Added spice2xyzv, a tool for generating Celestia xyzv files from a set of SPICE SPK kernels.
Chris Laurel
parent
24967b4eda
commit
dd31bae5d5
|
|
@ -0,0 +1,26 @@
|
|||
StartDate "1997-Oct-15 09:27"
|
||||
EndDate "2004-Jun-20 13:00"
|
||||
Observer "SUN"
|
||||
Target "CASSINI"
|
||||
Frame "eclipJ2000"
|
||||
Tolerance 20
|
||||
MinStep 60
|
||||
MaxStep 432000
|
||||
KernelDirectory "c:/dev/cassini/new"
|
||||
Kernels [
|
||||
"de421.bsp"
|
||||
"000331R_SK_LP0_V1P32.bsp"
|
||||
"000331RB_SK_V1P32_V2P12.bsp"
|
||||
"000331R_SK_V2P12_EP15.bsp"
|
||||
"010420R_SCPSE_EP1_JP83.bsp"
|
||||
"010423_SK_JP67_SP0.bsp"
|
||||
"020425B_SK_SM812_T45.bsp"
|
||||
"030201AP_OPK_SM546_T45.bsp"
|
||||
"040622AP_OPK_04122_08222.bsp"
|
||||
"041001AP_SK_04275_08222.bsp"
|
||||
"041210AP_OPK_04329_08189.bsp"
|
||||
"050720AP_SCPSE_05119_08222.bsp"
|
||||
"060323AP_SCPSE_06082_08222.bsp"
|
||||
"070209AP_SCPSE_06356_08222.bsp"
|
||||
"070918AP_SCPSE_07261_10191.bsp"
|
||||
]
|
||||
|
|
@ -0,0 +1,27 @@
|
|||
StartDate "2004-Jun-20 12:00"
|
||||
EndDate "2010-Jul-10 11:00"
|
||||
Observer "SATURN"
|
||||
Target "CASSINI"
|
||||
Frame "eclipJ2000"
|
||||
Tolerance 20
|
||||
MinStep 60
|
||||
MaxStep 432000
|
||||
KernelDirectory "c:/dev/cassini/new"
|
||||
Kernels [
|
||||
"de421.bsp"
|
||||
"sat252s.bsp"
|
||||
"000331R_SK_LP0_V1P32.bsp"
|
||||
"000331RB_SK_V1P32_V2P12.bsp"
|
||||
"000331R_SK_V2P12_EP15.bsp"
|
||||
"010420R_SCPSE_EP1_JP83.bsp"
|
||||
"010423_SK_JP67_SP0.bsp"
|
||||
"020425B_SK_SM812_T45.bsp"
|
||||
"030201AP_OPK_SM546_T45.bsp"
|
||||
"040622AP_OPK_04122_08222.bsp"
|
||||
"041001AP_SK_04275_08222.bsp"
|
||||
"041210AP_OPK_04329_08189.bsp"
|
||||
"050720AP_SCPSE_05119_08222.bsp"
|
||||
"060323AP_SCPSE_06082_08222.bsp"
|
||||
"070209AP_SCPSE_06356_08222.bsp"
|
||||
"070918AP_SCPSE_07261_10191.bsp"
|
||||
]
|
||||
|
|
@ -0,0 +1,14 @@
|
|||
StartDate "2004-Dec-25 02:01:04.183 TDB"
|
||||
EndDate "2005-Jan-14 09:07:00.000 TDB"
|
||||
Observer "SATURN"
|
||||
Target "CASP"
|
||||
Frame "eclipJ2000"
|
||||
Tolerance 0.1
|
||||
MinStep 60
|
||||
MaxStep 86400
|
||||
KernelDirectory "c:/dev/cassini/new"
|
||||
Kernels [
|
||||
"de421.bsp"
|
||||
"sat252s.bsp"
|
||||
"041210AP_OPK_04329_08189.bsp"
|
||||
]
|
||||
|
|
@ -0,0 +1,11 @@
|
|||
# Visual C++ makefile for spice2xyzv.exe
|
||||
|
||||
TARGET=spice2xyzv.exe
|
||||
|
||||
SPICE_INSTALL=c:\dev\spice\cspice
|
||||
|
||||
SOURCE_FILES=\
|
||||
spice2xyzv.cpp
|
||||
|
||||
$(TARGET): $(SOURCE_FILES)
|
||||
cl /EHsc /Ox /MT $(SOURCE_FILES) /Fe$(TARGET) /I $(SPICE_INSTALL)\include $(SPICE_INSTALL)\lib\cspice.lib
|
||||
|
|
@ -0,0 +1,136 @@
|
|||
KPL/LSK
|
||||
|
||||
|
||||
LEAPSECONDS KERNEL FILE
|
||||
===========================================================================
|
||||
|
||||
Modifications:
|
||||
--------------
|
||||
|
||||
2005, Aug. 3 NJB Modified file to account for the leapsecond that
|
||||
will occur on December 31, 2005.
