/// <summary>
/// Sorts structures by distance. Both vertical and horizontal distances are accounted for.
/// </summary>
/// <param name="obj">The other RelativePosition object to compare with.</param>
/// <returns>-1 if this structure is less than obj, 0 if they are equal, and 1 if obj is greater than this structure.</returns>
public int CompareTo(object obj)
{
RelativePosition r = (RelativePosition)obj;
double instanceDistance = distance + vDistance;
double objDistance = r.distance + r.vDistance;
if (instanceDistance > objDistance)
{
return(1);
}
if (instanceDistance < objDistance)
{
return(-1);
}
return(0);
}
//Returns a RelativePosition structure that defines the
//position of jbect 2 to object 1, from the perspective of object 1.
public static RelativePosition getPosition(double x1, double y1, double z1, int dir1,
double x2, double y2, double z2, int dir2,
bool isObject)
{
RelativePosition r = new RelativePosition();
r.distance = getDistanceBetween(x1, y1, x2, y2);
r.degrees = GetDegreesBetween(x1, y1, x2, y2);
int f1 = getDegreeValue(dir1 - 80);
int f2 = getDegreeValue(dir1 + 80);
Rotation rDir = getShortestRotation(dir1, r.degrees);
r.isAhead = inRange(f1, f2, r.degrees);
//Since front view is at dir1, back view is dir1+180, and the
//respective spread.
r.isBehind = inRange(getDegreeValue(dir1 + 180 - 80),
getDegreeValue(dir1 + 180 + 80),
r.degrees);
////check for view
//isObject is true if the target object is
//something that is not a flying object. eg. a SAM battery,
//in which case views will not be relevant.
if (!isObject)
{
int oD = getDegreeValue(r.degrees + 180);
////since d is the degree at which object1 must face to be on a
////collision path with object2, d+180 is the exact
////degree mark object2 must be on to face object1 on a collision path.
r.isNoseFacing = inRange(getDegreeValue(oD - 30),
getDegreeValue(oD + 30),
dir2);
oD -= 180;
r.isTailFacing = inRange(getDegreeValue(oD - 30),
getDegreeValue(oD + 30),
dir2);
r.isWingFacing = !r.isNoseFacing && !r.isTailFacing;
} //if !isObject
r.degreesDifference = getDifference(dir1, r.degrees);
if (rDir == Rotation.counterClockwise)
{
r.relativeDegrees = 360 - r.degreesDifference;
}
else if (rDir == Rotation.clockwise)
{
r.relativeDegrees = r.degreesDifference;
}
else if (rDir == Rotation.equal)
{
r.relativeDegrees = 180;
}
else if (rDir == Rotation.stationary)
{
r.relativeDegrees = 0;
}
r.clockMark = getClockValue(r.relativeDegrees);
r.vDistance = z2 - z1;
return(r);
}
