lbio.c

基于格子Boltzmann方法开源可视化软件的源代码 具有很高的实用价值。对学习LBM方法及其软件开发非常游泳

  int    **map;
  char   red_val, 
         green_val, 
         blue_val, 
         val;
  double min_rho, max_rho;

#if SAY_HI
  printf("rho2bmp() -- Hi!\n");
#endif /* SAY_HI */

  frame = time/lattice->param.FrameRate;

  sprintf( filename, "%dx%d.bmp", lattice->param.LX, lattice->param.LY);
  if( !( in = fopen( filename, "r")))
  {
    printf("rho2bmp() -- Error opening file \"%s\".\n", filename);
    exit(1);
  }

  // n = fread( void *BUF, size_t SIZE, size_t COUNT, FILE *FP);

  n = fread( &bmfh, sizeof(struct bitmap_file_header), 1, in );
  if( strncmp(bmfh.bfType,"BM",2))
  {
    printf("ERROR: Can't process this file type.  Exiting!\n");
    printf("\n");
    exit(1);
  }
  n = fread( &bmih, sizeof(struct bitmap_info_header), 1, in );
  int_ptr = (int*)bmih.biCompression;
  if( *int_ptr != 0)
  {
    printf("ERROR: Can't handle compression.  Exiting!\n");
    printf("\n");
    exit(1);
  }

  width_ptr = (int*)bmih.biWidth;
  height_ptr = (int*)bmih.biHeight;
  bitcount_ptr = (short int*)bmih.biBitCount;

  // Read palette entries, if applicable.
  if( *bitcount_ptr < 24)
  {
    n = (double)pow(2.,(double)*bitcount_ptr); // Num palette entries.
    for( i=0; i<n; i++)
    {
      k = fread( &rgb, sizeof(struct rgb_quad), 1, in );
      if( k!=1)
      {
        printf("Error reading palette entry %d.  Exiting!\n", i);
        exit(1);
      }
    }
  }

  fclose(in);

  // Bytes per row of the bitmap.
  bytes_per_row = 
    ((int)ceil(( (((double)(*width_ptr))*((double)(*bitcount_ptr)))/8.)));

  // Bitmaps pad rows to preserve 4-byte boundaries.
  // The length of a row in the file will be bytes_per_row + pad .
  pad = ((4) - bytes_per_row%4)%4;

  map = (int**)malloc( (lattice->param.LY)*sizeof(int*));
  for( j=0; j<(lattice->param.LY); j++)
  {
    map[j] = (int*)malloc( (lattice->param.LX)*sizeof(int));
  }
#if 0
  //memset( &(map[0][0]), -1, (lattice->param.LX)*(lattice->param.LY)*sizeof(int));
  memset( &(map[0][0]), -1, 29*sizeof(int));
#else
  for( j=0; j<lattice->param.LY; j++)
  {
    for( i=0; i<lattice->param.LX; i++)
    {
      map[j][i] = -1;
    }
  }
#endif

#if 0
  for( j=0; j<lattice->param.LY; j++)
  {
    for( i=0; i<lattice->param.LX; i++)
    {
      printf(" %d", map[j][i]);
    }
    printf("\n");
  }
  printf("\n");
#endif

  for( n=0; n<lattice->NumNodes; n++)
  {
    map[lattice->node[n].j][lattice->node[n].i] = lattice->node[n].n;
  }

#if 0
  for( j=0; j<lattice->param.LY; j++)
  {
    for( i=0; i<lattice->param.LX; i++)
    {
      printf(" %d", map[j][i]);
    }
    printf("\n");
  }
  printf("\n");
#endif

  compute_min_rho( lattice, &min_rho);
  compute_max_rho( lattice, &max_rho);

  sprintf( filename, "rho%dx%d_frame%04d.bmp", 
      lattice->param.LX, 
      lattice->param.LY, 
      frame);
  o = fopen( filename, "w+");

  fwrite( &bmfh, sizeof(struct bitmap_file_header), 1, o );
  fwrite( &bmih, sizeof(struct bitmap_info_header), 1, o );

