Maybe its worth to make a note in the wiki on how to name branches of brands like “BigC”, “TESCO Lotus”, “7-Eleven” or “Shell”.
The value for “name” should be “the common default name” (see Comment at http://wiki.openstreetmap.org/wiki/Map_Features#Name ). Some users might think that it should be the name in local language (thai), but this is wrong, imho. This misunderstanding maybe could be caused by the great number of imprecise text in the OSM wiki, which mainly focusses on tagging streets and places. But brand names differ a lot from street names.
name
This is the name, which is used by the company at the location of the tagged POI. For example the TESCO-Lotus superstores in thailand are all very clearly signed with “TESCO Lotus” (see picture at http://en.wikipedia.org/wiki/Tesco_Lotus ). This is also the name that is used in the logo on their website and that is printed on top of their platic bags.
name:en
The name written in latin letters. For TESCO-Lotus stores this would be the same, “TESCO Lotus”.
name:th
The name written in thai letters. For TESCO-Lotus stores this would be เทสโก้ โลตัส, because this is the official transcription that is used e.g. on the website of the company in thailand.
This seems to be very simple and clear to me.
But someone could also try to name a TESCO-Lotus store like this:
name = TESCO LOTUS
nat_name = เทสโก้ โลตัส
Would this be better? Is this the intension of “nat_name”?
Maybe it would be good to collect more examples. Maybe we should create a page for listing all big brands (supermarkets, fuel stations, …) with the correct tagging for thailand in the wiki.
What do you think?
EDIT:
Changed all names of “TESCO” into “TESCO-Lotus” because there seem to be different types of TESCO and Lotus stores in Thailand (e.g. hypermarkets, Tesco Lotus Express, Talad Lotus and Value Store outlets).