|
||||
|
||||
1998, Jul 17 WLT Modified file to account for the leapsecond that
|
||||
will occur on December 31, 1998.
|
||||
|
||||
1997, Feb 22 WLT Modified file to account for the leapsecond that
|
||||
will occur on June 30, 1997.
|
||||
|
||||
1995, Dec 14 KSZ Corrected date of last leapsecond from 1-1-95
|
||||
to 1-1-96.
|
||||
|
||||
1995, Oct 25 WLT Modified file to account for the leapsecond that
|
||||
will occur on Dec 31, 1995.
|
||||
|
||||
1994, Jun 16 WLT Modified file to account for the leapsecond on
|
||||
June 30, 1994.
|
||||
|
||||
1993, Feb. 22 CHA Modified file to account for the leapsecond on
|
||||
June 30, 1993.
|
||||
|
||||
1992, Mar. 6 HAN Modified file to account for the leapsecond on
|
||||
June 30, 1992.
|
||||
|
||||
1990, Oct. 8 HAN Modified file to account for the leapsecond on
|
||||
Dec. 31, 1990.
|
||||
|
||||
|
||||
Explanation:
|
||||
------------
|
||||
|
||||
The contents of this file are used by the routine DELTET to compute the
|
||||
time difference
|
||||
|
||||
[1] DELTA_ET = ET - UTC
|
||||
|
||||
the increment to be applied to UTC to give ET.
|
||||
|
||||
The difference between UTC and TAI,
|
||||
|
||||
[2] DELTA_AT = TAI - UTC
|
||||
|
||||
is always an integral number of seconds. The value of DELTA_AT was 10
|
||||
seconds in January 1972, and increases by one each time a leap second
|
||||
is declared. Combining [1] and [2] gives
|
||||
|
||||
[3] DELTA_ET = ET - (TAI - DELTA_AT)
|
||||
|
||||
= (ET - TAI) + DELTA_AT
|
||||
|
||||
The difference (ET - TAI) is periodic, and is given by
|
||||
|
||||
[4] ET - TAI = DELTA_T_A + K sin E
|
||||
|
||||
where DELTA_T_A and K are constant, and E is the eccentric anomaly of the
|
||||
heliocentric orbit of the Earth-Moon barycenter. Equation [4], which ignores
|
||||
small-period fluctuations, is accurate to about 0.000030 seconds.
|
||||
|
||||
The eccentric anomaly E is given by
|
||||
|
||||
[5] E = M + EB sin M
|
||||
|
||||
where M is the mean anomaly, which in turn is given by
|
||||
|
||||
[6] M = M + M t
|
||||
0 1
|
||||
|
||||
where t is the number of ephemeris seconds past J2000.
|
||||
|
||||
Thus, in order to compute DELTA_ET, the following items are necessary.
|
||||
|
||||
DELTA_TA
|
||||
K
|
||||
EB
|
||||
M0
|
||||
M1
|
||||
DELTA_AT after each leap second.
