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jetstreamsky
February 13th, 2010, 11:17
Hi,

I could do with some pointers with the alpha used to control shine on an aircraft repaint

I'm using a paint that supplies an alpha layer, so I start with that and placed some boxes of various shades between white and black to see what the impact is in FSX, but I'm not seeing any change in the result in FSX.

When I use DXTBmp and import the alpha .bmp, I can see in the preview window that my changes aren't there. However open the same file with IrfanView and I see my changes?????????????

So I've tried converting to greyscale before saving the .bmp and importing again, but still no change.

My changes simply don't get included for some bizarre reason.

I've run out of ideas what to do, so all help is gratefully received

Thanks

Allan

http://i198.photobucket.com/albums/aa147/Jetstreamsky/FSX/alpha0.jpg
Paint kit default

http://i198.photobucket.com/albums/aa147/Jetstreamsky/FSX/alpha2.jpg
My trial version

http://i198.photobucket.com/albums/aa147/Jetstreamsky/FSX/alpha1.jpg
what I see with DXTBmp

fsafranek
February 13th, 2010, 11:47
Well, the way I always do it is this...

First I paint the texture normally (I still use PSP7 after all these years) and save "a copy" as BMP.

Then I make another layer where I put the various Alpha information. Black will give me a chrome finish (or make a hole depending on how the model was built to deal with alpha layers) and white will do nothing. Various levels of gray in between will give me varying amounts of reflection or opacity, again depending on how the model was built to deal with alpha layers. I save the PSP file again and then save a separate copy as BMP and include "alpha" in the name (you can name it anything just so you can find it later).

Then in DXTBmp I open the regular texture BMP that I made. Then in the upper right corner I click the left icon with the tool tip of "Import Alpha Channel". After I locate and click OK the BMP file I saved of the alpha channel then appears there.

To save this combination in the right format for FS2004 I select File -> Save As ->Extended Format -> DXT3. The resulting BMP file is then placed in the appropriate texture folder of the aircraft in FS2004 and I'm finished.

If this is for use in FSX I take that BMP and run it through ImageTool that comes with the FSX SDK to make the DDS format texture file.

There is another method so that the alpha channel is not handled as a separate file for processing. You can find a description of that here: http://www.calclassic.com/repaint4.htm I've done it this way as well (following Tom's tutorial) but I'm just used to doing it the way I described above.

Hope this helps.

:ernae:

YQTFun
February 13th, 2010, 17:33
After you import the alpha in DXTBmp do you "refresh alpha"?

jetstreamsky
February 13th, 2010, 18:58
Well OK, it's me :redf:, although I was writing the alpha to the correct directory and I was viewing it from the correct directory, when I called it into DXTBmp, it was defaulting to a different directory even though it looked in the correct directory for the main image.

Thanks for your suggestions anyway.