barrelElevationForTarget method
Returns the barrel elevation (relative to look-angle) needed to hit
a target at targetDistance.
Implementation
Angular barrelElevationForTarget(Shot shot, Distance targetDistance) {
final distFt = _toFeet(targetDistance);
final bcShot = _toBcShot(shot);
final totalRad = _engine.findZeroAngleShot(bcShot, distFt);
return Angular(totalRad - shot.lookAngle.in_(Unit.radian), Unit.radian);
}