Right now you are just setting the view's center to be the same position as the player every update. You just need to change that to only setting the view's center if the player is farther away from the center than you want.
For example, here is one way you could handle it
playerBoundary = 100
if (mPlayer->getPosition().x > mDrone.getCenter().x + playerBoundary)
{
newViewCenter = {mPlayer->getPosition().x - playerBoundary, mDrone.getCenter().y}
mDrone.setCenter(newViewCenter);
}
This would handle the player moving too far to the right. Just repeat something similar for the other 3 directions.