FlightGear: JSBSim::FGScript Class Reference

Encapsulates the JSBSim scripting capability. More...

#include <FGScript.h>

Public Member Functions
	FGScript (FGFDMExec *exec)
	Default constructor.

	~FGScript ()
	Default destructor.

bool	LoadScript (const SGPath &script, double default_dT, const SGPath &initfile)
	Loads a script to drive JSBSim (usually in standalone mode).

bool	RunScript (void)
	This function is called each pass through the executive Run() method IF scripting is enabled.

void	ResetEvents (void)

Public Member Functions inherited from JSBSim::FGJSBBase
	FGJSBBase ()
	Constructor for FGJSBBase.

virtual	~FGJSBBase ()
	Destructor for FGJSBBase.

void	PutMessage (const Message &msg)
	Places a Message structure on the Message queue.

void	PutMessage (const std::string &text)
	Creates a message with the given text and places it on the queue.

void	PutMessage (const std::string &text, bool bVal)
	Creates a message with the given text and boolean value and places it on the queue.

void	PutMessage (const std::string &text, int iVal)
	Creates a message with the given text and integer value and places it on the queue.

void	PutMessage (const std::string &text, double dVal)
	Creates a message with the given text and double value and places it on the queue.

int	SomeMessages (void) const
	Reads the message on the queue (but does not delete it).

void	ProcessMessage (void)
	Reads the message on the queue and removes it from the queue.

Message *	ProcessNextMessage (void)
	Reads the next message on the queue and removes it from the queue.

void	disableHighLighting (void)
	Disables highlighting in the console output.

Additional Inherited Members
Public Types inherited from JSBSim::FGJSBBase
enum	{ eL = 1 , eM , eN }
	Moments L, M, N. More...

enum	{ eP = 1 , eQ , eR }
	Rates P, Q, R. More...

enum	{ eU = 1 , eV , eW }
	Velocities U, V, W. More...

enum	{ eX = 1 , eY , eZ }
	Positions X, Y, Z. More...

enum	{ ePhi = 1 , eTht , ePsi }
	Euler angles Phi, Theta, Psi. More...

enum	{ eDrag = 1 , eSide , eLift }
	Stability axis forces, Drag, Side force, Lift. More...

enum	{ eRoll = 1 , ePitch , eYaw }
	Local frame orientation Roll, Pitch, Yaw. More...

enum	{ eNorth = 1 , eEast , eDown }
	Local frame position North, East, Down. More...

enum	{ eLat = 1 , eLong , eRad }
	Locations Radius, Latitude, Longitude. More...

enum	{ inNone = 0 , inDegrees , inRadians , inMeters , inFeet }
	Conversion specifiers. More...

static const std::string &	GetVersion (void)
	Returns the version number of JSBSim.

static constexpr double	KelvinToFahrenheit (double kelvin)
	Converts from degrees Kelvin to degrees Fahrenheit.

static constexpr double	CelsiusToRankine (double celsius)
	Converts from degrees Celsius to degrees Rankine.

static constexpr double	RankineToCelsius (double rankine)
	Converts from degrees Rankine to degrees Celsius.

static constexpr double	KelvinToRankine (double kelvin)
	Converts from degrees Kelvin to degrees Rankine.

static constexpr double	RankineToKelvin (double rankine)
	Converts from degrees Rankine to degrees Kelvin.

static constexpr double	FahrenheitToCelsius (double fahrenheit)
	Converts from degrees Fahrenheit to degrees Celsius.

static constexpr double	CelsiusToFahrenheit (double celsius)
	Converts from degrees Celsius to degrees Fahrenheit.

static constexpr double	CelsiusToKelvin (double celsius)
	Converts from degrees Celsius to degrees Kelvin.

static constexpr double	KelvinToCelsius (double kelvin)
	Converts from degrees Kelvin to degrees Celsius.

static constexpr double	FeetToMeters (double measure)
	Converts from feet to meters.

static double	PitotTotalPressure (double mach, double p)
	Compute the total pressure in front of the Pitot tube.

static double	MachFromImpactPressure (double qc, double p)
	Compute the Mach number from the differential pressure (qc) and the static pressure.

