/// <summary>
/// Generates Data for a star based on it's spectral type and populates it with the data.
/// </summary>
/// <remarks>
/// This function randomly generates the Radius, Temperature, Luminosity, Mass and Age of a star and then returns a star populated with those generated values.
/// What follows is a brief description of how that is done for each data point:
/// <list type="Bullet">
/// <item>
/// <b>Temperature:</b> The Temp. of the star is obtained by using the Randon.Next(min, max) function to get a random Temp. in the range a star of the given
/// spectral type.
/// </item>
/// <item>
/// <b>Luminosity:</b> The Luminosity of a star is calculated by using the RNG_NextDoubleRange() function to get a random Luminosity in the range a star of the
/// given spectral type.
/// </item>
/// <item>
/// <b>Age:</b> The possible ages for a star depend largely on its mass. The bigger and heaver the star the more pressure is put on its core where fusion occur
/// which increases the rate that it burns Hydrogen which reduces the life of the star. The Big O class stars only last a few million years before either
/// going Hyper Nova or devolving into a class B star. on the other hand a class G star (like Sol) has a life expectancy of about 10 billion years while a
/// little class M star could last 100 billion years or more (hard to tell given that the Milky way is 13.2 billion years old and the universe is only
/// about a billion years older then that). Given this we first use the mass of the star to produce a number between 0 and 1 that we can use to pick a
/// possible age from the range (just like all the above). To get the number between 0 and 1 we use the following formula:
/// <c>1 - Mass / MaxMassOfStarOfThisType</c>
/// </item>
/// </list>
/// </remarks>
/// <param name="starMVDB">The SystemBodyDB of the star.</param>
/// <param name="spectralType">The Spectral Type of the star.</param>
/// <param name="randomSelection">Random selection to generate consistent values.</param>
/// <returns>A StarInfoDB Populated with data generated based on Spectral Type and SystemBodyDB information provided.</returns>
private StarInfoDB GenerateStarInfo(MassVolumeDB starMVDB, SpectralType spectralType, double randomSelection)
{
double maxStarAge = _galaxyGen.Settings.StarAgeBySpectralType[spectralType].Max;
StarInfoDB starData = new StarInfoDB {// for star age we will make it proportional to the inverse of the stars mass ratio (for that type of star).
// while this will produce the same age for the same mass/type of star the chances of getting the same
// mass/type are tiny. Tho there will still be the obvious inverse relationship here.
Age = (1 - starMVDB.Mass / _galaxyGen.Settings.StarMassBySpectralType[spectralType].Max) * maxStarAge,
SpectralType = spectralType,
Temperature = (uint)Math.Round(GMath.SelectFromRange(_galaxyGen.Settings.StarTemperatureBySpectralType[spectralType], randomSelection)),
Luminosity = (float)GMath.SelectFromRange(_galaxyGen.Settings.StarLuminosityBySpectralType[spectralType], randomSelection)
};
// Generate a string specifying the full spectral class form a star.
// start by getting the sub-division, which is based on temp.
double sub = starData.Temperature / _galaxyGen.Settings.StarTemperatureBySpectralType[starData.SpectralType].Max; // temp range from 0 to 1.
starData.SpectralSubDivision = (ushort)Math.Round((1 - sub) * 10); // invert temp range as 0 is hottest, 9 is coolest.
// now get the luminosity class
//< @todo For right now everthing is just main sequence. see http://en.wikipedia.org/wiki/Stellar_classification
// on how this should be done. For right now tho class V is fine (its just flavor text).
