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diff --git a/upstream/fedora-40/man1/ppmglobe.1 b/upstream/fedora-40/man1/ppmglobe.1 new file mode 100644 index 00000000..5d396323 --- /dev/null +++ b/upstream/fedora-40/man1/ppmglobe.1 @@ -0,0 +1,161 @@ +\ +.\" This man page was generated by the Netpbm tool 'makeman' from HTML source. +.\" Do not hand-hack it! If you have bug fixes or improvements, please find +.\" the corresponding HTML page on the Netpbm website, generate a patch +.\" against that, and send it to the Netpbm maintainer. +.TH "Ppmglobe User Manual" 0 "23 February 2006" "netpbm documentation" + +.SH NAME +ppmglobe - generate strips to glue onto a sphere + +.UN synopsis +.SH SYNOPSIS + +\fBppmglobe\fP +[\fB-background=\fP\fIcolorname\fP] +[\fB-closeok\fP] +\fIstripcount\fP +[\fIfilename\fP] +.PP +Minimum unique abbreviation of option is acceptable. You may use double +hyphens instead of single hyphen to denote options. You may use white +space in place of the equals sign to separate an option name from its value. + + +.UN description +.SH DESCRIPTION +.PP +This program is part of +.BR "Netpbm" (1)\c +\&. +.PP +\fBppmglobe\fP does the inverse of a cylindrical projection of a +sphere. Starting with a cylindrical projection, it produces an image +you can cut up and glue onto a sphere to obtain the spherical image of +which it is the cylindrical projection. +.PP +What is a cylindrical projection? Imagine a map of the Earth on flat +paper. There are lots of different ways cartographers show the three +dimensional information in such a two dimensional map. The cylindrical +projection is one. You could make a cylindrical projection by tracing as +folows: wrap a rectangular sheet of paper around the globe, touching the globe +at the Equator. For each point of color on the globe, run a horizontal line +from the axis of the globe through that point and out to the paper. Mark the +same color on the paper there. Lay the paper out flat and you have a +cylindrical projection. +.PP +Here's where \fBppmglobe\fP comes in: Pass the image on that paper +through \fBppmglobe\fP and what comes out the other side looks something +like this: +.PP +.B Example of map of the earth run through ppmglobe +.IMG -C globe.jpg +.PP +You could cut out the strips and glue it onto a sphere and you'd +have a copy of the original globe. +.PP +Note that cylindrical projections are not what you normally see as +maps of the Earth. You're more likely to see a Mercator projection. +In the Mercator projection, the Earth gets stretched North-South as +well as East-West as you move away from the Equator. It was invented +for use in navigation, because you can draw straight compass courses +on it, but is used today because it is pretty. +.PP +You can find maps of planets at +.UR http://maps.jpl.nasa.gov +maps.jpl.nasa.gov +.UE +\&. + +.UN parameters +.SH PARAMETERS +.PP +\fIstripcount\fP is the number of strips \fBppmglobe\fP is to +generate in the output. More strips makes it easier to fit onto a +sphere (less stretching, tearing, and crumpling of paper), but makes +you do more cutting out of the strips. +.PP +The strips are all the same width. If the number of columns of +pixels in the image doesn't evenly divide by the number of strips, +\fBppmglobe\fP truncates the image on the right to create nothing but +whole strips. In the pathological case that there are fewer columns +of pixels than the number of strips you asked for, \fBppmglobe\fP +fails. +.PP +Before Netpbm 10.32 (February 2006), instead of truncating the image +on the right, \fBppmglobe\fP produces a fractional strip on the right. +.PP +\fIfilename\fP is the name of the input file. If you don't +specify this, \fBppmglobe\fP reads the image from Standard Input. + + +.UN options +.SH OPTIONS +.PP +In addition to the options common to all programs based on libnetpbm +(most notably \fB-quiet\fP, see +.UR index.html#commonoptions + Common Options +.UE +\&), \fBppmglobe\fP recognizes the following +command line options: + + + +.TP +\fB-background=\fP\fIcolorname\fP +This specifies the color that goes between the strips. +.sp +Specify the color (\fIcolor\fP) as described for the +.UR libnetpbm_image.html#colorname +argument of the \fBpnm_parsecolor()\fP library routine +.UE +\&. +.sp +The default is black. +.sp +This option was new in Netpbm 10.31 (December 2005). Before that, +the background is always black. + +.TP +\fB-closeok\fP +This means it is OK if the background isn't exactly the color you specify. +Sometimes, it is impossible to represent a named color exactly because of the +precision (i.e. maxval) of the image's color space. If you specify +\fB-closeok\fP and \fBppmglobe\fP can't represent the color you name +exactly, it will use instead the closest color to it that is possible. +If you don't specify \fBcloseok\fP, \fBppmglobe\fP fails in that +situation. +.sp +This option was new in Netpbm 10.31 (December 2005). + + + +.UN seealso +.SH SEE ALSO +.BR "ppm" (1)\c +\& +.BR "pnmmercator" (1)\c +\& + +.UN history +.SH HISTORY +.PP +\fBppmglobe\fP was new in Netpbm 10.16 (June 2003). +.PP +It is derived from Max Gensthaler's \fBppmglobemap\fP. + +.UN authors +.SH AUTHORS +.PP +\fIMax Gensthaler\fP +wrote a program he called +\fBppmglobemap\fP in June 2003 and suggested it for inclusion in +Netpbm. Bryan Henderson modified the code slightly and included it in +Netpbm as \fBppmglobe\fP. +.SH DOCUMENT SOURCE +This manual page was generated by the Netpbm tool 'makeman' from HTML +source. The master documentation is at +.IP +.B http://netpbm.sourceforge.net/doc/ppmglobe.html +.PP
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