getCaseArr.c

int* getCaseArr( int* isFilled, int h, int w)
{
  int* caseArr;
  caseArr = (int*) malloc( h*w*sizeof(int));

  for( int i = 0; i < h-1; i++)
  {
    for( int j = 0; j < w-1; j++)
      caseArr[ i*w + j] = 0xFF & (isFilled[ (i+1)*w + j] | 
                                  isFilled[ (i+1)*w + j + 1] << 1 |  
                                  isFilled[ i*w + j + 1] << 2 | 
                                  isFilled[ i*w + j] << 3);
  }

  return caseArr;
}