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orbitalkiller: fixed future orbut velocity and hyperbolic position ca…
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…lculation
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Andrey Borunov committed Jun 16, 2016
1 parent 6b353ef commit 4e2f167
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Showing 3 changed files with 38 additions and 24 deletions.
4 changes: 2 additions & 2 deletions ...killer/src/main/scala/com/github/dunnololda/scageprojects/orbitalkiller/PolygonShip.scala
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Expand Up @@ -1125,8 +1125,8 @@ abstract class PolygonShip(
val x = new_e.orbitalPointAfterTime(deactivate_point_relative + planet_coord, time_since_deactivation_msec, or.ccw)
}*/
currentState.coord = new_e.orbitalPointAfterTime(deactivate_point_relative + planet_coord, time_since_deactivation_msec, or.ccw)
val (vt, vr) = new_e.orbitalVelocityInPoint(currentState.coord)
val r = if (or.ccw) (currentState.coord - planet_coord).n else -(currentState.coord - planet_coord).n
val (vt, vr) = new_e.orbitalVelocityInPoint(currentState.coord, or.ccw)
val r = (currentState.coord - planet_coord).n
val t = r.perpendicular
currentState.vel = vr * r + vt * t + planet_vel
case _ =>
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52 changes: 33 additions & 19 deletions orbitalkiller/src/main/scala/com/github/dunnololda/scageprojects/orbitalkiller/package.scala
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Expand Up @@ -1483,26 +1483,26 @@ package object orbitalkiller {
* Если против часовой стрелки - положительный, от 0 до pi, иначе отрицательный, от 0 до -pi
* https://en.wikipedia.org/wiki/Lambert%27s_problem
* https://en.wikipedia.org/wiki/Kepler_orbit
* @return vr - радиальная компонента, направлена к притягивающему центру
* vt - перпендикулярна радиальной компоненте
* @return vr - радиальная компонента, направлена к притягивающему центру. r = (position_on_orbit - planet.coord).n
* vt - перпендикулярна радиальной компоненте. t = r.perpendicular
* math.sqrt(vr*vr + vt*vt) даст числовое выражение скорости
*/
def orbitalVelocityByTrueAnomalyRad(teta_rad: Double):(Double, Double) = {
def orbitalVelocityByTrueAnomalyRad(teta_rad: Double, ccw:Boolean):(Double, Double) = {
val vr = math.sqrt(mu / p) * e * math.sin(teta_rad)
val vt = math.sqrt(mu / p) * (1 + e * math.cos(teta_rad))
(vt, vr)
if(ccw) (vt, vr) else (-vt, -vr)
}

def orbitalVelocityByDir(dir: DVec):(Double, Double) = {
orbitalVelocityByTrueAnomalyRad(tetaRad2PiByDir(dir))
def orbitalVelocityByDir(dir: DVec, ccw:Boolean):(Double, Double) = {
orbitalVelocityByTrueAnomalyRad(tetaRad2PiByDir(dir), ccw)
}

def orbitalVelocityInPoint(point: DVec):(Double, Double) = {
orbitalVelocityByTrueAnomalyRad(tetaRad2PiInPoint(point))
def orbitalVelocityInPoint(point: DVec, ccw:Boolean):(Double, Double) = {
orbitalVelocityByTrueAnomalyRad(tetaRad2PiInPoint(point), ccw)
}

def orbitalVelocityValueByTrueAnomalyRad(teta_rad: Double):Double = {
val (vt, vr) = orbitalVelocityByTrueAnomalyRad(teta_rad)
val (vt, vr) = orbitalVelocityByTrueAnomalyRad(teta_rad, ccw = true)
math.sqrt(vr * vr + vt * vt)
}

Expand Down Expand Up @@ -1758,11 +1758,11 @@ package object orbitalkiller {
orbitalVelocityValueByTrueAnomalyRad(tetaRad2PiByDir(dir))
}

def orbitalVelocityInPoint(point: DVec):DVec = {
def orbitalVelocityInPoint(point: DVec, ccw:Boolean):DVec = {
val v = orbitalVelocityValueByTrueAnomalyRad(tetaRad2PiInPoint(point))
val r = point.dist(f)
val phi = 3*math.Pi/2 + math.sqrt(a * a * (e * e - 1) / (r * (2 * a + r))).myacos // угол между вектором скорости и радиус-вектором
(point - f).rotateRad(-phi).n*v
if(ccw) (point - f).rotateRad(-phi).n*v else (point - f).rotateRad(phi).n*v
}

