DDS vs TGA: An interesting problem. Help?

[sleighr]

Well, RTW does accept TGA files, including ones of a different size than the standard 256 x256 or 512 x 512 that DDS uses.

However, I can't seem to get the game to see the alpha channel. Strange. It sees it when you convert a DDS file to TGA, and I removed the DDS file to prove it. But with my outsized TGAs the alpha won't show up.

I have noticed that in Max that TGA files don't automatically show the alpha source as "image alpha" which it does for DDS files. Yet this is the same for 256 and 512s as well, and yet their alpha channels work.

Is there a way of assigning the alpha channel in Max that I don't know of? Or is it done in Photoshop? Is it due to the CAS exporter? Or what?

Anyone got a theory?

[Thor the Bassist]

Alpha channels are applied in your 2d design program (so yes Photoshop). I seem to remember that alpha channels dont convert on all converters although I do remember a strange problem with it only having the alpha when in dds format. You are best to create a new alpha channel when you have converted to tga.

The image alpha is just how max displays the alpha channel and has no effect on your image just the rendering in max. It will, however, show how the model will look in the game.

[sleighr]

Alpha channels are applied in your 2d design program (so yes Photoshop). I seem to remember that alpha channels dont convert on all converters although I do remember a strange problem with it only having the alpha when in dds format. You are best to create a new alpha channel when you have converted to tga.

The image alpha is just how max displays the alpha channel and has no effect on your image just the rendering in max. It will, however, show how the model will look in the game.

Thank you, but the problem is that the alpha WON'T show up in the game, no matter how it looks in Max. It does show up in info and unit cards, just not in textures. Which is strange, because I converted a vanilla RTW texture to TGA and it worked just fine, despite my renaming it and even assigning it to a different model. When I changed it's size, it didn't.

I do create new alpha channels when I make the texture - I have even used game DDS textures, resized and converted them to TGA while just adjusting the alpha, rather than creating a new one...just in case. The game doesn't have a problem with alpha with TGA files, so long as they are conversions of DDS (e.g. original game textures), I think. But so far, with my other TGAs, the alpha won't work.

A couple of things I have noticed: The alpha channel will show in Max if you click on "Image Alpha" in the Bitmap Parameters box in the Material Editor, but won't load automatically with TGAs as it does with DDS textures.

Also, when you load up a CAS file in Max, the texture looked for is automatically a DDS file, and will be listed as such in the Material Editor whether it exists or not. Even if your only file is a TGA (e.g. unit_newhastati.tga) it will come up as unit_newhastati.tga.dds when you load the model.

Maybe it's a MIP map thing?

[Thor the Bassist]

Also, when you load up a CAS file in Max, the texture looked for is automatically a DDS file, and will be listed as such in the Material Editor whether it exists or not. Even if your only file is a TGA (e.g. unit_newhastati.tga) it will come up as unit_newhastati.tga.dds when you load the model.

Maybe it's a MIP map thing?

Hmm how confusing. This could be an engine limit that it only uses alpha with dds.

The import thing will be because in the game it looks for a xxxxx.tga and it doesn't matter whether there's a .dds on the end whereas max will require the .dds. So in the code in a cas file there will be

texture xxx/xxxxxxx/xxxx/xxx.tga

and the game will look for this and will still find a dds file but max will need the .dds on the end to find the right file so will import with .dds on the end. This is because RTW was designed to be flexible over whether there is a .dds or a .tga so it effectively looks for xxxxxx.tga and then STOPS so doesn't realise there is a dds. Max doesn't have this flexibility and so needs to be told there is a dds on the end. Thats why all the textures are named xxxxx.tga.dds not just xxxxxx.dds

What's MIP map?

[MasterOfNone]

That's right, in fact Alexander uses some RTW-named TGAs in its folder so that the tga.dds files in vanilla are not read.

[Thor the Bassist]

Just found some more info that should proberably be posted in here incase anyone else is looking for this.

1. DDS files are loaded quicker by the game and so increases load time (duh)

2. For the game to recognise a file with an alpha channel you need to put ## infront of the name. So this is what you need Sleighr but in light of the dds load time you may want to stick with dds.