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diff --git a/upstream/mageia-cauldron/man1/pamcrater.1 b/upstream/mageia-cauldron/man1/pamcrater.1 new file mode 100644 index 00000000..0af58fc4 --- /dev/null +++ b/upstream/mageia-cauldron/man1/pamcrater.1 @@ -0,0 +1,234 @@ +\ +.\" 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 "Pamcrater User Manual" 0 "03 November 2014" "netpbm documentation" + +.SH NAME + +pamcrater - create cratered terrain by fractal forgery + + +.UN synopsis +.SH SYNOPSIS + +\fBpamcrater\fP + +[\fB-number\fP \fIn\fP] + +[\fB-height\fP \fIpixels\fP] + +[\fB-width\fP \fIpixels\fP] + +[\fB-randomseed=\fP\fIinteger\fP] + +[\fB-verbose\fP] + +.UN description +.SH DESCRIPTION +.PP +This program is part of +.BR "Netpbm" (1)\c +\&. +.PP +\fBpamcrater\fP creates a PAM image which is a terrain map (not a visual +image) of cratered terrain. The terrain is as if a given number of impacts +into a surface create craters with random position and size. +.PP +The size distribution of the craters is based on a power law which results +in many more small craters than large ones. The number of craters of a given +size varies as the reciprocal of the area as described on pages 31 and 32 of +Peitgen and Saupe[1]; cratered bodies in the Solar System are observed to obey +this relationship. The formula used to obtain crater radii governed by this +law from a uniformly distributed pseudorandom sequence was developed by Rudy +Rucker. +.PP +A terrain map is a two dimensional map of terrain elevations. the PAM +image that \fBpamcrater\fP produces is therefore not a visual image but a +depth-one image of tuple type "elevation", with the sample value +being proportional to an elevation. +.PP +You can visualize the terrain map by generating a shaded relief image of it +with \fBpamshadedrelief\fP. +.PP +High resolution images with large numbers of +craters often benefit from being piped through \fBpnmsmooth\fP. The +averaging performed by this process eliminates some of the jagged pixels and +lends a mellow ``telescopic image'' feel to the overall picture. +.PP +\fBpamcrater\fP generates only small craters, which are hemispherical in +shape (regardless of the incidence angle of the impacting body, as long as the +velocity is sufficiently high). Large craters, such as Copernicus and Tycho +on the Moon, have a ``walled plain'' shape with a cross-section more like: + +.nf + /\e /\e + _____/ \e____________/\e____________/ \e_____ + +.fi +.PP +Larger craters should really use this profile, including the central +peak, and totally obliterate the pre-existing terrain. +.PP +The maxval of the PAM image is always 65535. +.PP +The randomness in the image is limited before Netpbm 10.37 (December +2006) -- if you run the program twice in the same second, you may get +identical output. + + +.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 +\&), \fBpamcrater\fP recognizes the following +command line options: +.PP +All options can be abbreviated to their shortest unique prefix. + + +.TP +\fB-number\fP \fIn\fP +This causes \fBpamcrater\fP to generate \fIn\fP craters. If you do not +specify \fB-number\fP, it generates 50000 craters. Don't expect to see them +all! For every large crater there are many, many more tiny ones which tend +simply to erode the landscape. In general, the more craters you specify, the +more realistic the result; ideally you want the entire terrain to have been +extensively turned over again and again by cratering. High resolution images +containing five to ten million craters are stunning but take longer to create. + +.TP +\fB-height\fP \fIheight\fP +This sets the height of the generated image to \fIheight\fP pixels. +The default height is 256 pixels. + +.TP +\fB-width\fP \fIwidth\fP +This sets the width of the generated image to \fIwidth\fP pixels. The +default width is 256 pixels. + +.TP +\fB-randomseed=\fP\fIinteger\fP +This is the seed for the random number generator that generates the +pixels. +.sp +Use this to ensure you get the same image on separate invocations. +.sp +By default, \fBpamcrater\fP uses a seed derived from the time of day and +process ID, which gives you fairly uncorrelated results in multiple +invocations. +.sp +This option was new in Netpbm 10.61 (December 2012). + +.TP +\fB-verbose\fP +This causes \fBpamcrater\fP to issue additional messages about what it +is doing. +.sp +This option was new in Neptbm 10.69 (December 2014). + + + +.UN examples +.SH EXAMPLES + +.nf +\f(CW + $ pamcrater | pamshadedrelief | pamx + + $ pamcrater -number=500000 -height=1000 -width=1000 >craters.pam +\fP + +.fi + +.UN designnotes +.SH DESIGN NOTES +.PP +Real craters have two distinct morphologies. + + +.UN seealso +.SH SEE ALSO +.BR "pamshadedrelief" (1)\c +\&, +.BR "ppmrelief" (1)\c +\&, +.BR "pnmsmooth" (1)\c +\& +.BR "pam" (1)\c +\&, + + +.TP +[1] +Peitgen, H.-O., and Saupe, D. eds., The Science Of Fractal Images, +New York: Springer Verlag, 1988. + + + +.UN author +.SH AUTHOR +.PP +\fBpgmcrater\fP, from which this is derived, was written by John Walker: + +.nf +John Walker +Autodesk SA +Avenue des Champs-Montants 14b +CH-2074 MARIN +Suisse/Schweiz/Svizzera/Svizra/Switzerland + \fBUsenet:\fP\fIkelvin@Autodesk.com\fP + \fBFax:\fP038/33 88 15 + \fBVoice:\fP038/33 76 33 + +.fi +.PP +Permission to use, copy, modify, and distribute this software and +its documentation for any purpose and without fee is hereby granted, +without any conditions or restrictions. This software is provided +"as is" without express or implied warranty. + + +.UN history +.SH HISTORY +.PP +John Walker wrote \fBpgmcrater\fP in 1991 and it was included in Pbmplus. +\fBpgmcrater\fP did the equivalent of \f(CWpamcrater | pamshadedrelief\fP. +In Netpbm 10.68 (September 2014), Bryan Henderson split the functions +of \fBpgmcrater\fP into two programs, one (\fBpamcrater\fP) to compute +elevations, and the other (\fBpamshadedrelief\fP) to generate a shaded relief +visual image showing those elevations. Bryan did this because it is more in +keeping with Netpbm's modular architecture, and because +the \fBpamshadedrelief\fP might be useful with other inputs. +.PP +(Like all Netpbm programs, \fBpgmcrater\fP was not static between the two +events described above; minor changes, including replacement of most of the +code, happened in between). +.PP +The original 1991 \fBpgmcrater\fP manual contains the following: + +.SS PLUGWARE! +.PP +If you like this kind of stuff, you may also enjoy "James Gleick's +Chaos--The Software" for MS-DOS, available for $59.95 from your +local software store or directly from Autodesk, Inc., Attn: Science +Series, 2320 Marinship Way, Sausalito, CA 94965, USA. Telephone: +(800) 688-2344 toll-free or, outside the U.S. (415) 332-2344 Ext +4886. Fax: (415) 289-4718. "Chaos--The Software" includes a more +comprehensive fractal forgery generator which creates +three-dimensional landscapes as well as clouds and planets, plus five +more modules which explore other aspects of Chaos. The user guide of +more than 200 pages includes an introduction by James Gleick and +detailed explanations by Rudy Rucker of the mathematics and algorithms +used by each program. +.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/pamcrater.html +.PP
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