void TIA::computeMissleMaskTable()

in atari_py/ale_interface/src/emucore/TIA.cxx [823:914]
78 lines of code
46 McCabe index (conditional complexity)

void TIA::computeMissleMaskTable()
{
  // First, calculate masks for alignment 0
  Int32 x, size, number;

  // Clear the missle table to start with
  for(number = 0; number < 8; ++number)
    for(size = 0; size < 4; ++size)
      for(x = 0; x < 160; ++x)
        ourMissleMaskTable[0][number][size][x] = false;

  for(number = 0; number < 8; ++number)
  {
    for(size = 0; size < 4; ++size)
    {
      for(x = 0; x < 160 + 72; ++x)
      {
        // Only one copy of the missle
        if((number == 0x00) || (number == 0x05) || (number == 0x07))
        {
          if((x >= 0) && (x < (1 << size)))
            ourMissleMaskTable[0][number][size][x % 160] = true;
        }
        // Two copies - close
        else if(number == 0x01)
        {
          if((x >= 0) && (x < (1 << size)))
            ourMissleMaskTable[0][number][size][x % 160] = true;
          else if(((x - 16) >= 0) && ((x - 16) < (1 << size)))
            ourMissleMaskTable[0][number][size][x % 160] = true;
        }
        // Two copies - medium
        else if(number == 0x02)
        {
          if((x >= 0) && (x < (1 << size)))
            ourMissleMaskTable[0][number][size][x % 160] = true;
          else if(((x - 32) >= 0) && ((x - 32) < (1 << size)))
            ourMissleMaskTable[0][number][size][x % 160] = true;
        }
        // Three copies - close
        else if(number == 0x03)
        {
          if((x >= 0) && (x < (1 << size)))
            ourMissleMaskTable[0][number][size][x % 160] = true;
          else if(((x - 16) >= 0) && ((x - 16) < (1 << size)))
            ourMissleMaskTable[0][number][size][x % 160] = true;
          else if(((x - 32) >= 0) && ((x - 32) < (1 << size)))
            ourMissleMaskTable[0][number][size][x % 160] = true;
        }
        // Two copies - wide
        else if(number == 0x04)
        {
          if((x >= 0) && (x < (1 << size)))
            ourMissleMaskTable[0][number][size][x % 160] = true;
          else if(((x - 64) >= 0) && ((x - 64) < (1 << size)))
            ourMissleMaskTable[0][number][size][x % 160] = true;
        }
        // Three copies - medium
        else if(number == 0x06)
        {
          if((x >= 0) && (x < (1 << size)))
            ourMissleMaskTable[0][number][size][x % 160] = true;
          else if(((x - 32) >= 0) && ((x - 32) < (1 << size)))
            ourMissleMaskTable[0][number][size][x % 160] = true;
          else if(((x - 64) >= 0) && ((x - 64) < (1 << size)))
            ourMissleMaskTable[0][number][size][x % 160] = true;
        }
      }

      // Copy data into wrap-around area
      for(x = 0; x < 160; ++x)
        ourMissleMaskTable[0][number][size][x + 160] = 
          ourMissleMaskTable[0][number][size][x];
    }
  }

  // Now, copy data for alignments of 1, 2 and 3
  for(uInt32 align = 1; align < 4; ++align)
  {
    for(number = 0; number < 8; ++number)
    {
      for(size = 0; size < 4; ++size)
      {
        for(x = 0; x < 320; ++x)
        {
          ourMissleMaskTable[align][number][size][x] = 
            ourMissleMaskTable[0][number][size][(x + 320 - align) % 320];
        }
      }
    }
  }
}