Alphas: Transparent/Reflective...?

[Jehovah_of_Jive]

Greetings.

I have recently started using a newer version of DXTbmp, and can see the Alpha channel function. I'm doing a repaint of Joe Binka and Bruce Thorson's excellent PZL Wilga (most fun plane to fly since Tim "Piglet" Conrad's An-2 and Fieseler Storch!). I want to mute down the highly reflective surface. I've never done any Alpha channel work, but understand that 100% black on the Alpha is 100% transparent... or is that 100% reflective? I've read here that the lighter the gray in the Alpha, the more matt the texture. I've also read that the the Alpha channel controls the 'see-throughness' of textures. Are these statements both true? Is this not incompatible?

Thanks in advance,

J_o_J

[wji]

May I suggest (S)earching this NG over the past two-months for 'transparent' Much has been said about this before.

My installation of the latest DXTbmpx brings in a black Alpha Channel by default and each time I must replace it with a 'good' generic (trans.bmp) one  ???

[Jehovah_of_Jive]

Hi - I started by searching and found some material but am still confused, as there's some ambiguity over what constitutes 'transparent' and 'reflective'. I'm after some clarity of definition here.

From Garry J. Smith's tutorial:

"Full BLACK is the maximum reflective effect and Full WHITE is no reflective effect."

(http://www.gjsmith.net/Tutorial/step_6.htm)

From WJI's reply to Jakemaster's question about Transparency:

"Yes, all black should make it invisible."

Does 100% black do both ?

J_o_J

[igorski]

The effect alpha has is set by the modeller, so black is EITHER fully transparent, or fully reflective, but not both at once.

[Jehovah_of_Jive]

The effect alpha has is set by the modeller, so black is EITHER fully transparent, or fully reflective, but not both at once.

How/where does one set it to transparent/reflective please?

J_o_J

[igorski]

"The effect alpha has is set by the modeller"

you dont. Its a property that the guy (or gal) who made the model decides upon. So if alpha affects transparency on a model, only the person with the source files can change that as far as I know.

[Jehovah_of_Jive]

Thanks for that - not good news, eh?

Coming back to my original question - I've camo'd the plane. I want it matt(ish). Right now it's as shiny as a car in a dealer's showroom.

How can I matt it down?

Thanks,

J_o_J

[igorski]

do one thing for me, tell me what the alpha layer on Your textures is like. (check in dxtbmp or imagetool if you need)

if its all White already, then it looks like the model has 'dynamic shine' which is, again, a modeler set feature, which cant be altered by use painters.

[Jehovah_of_Jive]

It's white.

DOH! Beautifully camouflaged PZL Wilga and it shines so hard like its been polished for a concours.

J_o_J

[igorski]

Yeah, it looks like its the "dynamic shine" applied to the model. I dont like models with loads of shine, I prefer it to be left to the texture artists to add shine where needed!

[Katahu]

This is what I have learned about textures and alpha channels:

To make a texture reflective, the main texture file must contain the following suffix:

*_t.bmp

Example: Main_Texture_t.bmp

From there, you can create an alpha so that you can apply it to the main texture with DXTBmp. The darker the shade, the more reflective it is.

Now, to make textures transparent, just simply remove the suffix.

Example: Main_Texture.bmp

I learned about this very quickly when I began my first [unofficial] project of the F-117A Have Blue [the predecessor of the Night Hawk].

I hope this helps.

[igorski]

Im afraid thats a convention, rather than a set rule, texture names are purely there so that We understand whats in them!

Also, once they have been set by the modeller, they cant be changed, so do NOT change any of your texture file names!

[Katahu]

Well, you're partially correct on that one.

You're correct about the naming of the texture files. Just because a texture is named as "Reflective_Canopy.bmp" doesn't mean that the canopy will automatically reflect.

However, FS will read any suffixes appended to the texture name. For example: If I create a texture with an alpha channel, and that texture has the letter *_l.bmp appended to it [ie: Left_Wing_l.bmp], then FS will see it as a lightmap. However, I will also have to indicate that in Middleman as I export the visual model from Gmax. This will tell FS that there is a light map linked to this model.

Here is what each suffix does when appended:

*_t.bmp - A texture with this suffix will allow an alpha channel to have a reflective effect when applied. The Alpha has a transparent effect if the suffix is excluded.

*_l.bmp - A texture with this suffix will act as a light for a main texture that doesn't have this suffix. You have to link it to the main texture from within Gmax via the Material editor. No alpha is used.

*_d.bmp - A texture with this suffix will act as a damage texture for a main texture that doesn't have this suffix. The texture appears as a part that's linked to it is damaged. [ie: damage is shown as a wing is ripped off]. No alpha is used.

[igorski]

That all appears to be correct, just to clarify, these have to be set while the model is being built, you cant just come in and add a *texture*_L.bmp to a model that dosnt already have one, and expect a lightmap to appear.