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.SH NAME
projection \- Create and manipulate projection objects

.SH SYNOPSIS
\fB projection \fItype\fR ?\fIparameters\fR?
.PP

.SH DESCRIPTION
.PP

This command creates projection object, used to recalculate geographic

coordinates (latitude and longitude) into map projection coodrinates. .PP
\fBprojection\fR command takes list of options and returns name of newly created projection object.

Name of object can be used as Tcl command which have several subcommands

(see \fBPROJECTION SUBCOMMANDS\fR below) used for manipulation of projections.

.SH PROJECTION TYPES

Most important property of projection is projection type. fGIS supports

following types of projections:

\» list should be here

.SH PROJECTION OPTIONS

\» list should be here

.SH PROJECTION SUBCOMMANDS
.TP 8
\fIprojName \fBforward\fI long lat\fR
recieves two arguments - geographic longitude and latitude as degrees in decimal format and returs list of two double values representing map coordinates in meters.

.TP 8
\fIprojName \fBbackward\fI X Y \fR
performs backword transformation - given map coordinates in meters returns longitude and latitude in decimal degrees, .TP 8
\fIprojName \fBformat\fI X Y\fR ?\fB-format\fI formatString\fR

Returns formatted representation of latitude and longitude. String

can contain following escapes sequences:
.RS
.TP
\fB%lt\fR
unsigned latitude in DDMMSS format
.TP
\fB%lg\fR
unsigned longitude in DDMMSS format
.TP
\fB%-t\fR \fB%-g\fR
optionally signed latitude and longitude in DDMMSS format .TP
\fB%+t\fR \fB%+g\fR
explicitely signed latitude and longitude in DDMMSS format .TP
\fB%lG %lT %-G %-T %+G %+T\fR
same as above, but in decimal fractions of degree .TP
\fB%dl %dg\fR
direction indicator - letters N and S for latitude and E and W for longitude (or some other national language values as defined in fgis.rc file).
.RE

If \fIformatString\fR omitted, default «%lt%dt %lg%dg» is used.

.TP 8
\fIprojName\fB dump\fR
returns argumets for projection command used to create this projection object.
.TP 8
\fIprojName\fB delete\fR
destroys projection object.

.SH «SEE ALSO"

.BR proj «(1), « pj_init «(3), « transform (1)


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