|
||||
|
||||
The numbers, and the formulation, are taken from the following sources.
|
||||
|
||||
1) Moyer, T.D., Transformation from Proper Time on Earth to
|
||||
Coordinate Time in Solar System Barycentric Space-Time Frame
|
||||
of Reference, Parts 1 and 2, Celestial Mechanics 23 (1981),
|
||||
33-56 and 57-68.
|
||||
|
||||
2) Moyer, T.D., Effects of Conversion to the J2000 Astronomical
|
||||
Reference System on Algorithms for Computing Time Differences
|
||||
and Clock Rates, JPL IOM 314.5--942, 1 October 1985.
|
||||
|
||||
The variable names used above are consistent with those used in the
|
||||
Astronomical Almanac.
|
||||
|
||||
\begindata
|
||||
|
||||
DELTET/DELTA_T_A = 32.184
|
||||
DELTET/K = 1.657D-3
|
||||
DELTET/EB = 1.671D-2
|
||||
DELTET/M = ( 6.239996D0 1.99096871D-7 )
|
||||
|
||||
DELTET/DELTA_AT = ( 10, @1972-JAN-1
|
||||
11, @1972-JUL-1
|
||||
12, @1973-JAN-1
|
||||
13, @1974-JAN-1
|
||||
14, @1975-JAN-1
|
||||
15, @1976-JAN-1
|
||||
16, @1977-JAN-1
|
||||
17, @1978-JAN-1
|
||||
18, @1979-JAN-1
|
||||
19, @1980-JAN-1
|
||||
20, @1981-JUL-1
|
||||
21, @1982-JUL-1
|
||||
22, @1983-JUL-1
|
||||
23, @1985-JUL-1
|
||||
24, @1988-JAN-1
|
||||
25, @1990-JAN-1
|
||||
26, @1991-JAN-1
|
||||
27, @1992-JUL-1
|
||||
28, @1993-JUL-1
|
||||
29, @1994-JUL-1
|
||||
30, @1996-JAN-1
|
||||
31, @1997-JUL-1
|
||||
32, @1999-JAN-1
|
||||
33, @2006-JAN-1 )
|
||||
|
||||
|
||||
\begintext
|
||||
|
||||
|
|
@ -0,0 +1,129 @@
|
|||
spice2xyzv
|
||||
|
||||
Author: Chris Laurel (claurel@gmail.com)
|
||||
|
||||
|
||||
Spice2xyzv is a command line tool that is used to produce Celestia xyzv files
|
||||
from a set of SPICE SPK kernels. An xyzv file is simply an ASCII file with
|
||||
position and velocity states at unequal time steps. Each record in the file
|
||||
consists of seven double precision values, arranged as such:
|
||||
|
||||
<Julian date (TDB)> <x> <y> <z> <vx> <vy> <vz>
|
||||
|
||||
X, y, and z are components of the position vector; vx, vy, and vz are the
|
||||
velocity vector components.
|
||||
|
||||
|
||||
Why?
|
||||
----
|
||||
|
||||
Celestia supports using SPICE SPK kernels directly, and when high accuracy is
|
||||
required SPICE kernels are the preferred ephemeris source. But the large
|
||||
amount of data required to represent an entire mission with SPK kernels can
|
||||
make this approach less attractive. This is the case for the spacecraft
|
||||
trajectories in the default Celestia package. Spice2xyzv offers a tolerance
|
||||
parameter that lets you pick the optimal balance between size and accuracy for
|
||||
the situation. Spice2xyzv can thus be thought of as a sort of lossy
|
||||
compression tool for SPK files.
