Parent Topic: <A href="http://www.pcigeomatics.com/cgi-bin/pcihlp/PROJ">PROJ</a><hr>
<H3>USER PROJECTIONS</H3>
A set of parameters can be specified for projections supported as 
``Generic'' and accessed by using the unique user-defined name for 
that projection set.  The user-defined projections are presented under
the ``User Projections'' tab in the Works ``Other Georeference Units''
panel.  By accepting a user projection, the supported projection
and the associated parameters are recognized.  The parameters for the
projection may then be reviewed by pressing the ``More...'' button
after accepting the User Projection that has been selected.<p>
The user-defined projections are stored in a text file named
userproj.txt that may exist either locally or in the $PCIHOME/etc
subdirectory or both.  New user projections may be brought into the
system by editing userproj.txt file with a text-editor and adding
the parameters for the projection.  (A template of the fields
supported is included in the userproj.txt file that exists in the
etc sub-directory in the comment lines at the top of the file.)<p>
In general, the following rules should be followed:
<P>
<UL>
<LI> Each non-comment line will consist of a field identifier
(e.g. ProjectionName) and a value for the field (e.g. &quot;UKNatGrid&quot;).
There would be one or more spaces separating the field identifier
and the field value.  The field identifier and value must fit on
one line.  Although the present user projection examples have
the field identifier first followed by the field value, the field
value followed by the field identifier is also supported.
</UL>
<UL>
<LI> Processing for the field identifiers is NOT case-sensitive, so
it doesn't matter if upper or lower case or some combination
of the two is used.
</UL>
<UL>
<LI> Blank lines are acceptable in the file and will be skipped.
</UL>
<UL>
<LI> If a field value has spaces in it, it should be enclosed in
double-quotes.  For example,
</UL>
<PRE>
      ProjectionDescription &quot;British National Grid&quot;
</PRE>
<UL>
<LI> Comments are everything that follow an exclamation mark.
If the line begins with an exclamation mark the whole line
is a comment.  Trailing comments in a given line are acceptable.
</UL>
<UL>
<LI> Processing for a given projection begins when a &quot;ProjectionName&quot;
record is read and ends with the next &quot;ProjectionName&quot; record
or when the end of the file is reached.  Other than that the order
of the other records for the projection does not matter.
</UL>
Different projections require different parameters.  (See the help
topic for a given projection in the PROJECTIONS topic, for what
fields are required for each projection.)  In general, the following
fields can be defined for any user-defined projection set:
<P>
<UL>
<LI> 1) ProjectionName.  This is the user-defined name that will be
presented for the projection set.  This can be 11 printable
characters at most.  For example,
</UL>
<PRE>
       ProjectionName &quot;UKNatGrid&quot;
</PRE>
<UL>
<LI> 2) ProjectionDescription.  This is the descriptive text to present
with the ProjectionName.  Although there is no maximum size,
the ProjectionDescription should be short and no more than
64 characters.  If there are spaces in the description, it
should be enclosed in double-quotes.  For example,
</UL>
<PRE>
       ProjectionDescription &quot;British National Grid&quot;
</PRE>
<UL>
<LI> 3) MapUnits.  These are the actual units of the projection set
and would correspond to the units string built up by using
the &quot;Generic Projections&quot;.  This can be 16 characters at most.
For example, either one of the two examples are acceptable,
</UL>
<PRE>
       MapUnits &quot;tm e9&quot;

       MapUnits &quot;TM          E009&quot;
</PRE>
<hr>
Parent Topic: <A href="http://www.pcigeomatics.com/cgi-bin/pcihlp/PROJ">PROJ</a><br>
<a href="http://www.pcigeomatics.com/dev_corner/pcihlp_gateway.html">About PCI Help Gateway</a>