Why not?

src/cmd/map/mapdemo.rc

@@ -0,0 +1,83 @@
+#!/bin/rc
+
+fn demo {proj=$1;	shift;
+	label=$1;	shift;
+	{	echo 'o'
+		echo 'ra -8192 -8492 8192 8492'
+		echo 'e'
+		echo 'm -8192 8192'
+		echo t $type
+		echo 'm -8192 -8192'
+		echo t $proj - $label
+		MAP=world MAPDIR=/lib/map map $proj $* -s -d 5
+	} 
+	sleep 5
+}
+
+rfork en
+{
+type='Equatorial projections centered on long. 0. Parallels are straight lines.'
+
+demo mercator 'equally spaced straight meridians, conformal, straight compass courses'
+demo sinusoidal 'equally spaced parallels, equal-area, same as bonne(0)'
+demo cylequalarea 'equally spaced straight meridians, equal-area, true scale on Eq' 0
+demo cylindrical 'central projection on tangent cylinder'
+demo rectangular 'equally spaced parallels, equally spaced straight meridians, true scale on Eq' 0
+demo gall 'parallels spaced stereographically on prime meridian, equally spaced straight meridians, true scale on Eq' 0
+demo mollweide '(homalographic) equal-area, hemisphere is a circle'
+demo gilbert 'globe mapped conformally on hemisphere, viewed orthographically'
+
+type='Azimuthal: centered on the North Pole, Parallels are concentric circles, Meridians are equally spaced radial lines'
+
+demo azequidistant 'equally spaced parallels, true distances from pole'
+demo azequalarea 'equal area'
+demo gnomonic 'central projecton on tangent plane, straight great circles'
+demo perspective 'viewed along earth''s axis 2 earth radii from center of earth' 2
+demo orthographic 'viewed from infinity'
+demo stereographic 'conformal, projected from opposite pole'
+demo laue 'radius = tan(2\(mu colatitude ), used in xray crystallography'
+demo fisheye 'fisheye view of stereographic map, index of refraction 2' 2 -o 40.75 74
+demo newyorker 'New Yorker map from viewing pedestal of radius .5' .5 -o 40.75 74
+
+type='Polar conic projections symmetric about the Prime Meridian. Parallels are segments of concentric circles.'
+
+demo conic 'central projection on cone tangent at 40' 40
+demo simpleconic 'equally spaced parallels, true scale on 20 and 50' 20 50
+demo lambert 'conformal, true scale on 20 and 50' 20 50
+demo albers 'equal-area, true scale on 20 and 50' 20 50
+demo bonne 'equally spaced parallels, equal-area, parallel 40 developed from tangent cone' 40
+
+type='Projections with bilateral symmetry about the Prime Meridian and the equator.'
+
+demo polyconic 'parallels developed from tangent cones, equally spaced along Prime Meridian'
+demo aitoff 'equal-area projection of globe onto 2-to-1 ellipse, based on azequalarea'
+demo lagrange 'conformal, maps whole sphere into a circle'
+demo bicentric 'points plotted at true azimuth from two centers on the equator at longitudes +-40, great circles are straight lines' 40
+demo elliptic 'points are plotted at true distance from two centers on the equator at longitudes +-40' 40
+demo globular 'hemisphere is circle, circular meridians and parallels'
+demo vandergrinten 'sphere is circle, meridians as in globular, circular arc parallels resemble mercator'
+
+type='Doubly periodic conformal projections.'
+
+demo guyou 'W and E hemispheres are square'
+demo square 'World is square with Poles at diagonally opposite corners'
+demo tetra 'map on tetrahedron with edge tangent to Prime Meridian at S Pole, unfolded into equilateral triangle'
+demo hex 'world is hexagon centered on N Pole, N and S hemispheres are equilateral
+triangles'
+
+type='Retroazimuthal projections. Directions to center are true.'
+
+demo mecca 'equally spaced vertical meridians' 21.4 -o 90 -39.8
+demo homing 'distances to Mecca are true' 21.4 -o 90 -39.8
+
+type='Miscellaneous projections.'
+
+demo harrison 'oblique perspective from above the North Pole, 2 earth radii from the earth, looking along the Date Line 40 degrees off vertical' 2 40
+demo trapezoidal 'equally spaced parallels, straight meridians equally spaced along parallels, true scale at 20 and 50 on Prime Meridian' 20 50
+demo lune 'conformal, polar cap above Eq is 60-degree lune' 0 60
+
+type='Maps based on the spheroid'
+
+demo sp_mercator 'equally spaced straight meridians, conformal'
+demo sp_albers 'equal-area, true scale on 20 and 50' 20 50
+} | plot