  //for( j=lattice->param.LY-1; j>=0; j--)
  for( j=0; j<lattice->param.LY; j++)
  {
    for( i=0; i<lattice->param.LX; i++)
    {
      if(    map[j][i] != INACTIVE_NODE 
          //&& !( lattice->bc[ map[j][i]].bc_type & BC_SOLID_NODE)
          && lattice->bc[ map[j][i]].bc_type == /*FLUID_NODE*/0
        )
      {
        red_val = (char)0;
        green_val = (char)0;

        red_val = 
(char)round( 255.*(lattice->macro_vars[ map[j][i]].rho[0] - min_rho)/(max_rho-min_rho));
        blue_val = (char)255-red_val;

      } /* if( map[j][i] != INACTIVE_NODE) */

      else // map[j][i] == INACTIVE_NODE
      {
#if SOLID_COLOR_IS_CHECKERBOARD
        // Checkerboard pattern over the solids and boundary conditions.
        if( (i+j)%2)
        {
          red_val   = (char)200;
          green_val = (char)200;
          blue_val  = (char)200;
          val       = (char)200;
        }
        else
        {
          red_val   = (char)184;
          green_val = (char)184;
          blue_val  = (char)184;
          val       = (char)184;
        }
#else /* !( SOLID_COLOR_IS_CHECKERBOARD) */
#if SOLID_COLOR_IS_BLACK
        red_val   = (char)0;
        green_val = (char)0;
        blue_val  = (char)0;
        val       = (char)0;
#else /* !( SOLID_COLOR_IS_BLACK) */
        red_val   = (char)255;
        green_val = (char)255;
        blue_val  = (char)255;
        val       = (char)255;
#endif /* SOLID_COLOR_IS_BLACK */
#endif /* SOLID_COLOR_IS_CHECKERBOARD */

      } /* if( map[j][i] != INACTIVE_NODE) else */

//printf("blue_val( %d, %d) = %d\n", i, j, (int)blue_val);

      if( fwrite( &blue_val, 1, 1, o) != 1) { printf("BOOM!\n"); exit(1);}
      //printf("BING %d %d\n", i, j);
      if( fwrite( &green_val, 1, 1, o) != 1) { printf("BOOM!\n"); exit(1);}
      //printf("BING %d %d\n", i, j);
      if( fwrite( &red_val, 1, 1, o) != 1) { printf("BOOM!\n"); exit(1);}
      //printf("BING %d %d\n", i, j);
     
    } /* for( i=0; i<lattice->param.LY; i++) */

    // Pad for 4-byte boundaries.
    val = (char)0;
    for( i=0; i<pad; i++)
    {
      if( fwrite( &val, 1, 1, o) != 1) { printf("BOOM!\n"); exit(1);}
    }

  } /* for( j=0; j<lattice->param.LY; j++) */

  fclose(o);

#if VERBOSITY_LEVEL > 0
  printf("rho2bmp() -- Wrote file \"%s\".\n", filename);
#endif /* VERBOSITY_LEVEL > 0 */

#if SAY_HI
  printf("rho2bmp() -- Bye!\n");
  printf("\n");
#endif /* SAY_HI */

} /* rho2bmp( lattice_ptr lattice, int time) */

// void u2bmp( char *filename, int time)
//##############################################################################
//
// U 2 B M P 
//
void u2bmp( lattice_ptr lattice, int time)
{
  FILE   *in, 
         *o_u,
         *o_ux,
         *o_uy;
  int    i, j, 
         n, m;
  int    pad, 
         bytes_per_row;
  int    frame;
  char   k;
  char   b;
  struct bitmap_file_header bmfh;
  struct bitmap_info_header bmih;
  struct rgb_quad rgb;
  int    *int_ptr;
  short  int *short_int_ptr;
  int    *width_ptr;
  int    *height_ptr;
  short  int *bitcount_ptr;
  char   filename[1024];
  int    **map;
  char   red_val, 
         green_val, 
         blue_val, 
         val;
  double max_u[2], maxu;
  double u_x, u_y, u;

