I posted the changes I made to codepen,
The gitter support people told me not to post long code there so maybe they removed what I put there for you,
The changes to the interface function were of this sort,
.append(“circle:svg”) etc. and after that I could see your game working fine, but noticed when the duplicate tones did not show up as well. I think you
could fix that by making a longer timeout. I did not make a grouping on
your svgs but probably that will help.
If you are not familiar with grouping svgs, here are two good sources to read.
"However, unlike the other selection methods, selection.data defines data per-group rather than per-element: data is expressed as an array of values for the group, or a function that returns such an array. Thus, a grouped selection has correspondingly grouped data! " from https://bost.ocks.org/mike/selection
look for this line in particular,
var CircleGroup = svgContainer.append(“g”);
Hope that helps you. I am still working on figuring out the setTimeout and
setInterval game loop that will make my game work. If you have any suggestions for me I will appreciate it.