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Bjoern
October 27th, 2010, 13:59
Dangerousdave asked me about creating image transparencies in GIMP and I wrote down the most basic steps for him.
Since that information might be too important to be confined to a mere PM, here's the outlines procedure for everyone.

Layer masks basically add an alpha channel to an image or layer of an image. This saves you the tedious procedure of manually adding an alpha channel to an image with DXTBMP. Just add the masks and export the texture as 32 bit .bmp or DXT3 or DXT5 .dds and whatever you've just edited is FSX ready - straight from GIMP.


- Select transparent parts on texture
- "Layer" -> "Mask" -> "Add Layer Mask"
- Choose "Selection"
- In the window for the layers, right click on the layer with the mask and choose "Show Layer Mask"
- Edit the layer's color to control transparency (anything between black (transparent) and white (opaque))
- When done, right click the layer in the layer window again and untick "Edit Layer Mask" and "Show Layer Mask"
- If the transparency gets annoying when editing the texture, tick "Disable Layer Mask" (you can leave the mask disabled; the image will export properly)
- Export the texture in a suitable format (32 bit .bmp or, after horizontally flipping the image (CTRL+ALT+F) and with the DDS plugin installed, as .dds)
- If being asked to apply layer masks, click "yes". Only apply the mask upon exporting the image, not any sooner!

And that's it. Getting the most out of the layer masks is now up to you. ;)


- Edit:
The .dds plugin I was talking about. Read its readme!
http://code.google.com/p/gimp-dds/downloads/detail?name=gimp-dds-win32-2.0.9.zip

Bone
October 27th, 2010, 14:04
I have gimp but have never used it with flight sim paints, is there a plug-in that you need to go along with it? I have FSrepaint that I've been dabling with, but I'm having an issue with changing the alpha channel.

Dangerousdave26
October 27th, 2010, 15:49
Bone

Not if you are exporting to 32 .bmp files

If you are working on dds files then see Bjoern's post above for the plugin

@ Bjoern

Thank you

This was the part I was missing.

Bjoern
October 30th, 2010, 17:50
Note: You can't directly edit DXT'ed .bmp files in GIMP. You'll need to run them through ImageTool and save them in 32bit .bmp format first.

Bone
October 31st, 2010, 06:25
If I take the time learn a paint program for FS, I may just go ahead and get Photoshop. Sounds like GIMP needs a fair amount of converting and reconverting of paints. I'm a little put off by FSrepaint. It's easy to use, but very limited and doesn't play well with DDS textures. Also, after awhile, it starts to interfere with the way FSX runs. My fps goes to crap if I boot up my machine and use FSrepaint before running FSX...so I always have to remember to run FSX first after a reboot. Another thing is, after awhile my fps goes to crap permanently. Then I have to uninstal FSrepaint and reboot to get back my fps.

Bjoern
October 31st, 2010, 08:35
If I take the time learn a paint program for FS, I may just go ahead and get Photoshop. Sounds like GIMP needs a fair amount of converting and reconverting of paints.

Not any more or less than Photoshop. Don't be a lazy arse and waste money, get GIMP and be happy. If you don't succeed, you at least didn't spend any money.


For viewing repaints before firing up FSX, I just use MDLView or ModelConverterX.

MDLView:
http://www.sim-outhouse.com/sohforums/showthread.php?t=22896&p=483578&viewfull=1#post483578

ModelConverterX:
http://www.fsdeveloper.com/forum/showthread.php?t=14215
http://www.fsdeveloper.com/wiki/index.php?title=ModelConverterX

Bone
October 31st, 2010, 08:58
Don't be a lazy arse and waste money, get GIMP and be happy.

I've had GIMP V2.6 for awhile. I am happy, and being a lazy arse is part of my happiness and well being program!

Bjoern
December 20th, 2010, 10:19
*Bump*

Just turned this into a full blown Wiki article at FS Developer:
http://www.fsdeveloper.com/wiki/index.php?title=Transparencies_with_GIMP