Transparency question

[teisco]

I am working on a paint for a plane that has two decals. I want to make both decals totally transparent so I can apply proper graphics to that area. I found with the main decal that if I make the alpha totally black and the decal or bmp totally white it will be fully transparent in game.

The other decal does not work that way. I tried the same technique but it turned it to chrome instead. Why does one work and not the other?

What decides if a bmp is going to be chrom or transparent?

[garryrussell]

The model parts are set by the modeller to be either refective or transparent with apha.

This is saved into the part so without the original source files there is nothing you can do.

[teisco]

Ok but in this case both were decals so both were supposed to be transparent except for the graphic. Both were on 1024 sheets with other regular graphics but one could be make fully transparent by the black alpha/white bmp method but the other just turned to chrome.