HTML5 Web Application Development By Example Beginner's guide

Time for action – checking the notes

We will add a call to the checkNote() method in the keyDown() method. The checkNote() method takes the name of the note as a parameter, and checks if there is a note element at the bottom of the notes panel that matches it:

function checkNote(note)
{
    if (currentNote.note == note)
    {
        var dif = getCurrentTime() - currentNote.time;
        if (dif < gracePeriod)
        {
            notesCorrect++;
            score += Math.round(10 * (gracePeriod - dif) / gracePeriod);
            currentNote.$note.css("background", "green");
            addHitEffect();
        }
    }
}

First we check the currentNote object that was set previously in updateNotes() . If its note is the same as the one the user played, then they might get some points for playing it at the correct time. To find out if they ...