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6.2.3 Perspective projection (-Jg -JG)

The perspective projection imitates in 2 dimensions the 3-dimensional view of the earth from space. The implementation in GMT is very flexible, and thus requires many input variables. Those are listed and explained below, with the values used in Figure 6.10 between brackets.

The imagined view of northwest Europe from a Space Shuttle at 230 km looking due east is thus accomplished by the following pscoast command:




pscoast -Rg -JG4/52/230/90/60/180/60/60/5i -B2g2/1g1 -Ia -Di -Glightgray -Wthinnest -P \
        --ANNOT_MIN_SPACING=0.25i > GMT_perspective.ps


Figure 6.10: View from the Space Shuttle in Perspective projection.
\includegraphics{scripts/GMT_perspective}


next up previous contents index
Next: 6.2.4 Orthographic projection (-Jg Up: 6.2 Azimuthal projections Previous: 6.2.2.3 General stereographic map   Contents   Index
Paul Wessel 2008-05-15