Hi, I created my own explosion to see what it''d look like, rather than the default one, in NeHe''s tutorial (Lesson 32). However, I''ve spent over an hour trying to convert my animation to an appropriate format. The tutorial explains that I need to have an Alpha channel and explains (sort of) how to do it. Nonetheless, his explanation and the PSP/Photoshop help files just don''t seem to be enough. Maybe I''m just dense, but how the hell do I do it? I''d GREATLY appreciate any help someone can provide. Thanks in advance... - JS

Open your image in Photoshop. Click on the "channels" tab on the right, then "add new channel" at the bottom. Fill in white where you want the image to be opaque, and remain black where it''s fully transparent. Greyscales inbetween are translucent.

If you hold down CTRL and click on your layer (layers tab), Photoshop should select only the opaque parts of your image. You can fill this selection with white for your transparent image (in the alpha channel)

Save as TGA to preserve alpha values.

Hope I made sense...

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Hi,
I appreciate your help, but I''m gonna need more of it
I''ll do this step-by-step, so I can point out where I find trouble...
1. In Photoshop, I create a new RGB image, using ''Background Color'', Black.
2. I create whatever sprite on this surface.
3. I create a new channel on the ''Channels'' tab, using the ''Selected Areas'' option, an opacity of 0%, and the color Black. (breakpoint <-- should I select the area I want to be visible, prior to this step?
4. If no, I end up with a completely white surface. If yes, the same happens, but with an outline of what I selected prior to creating the new channel.
5. Now what? Do I select my original image (deselect the alpha)? etc.? Also, I don''t understand why it doesn''t allow me to save .tga files with Alpha Channel support. It claims that I must ''save this file as a copy''-- whatever that means?!
Obviously, I''m a newbiew to say the least, so I''m grateful for your patience. Help
- JS

Right. Well, the alpha channel is an 8-bit addition to your bitmap. It can contain values from 0 (black + transparent) to 255 (white + solid)

Create your image, on a black background if you like.

If you use more layers, select layer->merge visible so you have only one layer.

Hold CTRL and click on layer 1, this should select your image outline perfectly.

Go to channels, add a new channel (the other channels will be "eyed-out" - aka. not visible). This is the alpha channel. Keep the selection.

Fill the selection with white. Turn on the rest of the channels (RGB) so you see your image. You still have the selection.

Now you can save it as... TGA (select 32-bit), and it should work out fine.



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Man,
I''m tellin'' ya-- I swear on my grave that, although I''m following your steps WORD FOR WORD, it''s just not happening
Just curious, what version(s) of Photoshop/PSP do you use? Not that I really think it''s the problem-- guess I''m just missing something.
- JS
P.S. - The only thing keeping me from thinking my I.Q. must be in the single digits is to see how many others have had the same problem, though THEY got it... eventually

Okay,
PART of my problem is that I needed to update Photoshop to support saving Alpha channels (kinda crucial).
However, even though THAT''S taken care of, the images still load up with a background showing in Photoshop/PSP and as a plain white square in the game.
I''ve tried everything anyone''s suggested. Anyone have some other tips? I''ve about reached my limit
- JS

Yes, but do you load your TGA correctly? Have you turned blending on?

Hi,
You mean is it loaded with Alpha blending on in NeHe''s tutorial, or in Photoshop? (newbie)
- JS