Allow Audio Debugging

[torch2424]

Would be cool to do things like inspect each individual channel, and record audio on each channel.

Would also be nice to show live wave forms and all of that. Would be great for the debugger rebuild see #168

[torch2424]

Here are some good recording libraries:

https://github.com/higuma/web-audio-recorder-js/blob/master/lib/WebAudioRecorder.js
https://github.com/mattdiamond/Recorderjs/blob/master/src/recorder.js

Though it seems that they just get the PCM samples, and just append them to a buffer, and save that. Which we could do ourselves with the Lib callback functions.

[torch2424]

Here are some great tests on the GB APU https://github.com/LIJI32/SameSuite/tree/master/apu

Would be great to see what they are testing, and how we can visualize this.

[torch2424]

Some useful tools for audio debugging (Thanks for the suggestions DevEd and beware, and anyone else on the awesome-gbdev discord):

• Simplified register view with only the NRxx registers listed
• Wave Pattern Visualizer Example
• Volume Envelopes Example
• Channel Frequency Viewer Docs
• WaveForm Viewer Example
• Audio Recorder

Other random notes:

• NRx3+NRx4 something that could be done is the equivalent frequency in Hz and the nearest note

[torch2424]

Some resources for visualizing audio:

https://developer.mozilla.org/en-US/docs/Web/API/AnalyserNode
https://developer.mozilla.org/en-US/docs/Web/API/Web_Audio_API/Visualizations_with_Web_Audio_API
https://noisehack.com/build-music-visualizer-web-audio-api/
https://webaudioapi.com/samples/visualizer/
https://github.com/borismus/webaudioapi.com/tree/master/content/posts/visualizer

I also remember seeing a gameboy demo of someone playing zelda with audio levels, but I cant find it 😢

FOUND IT: https://codepen.io/gregh/post/recreating-legendary-8-bit-games-music-with-web-audio-api

[torch2424]

Moved the volume envelopes into it's own issue. As I don't personally see that as that important currently.