|
||||
|
||||
|
||||
Usage
|
||||
-----
|
||||
|
||||
The spice2xyzv command line is extremely simple:
|
||||
|
||||
spice2xyzv <config file>
|
||||
|
||||
The xyzv file is written to standard output, thus you'll generally use the
|
||||
tool with output redirection, e.g:
|
||||
|
||||
spice2xyzv cassini-cruise.cfg > cruise.xyzv
|
||||
|
||||
The configuration file is a text file with a list of named parameters. These
|
||||
parameters have either string, numeric, or string list values. Some of the
|
||||
parameters have defaults and can be omitted from the file. The order in which
|
||||
the parameters appear is not important. The following example is used to
|
||||
produce an xyzv file for the Huygens probe:
|
||||
|
||||
|
||||
StartDate "2004-Dec-25 02:01:04.183 TDB"
|
||||
EndDate "2005-Jan-14 09:07:00.000 TDB"
|
||||
Observer "SATURN"
|
||||
Target "CASP"
|
||||
Frame "eclipJ2000"
|
||||
Tolerance 0.1
|
||||
MinStep 60
|
||||
MaxStep 86400
|
||||
KernelDirectory "c:/dev/cassini/new"
|
||||
Kernels [
|
||||
"de421.bsp"
|
||||
"sat252s.bsp"
|
||||
"041210AP_OPK_04329_08189.bsp"
|
||||
]
|
||||
|
||||
|
||||
Configuration Parameters
|
||||
------------------------
|
||||
|
||||
StartDate and EndDate (string)
|
||||
These parameters specify the time range for the xyzv file. The set of SPK
|
||||
kernels used must provide coverage for the target object (and any necessary
|
||||
frame centers) for any time between start and end. The date strings are
|
||||
parsed by SPICE, which accepts a wide range of different formats. By default,
|
||||
all times are UTC, but the TDB or TDT suffix can be appended (as in the
|
||||
example) to specify a different time system.
|
||||
|
||||
Observer (string)
|
||||
The name or NAIF integer ID of the coordinate center. The choice of
|
||||
coordinate center depends on how the resulting xyzv file will be used: it
|
||||
must match the frame center chosen for the SSC file.
|
||||
|
||||
Target (string)
|
||||
The name or NAIF integer ID of the object that you're generating a trajectory
|
||||
for.
|
||||
|
||||
Frame (string)
|
||||
The name of the reference frame for the xyzv coordinates. Two common frames
|
||||
are:
|
||||
"J2000" - Earth mean equator and equinox of J2000
|
||||
"eclipJ2000" - Earth ecliptic and equinox of J2000
|
||||
If the frame is not one of SPICE's built-in frames, it is necessary to
|
||||
add a frame kernel to the Kernels list in the configuration file.
|
||||
|
||||
Tolerance (number)
|
||||
Maximum permitted error in units of kilometers. Making this value smaller will
|
||||
result in a larger xyzv file.
|
||||
|
||||
MinStep and MaxStep (number)
|
||||
The minimum and maximum time interval (in seconds) between states. The
|
||||
default values are 60 for MinStep and 432000 (5 days) for MaxStep.
|
||||
|
||||
KernelDirectory (string)
|
||||
Directory containing the SPICE kernel files. The default value is ".",
|
||||
indicating that the kernel files reside in the current directory.
|
||||
|
||||
Kernels (string list)
|
||||
List of kernel files that need to be loaded to generate the xyzv file. This
|
||||
list may include more than just SPK files. For instance, a frame kernel file
|
||||
may be necessary to get the position of an object in the desired frame.
|
||||
|
||||
|
||||
|
||||
Method
|
||||
------
|
||||
|
||||
Spice2xyzv uses a very simple method to choose sample times for xyzv states.
|
||||
It calls SPICE to generate a state at a base time t0. It then generates two
|
||||
more states: one at t0+dt/2 and one at t0+dt. Next, the position at t0+dt/2
|
||||
is compared to the result of cubic Hermite interpolation of the SPICE
|
||||
computed positions at t0 and t0+dt. If the distance is within the tolerance
|
||||
specified in the configuration file, the test is repeated with dt*2. This
|
||||
continues until either MaxStep is reached or the interpolated and SPICE
|
||||
calculated positions are further than Tolerance kilometers apart. The last
|
||||
value of dt for which the interpolated position was close enough the the
|
||||
SPICE calculated position is used as the time step, t0 is incremented by
|
||||
dt, and the process is repeated over the entire time span. This adaptive
|
||||
sampling results in a low number of samples in slowly varying parts of the
|
||||
trajectory and more samples at times when the trajectory changes more
|
||||
dramatically.
