That would not be a gap - a gap is a lack of price quotation
This is a divergence.
If the colors change red and green that is a chop warning
If they are different AND the are going in different directions (divergence) that is even a stronger choppy warning.
I prefer to use Blue and Yellow like I show on the style screen in the trading room better than use green and red so your not thinking up and down - as the direction is not the focus - the focus is implied volatility not lining up with market trend.
This is not a “trend indicator” it is a choppy market warning indicator