gdxpm.c

Linux/Unix下的绘图函数库（Graphic Drawing Library）

/* 
   add ability to load xpm files to gd, requires the xpm
   library.
   [e-mail] 
   http://www.csn.ul.ie/~caolan
 */

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "gd.h"
#include "gdhelpers.h"

#ifndef HAVE_LIBXPM
BGD_DECLARE(gdImagePtr) gdImageCreateFromXpm (char *filename)
{
  fprintf (stderr, "libgd was not built with xpm support\n");
  return (NULL);
}

#else

#include <X11/xpm.h>

BGD_DECLARE(gdImagePtr) gdImageCreateFromXpm (char *filename)
{
  XpmInfo info;
  XpmImage image;
  int i, j, k, number;
  char buf[5];
  gdImagePtr im = 0;
  int *pointer;
  int red = 0, green = 0, blue = 0;
  int *colors;
  int ret;

  ret = XpmReadFileToXpmImage (filename, &image, &info);
  if (ret != XpmSuccess)
    return 0;

  if (!(im = gdImageCreate (image.width, image.height)))
    return 0;

  number = image.ncolors;
  colors = (int *) gdMalloc (sizeof (int) * number);
  if (colors == NULL)
    return (0);
  for (i = 0; i < number; i++)
    {
      switch (strlen (image.colorTable[i].c_color))
	{
	case 4:
	  buf[1] = '\0';
	  buf[0] = image.colorTable[i].c_color[1];
	  red = strtol (buf, NULL, 16);

	  buf[0] = image.colorTable[i].c_color[3];
	  green = strtol (buf, NULL, 16);

	  buf[0] = image.colorTable[i].c_color[5];
	  blue = strtol (buf, NULL, 16);
	  break;
	case 7:
	  buf[2] = '\0';
	  buf[0] = image.colorTable[i].c_color[1];
	  buf[1] = image.colorTable[i].c_color[2];
	  red = strtol (buf, NULL, 16);

	  buf[0] = image.colorTable[i].c_color[3];
	  buf[1] = image.colorTable[i].c_color[4];
	  green = strtol (buf, NULL, 16);

	  buf[0] = image.colorTable[i].c_color[5];
	  buf[1] = image.colorTable[i].c_color[6];
	  blue = strtol (buf, NULL, 16);
	  break;
	case 10:
	  buf[3] = '\0';
	  buf[0] = image.colorTable[i].c_color[1];
	  buf[1] = image.colorTable[i].c_color[2];
	  buf[2] = image.colorTable[i].c_color[3];
	  red = strtol (buf, NULL, 16);
	  red /= 64;

	  buf[0] = image.colorTable[i].c_color[4];
	  buf[1] = image.colorTable[i].c_color[5];
	  buf[2] = image.colorTable[i].c_color[6];
	  green = strtol (buf, NULL, 16);
	  green /= 64;

	  buf[0] = image.colorTable[i].c_color[7];
	  buf[1] = image.colorTable[i].c_color[8];
	  buf[2] = image.colorTable[i].c_color[9];
	  blue = strtol (buf, NULL, 16);
	  blue /= 64;
	  break;
	case 13:
	  buf[4] = '\0';
	  buf[0] = image.colorTable[i].c_color[1];
	  buf[1] = image.colorTable[i].c_color[2];
	  buf[2] = image.colorTable[i].c_color[3];
	  buf[3] = image.colorTable[i].c_color[4];
	  red = strtol (buf, NULL, 16);
	  red /= 256;

	  buf[0] = image.colorTable[i].c_color[5];
	  buf[1] = image.colorTable[i].c_color[6];
	  buf[2] = image.colorTable[i].c_color[7];
	  buf[3] = image.colorTable[i].c_color[8];
	  green = strtol (buf, NULL, 16);
	  green /= 256;

	  buf[0] = image.colorTable[i].c_color[9];
	  buf[1] = image.colorTable[i].c_color[10];
	  buf[2] = image.colorTable[i].c_color[11];
	  buf[3] = image.colorTable[i].c_color[12];
	  blue = strtol (buf, NULL, 16);
	  blue /= 256;
	  break;
	}


      colors[i] = gdImageColorResolve (im, red, green, blue);
      if (colors[i] == -1)
	fprintf (stderr, "ARRRGH\n");
    }

  pointer = (int *) image.data;
  for (i = 0; i < image.height; i++)
    {
      for (j = 0; j < image.width; j++)
	{
	  k = *pointer++;
	  gdImageSetPixel (im, j, i, colors[k]);
	}
    }
  gdFree (colors);
  return (im);
}
#endif /* HAVE_LIBXPM */