View Full Version : Can alpha mapping be selective ?

09-03-2004, 09:10 AM
A strange question I think so I should explain :)

Imagine a scene where you have just a car and nothing else.
Lets say it is viewed from above to keep things simple.

I make a render and save it as TGA to preserve the alpha map.
In the image viewer, if I selct Alpha map, I am shown the alpha map of that render which in this case is the outline of the car.

Now... I add a floor object.... and re-render. Because there is a floor which takes up the whole camera shot the alpha image is now all one colour and no more car outline.

So what I want to know is, can I tell LW somehow not to take the floor into account when generating the alpha map ? So I can still get that alpha map showing the outline of the car even if I have a floor there ?

09-03-2004, 10:12 AM
On a per Object basis:
Object Properties -> Render -> Alpha Channel
Or, per surface:
Surface Editor -> Advanced -> Alpha Channel

Mike - and no RTFPDF ;)

09-04-2004, 09:04 AM
Thanks Mike,

That PDF arghh :) Yeah I know I should read it but sometimes its a pain trying to find the exact thing you want to acheive. It can be quicker asking on a forum even though thats not a good example to set :)

Im still trying to figure out how to print it.
My deskjet will melt and our office colour laser will take ages.
Printing company will charge a fortune too so I hope Newtek will make a printable version on its own that we can buy.

Anyway thanks again. I will read before asking next time I promise.

09-04-2004, 09:06 AM
See, if there was a decent manual I'd have RTFM'ed you, but since I hate reading PDFs as well ... ;)