/// <summary>
/// Update the 'sunsInfo' list and the 'mainSun', 'solarFluxTotal' variables.
/// Uses discrete or analytic (for high timewarp speeds) evaluation methods based on the isAnalytic bool.
/// Require the 'visibleBodies' variable to be set.
/// </summary>
// at the two highest timewarp speed, the number of sun visibility samples drop to the point that
// the quantization error first became noticeable, and then exceed 100%, to solve this :
// - we switch to an analytical estimation of the sunlight/shadow period
// - atmo_factor become an average atmospheric absorption factor over the daylight period (not the whole day)
public static void UpdateSunsInfo(VesselData vd, Vector3d vesselPosition)
{
Vessel v = vd.Vessel;
double lastSolarFlux = 0.0;
vd.sunsInfo = new List <SunInfo>(Sim.suns.Count);
vd.solarFluxTotal = 0.0;
vd.rawSolarFluxTotal = 0.0;
foreach (Sim.SunData sunData in Sim.suns)
{
SunInfo sunInfo = new SunInfo(sunData);
if (vd.isAnalytic)
{
// get sun direction and distance
Lib.DirectionAndDistance(vesselPosition, sunInfo.sunData.body, out sunInfo.direction, out sunInfo.distance);
// analytical estimation of the portion of orbit that was in sunlight, current limitations :
// - the result is dependant on the vessel altitude at the time of evaluation,
// consequently it gives inconsistent behavior with highly eccentric orbits
// - this totally ignore the orbit inclinaison, polar orbits will be treated as equatorial orbits
sunInfo.sunlightFactor = 1.0 - Sim.ShadowPeriod(v) / Sim.OrbitalPeriod(v);
// get atmospheric absorbtion
// for atmospheric bodies whose rotation period is less than 120 hours,
// determine analytic atmospheric absorption over a single body revolution instead
// of using a discrete value that would be unreliable at large timesteps :
if (vd.inAtmosphere)
{
sunInfo.atmoFactor = Sim.AtmosphereFactorAnalytic(v.mainBody, vesselPosition, sunInfo.direction);
}
else
{
sunInfo.atmoFactor = 1.0;
}
}
else
{
// determine if in sunlight, calculate sun direction and distance
sunInfo.sunlightFactor = Sim.IsBodyVisible(v, vesselPosition, sunData.body, vd.visibleBodies, out sunInfo.direction, out sunInfo.distance) ? 1.0 : 0.0;
// get atmospheric absorbtion
sunInfo.atmoFactor = Sim.AtmosphereFactor(v.mainBody, vesselPosition, sunInfo.direction);
}
// get resulting solar flux in W/m²
sunInfo.rawSolarFlux = sunInfo.sunData.SolarFlux(sunInfo.distance);
sunInfo.solarFlux = sunInfo.rawSolarFlux * sunInfo.sunlightFactor * sunInfo.atmoFactor;
// increment total flux from all stars
vd.rawSolarFluxTotal += sunInfo.rawSolarFlux;
vd.solarFluxTotal += sunInfo.solarFlux;
// add the star to the list
vd.sunsInfo.Add(sunInfo);
// the most powerful star will be our "default" sun. Uses raw flux before atmo / sunlight factor
if (sunInfo.rawSolarFlux > lastSolarFlux)
{
lastSolarFlux = sunInfo.rawSolarFlux;
vd.mainSun = sunInfo;
}
}
vd.sunlightFactor = 0.0;
foreach (SunInfo sunInfo in vd.sunsInfo)
{
sunInfo.fluxProportion = sunInfo.rawSolarFlux / vd.rawSolarFluxTotal;
vd.sunlightFactor += sunInfo.SunlightFactor * sunInfo.fluxProportion;
}
// avoid rounding errors
if (vd.sunlightFactor > 0.99)
{
vd.sunlightFactor = 1.0;
}
}
/// <summary>
/// Update the 'sunsInfo' list and the 'mainSun', 'solarFluxTotal' variables.
