// Compile with:
// g++ ddvdatamaker.cpp -o ddvdatamaker

//  Makes a ddv file ddvdatatest with unsigned char (byte) data.  The data array 
//  contains the slice number of each x-y slice as its data.  To make 
//  another data type, change the data type in line 15, 21, 50, 51, 54, and 59.

#include <stdio.h>
#include <string.h>

int main(int argv, char **argc)
{
int i, j, num_x, num_y, num_z;
float value, x_spacing, y_spacing, z_spacing;
unsigned char *data;
FILE *out;

  out = fopen("ddvdatatest","w");
  fprintf(out,"ver.0001");
//  Data type:
  i = 1;  //  unsigned char (bytes)
//  i = 2;  //  unsigned shorts
//  i = 3;  //  integer data values
//  i = 3;  //  float data values
  fwrite(&i,1,sizeof(int),out);
  num_x = num_y = num_z = 64;
  fwrite(&num_x,1,sizeof(int),out);  //  x size
  fwrite(&num_y,1,sizeof(int),out);  //  y size
  fwrite(&num_z,1,sizeof(int),out);  //  z size
  i = num_x*num_y*num_z;
  fwrite(&i,1,sizeof(int),out);  //  x*y*z size
  x_spacing = 1.0;
  value = 0.0;
  for ( i = 0; i < num_x; i++ ) {   //  x spacing array 
      fwrite(&value,1,sizeof(float),out);
    value += x_spacing;
  }
  y_spacing = 1.0;
  value = 0.0;
  for ( i = 0; i < num_y; i++ ) {   //  y spacing array 
      fwrite(&value,1,sizeof(float),out);
    value += y_spacing;
  }
  z_spacing = 1.0;
  value = 0.0;
  for ( i = 0; i < num_z; i++ ) {   //  z spacing array 
      fwrite(&value,1,sizeof(float),out);
    value += z_spacing;
  }
  data = new unsigned char[num_x*num_y*num_z];  //  create a data array
  memset(data,0,num_x*num_y*num_z*sizeof(unsigned char));  //  initialize to value zero  
  for ( i = 0; i < num_z; i++ ) {
    for ( j = 0; j < num_x*num_y; j++ ) {
      data[j+i*num_x*num_y] = (unsigned char)i;
    }
  }
  fwrite(data,num_x*num_y*num_z,sizeof(unsigned char),out);
  fclose(out);
}