShader module. I've separated the audio into its own module, allowing for greater flexibility which I'll explain below.
There is a new module called AudioToImage (in the
Special menu) whose sole purpose is to draw audio data by converting amplitude to brightness. Without any other modules in the scene, and just the Waveform parameter selected, it looks like this:
- AudioToImage1.png (47.58 KiB) Viewed 35057 times
What you're looking at is a "top-down" view of the Waveform. The peaks are brighter, and the troughs are darker. It's a good way to accurately represent audio with image pixels. Personally, I think this is a cool effect by itself.
You can also select the Spectrum parameter, which draws the audio spectrum in a similar way, with louder frequencies represented by brighter lines:
- AudioToImage2.png (41.92 KiB) Viewed 35057 times
Lower frequencies are on the left side, and higher frequencies are on the right side.
Ok, so what does all this mean? Well, shaders (on the graphics card) don't have a way of directly accessing audio data (on the sound card). So if you want a shader to do something fun with audio, you have to pass the audio as an image. And that's exactly what the AudioToImage module does.
Putting it all together, and using the original example from the first post (
https://www.shadertoy.com/view/ldXGzN), you can do this:
- AudioToImage3.png (103.41 KiB) Viewed 35057 times
Any shader from Shadertoy that needs audio input can be used that way. Just make sure to select both the Waveform and the Spectrum parameter.
