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View Full Version : Distant hypervoxels too bright


thx1138
02-23-2003, 09:24 AM
Whenever I use hypervoxel volumetrics, I always run into the same problem. Everthing looks fine, except for the voxels that are furthest away from the camera. The always appear very bright, and cause teribble flickering in animation.

Here's a quick example of a fluffy cloudy nigth sky. The full moon is high on the left. The voxels in the distant middle are way to bright.

http://www.xs4all.nl/~stageri/Images/clouds.jpg

What's wrong here ? Do I need to apply some falloff ?

grtz

wgreenlee1
02-23-2003, 09:51 AM
Funny you should ask that...
I was farting around with voxels earlier tonight and I figured something out.
On those same exact voxels you have there if you increase the size they lose their density and render very white.
IF you increase the density then they come back down to the dark gray like the closer ones in the foreground like youve shown here.
If these voxels(the ones giving you problems) are farther and apart of a differant point collection or a differant emitter you can try to play with those densitys and fix it.
If they are the same emitter or point cloud then you might have to adjust an envolope or something to get them all on the same density level.
I dont know if this will work but I thought of this after noticing the same thing today.

Hope this helps.

Arte
02-23-2003, 11:32 AM
Originally posted by thx1138
Whenever I use hypervoxel volumetrics, I always run into the same problem. Everthing looks fine, except for the voxels that are furthest away from the camera. The always appear very bright, and cause teribble flickering in animation.

Here's a quick example of a fluffy cloudy nigth sky. The full moon is high on the left. The voxels in the distant middle are way to bright.

http://www.xs4all.nl/~stageri/Images/clouds.jpg

What's wrong here ? Do I need to apply some falloff ?

grtz

Firstly I wouldn't use Hypervoxels to do a scene like that. Turbulance rocks, it's even better than fractal noise.

But if you do, you can use gradients set to distance from camera to adjust just about everything in regards to colour, luminosity and most everything hypervoxel related. In fact you can even do some things you can't do with polygons like particle age.

You can also use distance dissolve or fog. Although I am not sure if distance dissolve works on Hypervoxels (never needed it.)

X

Fasty
02-24-2003, 01:33 AM
Had this problem not long ago while trying to make a row of trees. It's really frustrating and the best I could do was decrease the hypervoxels opacity, and apply a "distance to camera" gradient to darken them when they are further away. I hope Newtek fix this for the next release!

Fasty
02-24-2003, 01:34 AM
Originally posted by Arte
You can also use distance dissolve or fog. Although I am not sure if distance dissolve works on Hypervoxels (never needed it.)

X

HV's aren't affected by fog either!! :thumbsdow

phlio
02-24-2003, 05:58 PM
" HV's aren't affected by fog either!! "

I noticed this with an underwater scene I am working on... is there a way around this or should I be looking at doing something post-render? I'm still learning so I don't know much about the processes yet so any insight on solving this would be helpful. Thx!

Phlio

Fasty
02-24-2003, 09:39 PM
I'm in the same boat as you, ie still learning so my solution was to not use fog :cry: If you have any better ideas please share them! :thumbsup:

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