Jessie

Closes #10

This should play a sound when a note crosses the receptor while the song is playing.

Performing a reversible action adds it to the undo stack. If the user presses undo, the change is reversed, and it's moved to the redo stack. Likewise the user can...

The user should be able to drag their cursor to select a group of notes. If the user is holding down shift or control, whatever is selected should be added...

The notefield only supports drawing tap notes at the moment. It should also draw holds. The user should also be able to place holds by holding down the column key...

- [x] Draw the beat line paths in bulk (one `beginPath` and `closePath` call for all measure lines, beat lines, fractional lines) - [ ] Resize the noteskin images when...

The WebAudio API gives us more control over the music playback. For example, we can schedule when the music should start playing, which would help fix an issue where sometimes...

Pasting notes should place them at the current scroll position. For now, let's just remove any notes in the paste region before pasting, and not worry about trying to merge...

When the user presses the backspace or delete key while notes are selected those notes should be removed.

Resources: - https://developer.mozilla.org/en-US/docs/Web/API/Window/beforeunload_event#see_also - https://github.com/GoogleChromeLabs/page-lifecycle