/* glprgr.c */

/***********************************************************************

*  This code is part of GLPK (GNU Linear Programming Kit).

*

*  Copyright (C) 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008,

*  2009, 2010 Andrew Makhorin, Department for Applied Informatics,

*  Moscow Aviation Institute, Moscow, Russia. All rights reserved.

*  E-mail: <mao@gnu.org>.

*

*  GLPK is free software: you can redistribute it and/or modify it

*  under the terms of the GNU General Public License as published by

*  the Free Software Foundation, either version 3 of the License, or

*  (at your option) any later version.

*

*  GLPK is distributed in the hope that it will be useful, but WITHOUT

*  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY

*  or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public

*  License for more details.

*

*  You should have received a copy of the GNU General Public License

*  along with GLPK. If not, see <http://www.gnu.org/licenses/>.

***********************************************************************/

#define _GLPSTD_ERRNO

#define _GLPSTD_STDIO

#include "glpenv.h"

#include "glprgr.h"

#define xfault xerror

/***********************************************************************

*  NAME

*

*  rgr_write_bmp16 - write 16-color raster image in BMP file format

*

*  SYNOPSIS

*

*  #include "glprgr.h"

*  int rgr_write_bmp16(const char *fname, int m, int n, const char

*     map[]);

*

*  DESCRIPTION

*

*  The routine rgr_write_bmp16 writes 16-color raster image in

*  uncompressed BMP file format (Windows bitmap) to a binary file whose

*  name is specified by the character string fname.

*

*  The parameters m and n specify, respectively, the number of rows and

*  the numbers of columns (i.e. height and width) of the raster image.

*

*  The character array map has m*n elements. Elements map[0, ..., n-1]

*  correspond to the first (top) scanline, elements map[n, ..., 2*n-1]

*  correspond to the second scanline, etc.

*

*  Each element of the array map specifies a color of the corresponding

*  pixel as 8-bit binary number XXXXIRGB, where four high-order bits (X)

*  are ignored, I is high intensity bit, R is red color bit, G is green

*  color bit, and B is blue color bit. Thus, all 16 possible colors are

*  coded as following hexadecimal numbers:

*

*     0x00 = black         0x08 = dark gray

*     0x01 = blue          0x09 = bright blue

*     0x02 = green         0x0A = bright green

*     0x03 = cyan          0x0B = bright cyan

*     0x04 = red           0x0C = bright red

*     0x05 = magenta       0x0D = bright magenta

*     0x06 = brown         0x0E = yellow

*     0x07 = light gray    0x0F = white

*

*  RETURNS

*

*  If no error occured, the routine returns zero; otherwise, it prints

*  an appropriate error message and returns non-zero. */

static void put_byte(FILE *fp, int c)

{     fputc(c, fp);

      return;

}

static void put_word(FILE *fp, int w)

{     /* big endian */

      put_byte(fp, w);

      put_byte(fp, w >> 8);

      return;

}

static void put_dword(FILE *fp, int d)

{     /* big endian */

      put_word(fp, d);

      put_word(fp, d >> 16);

      return;

}

int rgr_write_bmp16(const char *fname, int m, int n, const char map[])

{     FILE *fp;

      int offset, bmsize, i, j, b, ret = 0;

      if (!(1 <= m && m <= 32767))

         xfault("rgr_write_bmp16: m = %d; invalid height\n", m);

      if (!(1 <= n && n <= 32767))

         xfault("rgr_write_bmp16: n = %d; invalid width\n", n);

      fp = fopen(fname, "wb");

      if (fp == NULL)

      {  xprintf("rgr_write_bmp16: unable to create `%s' - %s\n",

            fname, strerror(errno));

         ret = 1;

         goto fini;

      }

      offset = 14 + 40 + 16 * 4;

      bmsize = (4 * n + 31) / 32;

      /* struct BMPFILEHEADER (14 bytes) */

      /* UINT bfType */          put_byte(fp, 'B'), put_byte(fp, 'M');

      /* DWORD bfSize */         put_dword(fp, offset + bmsize * 4);

      /* UINT bfReserved1 */     put_word(fp, 0);

      /* UNIT bfReserved2 */     put_word(fp, 0);

      /* DWORD bfOffBits */      put_dword(fp, offset);

      /* struct BMPINFOHEADER (40 bytes) */

      /* DWORD biSize */         put_dword(fp, 40);

      /* LONG biWidth */         put_dword(fp, n);

      /* LONG biHeight */        put_dword(fp, m);

      /* WORD biPlanes */        put_word(fp, 1);

      /* WORD biBitCount */      put_word(fp, 4);

      /* DWORD biCompression */  put_dword(fp, 0 /* BI_RGB */);

      /* DWORD biSizeImage */    put_dword(fp, 0);

      /* LONG biXPelsPerMeter */ put_dword(fp, 2953 /* 75 dpi */);

      /* LONG biYPelsPerMeter */ put_dword(fp, 2953 /* 75 dpi */);

      /* DWORD biClrUsed */      put_dword(fp, 0);

      /* DWORD biClrImportant */ put_dword(fp, 0);

      /* struct RGBQUAD (16 * 4 = 64 bytes) */

      /* CGA-compatible colors: */

      /* 0x00 = black */         put_dword(fp, 0x000000);

      /* 0x01 = blue */          put_dword(fp, 0x000080);

      /* 0x02 = green */         put_dword(fp, 0x008000);

      /* 0x03 = cyan */          put_dword(fp, 0x008080);

      /* 0x04 = red */           put_dword(fp, 0x800000);

      /* 0x05 = magenta */       put_dword(fp, 0x800080);

      /* 0x06 = brown */         put_dword(fp, 0x808000);

      /* 0x07 = light gray */    put_dword(fp, 0xC0C0C0);

      /* 0x08 = dark gray */     put_dword(fp, 0x808080);

      /* 0x09 = bright blue */   put_dword(fp, 0x0000FF);

      /* 0x0A = bright green */  put_dword(fp, 0x00FF00);

      /* 0x0B = bright cyan */   put_dword(fp, 0x00FFFF);

      /* 0x0C = bright red */    put_dword(fp, 0xFF0000);

      /* 0x0D = bright magenta */ put_dword(fp, 0xFF00FF);

      /* 0x0E = yellow */        put_dword(fp, 0xFFFF00);

      /* 0x0F = white */         put_dword(fp, 0xFFFFFF);

      /* pixel data bits */

      b = 0;

      for (i = m - 1; i >= 0; i--)

      {  for (j = 0; j < ((n + 7) / 8) * 8; j++)

         {  b <<= 4;

            b |= (j < n ? map[i * n + j] & 15 : 0);

            if (j & 1) put_byte(fp, b);

         }

      }

      fflush(fp);

      if (ferror(fp))

      {  xprintf("rgr_write_bmp16: write error on `%s' - %s\n",

            fname, strerror(errno));

         ret = 1;

      }

fini: if (fp != NULL) fclose(fp);

      return ret;

}

/* eof */