RTS2 targets used for scheduling are represented by subclass of Target class. If you would like to introduce a new target type, you must:

1. introduce its type identifier among types listed in types table. This table contains character identifiing type and short type description.
2. add its description to src/utils/rts2target.h file. Find defines starting with TYPE_, and add your own type, together with characted which represents it. This define is of course not required, but it is highly recommended.
3. create table which will hold target extended parameters. This table must include reference to tar_id from targets as primary key.
4. create its class as subclass of Target class in src/utils directory. You might choose to create a new file with this subclass, or add its definition to existing file. It is recommended to start a new file. You must add this file to src/utilsdb/Makefile.am - please look at this file for rts2targetgrb string to see where it must be added.
5. in subclass load method, you can add any additional select statements which will load from database additional fields. For an example, look to rts2targetgrb.ec for ::load method implementation. You can of course use any ECPG statements. Please consult ECPG documentation for details.
6. add this target type to Target *createTarget (int _tar_id, struct ln_lnlat_posn *_obs) in src/utilsdb/target.ec.

There is an example. Lets suppose we would like to add target for observing earth low orbit satelites. This target will have seven extra parameters - six for description of the orbit, seventh for date of orbit update. We start with adding type to types table, using pgsql console:

stars=# INSERT INTO types VALUES ('b', 'Earth orbit satelites');
INSERT 0 1
stars=#

Then add type define to sr/utils/rts2target.h:

// master plan target
#define TYPE_PLAN               'p'
 
// target type for
#define TYPE_ORBIT              'b'

Now add table orbits for additional parameters:

stars=# INSERT INTO types VALUES ('b', 'Earth orbit satelites');
INSERT 0 1
stars=#

Then add type define to sr/utils/rts2target.h:

// master plan target
#define TYPE_PLAN               'p'
 
// target type for
#define TYPE_ORBIT              'b'

Now add table orbits for additional parameters:

stars=# CREATE TABLE orbits (tar_id INTEGER REFERENCES targets (tar_id), p1 float8 NOT NULL, p2 float8 NOT NULL, p3 float8 NOT NULL, p4 float8 NOT NULL, p5 float8 NOT NULL, p6 float8 NOT NULL, p7 TIMESTAMP NOT NULL);

Now we will create in src/utilsdb files rts2targetorbit.h and rts2targetorbit.cpp and add them to Makefile.am in this directory:

inst_HEADERS = sqlerror.h rts2devicedb.h target.h rts2appdb.h rts2sqlcolumn.h rts2obs.h rts2obsset.h \
        .....
                        rts2imgsetstat.h rts2targetell.h rts2user.h rts2userset.h account.h accountset.h rts2targetorbit.h
 
EXTRA_DIST = sqlerror.ec rts2devicedb.ec target.ec sub_targets.ec rts2appdb.ec airmasscale.ec rts2sqlcolumn.ec rts2obs.ec \
        .....
                        rts2user.ec rts2userset.ec account.ec accountset.ec rts2targetorbit.ec
 
CLEANFILES = sqlerror.cpp rts2devicedb.cpp target.cpp sub_targets.cpp rts2appdb.cpp airmasscale.cpp rts2sqlcolumn.cpp rts2obs.cpp \
        .....
                        rts2user.cpp rts2userset.cpp account.cpp accountset.cpp rts2targetorbit.cpp
 
nodist_librts2blockdb_a_SOURCES = sqlerror.cpp rts2devicedb.cpp target.cpp sub_targets.cpp rts2appdb.cpp rts2sqlcolumn.cpp rts2obs.cpp \
        .....
                        rts2imgsetstat.cpp rts2targetell.cpp rts2user.cpp rts2userset.cpp account.cpp accountset.cpp rts2targetorbit.cpp

After you are done, you can fill rts2targetorbit.h and rts2targetorbit.cpp file.There is rts2targetorbit.h:

#include "target.h"
 
class Rts2TargetOrbit {
        private:
                double p1;
                double p2;
                double p3;
                double p4;
                double p5;
                double p6;
                time_t p7;
        public:
                Rts2TargetOrbit (int _tar_id, struct ln_lnlat_posn *_obs);
                Rts2TargetOrbit ();
 
                virtual int getRST (struct ln_rts_time *rst, double jd, double horizon);
                virtual int load ();
};

and there is rts2targetorbit.cpp:

#include "rts2targetorbit.h"
 
Rts2TargetOrbit (int _tar_id, struct ln_lnlat_posn *_obs)
:Target (_tar_id, _obs)
{
        p1 = p2 = p3 = p4 = p5 = p6 = nan ("f");
        p7 = 0;
}
 
int
Rts2TargetOrbit::getRST (struct ln_rts_time *rst, double jd, double horizon)
{
 
}
 
int
Rts2TargetOrbit::load ()
{
        EXEC SQL BEGIN DECLARE SECTION;
        double d_p1;
        double d_p2;
        double d_p3;
        double d_p4;
        double d_p5;
        double d_p6;
        int d_p7;
        int d_tar_id = getTargetID ();
        EXEC SQL END DECLARE SECTION;
 
        EXEC SQL SELECT
                p1,
                p2,
                p3,
                p4,
                p5,
                p6,
                EXTRACT (EPOCH FROM p7)
        INTO
                :d_p1,
                :d_p2,
                :d_p3,
                :d_p4,
                :d_p5,
                :d_p6,
                :d_p7
        FROM
                orbits
        WHERE
                tar_id = :d_tar_id;
 
        if (sqlca.sqlcode)
        {
                logMsgDb ("TargetOrbit::load", MESSAGE_ERROR);
                return -1;
        }
        p1 = d_p1;
        p2 = d_p2;
        p3 = d_p3;
        p4 = d_p4;
        p5 = d_p5;
        p6 = d_p6;
        p7 = d_p7;
 
        return Target::load ();
}

And finally add new target type to createTarget method:

Target *createTarget (int _tar_id, struct ln_lnlat_posn *_obs)
{
        EXEC SQL BEGIN DECLARE SECTION;
        int db_tar_id = _tar_id;
        char db_type_id;
        EXEC SQL END DECLARE SECTION;
.....
                case TYPE_PLANET:
                        retTarget = new TargetPlanet (_tar_id, _obs);
                        break;
                case TYPE_ORBIT:
                        retTarget = new Rts2TargetOrbit (_tar_id, _obs);
                default:
                        retTarget = new ConstTarget (_tar_id, _obs);
                        break;
.....
}