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smurfted
04-07-2008, 10:52 PM
So i stumbled on a problem recently, i'm working on a big project and have also recently taken to rendering in layers (as the whole thing renders quicker, more control in editing and quick re-render of mistakes/changes).

So now i render out certain files with an alpha chanel in the file, great.

But i've stumbled on a problem. If i have an object in the fore ground of the scene, the object i'm rendering should be able to dissappear behind it..

So does anyone know of a way of making a negative alpha map object???

AAAron
04-07-2008, 11:06 PM
You can play around with object buffer passes or use the matte object function, both ways of working includes using the compositing tag.

Object buffers works like alphas but only the objects with a comp tag using the corresponding buffer id will show up in the "alpha"/buffer pass, however stuff (with another buffer id nr.) in front of the objects will be rendered black in the bufferpass covering them.

smurfted
04-07-2008, 11:30 PM
That is a good idea.

Though i have been rendering a quicktime file with the alpha embedded, and my scene is getting really hectic, so going through and altering lots of composite tags could prove costly at rendertime if i forget any..

Let me see if i group things in a way that they can fall under 1 composite tag..

smurfted
04-08-2008, 12:13 AM
As i'm using GI some (well a lot) of the objects have their own comp tags (to remove them from the gi calculations and various other things), these overwrite that info from the parents comp tags..

Hmmmmm....

bobzilla
04-08-2008, 12:34 AM
I have nothing to add but to say, Mike, you have the best thread titles!!

smurfted
04-08-2008, 11:22 AM
Thankyou :)

However my problem is still irritated and painful to the touch :(

WillBellJr
04-08-2008, 05:15 PM
Between the title and that previous comment, I have to admit, I've suffered a really good chuckle out of this thread! ;)

-Will

Kai001
04-08-2008, 06:48 PM
For compositing layers into a finished video I'd reccomend software like Adobe Premiere, or Adobe After Effects. Render all your layers as multipasses to seperate image sequences and compile them in your video editor. This will also give you more control over post effects as you can add others later in the video editor.

Hope this helps,
Kai ;)

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04-08-2008, 06:48 PM
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