|
||||
|
||||
|
|
@ -0,0 +1,472 @@
|
|||
// spice2xyzv.cpp
|
||||
//
|
||||
// Copyright (C) 2008, Chris Laurel <claurel@shatters.net>
|
||||
//
|
||||
// This program is free software; you can redistribute it and/or
|
||||
// modify it under the terms of the GNU General Public License
|
||||
// as published by the Free Software Foundation; either version 2
|
||||
// of the License, or (at your option) any later version.
|
||||
//
|
||||
// Create a Celestia xyzv file from a pool of SPICE SPK files
|
||||
|
||||
#include "SpiceUsr.h"
|
||||
#include <string>
|
||||
#include <vector>
|
||||
#include <iostream>
|
||||
#include <fstream>
|
||||
#include <iomanip>
|
||||
#include <cmath>
|
||||
|
||||
using namespace std;
|
||||
|
||||
|
||||
const double J2000 = 2451545.0;
|
||||
|
||||
|
||||
// Default values
|
||||
// Units are seconds
|
||||
const double MIN_STEP_SIZE = 60.0;
|
||||
const double MAX_STEP_SIZE = 5 * 86400.0;
|
||||
|
||||
// Units are kilometers
|
||||
const double TOLERANCE = 20.0;
|
||||
|
||||
|
||||
class Configuration
|
||||
{
|
||||
public:
|
||||
Configuration() :
|
||||
kernelDirectory("."),
|
||||
frameName("eclipJ2000"),
|
||||
minStepSize(MIN_STEP_SIZE),
|
||||
maxStepSize(MAX_STEP_SIZE),
|
||||
tolerance(TOLERANCE)
|
||||
{
|
||||
}
|
||||
|
||||
string kernelDirectory;
|
||||
vector<string> kernelList;
|
||||
string startDate;
|
||||
string endDate;
|
||||
string observerName;
|
||||
string targetName;
|
||||
string frameName;
|
||||
double minStepSize;
|
||||
double maxStepSize;
|
||||
double tolerance;
|
||||
};
|
||||
|
||||
|
||||
// Very basic 3-vector class
|
||||
class Vec3d
|
||||
{
|
||||
public:
|
||||
Vec3d() : x(0.0), y(0.0), z(0.0) {}
|
||||
Vec3d(double _x, double _y, double _z) : x(_x), y(_y), z(_z) {}
|
||||
Vec3d(const double v[]) : x(v[0]), y(v[1]), z(v[2]) {}
|
||||
|
||||
double length() const { return std::sqrt(x * x + y * y + z * z); }
|
||||
|
||||
double x, y, z;
|
||||
};
|
||||
|
||||
// Vector add
|
||||
Vec3d operator+(const Vec3d& v0, const Vec3d& v1)
|
||||
{
|
||||
return Vec3d(v0.x + v1.x, v0.y + v1.y, v0.z + v1.z);
|
||||
}
|
||||
|
||||
// Vector subtract
|
||||
Vec3d operator-(const Vec3d& v0, const Vec3d& v1)
|
||||
{
|
||||
return Vec3d(v0.x - v1.x, v0.y - v1.y, v0.z - v1.z);
|
||||
}
|
||||
|
||||
// Additive inverse
|
||||
Vec3d operator-(const Vec3d& v)
|
||||
{
|
||||
return Vec3d(-v.x, -v.y, -v.z);
|
||||
}
|
||||
|
||||
// Scalar multiply
|
||||
Vec3d operator*(const Vec3d& v, double d)
|
||||
{
|
||||
return Vec3d(v.x * d, v.y * d, v.z * d);
|
||||
}
|
||||
|
||||
// Scalar multiply
|
||||
Vec3d operator*(double d, const Vec3d& v)
|
||||
{
|
||||
return Vec3d(v.x * d, v.y * d, v.z * d);
|
||||
}
|
||||
|
||||
ostream& operator<<(ostream& o, const Vec3d& v)
|
||||
{
|
||||
return o << v.x << ' ' << v.y << ' ' << v.z;
|
||||
}
|
||||
|
||||
|
||||
// The StateVector object just contains the position and velocity
|
||||
// in 3D.
