ADOBE AFTER EFFECTS 83 PRECOMPOSE
From: pkmayavi (pkmayavi@no-spam)
Subject: Precompose
Date: Wed, 30 Jul 2003 20:26:03 -0700


Hi,
Can any one please explain me what is precompose all about. What is the use of it.

Thanks






















From: smulli (steven@no-spam)
Subject: Re: Precompose
Date: Thu, 31 Jul 2003 01:19:28 -0700

Say you have an position-keyframed animation of a butterfly hovering. Say you want a bunch of butterflies hovering, you duplicate the original 9 times. Now you've got 10 butterflies hovering.


Now, what if you wanted the 10 hovering butterflies to move around as a group. You could either go in manually and keyframe all ten butterflies hovering and moving, or you could precompose the ten layers into one layer, and keyframe that one layer's position. For that matter, you could also make the group of butterflies fade away, or turn blue, with one action, instead of ten.


Pre-composing is typically a time-saving way to make blanket changes to a group of layers.



From: pkmayavi (pkmayavi@no-spam)
Subject: Re: Precompose
Date: Thu, 31 Jul 2003 03:27:49 -0700

Thanks smulli .Now i got some idea regarding precompose.The help files were of no help.I read them several times, but there were no examples. But now my doubts were clesr to a great extent. I don't undersyand why the adobe help does not contain any examples.

Any way thanks again

From: "Navarro Parker" (nparker@no-spam)
Subject: Re: Precompose
Date: Thu, 31 Jul 2003 05:38:59 -0700

You also need to pre-compose for some effects that can't go beyond the edges of it's source dimensions. And you usually have to pre-compose any Illustrator layer that's continually raterized and has an effect applied (although that will change with AE 6 - yea!)



From: "Brad Gayo" (brad_gayo@no-spam)
Subject: Re: Precompose
Date: Thu, 31 Jul 2003 06:51:53 -0700

Precomposing also helps to alleviate the final render time for a project. More effects stacked up in nested comps after nested comps with heavy keyframing all translates into render time. Navarro makes a excellent point as well in consideration of boundary limits.



From: "Aaron Cobb" (gromit59@no-spam)
Subject: Re: Precompose
Date: Thu, 31 Jul 2003 06:59:16 -0700

Precomposing also allows you to manipulate the render pipeline. Assuming you don't collapse transformations on the nested comp, everything inside is rendered into a single layer before it it composited in the containing comp. This can radically change the way transfer modes operate.


Furthermore, effects that use layer maps (such as Particle Playground, Displacement Map, etc.) ignore effects, masks and such due to the order of the render pipeline. Precomposing and moving all attributes into the new comp forces those effects and masks to be applied before the layer map is evaluated.


Aaron

From: pkmayavi (pkmayavi@no-spam)
Subject: Re: Precompose
Date: Thu, 31 Jul 2003 20:19:24 -0700

Thanks every one for their expert guidances.