Using separate images for alpha channel?

Hello, I was just wondering if someone could point me in the direction part a shader(particles/additive) that uses a separate texture for the alpha channel.

If anyone can assist me on this it would be great.

Cheers

Putting a compressed RGB mask into the alpha channel looks awesome.

http://www.imgtec.com/forum/forum_posts.asp?TID=1771&PID=5717&SID=a225e63272zd61a3fac9af159b7528fc#5717

I am very slow when it comes to shades, what exactly is this bit of code you posted on “Imagination”?

I am scrolling the texture so I can’t use a normal alpha channel. Or that will scroll as well.

Cheers