#if SAY_HI
  printf("u2bmp() -- Hi!\n");
#endif /* SAY_HI */

  frame = time/lattice->param.FrameRate;

  sprintf( filename, "%dx%d.bmp", lattice->param.LX, lattice->param.LY);
  if( !( in = fopen( filename, "r")))
  {
    printf("u2bmp() -- Error opening file \"%s\".\n", filename);
    exit(1);
  }

  // n = fread( void *BUF, size_t SIZE, size_t COUNT, FILE *FP);

  n = fread( &bmfh, sizeof(struct bitmap_file_header), 1, in );
  if( strncmp(bmfh.bfType,"BM",2))
  {
    printf("ERROR: Can't process this file type.  Exiting!\n");
    printf("\n");
    exit(1);
  }
  n = fread( &bmih, sizeof(struct bitmap_info_header), 1, in );
  int_ptr = (int*)bmih.biCompression;
  if( *int_ptr != 0)
  {
    printf("ERROR: Can't handle compression.  Exiting!\n");
    printf("\n");
    exit(1);
  }

  width_ptr = (int*)bmih.biWidth;
  height_ptr = (int*)bmih.biHeight;
  bitcount_ptr = (short int*)bmih.biBitCount;

  // Read palette entries, if applicable.
  if( *bitcount_ptr < 24)
  {
    n = (double)pow(2.,(double)*bitcount_ptr); // Num palette entries.
    for( i=0; i<n; i++)
    {
      k = fread( &rgb, sizeof(struct rgb_quad), 1, in );
      if( k!=1)
      {
        printf("Error reading palette entry %d.  Exiting!\n", i);
        exit(1);
      }
    }
  }

  fclose(in);

  // Bytes per row of the bitmap.
  bytes_per_row = 
    ((int)ceil(( (((double)(*width_ptr))*((double)(*bitcount_ptr)))/8.)));

  // Bitmaps pad rows to preserve 4-byte boundaries.
  // The length of a row in the file will be bytes_per_row + pad .
  pad = ((4) - bytes_per_row%4)%4;

  // Create a map from (i,j) space onto n index space.  This could be a 
  // bad idea in terms of memory usage.  But the purpose is to create a 
  // bitmap file.  If the domain is small enough to view as a BMP, then
  // it is small enough to manage in a 2D array like this...
  map = (int**)malloc( (lattice->param.LY)*sizeof(int*));
  for( j=0; j<(lattice->param.LY); j++)
  {
    map[j] = (int*)malloc( (lattice->param.LX)*sizeof(int));
  }
#if 0
  //memset( &(map[0][0]), -1, (lattice->param.LX)*(lattice->param.LY)*sizeof(int));
  memset( &(map[0][0]), -1, 29*sizeof(int));
#else
  for( j=0; j<lattice->param.LY; j++)
  {
    for( i=0; i<lattice->param.LX; i++)
    {
      map[j][i] = -1;
    }
  }
#endif

#if 0
  for( j=0; j<lattice->param.LY; j++)
  {
    for( i=0; i<lattice->param.LX; i++)
    {
      printf(" %d", map[j][i]);
    }
    printf("\n");
  }
  printf("\n");
#endif

  for( n=0; n<lattice->NumNodes; n++)
  {
    map[lattice->node[n].j][lattice->node[n].i] = lattice->node[n].n;
  }

