C++ String Switch v2

while (sscanf(remainder, "%s%n", buf, &consumed) == 1) {
  string value;
  string flag = buf;
  size_t eqAt = flag.find('=');
  if (eqAt != string::npos) {
    value = flag.substr(eqAt + 1);
    flag.erase(eqAt);
  }
  switch (hash(flag)) {
    case str_case(flag, "Blends") {
      tileProp.blends = true;
      break;
    }
    case str_case(flag, "Framed") {
      tileProp.isFramed = true;
      break;
    }
    case str_case(flag, "UnFramed") {
      break;
    }
    case str_case(flag, "Solid") {
      tileProp.isSolid = true;
      break;
    }
    case str_case(flag, "SolidTop") {
      tileProp.topIsSolid = true;
      break;
    }
    case str_case(flag, "Platform") {
      tileProp.isPlatform = true;
      break;
    }
    case str_case(flag, "Merge") {
      tileProp.blendWith = atol(value.c_str());
      break;
    }
    case str_case(flag, "Stone") {
      tileProp.isStone = true;
      break;
    }
    case str_case(flag, "Grass") {
      tileProp.isGrass = true;
      break;
    }
    case str_case(flag, "OnCeil") {
      tileProp.placement = TilePlacement::ON_CEILING;
      break;
    }
    case str_case(flag, "OnFaces") {
      tileProp.placement = TilePlacement::ON_FACES;
      break;
    }
    case str_case(flag, "OnFloorSurf") {
      tileProp.placement = TilePlacement::ON_FACES;
      break;
    }
    case str_case(flag, "OnFloor") {
      tileProp.placement = TilePlacement::ON_FLOOR;
      break;
    }
    case str_case(flag, "OnSurf") {
      tileProp.placement = TilePlacement::ON_SURFACES;
      break;
    }
    case str_case(flag, "OnTorch") {
      tileProp.placement = TilePlacement::ON_TORCH_PTS;
      break;
    }
    case str_case(flag, "OnWall") {
      tileProp.placement = TilePlacement::ON_WALLS;
      break;
    }
    case str_case(flag, "AsDoor") {
      tileProp.placement = TilePlacement::AS_DOOR;
      break;
    }
    case str_case(flag, "Light") {
      tileProp.isLightSource = true;
      break;
    }
    case str_case(flag, "TX") {
      tileProp.tX = atol(value.c_str());
      break;
    }
    case str_case(flag, "TY") {
      tileProp.tY = atol(value.c_str());
      break;
    }
    default:
      fprintf(stderr, "Unknown flag %s\n", flag.c_str());
      return 2;
  }
  remainder += consumed;
}

// The magic
constexpr int filthyHash(const char *x, int y, int z, int res) {
  return z < y
      ? filthyHash(x, y, z + 1, (int)((long)res * 31 + x[z]))
      : res;
}
constexpr int cleanHash(const char* x, int y) {
  return filthyHash(x, y, 0, 0) << 4 | (y & ((1 << 4) - 1));
}
template<size_t N> constexpr int dirtyHash(const char (&x)[N]) {
  return cleanHash(x, N - 1);
}
int hash(string x) {
  return cleanHash(x.c_str(), x.length());
}
#define str_case(key, x) dirtyHash(x): if ((key) == (x))