|
||||
class StateVector
|
||||
{
|
||||
public:
|
||||
// Construct a new StateVector from an array of 6 doubles
|
||||
// (as used by SPICE.)
|
||||
StateVector(const double v[]) :
|
||||
position(v), velocity(v + 3) {};
|
||||
|
||||
Vec3d position;
|
||||
Vec3d velocity;
|
||||
};
|
||||
|
||||
|
||||
// QuotedString is used read a double quoted string from a C++ input
|
||||
// stream.
|
||||
class QuotedString
|
||||
{
|
||||
public:
|
||||
string value;
|
||||
};
|
||||
|
||||
istream& operator>>(istream& in, QuotedString& qs)
|
||||
{
|
||||
char c = '\0';
|
||||
|
||||
in >> c;
|
||||
while (in && isspace(c))
|
||||
{
|
||||
in >> c;
|
||||
}
|
||||
|
||||
if (c != '"')
|
||||
{
|
||||
in.setstate(ios::failbit);
|
||||
return in;
|
||||
}
|
||||
|
||||
string s;
|
||||
|
||||
in >> c;
|
||||
while (in && c != '"')
|
||||
{
|
||||
s += c;
|
||||
in.get(c);
|
||||
}
|
||||
|
||||
if (in)
|
||||
qs.value = s;
|
||||
|
||||
return in;
|
||||
}
|
||||
|
||||
|
||||
|
||||
// QuoteStringList is used to read a list of double quoted strings from
|
||||
// a C++ input stream. The string list must be enclosed by square brackets.
|
||||
class QuotedStringList
|
||||
{
|
||||
public:
|
||||
vector<string> value;
|
||||
};
|
||||
|
||||
istream& operator>>(istream& in, QuotedStringList& qsl)
|
||||
{
|
||||
qsl.value.clear();
|
||||
char c = '\0';
|
||||
|
||||
in >> c;
|
||||
if (c != '[')
|
||||
{
|
||||
in.setstate(ios::failbit);
|
||||
return in;
|
||||
}
|
||||
|
||||
in >> c;
|
||||
while (in && c == '"')
|
||||
{
|
||||
in.unget();
|
||||
|
||||
QuotedString qs;
|
||||
if (in >> qs)
|
||||
{
|
||||
qsl.value.push_back(qs.value);
|
||||
in >> c;
|
||||
}
|
||||
}
|
||||
|
||||
if (c != ']')
|
||||
in.setstate(ios::failbit);
|
||||
|
||||
return in;
|
||||
}
|
||||
|
||||
|
||||
|
||||
static Vec3d cubicInterpolate(const Vec3d& p0, const Vec3d& v0,
|
||||
const Vec3d& p1, const Vec3d& v1,
|
||||
double t)
|
||||
{
|
||||
return p0 + (((2.0 * (p0 - p1) + v1 + v0) * (t * t * t)) +
|
||||
((3.0 * (p1 - p0) - 2.0 * v0 - v1) * (t * t)) +
|
||||
(v0 * t));
|
||||
}
|
||||
|
||||
|
||||
double et2jd(double et)
|
||||
{
|
||||
return J2000 + et / 86400.0;
|
||||
}
|
||||
|
||||
|
||||
string etToString(double et)
|
||||
{
|
||||
char buf[200];
|
||||
et2utc_c(et, "C", 3, sizeof(buf), buf);
|
||||
return string(buf);
|
||||
}
|
||||
|
||||
|
||||
void printRecord(ostream& out, double et, const StateVector& state)
|
||||
{
|
||||
// < 1 second error around J2000
|
||||
out << setprecision(12) << et2jd(et) << " ";
|
||||
|
||||
// < 1 meter error at 1 billion km
|
||||
out << setprecision(12) << state.position << " ";
|
||||
|
||||
// < 0.1 mm/s error at 10 km/s
|
||||
out << setprecision(8) << state.velocity << endl;
|
||||
}
|
||||
|
||||
|
||||
