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View Full Version : Crawling Textures -any Answer?



Glendalough
10-21-2005, 09:44 AM
(Putting this in the Macintosh forum as more luck here with answers.)

A pity that one of the strongest points of 3D (photo-realism) becomes so terribly undermined. Beginning to feel that this dictates construction of the whole scene, -DON'T MOVE THAT CAMERA.

High anti-aliasing, a long rendering of each frame, at high resolution, like they do for films is not practical and surely no one does this for TV quality, but is this ultimately THE ONLY ANSWER?

Or does one have to blur the camera every time it moves. Maybe these things aren't as noticeable when final output is reduced to TV screen?

Just wondering if I am missing something here?

Any answers or thoughts would be very welcome.


www.theoilcans.com

andypete
10-23-2005, 10:01 PM
Try turning-off Adaptive Sampling. I just had to re-render 900 frames because a bump procedural was crawling when the camera moves.

toby
10-23-2005, 11:59 PM
Aside from turning off Adaptive, leaving Mip-mapping on high, rendering with Enhanced AA, the only option is higher AA.

You could render the object with buzzing textures separately, at high/extreme AA, or speed up the scene by giving up raytraced reflections or shadows, swap those area lights for a spinning light rig...

Glendalough
10-25-2005, 06:22 PM
Thanks for the answers......

They provided some clue what to type in for a search. Flickering is the operative word... MIP-Mapping brought up some too..

Texture filtering is what is needed (?).

This should definitely be sorted out soon....seems to be causing a lot of work...lost hours...

toby
10-26-2005, 01:12 AM
High anti-aliasing, a long rendering of each frame, at high resolution, like they do for films is not practical and surely no one does this for TV quality,

Actually, we do do this, and sometimes more. Where I work we render at enhanced extreme for the final, and sometimes even that's not enough, so we render at double size, again at enhanced extreme ( once the render is scaled back down , this is equivalent to 66 aa passes ), and sometimes with dithered motion blur. There's no such thing as fast and perfect AA with motion blur. VRay has better motion blur, but it takes just as long if not longer.
Now that I've seen the difference, I render my own projects at enh. high at the very least, and I have had a render that needed enh. extreme at double size.

How long does it take to render one of your frames at medium aa?

Matt
10-26-2005, 07:45 AM
Another way is to have a gradient on the texture tied to 'distance to camera', so when it's at a distance that causes 'crawling' you can fade it out, or lessen it's impact anyway.

Glendalough
10-26-2005, 08:01 AM
Hi Toby,
Thanks for all the info. It is pretty much as I feared. Just have to try to deal with it.

I read some article here on this Newtek site about getting away with little or no antialiasing in video which put my fears to sleep at the time. But this was probably 5 years ago and not very accurate.

My frames take 50-120 seconds to render at low AA. (But sometimes this can go up to 4 to 5 minutes with volumetrics or complex textures). The computer is an Antique G5, single processor, first issue 2003, only 1.25 GB.

I'm trying to produce short 3 to 5 minute (cartoon-like story line) animations. Beginning to wonder if this is viable...Say a month to produce 4 minutes, which gets edited to 3. A moment would be 1800 frames....this to be done -rendered- in a week. Maybe a bit of a steep order.....Wonder how much a speed increase the new Quad with 2GB would give?

Just got 14 minutes for a particularly troublesome frame at high AA (takes 50 seconds with none). A preset called "Grunge Color" was the culprit I believe.

PS -Hi Matt, Thanks for writing, Just going to try that gradiant on the texture/distance to camera idea, really interested to see how this works....

brap
10-26-2005, 10:41 AM
Don't know if you've visited the newly resurected 'flickering textures' thread on cgtalk, but lots of great tips in there to help minimize the problem:

http://forums.cgsociety.org/showthread.php?t=266264

toby
10-26-2005, 05:20 PM
hmm - 1.25 ghz is not much for rendering aniamtions. My first short film was 2 minutes and took 5 days at Enh. Low. aa, on a dual 450.

A dual-dual-core would RIP through your frames at extreme AA. Of course then you'd be tempted to do 3 bounce radiosity :D Judging by Blanos.com, it should render about 10 times faster than your machine, so your 14 min. frame would be done in 1-1/2 min., and a week-and-a-half worth of rendering in a day!

Glendalough
10-27-2005, 12:01 PM
Thanks toby for the good news about the new machines....just have to raise the money now....it would be good to use radiosity in animations but think it will be a few years yet, -or is this being tried now? Saw a toot somewhere about this...but can't remember

Hi brap, Thanks for the link to the 'flickering textures' thread on cgtalk. Glad other people are concerned about this.

There certainly is more than one facet to the problem... Really think NewTek should address this. Extra features in Lightwave are great but...

QUALITY is really everything and shouldn't be compromised. Lightwave has been pretty strong on this but what was acceptable yesterday mayn't do today...really think people should hammer away on this.