internal static ISystem GetSystemNearestTo(Point3D currentpos,
Point3D wantedpos,
double maxfromcurpos,
double maxfromwanted,
SystemsNearestMetric routemethod,
SQLiteConnectionSystem cn,
Action <ISystem> LookedUp = null,
int limitto = 1000)
{
using (DbCommand cmd = cn.CreateSelect("Systems s",
MakeSystemQueryNamed,
where :
"x >= @xc - @maxfromcurpos " +
"AND x <= @xc + @maxfromcurpos " +
"AND z >= @zc - @maxfromcurpos " +
"AND z <= @zc + @maxfromcurpos " +
"AND x >= @xw - @maxfromwanted " +
"AND x <= @xw + @maxfromwanted " +
"AND z >= @zw - @maxfromwanted " +
"AND z <= @zw + @maxfromwanted " +
"AND y >= @yc - @maxfromcurpos " +
"AND y <= @yc + @maxfromcurpos " +
"AND y >= @yw - @maxfromwanted " +
"AND y <= @yw + @maxfromwanted ",
orderby: "(s.x-@xw)*(s.x-@xw)+(s.y-@yw)*(s.y-@yw)+(s.z-@zw)*(s.z-@zw)", // orderby distance from wanted
limit: limitto,
joinlist: MakeSystemQueryNamedJoinList))
{
cmd.AddParameterWithValue("@xw", SystemClass.DoubleToInt(wantedpos.X)); // easier to manage with named paras
cmd.AddParameterWithValue("@yw", SystemClass.DoubleToInt(wantedpos.Y));
cmd.AddParameterWithValue("@zw", SystemClass.DoubleToInt(wantedpos.Z));
cmd.AddParameterWithValue("@maxfromwanted", SystemClass.DoubleToInt(maxfromwanted));
cmd.AddParameterWithValue("@xc", SystemClass.DoubleToInt(currentpos.X));
cmd.AddParameterWithValue("@yc", SystemClass.DoubleToInt(currentpos.Y));
cmd.AddParameterWithValue("@zc", SystemClass.DoubleToInt(currentpos.Z));
cmd.AddParameterWithValue("@maxfromcurpos", SystemClass.DoubleToInt(maxfromcurpos));
//System.Diagnostics.Debug.WriteLine(cn.ExplainQueryPlanString(cmd));
using (DbDataReader reader = cmd.ExecuteReader())
{
var systems = MakeSystemEnumerable(reader, callback: LookedUp);
return(GetSystemNearestTo(systems, currentpos, wantedpos, maxfromcurpos, maxfromwanted, routemethod));
}
}
}
internal static ISystem GetSystemNearestTo(IEnumerable <ISystem> systems, // non database helper function
Point3D currentpos,
Point3D wantedpos,
double maxfromcurpos,
double maxfromwanted,
SystemsNearestMetric routemethod)
{
double bestmindistance = double.MaxValue;
ISystem nearestsystem = null;
foreach (var s in systems)
{
Point3D syspos = new Point3D(s.X, s.Y, s.Z);
double distancefromwantedx2 = Point3D.DistanceBetweenX2(wantedpos, syspos); // range between the wanted point and this, ^2
double distancefromcurposx2 = Point3D.DistanceBetweenX2(currentpos, syspos); // range between the wanted point and this, ^2
// ENSURE its withing the circles now
if (distancefromcurposx2 <= (maxfromcurpos * maxfromcurpos) && distancefromwantedx2 <= (maxfromwanted * maxfromwanted))
{
if (routemethod == SystemsNearestMetric.IterativeNearestWaypoint)
{
if (distancefromwantedx2 < bestmindistance)
{
nearestsystem = s;
bestmindistance = distancefromwantedx2;
}
}
else
{
Point3D interceptpoint = currentpos.InterceptPoint(wantedpos, syspos); // work out where the perp. intercept point is..
double deviation = Point3D.DistanceBetween(interceptpoint, syspos);
double metric = 1E39;
if (routemethod == SystemsNearestMetric.IterativeMinDevFromPath)
{
metric = deviation;
}
else if (routemethod == SystemsNearestMetric.IterativeMaximumDev100Ly)
{
metric = (deviation <= 100) ? distancefromwantedx2 : metric; // no need to sqrt it..
}
else if (routemethod == SystemsNearestMetric.IterativeMaximumDev250Ly)
{
metric = (deviation <= 250) ? distancefromwantedx2 : metric;
}
else if (routemethod == SystemsNearestMetric.IterativeMaximumDev500Ly)
{
metric = (deviation <= 500) ? distancefromwantedx2 : metric;
}
else if (routemethod == SystemsNearestMetric.IterativeWaypointDevHalf)
{
metric = Math.Sqrt(distancefromwantedx2) + deviation / 2;
}
else
{
throw new ArgumentOutOfRangeException(nameof(routemethod));
}
if (metric < bestmindistance)
{
nearestsystem = s;
bestmindistance = metric;
}
}
}
}
return(nearestsystem);
}