Hallo people! Merry Christmas first off, haven’t been on here in a while!
Now the question: I’ve got a simple object that’s got an alpha texture on it (transparent png, it’s a cloud if that helps!). It’s animated to grow in size, but I want to also animate it so that it fades away until it’s completely gone… how would I do this? I’ve tried adding IPO drivers to the ColA and Alpha channels but no luck 
If anyone can help that’d be sweet! Cheers folks
~ Alex
Is the alpha image set up as a texture channel on a material or simply UV mapped to the object? Because I’ve had alpha images fade fine in GLSL mode when used as part of a material then using an IPO curve to change the materials alpha.
It’s set as a texture mapped with Z-Transparency onto the object. Here’s an image to show you the setup:
How did you set up your IPO?
I think I had it setup exactly as you’ve got it. I’ll double check my setup when I finish work just in case (wont be till 2am though). Does setting the alpha to 0 make the object transparent when you press P?
Nope. The alpha is set at 0 if you look at the image above (I’m assuming you mean the alpha slider underneath the RGB sliders?). It’s really confusing, it should be simple (and it probably is!) but I just can’t for the life of me figure out what’s going on.
I can drag the DVar slider down and the object will disappear, but if I set an IPO curve for DVar it doesn’t do anything…
have you set it to use OB colour
If I choose OBcolour, it will fade out perfectly but the whole texture turns black? Like it still has the alpha but turns the rest of the texture black?
EDIT: actually, it removes all the alpha info of the texture and just renders the object black but with a nice fade. WTF?
Just realised that I had this saved in my favourites:http://blenderartists.org/forum/showthread.php?t=147280&page=1
Hope this helps!
You, sir, are a lifesaver. Thanks very much!
No worries, happy I could help 