code: @SuppressWarnings("ConstantConditions")
      static int xDivider(final int latMin, final int latMax) {
          assert latMin < latMax;
          if (latMin >= 0) {
              assert (latMax > latMin) && (latMin > 0);
              return X_DIVIDER_19[latMin >> 19];
          } else if (latMax >= 0) {
              assert (latMax > 0) && (0 > latMin);
              return X_DIVIDER_19[0];
          } else {
              assert (0 > latMax) && (latMax > latMin);
              return X_DIVIDER_19[(-latMax) >> 19];
          }
      }
docs: TODO: Need better names for minY and maxY.