fact.features.source

Class SourcePosition

java.lang.Object

fact.features.source.SourcePosition

All Implemented Interfaces:

stream.Processor, stream.StatefulProcessor

public class SourcePosition
extends Object
implements stream.StatefulProcessor

This calculates the position of the source in the camera. The Telescope usually does not look directly at the source but somewhere close by. That means the image of the source projected by the mirrors onto the camera is not exactly in the center but at some point (X,Y). This point will be called source position from now on. The point (0.0, 0.0) is the center of the camera. In order to calculate the source position we need to know where the telescope is looking. And at what time exactly. This data is written by the telescope drive system into auxiliary .fits files called DRIVE_CONTROL_SOURCE_POSITION and DRIVE_CONTROL_TRACKING_POSITION.

This processor handles a handful of different tasks. It can calculate the source position in the camera for some fixed celestial coordinates (e.g. In case you want to get the coordinates of a star projected onto the camera plane)

For data processing we need the auxService to read data from both the DRIVE_CONTROL_SOURCE_POSITION and the DRIVE_CONTROL_TRACKING_POSITION files. The first contains the name and celestial coordinates of the source we're at looking while the second contains information at where the telescope pointing which is updated in small intervals.

Unfortunately MC processed files have to be treated differently than data files since there are no pointing positions written to auxiliary files. For newer ceres versions which allow the simulation of wobble positions (after revision 18159), the source and pointing information are simply taken from the data stream.

For older ceres versions you can simply specify fixed X and Y coordinates in the camera plane.

Author:

Kai Bruegge <kai.bruegge@tu-dortmund.de> , Fabian Temme <fabian.temme@tu-dortmund.de>, Max Nöthe;

Field Summary

Fields

Modifier and Type	Field and Description
AuxiliaryService	auxService
boolean	hasMcWobblePosition
String	outputKey
String	pointingAzKey
String	pointingZdKey
String	sourceAzKey
Double	sourceDeclination
Double	sourceRightAscension
String	sourceZdKey
String	timeStampKey
Double	x
Double	y

Constructor Summary

Constructors

Constructor and Description
SourcePosition()

Method Summary

Modifier and Type	Method and Description
void	finish()
void	init(stream.ProcessContext arg0) Here we check whether an auxservice has been set or some fixed coordinates have been provided in the .xml.
stream.Data	process(stream.Data item) The process method adds the azimuth and zenith values for the pointing, tracking and source position.
void	resetState()

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

outputKey

@Parameter(required=true,
           description="The key to the sourcepos array that will be written to the map.")
public String outputKey

auxService

@Service(required=false,
         description="Name of the service that provides aux files")
public AuxiliaryService auxService

timeStampKey

@Parameter(required=false,
           description="The key containing the event timestamp")
public String timeStampKey

x

@Parameter(description="If set, the fixed x position of the source in mm")
public Double x

y

@Parameter(description="If set, the fixed y position of the source in mm")
public Double y

sourceZdKey

@Parameter(description="In case of MC-Input you specify the key to the source coordinates")
public String sourceZdKey

sourceAzKey

@Parameter(description="In case of MC-Input you specify the key to the source coordinates")
public String sourceAzKey

pointingZdKey

@Parameter(description="In case of MC-Input you specify the key to the pointing coordinates")
public String pointingZdKey

pointingAzKey

@Parameter(description="In case of MC-Input you specify the key to the pointing coordinates")
public String pointingAzKey

sourceRightAscension

@Parameter(required=false)
public Double sourceRightAscension

sourceDeclination

@Parameter(required=false)
public Double sourceDeclination

hasMcWobblePosition

public boolean hasMcWobblePosition

Constructor Detail

SourcePosition

public SourcePosition()

Method Detail

process

public stream.Data process(stream.Data item)

The process method adds the azimuth and zenith values for the pointing, tracking and source position. It also adds an overlay to the item so the position can be displayed in the viewer.

Specified by:

process in interface stream.Processor

init

public void init(stream.ProcessContext arg0)
          throws Exception

Here we check whether an auxservice has been set or some fixed coordinates have been provided in the .xml. If any of the parameters sourceZdKey,sourceAzKey,pointingZdKey,pointingAzKey are set then all need to be set.

Specified by:

init in interface stream.StatefulProcessor

Throws:

Exception

resetState

public void resetState()
                throws Exception

Specified by:

resetState in interface stream.StatefulProcessor

Throws:

Exception

finish

public void finish()
            throws Exception

Specified by:

finish in interface stream.StatefulProcessor

Throws:

Exception