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/*
* This code written 2003
* by Max Gensthaler <Max@Gensthaler.de>
* Distributed under the Gnu Public License (GPL)
*
* Gensthaler called it 'ppmglobemap'.
*
* Translations of comments and C dialect by Bryan Henderson May 2003.
*/
#define _XOPEN_SOURCE /* get M_PI in math.h */
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <math.h>
#include "ppm.h"
#include "colorname.h"
#include "shhopt.h"
#include "mallocvar.h"
struct cmdlineInfo {
/* All the information the user supplied in the command line,
in a form easy for the program to use.
*/
const char * inputFileName; /* Filename of input files */
unsigned int stripcount;
const char * background;
unsigned int closeok;
};
static void
parseCommandLine(int argc, char ** argv,
struct cmdlineInfo * const cmdlineP) {
/*----------------------------------------------------------------------------
Note that the file spec array we return is stored in the storage that
was passed to us as the argv array.
-----------------------------------------------------------------------------*/
optEntry *option_def;
/* Instructions to optParseOptions3 on how to parse our options.
*/
optStruct3 opt;
unsigned int option_def_index;
unsigned int backgroundSpec;
MALLOCARRAY_NOFAIL(option_def, 100);
option_def_index = 0; /* incremented by OPTENT3 */
OPTENT3(0, "background", OPT_STRING, &cmdlineP->background,
&backgroundSpec, 0);
OPTENT3(0, "closeok", OPT_FLAG, NULL,
&cmdlineP->closeok, 0);
opt.opt_table = option_def;
opt.short_allowed = FALSE; /* We have no short (old-fashioned) options */
opt.allowNegNum = FALSE; /* We have no parms that are negative numbers */
optParseOptions3(&argc, argv, opt, sizeof(opt), 0);
/* Uses and sets argc, argv, and some of *cmdlineP and others. */
if (!backgroundSpec)
cmdlineP->background = NULL;
if (argc - 1 < 1)
pm_error("You must specify at least one argument: the strip count");
else {
int const stripcount = atoi(argv[1]);
if (stripcount <= 0)
pm_error("The strip count must be positive. You specified %d",
stripcount);
cmdlineP->stripcount = stripcount;
if (argc-1 < 2)
cmdlineP->inputFileName = "-";
else
cmdlineP->inputFileName = argv[2];
if (argc - 1 > 2)
pm_error("There are at most two arguments: strip count "
"and input file name. "
"You specified %u", argc-1);
}
}
int
main(int argc, char *argv[]) {
struct cmdlineInfo cmdline;
FILE * ifP;
pixel ** srcPixels;
pixel ** dstPixels;
int srcCols, srcRows;
unsigned int dstCols, dstRows;
pixval srcMaxval, dstMaxval;
unsigned int stripWidth;
/* Width in pixels of each strip. In the output image, this means
the rectangular strip in which the lens-shaped foreground strip
is placed..
*/
unsigned int row;
pixel backgroundColor;
ppm_init(&argc, argv);
parseCommandLine(argc, argv, &cmdline);
ifP = pm_openr(cmdline.inputFileName);
srcPixels = ppm_readppm(ifP, &srcCols, &srcRows, &srcMaxval);
pm_close(ifP);
stripWidth = srcCols / cmdline.stripcount;
if (stripWidth < 1)
pm_error("You asked for %u strips, but the image is only "
"%u pixels wide, so that is impossible.",
cmdline.stripcount, srcCols);
dstCols = stripWidth * cmdline.stripcount;
dstRows = srcRows;
dstMaxval = srcMaxval;
if (cmdline.background == NULL)
PPM_ASSIGN(backgroundColor, 0, 0, 0);
else
pm_parse_dictionary_name(cmdline.background,
dstMaxval, cmdline.closeok,
&backgroundColor);
dstPixels = ppm_allocarray(dstCols, dstRows);
for (row = 0; row < dstRows; ++row) {
double const factor = sin(M_PI * row / dstRows);
/* Amount by which we squeeze the foreground image of each
strip in this row.
*/
int const stripBorder = (int)((stripWidth*(1.0-factor)/2.0) + 0.5);
/* Distance from the edge (either one) of a strip to the
foreground image within that strip -- i.e. number of pixels
of background color, which User will cut out with scissors
after he prints the image.
*/
unsigned int dstCol;
for (dstCol = 0; dstCol < dstCols; ++dstCol) {
if (dstCol % stripWidth < stripBorder
|| dstCol % stripWidth >= stripWidth - stripBorder)
dstPixels[row][dstCol] = backgroundColor;
else {
unsigned int const leftEdge =
(dstCol / stripWidth) * stripWidth;
unsigned int const srcCol = leftEdge +
(int)((dstCol % stripWidth - stripBorder) / factor + 0.5);
dstPixels[row][dstCol] = srcPixels[row][srcCol];
}
}
}
ppm_writeppm(stdout, dstPixels, dstCols, dstRows, dstMaxval, 0);
return 0;
}
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