This week I made significant progress on the web interface for the Superfret system. Now when you click on a playable file, the user is prompted to submit a short form which allows the user to customize their playing experience. This includes handy features like configuring the playback speed, choosing the specific track on the midi file, and choosing between training and performance modes. Training mode will wait for the user to strum each note before continuing, allowing the user to take their time learning the song. Performance mode will not pause the song unless the pause button is clicked. Once the submit button is clicked, the bass guitar will pop up on the screen along with the notes that begin to slide into place. In order to implement pausing in the system, I had to redesign how each note was drawn on the canvas. Initially, each note was catered to by a unique thread that sleeps until it is time to play the note. Now I draw each note at the start time onto one very tall canvas and slowly slide down the entire page of notes as one whole unit. This allowed me to very quickly implement pausing. Additionally, I added a note-worthy feature of playback audio. Now a user can click on the ‘toggle listening’ button to hear their MIDI file play out loud on the website. To implement the audio I used the Tone java script library to create a noise synthesizer (I gave it settings to make it sound like a bass). Then every time a note is played on the canvas, the synthesizer uses the midi file information to sound out the notes in real time.
For next week, I would like to work on the integration between the Pi and Teensy. To do this, I would need to makes sure the web interface logic agrees with the finite state machine of Teensy and we would need to test and set up the interrupt pins and the Uart connections.