/* 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 */