Piano Roll editor should display 12 tones per octave
The Piano Roll Editor should be changed so that each semitone is displayed in its own row instead of the current system where only the 7 tones of the C scale are given rows and the other tones are wedged in between them.
The 12 tone grid is the layout style used by many commercial program's piano rolls. By having one row per tone, the user can better understand the relation between space and pitch. The current system awkwardly inserts semitones between scale degrees outside of bar lines. If you write a chromatic scale, instead of it going up evenly one row at a time, there are noticeable discontinuities between B & C and E & F. Adopting this system would also allow darkening the rows of the black keys, making it more obvious which notes blocks represent which pitches.
I'd also like to change the vertical scaling mechanism in the editor which right now simply performs a transform() on the rendered graphics - this is both inefficient and leads to scaling artifacts. It would be better to establish a semitone width and then use that to layout the grid vertically.