Editing Alpha Channels
with Paint Shop Pro

by toadlife - (toadlife@hotmail.com)

This tutorial was done using Paint Shop Pro 6. There is a misconception that Paint Shop Pro is not powerful enough to do advanced texturing for OFP add-ons. This couldn't be farther from the truth. Paint Shop is a powerful program that costs a fraction of what that other graphics program costs. People assume that it is only good for simple graphics editing because of what they read.

This short tutorial assumes you already know:

* How to use texview
* The basics of Paint Shop Pro and image editing in general.
* How to convert images using texview
* How to swap textures in OFP models

About TGA (.tga) files

TGA files feature a background and an alpha channel. When you open a TGA file up using PSP, the picture will appear all black. This is the "background" part of the picture. The background is all transparent, and isn't seen when being displayed in the game. The alpha channel is the part that will be shown in the game. Think of the background as being a window and the alpha channel as being paint that covers parts of the window. When you look at the window you can see through everything except the painted part.

Getting Started

Open up Paint Shop Pro and open up the TGA file that you want to change. In order to view the alpha channel, go to the "Masks" menu and select "Load from alpha channel". Once you have the Alpha Channel loaded, move to the "Selections" menu and click "Select all", then copy and "paste as new layer". This copies the current alpha channel to a new layer, which you can freely edit. If you don't do this you will only be able to edit the painted part of the alpha channel.

Editing the Alpha Channel

Now that you have an "editable" alpha channel layer, go to the "Layers" menu and delete the original alpha channel layer so that the only layer left is the new one you just created. Edit the alpha channel to your hearts desire.

Saving your new Alpha Channel and scrapping the original one

When you are done, go back to the "masks" menu and select "save to alpha channel". A window should come up which show the current alpha channel present in the image. First, you must delete the original alpha channel, and then save the one you have just edited to the image as a new one. You now have edited the alpha channel of the image. Save the TGA file. (IMPORTANT: Make sure you save the TGA file as" 24bit uncompressed" format!)

Restoring the background

The last thing you need to do is close the file and then re-open it. The image will appear white instead of black (this is the "background" I mentioned before). Fill in the whole image with black, and then save it again (IMPORTANT: Make sure you save the TGA file as" 24bit uncompressed" format!). Now your background is the same as it was before you edited it.


You now have an image that is just like the original, with your new updated alpha channel!