/// Uses discrete or analytic (for high timewarp speeds) evaluation methods based on the isAnalytic bool.
/// Require the 'visibleBodies' variable to be set.
/// </summary>
// at the two highest timewarp speed, the number of sun visibility samples drop to the point that
// the quantization error first became noticeable, and then exceed 100%, to solve this:
// - we switch to an analytical estimation of the sunlight/shadow period
// - atmo_factor become an average atmospheric absorption factor over the daylight period (not the whole day)
public static void UpdateSunsInfo(VesselData vd, Vector3d vesselPosition, double elapsedSeconds)
{
Vessel v = vd.Vessel;
double lastSolarFlux = 0.0;
vd.sunsInfo = new List <SunInfo>(Sim.suns.Count);
vd.solarFluxTotal = 0.0;
vd.rawSolarFluxTotal = 0.0;
foreach (Sim.SunData sunData in Sim.suns)
{
SunInfo sunInfo = new SunInfo(sunData);
if (vd.isAnalytic)
{
// get sun direction and distance
Lib.DirectionAndDistance(vesselPosition, sunInfo.sunData.body, out sunInfo.direction, out sunInfo.distance);
// analytical estimation of the portion of orbit that was in sunlight.
// it has some limitations, see the comments on Sim.ShadowPeriod
if (Settings.UseSamplingSunFactor)
{
// sampling estimation of the portion of orbit that is in sunlight
// until we will calculate again
sunInfo.sunlightFactor = Sim.SampleSunFactor(v, elapsedSeconds);
}
else
{
// analytical estimation of the portion of orbit that was in sunlight.
// it has some limitations, see the comments on Sim.ShadowPeriod
sunInfo.sunlightFactor = 1.0 - Sim.ShadowPeriod(v) / Sim.OrbitalPeriod(v);
}
// get atmospheric absorbtion
// for atmospheric bodies whose rotation period is less than 120 hours,
// determine analytic atmospheric absorption over a single body revolution instead
// of using a discrete value that would be unreliable at large timesteps :
if (vd.inAtmosphere)
{
sunInfo.atmoFactor = Sim.AtmosphereFactorAnalytic(v.mainBody, vesselPosition, sunInfo.direction);
}
else
{
sunInfo.atmoFactor = 1.0;
}
}
else
{
// determine if in sunlight, calculate sun direction and distance
sunInfo.sunlightFactor = Sim.IsBodyVisible(v, vesselPosition, sunData.body, vd.visibleBodies, out sunInfo.direction, out sunInfo.distance) ? 1.0 : 0.0;
// get atmospheric absorbtion
sunInfo.atmoFactor = Sim.AtmosphereFactor(v.mainBody, vesselPosition, sunInfo.direction);
}
// get resulting solar flux in W/m²
sunInfo.rawSolarFlux = sunInfo.sunData.SolarFlux(sunInfo.distance);
sunInfo.solarFlux = sunInfo.rawSolarFlux * sunInfo.sunlightFactor * sunInfo.atmoFactor;
// increment total flux from all stars
vd.rawSolarFluxTotal += sunInfo.rawSolarFlux;
vd.solarFluxTotal += sunInfo.solarFlux;
// add the star to the list
vd.sunsInfo.Add(sunInfo);
// the most powerful star will be our "default" sun. Uses raw flux before atmo / sunlight factor
if (sunInfo.rawSolarFlux > lastSolarFlux)
{
lastSolarFlux = sunInfo.rawSolarFlux;
vd.mainSun = sunInfo;
}
}
vd.sunlightFactor = 0.0;
foreach (SunInfo sunInfo in vd.sunsInfo)
{
sunInfo.fluxProportion = sunInfo.rawSolarFlux / vd.rawSolarFluxTotal;
vd.sunlightFactor += sunInfo.SunlightFactor * sunInfo.fluxProportion;
}
// avoid rounding errors
if (vd.sunlightFactor > 0.99)
{
vd.sunlightFactor = 1.0;
}
}