ogxp_tiler_preview.py creates a shapefile showing the extents of the orthoimage tiles that
will be created by ogxp_tiler_def.py without actually creating the tiled images. The shapefile
grid polygons are attributed with tile image name that will be referenced in the custom scenery
created by ogxp_basemesh.py.

ogxp_tiler_preview.py is useful for manually selecting those tiles for special fade treatment
in the top, bottom, right, left, trcorn, brcorn, blcorn, tlcorn, trcorn_neg, brcorn_neg, blcorn_neg,
and tlcorn_neg lists.


Input the scenery name and tile size and whether input orthoimage should be resized to even multiple of tile size.