// Балк М.Б. Элементы динамики космического полета. Гл. III, параграф 3 "Решение уравнения Кеплера", стр. 111
Expand All @@ -1777,18 +1777,25 @@ package object orbitalkiller {
}
val t1 = tetaDeg360InPoint(point1)
val away_from_rp = teta_deg_min >= t1 && t1 >= 0
val time_from_r_p_to_cur_point_msec = if (away_from_rp) {
travelTimeOnOrbitMsecCCW(0, t1)
} else {
travelTimeOnOrbitMsecCCW(t1, 360)
}
val time_from_r_p_msec = if (away_from_rp) {
val time_from_r_p_to_cur_point_msec = travelTimeOnOrbitMsecCCW(0, t1 /*, print_variant = true*/)
time_from_r_p_to_cur_point_msec + time_msec
} else {
val time_from_cur_point_to_r_p_msec = travelTimeOnOrbitMsecCCW(t1, 360 /*, print_variant = true*/)
(time_msec - time_from_cur_point_to_r_p_msec).abs
(time_msec - time_from_r_p_to_cur_point_msec).abs
}
val M = 1 / inv_n * (0.001*time_from_r_p_msec)
val (resH, iterations) = solver(_arsh((M + M) / e), M)
val tg_half_teta_res_rad = math.sqrt((e + 1) / (e - 1)) * math.tanh(resH / 2)
val teta_res_rad = math.atan(tg_half_teta_res_rad) * 2
val teta_res_deg = teta_res_rad / math.Pi * 180
val teta_res_deg = if(away_from_rp || time_msec >= time_from_r_p_to_cur_point_msec) {
teta_res_rad / math.Pi * 180
} else {
360 - teta_res_rad / math.Pi * 180
}
orbitalPointByTrueAnomalyDeg(teta_res_deg)
}

Expand All @@ -1801,18 +1808,25 @@ package object orbitalkiller {
}
val t1 = tetaDeg360InPoint(point1)
val away_from_rp = 360 >= t1 && t1 >= teta_deg_max
val time_from_r_p_to_cur_point_msec = if(away_from_rp) {
travelTimeOnOrbitMsecCW(360, t1)
} else {
travelTimeOnOrbitMsecCW(t1, 0)
}
val time_from_r_p_msec = if(away_from_rp) {
val time_from_r_p_to_cur_point_msec = travelTimeOnOrbitMsecCW(360, t1 /*, print_variant = true*/)
time_from_r_p_to_cur_point_msec + time_msec
} else {
val time_from_cur_point_to_r_p_msec = travelTimeOnOrbitMsecCW(t1, 0 /*, print_variant = true*/)
(time_msec - time_from_cur_point_to_r_p_msec).abs
(time_msec - time_from_r_p_to_cur_point_msec).abs
}
val M = 1 / inv_n * (0.001*time_from_r_p_msec)
val (resH, iterations) = solver(_arsh((M + M) / e), M)
val tg_half_teta_res_rad = math.sqrt((e + 1) / (e - 1)) * math.tanh(resH / 2)
val teta_res_rad = math.atan(tg_half_teta_res_rad) * 2
val teta_res_deg = 360 - teta_res_rad / math.Pi * 180
val teta_res_deg = if(away_from_rp || time_msec >= time_from_r_p_to_cur_point_msec) {
360 - teta_res_rad / math.Pi * 180
} else {
teta_res_rad / math.Pi * 180
}
orbitalPointByTrueAnomalyDeg(teta_res_deg)
}

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6 changes: 3 additions & 3 deletions ...killer/src/main/scala/com/github/dunnololda/scageprojects/orbitalkiller/ships/Ship4.scala
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Expand Up @@ -728,16 +728,16 @@ class Ship4(index: Int,
or.ellipseOrbit.foreach(e => {
val time_to_stop_msec = (_stop_after_number_of_tacts * base_dt * 1000).toLong
val position_at_stop_moment = e.orbitalPointAfterTime(coord, time_to_stop_msec, or.ccw)
val (vt, vr) = e.orbitalVelocityInPoint(position_at_stop_moment)
val r = if (or.ccw) (position_at_stop_moment - or.planet.coord).n else -(position_at_stop_moment - or.planet.coord).n
val (vt, vr) = e.orbitalVelocityInPoint(position_at_stop_moment, or.ccw)
val r = (position_at_stop_moment - or.planet.coord).n
val t = r.perpendicular
val v = (vt*t + vr*r).n
drawDashedArrow(DVec.zero.actualPosBeforeRotation - v*radius, DVec.zero.actualPosBeforeRotation + v*radius, 1, colorIfPlayerAliveOrRed(CYAN))
})
or.hyperbolaOrbit.foreach(e => {
val time_to_stop_msec = (_stop_after_number_of_tacts * base_dt * 1000).toLong
val position_at_stop_moment = e.orbitalPointAfterTime(coord, time_to_stop_msec, or.ccw)
val v = e.orbitalVelocityInPoint(position_at_stop_moment).n
val v = e.orbitalVelocityInPoint(position_at_stop_moment, or.ccw).n
drawDashedArrow(DVec.zero.actualPosBeforeRotation - v*radius, DVec.zero.actualPosBeforeRotation + v*radius, 1, colorIfPlayerAliveOrRed(CYAN))
})
})
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