[FUBAR-BDHR]

Recently doing some nameplates for TBP I was saving shine maps in DXT5 resulting in some rather shiny ships.  After scratching my head I accidentally hit on the problem.  The original shine maps were saved in DXT1 format (verified by looking at the DDS file header).  Everything I've read and been told seems to point that DXT1 can't be used for shine maps.  So now I'm wondering if the shine maps are even doing anything or does DXT1 work for shine maps? 

[Water]

The alpha for a DXT1  pixel is either black or white, no greyscale. So a DXT1 shine map will work fine.

Black alpha = no Environmental mapping

Edit: Changed No to Black

[Vasudan Admiral]

Don't mistake shinyness for reflectivity - DXT1 shine maps will more than likely have have the Alpha pixel Water talks about set to white, resulting in the effect where your ship is 100% reflective in-game, but with normal shine. Test it in the ship lab if you're unsure by seeing if the look changes when env map is turned on or off.

[Scooby_Doo]

If I'm not mistaken, no alpha = complete environ mapping

[DaBrain]

DXT1 supports an 1-bit alpha channel. So just make it black and the env mapping will be gone.

Or alter the shaders so it uses another color channel for the env mapping.

I am not 100% sure if FS2 supports the 1-bit alpha channel.

[FUBAR-BDHR]

Well that's good to know at least DXT1 does do something.  I thought they were doing something but was worried they weren't.  Actually my big fear was that they were all saved incorrectly but thankfully that's not the case. 

I've been using paint.net (yea I know but it works for what I do) and I don't know what the option does but weight color by alpha and DXT1 is what seems to give the same effect as the originals.  What that flag does I have no idea.

[Nuke]

1 bit alpha only gives you full env or no env. but at least it lets you pick one or the other. dxt1 should default to no env, but if you get excessive shinys then it defaults to full env. what we really need is a materials system.

[chief1983]

If you tell me which maps need it, I can probably get some DXT5 maps with proper env to them, that aren't mirrors but still offer a bit of a sheen.  Needs a slight reflection, they're mostly metal after all.

[redsniper]

Herra says they should be concrete...

[blowfish]

FS2 will not read DXT1's alpha channel.  When DXT 1 is used (or any format that lacks an alpha channel, for that matter), environmental mapping will be calculated based on the RGB intensity.  For format's like DXT3 and DXT5 which have an alpha channel, that alpha channel will be used.  So if you leave the image fully opaque and save as DXT5, you will get full alpha.

[Herra Tohtori]

Herra says they should be concrete...

Oh what a funny man you are...

I was talking of the basic underlying structure of something like GTD Orion, not the surface of the ship. Reinforced concrete might not be as silly a building material for a massive space ship as you might think. Provided you can use it where you're building the ship. Using it in vacuum might be slightly problematic.

Regarding DXT1; I was under the impression that FS2_Open does not even read the alpha channel on that format, and when there is no alpha, the engine currently interprets it as black (no alpha). Am I completely in the woods with this assumption of mine?