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yangyan
03-22-2003, 11:22 PM
Can someone tell me how to do alpha in photoshop or other programs?

Leslie Judge
03-23-2003, 07:33 AM
I tried Paint Shop Pro 7. In that I can make a mask from the actual picture or from an other one (so I can draw the mask separately if I want), then tweak it if necessary. The last step is that I save the mask to the alpha channel, then delete the mask with no merging into the picture.

When I save it as TGA, it displays a warning about only one alpha channel can be saved but that's enough. :)

lassev
03-23-2003, 08:37 AM
Aye. In PSP you can also quite easily just make a selection of the areas you want to be included and then save the selection into an alpha channel. Selections are easy to make for example with the Magic wand.

yangyan
03-24-2003, 12:46 AM
I still dont get it.

yangyan
03-24-2003, 12:47 AM
How do you save the selection in the alpha channel?

lassev
03-24-2003, 02:40 AM
In Paint Shop Pro, just do your selections, then go to the Selections menu and choose save to alpha channel. However, there's one catch in this business: if you are making, let's say a grate, what part of the picture do you save to the alpha channel? The grate itself or the black area, where you should see through the grate?

I have done different grates, glass with some non-transparent markings, and some other shaders with transparent areas, but still I don't automatically remember this... Eh, so I don't remember, before I have a look at some .tga I did before (or some Raven one). Luckily, you only have two choises. And no doubt somebody will post here the correct answer.

And remember it has to be a targa file. JPEGs never have but one layer, no alpha channels.

Leslie Judge
03-24-2003, 11:32 AM
:) It doesn't matter what part do you select, the grate or the gaps. You can use either, just need to modify the shader code properly. :)