BMPs vs DXT

[jjcargo]

are there sustancial differences between good old BMPs
and DXTs ?   is it mandatory to move to dxts?

[RollerBall]

You can only get reflections and transparency on coloured objects (as distinct from just totally see-through) if you use extended bmps with alpha channels. Also extended bmps tend to be slightly smaller than normal equivalents which makes them a bit more efficient in the later sim versions that can use them

[wji]

DXTbmp.exe can be found HERE (page bottom)