static double	VcalibratedFromMach (double mach, double p)
	Calculate the calibrated airspeed from the Mach number.

static double	MachFromVcalibrated (double vcas, double p)
	Calculate the Mach number from the calibrated airspeed.Based on the formulas in the US Air Force Aircraft Performance Flight Testing Manual (AFFTC-TIH-99-01).

static bool	EqualToRoundoff (double a, double b)
	Finite precision comparison.

static bool	EqualToRoundoff (float a, float b)
	Finite precision comparison.

static bool	EqualToRoundoff (float a, double b)
	Finite precision comparison.

static bool	EqualToRoundoff (double a, float b)
	Finite precision comparison.

static constexpr double	Constrain (double min, double value, double max)
	Constrain a value between a minimum and a maximum value.

static constexpr double	sign (double num)

static double	GaussianRandomNumber (void)

Static Public Attributes inherited from JSBSim::FGJSBBase
static char	highint [5] = {27, '[', '1', 'm', '\0' }
	highlights text

static char	halfint [5] = {27, '[', '2', 'm', '\0' }
	low intensity text

static char	normint [6] = {27, '[', '2', '2', 'm', '\0' }
	normal intensity text

static char	reset [5] = {27, '[', '0', 'm', '\0' }
	resets text properties

static char	underon [5] = {27, '[', '4', 'm', '\0' }
	underlines text

static char	underoff [6] = {27, '[', '2', '4', 'm', '\0' }
	underline off

static char	fgblue [6] = {27, '[', '3', '4', 'm', '\0' }
	blue text

static char	fgcyan [6] = {27, '[', '3', '6', 'm', '\0' }
	cyan text

static char	fgred [6] = {27, '[', '3', '1', 'm', '\0' }
	red text

static char	fggreen [6] = {27, '[', '3', '2', 'm', '\0' }
	green text

static char	fgdef [6] = {27, '[', '3', '9', 'm', '\0' }
	default text

static short	debug_lvl = 1

static std::string	CreateIndexedPropertyName (const std::string &Property, int index)

static Message	localMsg

static std::queue< Message >	Messages

static unsigned int	messageId = 0

static constexpr double	radtodeg = 180. / 3.14159265358979323846

static constexpr double	degtorad = 3.14159265358979323846 / 180.

static constexpr double	hptoftlbssec = 550.0

static constexpr double	psftoinhg = 0.014138

static constexpr double	psftopa = 47.88

static constexpr double	ktstofps = 1.68781

static constexpr double	fpstokts = 1.0 / ktstofps

static constexpr double	inchtoft = 1.0/12.0

static constexpr double	fttom = 0.3048

static constexpr double	m3toft3 = 1.0/(fttomfttomfttom)

static constexpr double	in3tom3 = inchtoftinchtoftinchtoft/m3toft3

static constexpr double	inhgtopa = 3386.38

static constexpr double	slugtolb = 32.174049
	Note that definition of lbtoslug by the inverse of slugtolb and not to a different constant you can also get from some tables will make lbtoslug*slugtolb == 1 up to the magnitude of roundoff.

static constexpr double	lbtoslug = 1.0/slugtolb

static constexpr double	kgtolb = 2.20462

static constexpr double	kgtoslug = 0.06852168

static const std::string	needed_cfg_version = "2.0"

static const std::string	JSBSim_version = JSBSIM_VERSION " " __DATE__ " " __TIME__

static int	gaussian_random_number_phase = 0

Detailed Description

Encapsulates the JSBSim scripting capability.

Scripting support provided via FGScript.