#if 0
  for( j=0; j<lattice->param.LY; j++)
  {
    for( i=0; i<lattice->param.LX; i++)
    {
      printf(" %d", map[j][i]);
    }
    printf("\n");
  }
  printf("\n");
#endif

  compute_max_u( lattice, max_u);

  sprintf( filename, "u%dx%d_frame%04d.bmp", 
      lattice->param.LX, 
      lattice->param.LY, 
      frame);
  o_u = fopen( filename, "w+");

  sprintf( filename, "u_x%dx%d_frame%04d.bmp", 
      lattice->param.LX, 
      lattice->param.LY, 
      frame);
  o_ux = fopen( filename, "w+");

  sprintf( filename, "u_y%dx%d_frame%04d.bmp", 
      lattice->param.LX, 
      lattice->param.LY, 
      frame);
  o_uy = fopen( filename, "w+");

  fwrite( &bmfh, sizeof(struct bitmap_file_header), 1, o_u );
  fwrite( &bmih, sizeof(struct bitmap_info_header), 1, o_u );

  fwrite( &bmfh, sizeof(struct bitmap_file_header), 1, o_ux );
  fwrite( &bmih, sizeof(struct bitmap_info_header), 1, o_ux );

  fwrite( &bmfh, sizeof(struct bitmap_file_header), 1, o_uy);
  fwrite( &bmih, sizeof(struct bitmap_info_header), 1, o_uy);

  //for( j=lattice->param.LY-1; j>=0; j--)
  for( j=0; j<lattice->param.LY; j++)
  {
    for( i=0; i<lattice->param.LX; i++)
    {
      if(    map[j][i] != INACTIVE_NODE 
          //&& !( lattice->bc[ map[j][i]].bc_type & BC_SOLID_NODE)
          && lattice->bc[ map[j][i]].bc_type == /*FLUID_NODE*/0
        )
      {
#if 1
        blue_val  = (char)0;
        green_val = (char)0;
        red_val   = (char)0;

        u_x = (lattice->macro_vars[ map[j][i]].u[0]);
        u_y = (lattice->macro_vars[ map[j][i]].u[1]);

        u = sqrt(u_x*u_x + u_y*u_y);
        maxu = sqrt( max_u[0]*max_u[0] + max_u[1]*max_u[1]);

        if( lattice->bc[ map[j][i]].bc_type & BC_SOLID_NODE)
        {
          blue_val  = (char)round( 128.*fabs(u_x)/max_u[0]);
          green_val = (char)round( 128.*fabs(u_y)/max_u[1]);

        } /* if( lattice->bc[ map[j][i]].bc_type & BC_SOLID_NODE) */

        else // !( lattice->bc[ map[j][i]].bc_type & BC_SOLID_NODE)
        {
          blue_val  = (char)round(  255.*fabs(u_x)/max_u[0]);
          green_val = (char)round(  255.*fabs(u_y)/max_u[1]);
          red_val    = (char)round( 128.*fabs(u)/maxu);

        } /* if( lattice->bc[ map[j][i]].bc_type & BC_SOLID_NODE) else */
#else
        blue_val  = (char)255;
        green_val = (char)255;
        red_val   = (char)255;

        u = sqrt(u_x*u_x + u_y*u_y);
        maxu = sqrt( max_u[0]*max_u[0] + max_u[1]*max_u[1]);

        //if( fabs(u) > .1*maxu)
        //{
          green_val  = (char)round( 255.-255.*fabs(u)/maxu);
          red_val    = (char)round( 255.-255.*fabs(u)/maxu);
          blue_val    = (char)round( 255.-255.*fabs(u)/maxu);
        //}
        //else
        //{
        //  green_val  = (char)0;
        //  red_val    = (char)0;
        //  blue_val    = (char)0;
        //}
#endif

        val = (char)0;

      } /* if( map[j][i] != INACTIVE_NODE) */

      else // map[j][i] == INACTIVE_NODE
      {
#if SOLID_COLOR_IS_CHECKERBOARD
        // Checkerboard pattern over the solids and boundary conditions.
        if( (i+j)%2)
        {
          red_val   = (char)200;
          green_val = (char)200;
          blue_val  = (char)200;
          val       = (char)200;
        }
        else