Moving Shadows....Help?!!

ynotul

Hey Guys/gals.

I have this issue with where the branches/leaves on my tree have moving shadows. I'm not sure what the problem is and im wondering if any has ever has this issue.



The tree leaves/branches are made of alphas...and u also notice that the grass has moving shadows too. PLz Help!

CrazyButcher

be more specific, what software, what type of shadows do you use in that software and so on.

ynotul

My bad for providing too less info.

Um....i'm using mental ray rendering.. and I have a physical sun and sky light.
The rest is bascially most of the default settings.

rjhalvorson

ynotul wrote: »

My bad for providing too less info.

Um....i'm using mental ray rendering.. and I have a physical sun and sky light.
The rest is bascially most of the default settings.

The problem is that when using mental ray's final gather, you are probably letting it calculate the shadows after each frame. Mental won't remain consistent with the shadows over a period of time so what happens is they can swim and it will look funny.

If it's a static scene, you can check a box in the mental ray options where it will cache your final gather file and add to it during each frame. Your animation will not have that swimming effect over a period of time like you are experiencing.

The downside is that if you are animating say a character, caching his shadow file from frame to frame really doesn't work because at the end of the animation, you have shadows cached from hundreds of different poses and it won't look right.

To solve this problem, you'd have to do some compositing or using light maps for the environment, or even bake in the shadows, whatever you feel like doing.

Hope this helps.

EDIT:
I watched the video and realized it was fairly short so I'm not sure if what I mentioned will help, but if it were my project I would try that first.

ynotul

No, this is really helpful..

Do you happen to know what box I have to check off in mental ray?

ynotul

Okay, this is really getting frustrating...

I decided to do a bunch of tests with it and it still had the same problems.

So I decided to turn off Final gathering for GOOD.

For some where reason its still happening!!!!

I am totally confused as in if this can be a final gathering issue at all?

Microneezia

the video is pretty short, but it looks like you have some reflection or maybe even some refraction on the material that the shadows are casting on? Is that supposed to be water on the ground? or is there no water on the ground?

perhaps a render when the camera isn't moving will really reveal more?