fri 18 sep 1992 12:00:00 salem, ma
notes for "egg"
[these are some notes i made to the people who were designing what would ultimately become "aftereffects" -- sgc]
here are some of my random thoughts about egg as i have seen it today.
basically i think the things i need to do most often should be made the easiest to do, instead of being workarounds.
again, the paradigm that seems sensible to me goes like this. see if you think it may be somehow compatible.
at any given layer, i am performing some action to the composite. this action may be that i am pasting a new image, or that i am performing an effect — or both. but not necessarily both!
in either case, the “selection” area to which the action is performed must not be arbitrarily chosen. i need to choose it myself. too bad premiere didn't realize that! the matte should, just like the images, be choosable from among quicktime, pict or pics files, or — now that i realize it's possible — another comp! what this means, however, is that every layer may require both an image and a matte.
“use matte” may be an optional thing of course. or maybe matte is a property of every action layer, and by default it is fullscreen 100% white. but i need to be able to call any file i want as a matte.
most often the matte will be the alpha channel of the image i am pasting. other times it will be an independent grayscale pict file — and fairly often it will be another comp that i have created with egg. unless of course i'm dreaming and this isn't really possible. i'm only looking at it from a user's point of view. if i could sum my mattes in a different comp, then use that comp as a selection area for my next action, that would make me happy.
it would be a shame if, when i go to paste an image on a given layer, it were automatically pasted only within the alpha channel of that image. that would dramatically increase the time i spend “off-offline” trying to make sure the right matte is in the right alpha channel.
in our example of the cat superimposed over the plaster wall, for example, you mentioned that i could simply put the plaster wall in again and use the matte selection to darken the shadow area. but under the current circumstance i would need to make sure the shadow-cat-shape was already in the alpha channel of the picture of the plaster wall — which is not bloody likely. see what i mean?