Alpha Channel

[Batman93210]

I'm doing a repaint, but the finish is dull. I have figured out how to make the wings chrome, by creating an alpha channel (black). Thats ok for the wings, but how do I get a semi'gloss finsh on the rest of the plane

[|| Andy ||]

You need to imagine the fuse on the alphachannel..
better still...
Open the alphachannel in the editor, and then make it so you have a outline of the fuse and wings, then colour in the bits you want in the right colour.

Remember to have the alpha the same size as the fuse when ure editing, then resize it to 256x256...

Regards,
Andrew Stokes
http://andrews.f2g.net

[Stratobat]

Hi Batman, Try this out

Take the 24 Bit texture that you've repainted, make a copy of it and open the copy in PSP. Convert that texture to a Greyscale and Save (This texture is now your Alpha Channel). Now paint the various parts on the Alpha Channel using progressively lighter or darker shades of Grey until you think it looks right (The lighter the Grey, the more opaque the texture will be, and visa-versa). Now using DXTBmp combine the Alpha Channel with the 24 Bit texture (Backup these files just incase you need to edit them later) and save in the format your using for the textures (32 Bit, DXT3... etc). Pop the Texture into the Aircraft's Texture folder and fire up FS. If the texture still has to much shine, open the Alpha Channel bitmap again and make the Grey a little lighter. You will probably have to edit the Alpha a few times before you get it right.

Don't worry about reducing the Alpha to 256x256, as it's not necessary!

Regards,
Stratobat

[Batman93210]

Thank you for your help  :)

One question:   what is PSP?

[Stratobat]

PSP = Paint Shop Pro

Regards,
Stratobat

[Batman93210]

Will Pixia work? I dont have Paint shop pro.

[Felix/FFDS]

Yes, pixia works fine for this purpose

[Stratobat]

Should work, but I don't think Pixia converts to Greyscale

Regards,
Stratobat

[|| Andy ||]

I always thought u had to reduce it to 256..
Is that just for performance..
All the alphas ive looked at are in psp..

[Stratobat]

I always thought u had to reduce it to 256..
Is that just for performance..

I don't think there is any performance gain

I normally leave then the same size as the repainted texture

Regards,
Stratobat

[Batman93210]

Stratobat , thank you for your help I finally got it.

Now can I manually paint the  greyscale on to the alpha? I downloaded a fee trial of PSP, but at a $100.00  I cant by it. I have Paxia, and MS Paint, but I gess that thay cant convert  to a greyscale. Well thanks for the help agen

[Stratobat]

Hi Batman,

Now can I manually paint the  greyscale on to the alpha?

The Greyscale image IS the Alpha

I have Paxia, and MS Paint, but I gess that thay cant convert  to a greyscale. Well thanks for the help agen

Either I'm just blind, or there isn't a Greyscale option in Pixia, but I think I have a workaround for it..

You'll need Pixia (With optional Plugins and Filters found on the Pixia Website installed), MS Paint, DXTBmp and Imagetool.

Take the repainted texture and back it up. Name this backup texture Tex_Backup or something like that. Take the Tex_Backup bitmap and open it in Pixia (Make sure it's 24 Bit and not 32 Bit - Pixia doesn't like 32 Bit). Once in Pixia, look for the Filter Icon (Red & Blue Circle icon in top right corner), press it and look through the Effects for Monotone. Select Monotone and press Execute. A little box will open up giving you a few options, select Black & White. This will convert your colour repainted texture into shades of Grey ranging from Pure White to Pure Black. Save the texture as Tex_Alpha or something like that. Now, take the Tex_Alpha bitmap and open it in Imagetool. Convert the texture into an 8 Bit image (Image... Format... 8 Bit). Now, open the texture in MS Paint and edit the bitmap using various shades of Grey until you think it looks right. Remember, the more White the texture, the more opaque the Alpha will be in the Sim. So Anti-Glare panels, wheels and bit's and pieces that you don't want to be shiny must be painted White or lighter shades of Grey on the Alpha bitmap. Once you have edited the Tex_Alpha bitmap and are satisfied with your work, open the REPAINTED texture in DXTBmp and import the Tex_Alpha bitmap using the Import Alpha Channel option (Alpha... Import Alpha Channel). Once the Alpha's imported, you should be able to see it displayed in the top right-hand box in DXTBmp. Click on Apply Alpha to Image (Alpha... Apply Alpha to Image), untick the Mip Maps - Include When Saving option located below the Alpha Preview window. Now save the texture in whatever format you choose (32 Bit, DXT... etc) and drop it into the Aircraft's Texture Folder.

That's it... You should now be able to see your repainted texture with the custom Alpha Channel in Flight Sim

I tried this method above on a repaint I did of a P-51H Mustang and it seemed to worked, but you might need to experiment with it... Just remember to make backup copies of your repainted texture in another folder on your PC so that if it doesn't work, you still have your repaint

You can always use the Alpha Channel bitmap that comes with the original aircraft, but most people just overpaint the whole bitmap with one shade of grey, so if you want to add details or more/less shine to certain areas, it can be a problem

Regards,
Stratobat

[Batman93210]

Stratobat , Thank you for your time, and help

I understand what you are saying. I downloaded a 90 day free trial of PSP, and I have learned in the past few days working on this repaint how to edit the alpha with yours, and the other folks that have helped me.

I am still learnning about the alpha channel. I understand that the alpha controls how much the finish will shine. So white would be a flat finish, and black would give the airplane a  chrome finish. So depending on the degree of shine you want one would have to work between  white being a flat finsh, gray, and black being chrome. So my question is. Is this all the alpha controls?

[Stratobat]

So my question is. Is this all the alpha controls?

Yip, the Alpha basically controls the shine on reflective textures. Alpha's can also render parts of a 3D model transparent if you paint the area on the textures Pure Black or Pure Green. So for example, if you had a Mirage F1 but wanted to do a repaint of one that didn't have an external In-Flight Refuelling Probe, you would paint over the probe using Pure Green and then tell DXTBmp to give the texture a Pure Green Alpha Channel. This part would now be rendered invisible in FS. The only drawback here is that you would still see the IFR Probe on the ground shadow cast by the aircraft

Regards,
Stratobat

[Batman93210]

Ok, I figured that out by when in doubt click it