View Full Version : how to make this effect

11 November 2002, 06:21 PM

let me first explain what I want. It will be an effect in an 3d animation. a devil is walking on a meadow, and while he is walking the ground under him is turning from grass to stone and water gets to lava.

now I thought I will render the environment (without the model) two times, first the grass scene, and then the stone scene.

and now my question, is it possible to animate an alpha channel from one video? I thought I just put both videos in after effects, and delete parts of the grass animation with an alpha map, so that the stone animation is visible.

is this possible? or is there an easier way?


11 November 2002, 07:47 PM
Why not try it with animated masks with a little feather?
Or you could use this vector-stuff, with animated strokes. But i think this is only available in the Production Bundle.
Not the best tips, I know, but better than nothing.

11 November 2002, 12:33 AM
or try rendering the devils shadow on a seperate pass and use that as a track matt for the ground

11 November 2002, 08:12 AM
you can just render out the alpha for teh steps (i don't know what your'e going to do to do this, possibly a proximity gradient?) anyhow put that into the layer above the layer you want to mask, then simply change the tracking matte of the layer you want masked (layer->tracking matte->whicher matte you want). that should do the trick for you.

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