#Video Post Question
3 messages in this thread
I'm wondering if this is possible to do with Video Post, and if so, how to
do it. I have an animation which takes place in front of a brick wall.
Right now, I have a wall object behind the animation with a brick texture
applied to it. The animation casts shadows upon the wall. Because of the
texture and bump map of the wall, which takes up the entire screen, it adds
quite a bit of rendering time to each frame. I'd like to use the brick
wall as a background and alpha the animation over it so it won't have to
render the wall every frame, since it doesn't change at all. The problem
is, that if I do a straight alpha, the shadows won't come out. Is there
some way to do what I want? How would I set it up in VP?
Thanks
Aaron
In a previous message I covered a technique of creating colored shadows
that might also work for this. For the full text, download the ASOFTM
message base. Although it is mainly for getting colored shadows, I'm afraid
it will not save you any time.
Basically it involves assigning everything a self-illuminating white
(255,255,255) Then render the scene, so all you have is the shadow on a
white background. These images can be used with VP to composite the shadow
back onto a scene. I don't think it will save you any time though since you
would still have to render the whole scene with a wall to get the shadows.
-MM
Hm… How about if I do this? 1) Render the animation with no background.
2) Render the shadows seperately with everything on SI white. 3) Composite
the animation over the wall, and composite the shadows on also with a gray
alpha image, so that the wall will show a little through the shadow. I
think it would work, but I don't know which way will be faster. Doing this
way, I would have to render everything twice, once for the animation and
once for the shadows. The other way, I'd have to render only once, but
wait for the wall every frame.
Aaron