<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2 Final//EN"> <!--Converted with LaTeX2HTML 2002-2-1 (1.71) original version by: Nikos Drakos, CBLU, University of Leeds * revised and updated by: Marcus Hennecke, Ross Moore, Herb Swan * with significant contributions from: Jens Lippmann, Marek Rouchal, Martin Wilck and others --> <HTML> <HEAD> <TITLE>1.4.5 Orthographic projection</TITLE> <META NAME="description" CONTENT="1.4.5 Orthographic projection"> <META NAME="keywords" CONTENT="GMT_Tutorial"> <META NAME="resource-type" CONTENT="document"> <META NAME="distribution" CONTENT="global"> <META NAME="Generator" CONTENT="LaTeX2HTML v2002-2-1"> <META HTTP-EQUIV="Content-Style-Type" CONTENT="text/css"> <LINK REL="STYLESHEET" HREF="GMT_Tutorial.css"> <LINK REL="next" HREF="node31.html"> <LINK REL="previous" HREF="node27.html"> <LINK REL="up" HREF="node20.html"> <LINK REL="next" HREF="node30.html"> </HEAD> <BODY bgcolor="#ffffff"> <!--Navigation Panel--> <A NAME="tex2html813" HREF="node30.html"> <IMG WIDTH="37" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="next" SRC="next.png"></A> <A NAME="tex2html807" HREF="node20.html"> <IMG WIDTH="26" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="up" SRC="up.png"></A> <A NAME="tex2html801" HREF="node28.html"> <IMG WIDTH="63" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="previous" SRC="prev.png"></A> <A NAME="tex2html809" HREF="node1.html"> <IMG WIDTH="65" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="contents" SRC="contents.png"></A> <A NAME="tex2html811" HREF="node63.html"> <IMG WIDTH="43" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="index" SRC="index.png"></A> <BR> <B> Next:</B> <A NAME="tex2html814" HREF="node30.html">1.4.5.1 Exercises</A> <B> Up:</B> <A NAME="tex2html808" HREF="node20.html">1.4 Laboratory Exercises</A> <B> Previous:</B> <A NAME="tex2html802" HREF="node28.html">1.4.4.1 Exercises</A> <B> <A NAME="tex2html810" HREF="node1.html">Contents</A></B> <B> <A NAME="tex2html812" HREF="node63.html">Index</A></B> <BR> <BR> <!--End of Navigation Panel--> <H2><A NAME="SECTION00345000000000000000"> 1.4.5 Orthographic projection</A> </H2> <A NAME="1559"></A> <A NAME="590"></A> <P> The azimuthal orthographic projection (<B>-JG</B>) is one of several projections with similar syntax and behavior; the one we have chosen mimics viewing the Earth from space at an infinite distance; it is neither conformal nor equal-area. The syntax for this projection is <BR> <P> <B>-JG</B><!-- MATH $lon_0/lat_0/width$ --> <IMG WIDTH="109" HEIGHT="31" ALIGN="MIDDLE" BORDER="0" SRC="img12.png" ALT="$lon_0/lat_0/width$"> <BR> <P> where (<IMG WIDTH="62" HEIGHT="29" ALIGN="MIDDLE" BORDER="0" SRC="img10.png" ALT="$lon_0, lat_0$">) is the center of the map (projection). As an example we will try <P> <PRE> pscoast -R0/360/-90/90 -JG280/30/6i -Bg30/g15 -Dc -A5000 -Gwhite \ -SDarkTurquoise -P > map.ps </PRE> <P> <BR><HR> <!--Table of Child-Links--> <A NAME="CHILD_LINKS"><STRONG>Subsections</STRONG></A> <UL> <LI><A NAME="tex2html815" HREF="node30.html">1.4.5.1 Exercises</A> </UL> <!--End of Table of Child-Links--> <HR> <!--Navigation Panel--> <A NAME="tex2html813" HREF="node30.html"> <IMG WIDTH="37" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="next" SRC="next.png"></A> <A NAME="tex2html807" HREF="node20.html"> <IMG WIDTH="26" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="up" SRC="up.png"></A> <A NAME="tex2html801" HREF="node28.html"> <IMG WIDTH="63" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="previous" SRC="prev.png"></A> <A NAME="tex2html809" HREF="node1.html"> <IMG WIDTH="65" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="contents" SRC="contents.png"></A> <A NAME="tex2html811" HREF="node63.html"> <IMG WIDTH="43" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="index" SRC="index.png"></A> <BR> <B> Next:</B> <A NAME="tex2html814" HREF="node30.html">1.4.5.1 Exercises</A> <B> Up:</B> <A NAME="tex2html808" HREF="node20.html">1.4 Laboratory Exercises</A> <B> Previous:</B> <A NAME="tex2html802" HREF="node28.html">1.4.4.1 Exercises</A> <B> <A NAME="tex2html810" HREF="node1.html">Contents</A></B> <B> <A NAME="tex2html812" HREF="node63.html">Index</A></B> <!--End of Navigation Panel--> <ADDRESS> Paul Wessel 2011-02-27 </ADDRESS> </BODY> </HTML>