code: private void getBestOffset(final Projection pProjection, final PointL pOffset) {
  		final double powerDifference = pProjection.getProjectedPowerDifference();
  		final PointL center = pProjection.getLongPixelsFromProjected(
  				mProjectedCenter, powerDifference, false, null);
  		final Rect screenRect = pProjection.getIntrinsicScreenRect();
  		final double screenCenterX = (screenRect.left + screenRect.right) / 2.;
  		final double screenCenterY = (screenRect.top + screenRect.bottom) / 2.;
  		final double worldSize = TileSystem.MapSize(pProjection.getZoomLevel());
  		getBestOffset(center.x, center.y, screenCenterX, screenCenterY, worldSize, pOffset);
  	}
docs: Compute the pixel offset so that a list of pixel segments display in the best possible way:
  the center of all pixels is as close to the screen center as possible
  This notion of pixel offset only has a meaning on very low zoom level,
  when a GeoPoint can be projected on different places on the screen.