starData.LuminosityClass = LuminosityClass.V;
// finally add them all up to get the class string:
starData.Class = starData.SpectralType + starData.SpectralSubDivision.ToString() + "-" + starData.LuminosityClass;
return(starData);
}
public static void OrbCharsArgumentException(SpectralType spectralType)
{
if (!Enum.IsDefined(typeof(SpectralType), spectralType))
{
throw new ArgumentOutOfRangeException
("Возможное значение спектрального класса: A, B, F, G, K, M, O");
}
}
public Star(int id, string starName, SpectralType spectralType,
float magnitude, float rectascension, float declinationAngle,
float temperature, float distance) : this(starName, spectralType,
magnitude, rectascension, declinationAngle, temperature, distance)
{
Id = id;
NotifyPropertyChanged("Id");
}
public Star(int id, string starName, SpectralType spectralType, float magnitude,
float rectascension, float declinationAngle, float temperature,
float distance, ObservableDictionary <int, Planet> planets) :
this(id, starName, spectralType, magnitude, rectascension, declinationAngle,
temperature, distance)
{
_planets = planets;
NotifyPropertyChanged("Planets");
}
public Star(string name, double radius, uint temp, float luminosity, SpectralType spectralType, StarSystem system)
{
Name = name;
Position.System = system;
Position.X = 0;
Position.Y = 0;
Temperature = temp;
Luminosity = luminosity;
SpectralType = spectralType;
Radius = radius;
Class = SpectralType.ToString();
Planets = new BindingList <SystemBody>();
SupportsPopulations = false;
}
public Star(string name, double radius, uint temp, float luminosity, SpectralType spectralType, StarSystem system)
{
Name = name;
Position.System = system;
Position.X = 0;
Position.Y = 0;
Temperature = temp;
Luminosity = luminosity;
SpectralType = spectralType;
Radius = radius;
Class = SpectralType.ToString();
Planets = new BindingList<SystemBody>();
SupportsPopulations = false;
}
public Star(string starName, SpectralType spectralType, float magnitude,
float rectascension, float declinationAngle,
float temperature, float distance) : this()
{
OrbNameArgumentException(starName, "планеты");
OrbCharsArgumentException(spectralType);
OrbCharsArgumentException(rectascension, "прямого восхождения звезды");
OrbCharsArgumentException(temperature, "температуры звезды");
OrbCharsArgumentException(distance, "расстояния до звезды");
_name = starName;
NotifyPropertyChanged("Name");
_spectralType = spectralType;
NotifyPropertyChanged("SpectralType");
_magnitude = magnitude;
NotifyPropertyChanged("Magnitude");
_rectascension = rectascension;
NotifyPropertyChanged("Rectascension");
_declinationAngle = declinationAngle;
NotifyPropertyChanged("DeclinationAngle");
_temperature = temperature;
NotifyPropertyChanged("Temperature");
_distance = distance;
NotifyPropertyChanged("Distance");
}
/// <summary>
/// Creates a star entity in the system.
/// Does not initialize an orbit.
/// </summary>
public Entity CreateStar(StarSystem system, double mass, double radius, double age, string starClass, double temperature, float luminosity, SpectralType spectralType, string starName = null)
{
double tempRange = temperature / _galaxyGen.Settings.StarTemperatureBySpectralType[spectralType].Max; // temp range from 0 to 1.
ushort subDivision = (ushort)Math.Round((1 - tempRange) * 10);
LuminosityClass luminosityClass = LuminosityClass.V;
if (starName == null)
{
starName = system.NameDB.DefaultName;
}
int starIndex = system.GetAllEntitiesWithDataBlob <StarInfoDB>().Count;
starName += " " + (char)('A' + starIndex) + " " + spectralType + subDivision + luminosityClass;
MassVolumeDB starMassVolumeDB = MassVolumeDB.NewFromMassAndRadius(mass, radius);
StarInfoDB starInfoDB = new StarInfoDB {
Age = age, Class = starClass, Luminosity = luminosity, SpectralType = spectralType, Temperature = temperature, LuminosityClass = luminosityClass, SpectralSubDivision = subDivision
};
PositionDB starPositionDB = new PositionDB(new Vector3(0, 0, 0), system.Guid);
NameDB starNameDB = new NameDB(starName);
OrbitDB starOrbitDB = new OrbitDB();
SensorProfileDB emmisionSignature = SensorProcessorTools.SetStarEmmisionSig(starInfoDB, starMassVolumeDB);
return(new Entity(system, new List <BaseDataBlob> {
starOrbitDB, starMassVolumeDB, starInfoDB, starNameDB, starPositionDB, emmisionSignature
}));
}