StateVector getStateVector(SpiceInt targetID,
|
||||
double et,
|
||||
const string& frameName,
|
||||
SpiceInt observerID)
|
||||
{
|
||||
double stateVector[6];
|
||||
double lightTime = 0.0;
|
||||
|
||||
spkgeo_c(targetID, et, frameName.c_str(), observerID,
|
||||
stateVector, &lightTime);
|
||||
|
||||
return StateVector(stateVector);
|
||||
}
|
||||
|
||||
|
||||
|
||||
bool convertSpkToXyzv(const Configuration& config,
|
||||
ostream& out)
|
||||
{
|
||||
// Load the required SPICE kernels
|
||||
for (vector<string>::const_iterator iter = config.kernelList.begin();
|
||||
iter != config.kernelList.end(); iter++)
|
||||
{
|
||||
string pathname = config.kernelDirectory + "/" + *iter;
|
||||
furnsh_c(pathname.c_str());
|
||||
}
|
||||
|
||||
|
||||
double startET = 0.0;
|
||||
double endET = 0.0;
|
||||
|
||||
str2et_c(config.startDate.c_str(), &startET);
|
||||
str2et_c(config.endDate.c_str(), &endET);
|
||||
|
||||
SpiceBoolean found = SPICEFALSE;
|
||||
SpiceInt observerID = 0;
|
||||
SpiceInt targetID = 0;
|
||||
bodn2c_c(config.observerName.c_str(), &observerID, &found);
|
||||
if (!found)
|
||||
{
|
||||
cerr << "Observer object " << config.observerName << " not found. Aborting.\n";
|
||||
return false;
|
||||
}
|
||||
|
||||
bodn2c_c(config.targetName.c_str(), &targetID, &found);
|
||||
if (!found)
|
||||
{
|
||||
cerr << "Target object " << config.targetName << " not found. Aborting.\n";
|
||||
return false;
|
||||
}
|
||||
|
||||
StateVector lastState = getStateVector(targetID, startET, config.frameName, observerID);
|
||||
double et = startET;
|
||||
|
||||
printRecord(out, et, lastState);
|
||||
|
||||
while (et + config.minStepSize < endET)
|
||||
{
|
||||
double dt = config.minStepSize;
|
||||
|
||||
StateVector s0 = getStateVector(targetID, et + dt, config.frameName, observerID);
|
||||
double et0 = et + dt;
|
||||
|
||||
while (dt < config.maxStepSize && et + dt * 2.0 < endET)
|
||||
{
|
||||
dt *= 2.0;
|
||||
StateVector s1 = getStateVector(targetID, et + dt, config.frameName, observerID);
|
||||
double et1 = et + dt;
|
||||
|
||||
Vec3d pInterp = cubicInterpolate(lastState.position,
|
||||
lastState.velocity * dt,
|
||||
s1.position,
|
||||
s1.velocity * dt,
|
||||
0.5);
|
||||
|
||||
double positionError = (pInterp - s0.position).length();
|
||||
if (positionError > config.tolerance || dt > config.maxStepSize)
|
||||
break;
|
||||
|
||||
s0 = s1;
|
||||
et0 = et1;
|
||||
}
|
||||
|
||||
lastState = s0;
|
||||
et = et0;
|
||||
|
||||
printRecord(out, et0, lastState);
|
||||
}
|
||||
|
||||
lastState = getStateVector(targetID, endET, config.frameName, observerID);
|
||||
printRecord(out, endET, lastState);
|
||||
|
||||
return true;
|
||||
}
|
||||
|
||||
|
||||
bool readConfig(istream& in, Configuration& config)
|
||||
{
|
||||
QuotedString qs;
|