There is support for scripting provided in the FGScript class. Commands are specified using the Scripting Directives for JSBSim. The script file is in XML format. A test condition (or conditions) can be set up in an event in a script and when the condition evaluates to true, the specified action[s] is/are taken. An event can be persistent, meaning that at every time the test condition first evaluates to true (toggling from false to true) then the specified set actions take place. An event can also be defined to execute or evaluate continuously while the condition is true. When the set of tests evaluates to true for a given condition, an item may be set to another value. This value may be a value, or a delta value, and the change from the current value to the new value can be either via a step action, a ramp, or an exponential approach. The speed of a ramp or exponential approach is specified via the time constant. Here is an example illustrating the format of the script file:

<?xml version="1.0"?>
<runscript name="C172-01A takeoff run">
  <!--
    This run is for testing the C172 altitude hold autopilot
  -->
 
  <use aircraft="c172x"/>
  <use initialize="reset00"/>
  <run start="0.0" end="3000" dt="0.0083333">
 
    <event name="engine start">
      <notify/>
      <condition>
        sim-time-sec >= 0.25
      </condition>
      <set name="fcs/throttle-cmd-norm" value="1.0" action="FG_RAMP" tc ="0.5"/>
      <set name="fcs/mixture-cmd-norm" value="0.87" action="FG_RAMP" tc ="0.5"/>
      <set name="propulsion/magneto_cmd" value="3"/>
      <set name="propulsion/starter_cmd" value="1"/>
    </event>
 
    <event name="set heading hold">
      <!-- Set Heading when reach 5 ft -->
      <notify/>
      <condition>
        position/h-agl-ft >= 5
      </condition>
      <set name="ap/heading_setpoint" value="200"/>
      <set name="ap/attitude_hold" value="0"/>
      <set name="ap/heading_hold" value="1"/>
    </event>
 
    <event name="set autopilot">
      <!-- Set Autopilot for 20 ft -->
      <notify/>
      <condition>
        aero/qbar-psf >= 4
      </condition>
      <set name="ap/altitude_setpoint" value="100.0" action="FG_EXP" tc ="2.0"/>
      <set name="ap/altitude_hold" value="1"/>
      <set name="fcs/flap-cmd-norm" value=".33"/>
    </event>
 
    <event name="set autopilot 2" persistent="true">
      <!-- Set Autopilot for 6000 ft -->
      <notify/>
      <condition>
        aero/qbar-psf > 5
      </condition>
      <set name="ap/altitude_setpoint" value="6000.0"/>
    </event>
 
    <event name="Time Notify">
      <notify/>
      <condition> sim-time-sec >= 500 </condition>
    </event>
 
    <event name="Time Notify">
      <notify/>
      <condition> sim-time-sec >= 1000 </condition>
    </event>
 
  </run>
 
</runscript>

The first line must always be present - it identifies the file as an XML format file. The second line identifies this file as a script file, and gives a descriptive name to the script file. Comments are next, delineated by the <!– and –> symbols. The aircraft and initialization files to be used are specified in the "use" lines. Next, comes the "run" section, where the conditions are described in "event" clauses.

Author: Jon S. Berndt

Definition at line 166 of file FGScript.h.

Constructor & Destructor Documentation

◆ FGScript()

JSBSim::FGScript::FGScript ( FGFDMExec * exec )

Default constructor.

Definition at line 64 of file FGScript.cpp.

◆ ~FGScript()

JSBSim::FGScript::~FGScript ( )

Default destructor.

Definition at line 73 of file FGScript.cpp.

Member Function Documentation

◆ LoadScript()

bool JSBSim::FGScript::LoadScript	(	const SGPath &	script,
		double	default_dT,
		const SGPath &	initfile )

Loads a script to drive JSBSim (usually in standalone mode).

The language is the Script Directives for JSBSim. If a simulation step size has been supplied on the command line, it will override the script specified simulation step size.

Parameters

script	the filename (including path name, if any) for the script.
default_dT	the default simulation step size if no value is specified in the script
initfile	An optional initialization file name passed in, empty by default. If a file name is passed in, it will override the one present in the script.

Returns: true if successful

Definition at line 91 of file FGScript.cpp.

◆ ResetEvents()

void JSBSim::FGScript::ResetEvents ( void )

Definition at line 368 of file FGScript.cpp.

◆ RunScript()

bool JSBSim::FGScript::RunScript ( void )

This function is called each pass through the executive Run() method IF scripting is enabled.

Returns: false if script should exit (i.e. if time limits are violated

Definition at line 379 of file FGScript.cpp.

The documentation for this class was generated from the following files:

Public Member Functions

Additional Inherited Members