||||
|
||||
while (in && !in.eof())
|
||||
{
|
||||
string key;
|
||||
|
||||
in >> key;
|
||||
if (in.eof())
|
||||
return true;
|
||||
|
||||
if (!in.eof())
|
||||
{
|
||||
if (key == "StartDate")
|
||||
{
|
||||
if (in >> qs)
|
||||
config.startDate = qs.value;
|
||||
}
|
||||
else if (key == "EndDate")
|
||||
{
|
||||
if (in >> qs)
|
||||
config.endDate = qs.value;
|
||||
}
|
||||
else if (key == "Observer")
|
||||
{
|
||||
if (in >> qs)
|
||||
config.observerName = qs.value;
|
||||
}
|
||||
else if (key == "Target")
|
||||
{
|
||||
if (in >> qs)
|
||||
config.targetName = qs.value;
|
||||
}
|
||||
else if (key == "Frame")
|
||||
{
|
||||
if (in >> qs)
|
||||
config.frameName = qs.value;
|
||||
}
|
||||
else if (key == "MinStep")
|
||||
{
|
||||
in >> config.minStepSize;
|
||||
}
|
||||
else if (key == "MaxStep")
|
||||
{
|
||||
in >> config.maxStepSize;
|
||||
}
|
||||
else if (key == "Tolerance")
|
||||
{
|
||||
in >> config.tolerance;
|
||||
}
|
||||
else if (key == "KernelDirectory")
|
||||
{
|
||||
if (in >> qs)
|
||||
config.kernelDirectory = qs.value;
|
||||
}
|
||||
else if (key == "Kernels")
|
||||
{
|
||||
QuotedStringList qsl;
|
||||
if (in >> qsl)
|
||||
{
|
||||
config.kernelList = qsl.value;
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
return in.good();
|
||||
}
|
||||
|
||||
|
||||
int main(int argc, char* argv[])
|
||||
{
|
||||
// Load the leap second kernel
|
||||
furnsh_c("naif0008.tls");
|
||||
|
||||
if (argc < 2)
|
||||
{
|
||||
cerr << "Usage: spice2xyzv <config filename> [output filename]\n";
|
||||
return 1;
|
||||
}
|
||||
|
||||
|
||||
ifstream configFile(argv[1]);
|
||||
if (!configFile)
|
||||
{
|
||||
cerr << "Error opening configuration file.\n";
|
||||
return 1;
|
||||
}
|
||||
|
||||
|
||||
Configuration config;
|
||||
if (!readConfig(configFile, config))
|
||||
{
|
||||
cerr << "Error in configuration file.\n";
|
||||
return 1;
|
||||
}
|
||||
|
||||
|
||||
// Check that all required parameters are present.
|
||||
if (config.startDate.empty())
|
||||
{
|
||||
cerr << "StartDate missing from configuration file.\n";
|
||||
return 1;
|
||||
}
|
||||
|
||||
if (config.endDate.empty())
|
||||
{
|
||||
cerr << "EndDate missing from configuration file.\n";
|
||||
return 1;
|
||||
}
|
||||
|
||||
if (config.targetName.empty())
|
||||
{
|
||||
cerr << "Target missing from configuration file.\n";
|
||||
return 1;
|
||||
}
|
||||
|
||||
if (config.observerName.empty())
|
||||
{
|
||||
cerr << "Observer missing from configuration file.\n";
|
||||
return 1;
|
||||
}
|
||||
|
||||
if (config.kernelList.empty())
|
||||
{
|
||||
cerr << "Kernels missing from configuration file.\n";
|
||||
return 1;
|
||||
}
|
||||
|
||||
convertSpkToXyzv(config, cout);
|
||||
|
||||
return 0;
|
||||
}
|
||||
Loading…
Reference in New Issue