PDA

View Full Version : LW 9 Is flickering textures finally going to be solved?


Ken Mac
08-10-2005, 02:06 AM
So is LW 9 finally going to solve the flickering texture problem?
God I hope so.

duke
08-10-2005, 02:44 AM
What flickering textures?

brap
08-10-2005, 03:01 AM
I don't know, but the fact that Mark Granger is in charge of the renderer now I think bodes well for that little 'ol problem. Texture filtering and AA in EI Camera was always quite good, and I'll bet that he won't be satisfied with the current LW status quo.

Chaz
08-10-2005, 07:29 AM
I posted in regards to this subject here (http://vbulletin.newtek.com/showthread.php?t=39283)but haven't gotten any response from Newtek.

Ken Mac
08-10-2005, 11:53 AM
I hve found this issue to be a major problem for many folks who create architectural animations.

Let's keep our fingers crossed.

Julez4001
08-10-2005, 12:34 PM
Same here in my character animation....

Its a dead horse that needs to be beaten.

Hoopti
08-10-2005, 03:31 PM
I thought this was an issue with using .tiff fiiles in the texturing, but I also thought that if you used another type of file that the flickering went away. Is that not the case?Hoop

Chaz
08-10-2005, 05:38 PM
No, it happens with pretty much every file format I've ever used. There are ways around it, such as rendering at a slightly larger image size and saling down, but Newtek really needs to address the filtering issues.

Ken Mac
08-10-2005, 05:49 PM
No, it happens with pretty much every file format I've ever used. There are ways around it, such as rendering at a slightly larger image size and saling down, but Newtek really needs to address the filtering issues.

Much Agreed!!

Ken Mac
08-12-2005, 12:24 AM
bump........

StevenDS
08-12-2005, 02:21 AM
Are you network rendering?

I understand that network rendering can cause flickering textures because of different CPUs that may be used in network rendering.
I think I heard the problem was most pronounced when using say, Intel AND AMD CPUs in render farms, and sometimes even when using different Intel CPUs of different sorts (P4s and P3s, or even different AMD CPU generations mixed, etc). I think it had to do with different random number generators in CPUs. I could very well be wrong.

If you are using only one CPU and are getting flickering, then, um, never mind.
-S

c-g
08-12-2005, 02:37 AM
Are you network rendering?

I understand that network rendering can cause flickering textures because of different CPUs that may be used in network rendering.
I think I heard the problem was most pronounced when using say, Intel AND AMD CPUs in render farms, and sometimes even when using different Intel CPUs of different sorts (P4s and P3s, or even different AMD CPU generations mixed, etc). I think it had to do with different random number generators in CPUs. I could very well be wrong.


You are correct....if you said that about eight years ago and it was a procedural texture that you were rendering. Now there are many mixed farms out there now and image maps aren't generated at render time like procedurals. That math should be fixed AND this was never an issue with image maps.

Chaz
08-12-2005, 04:00 AM
If you are using only one CPU and are getting flickering, then, um, never mind.

This is for all CPUs, be in a renderfarm render or off your workstation. Check out this link (http://www.td-grafik.de/softw/lightman.php?lang=en#why) for an idea of what we're talking about. Lightwave's texture filtering causes shimmering.

StevenDS
08-12-2005, 04:06 AM
WOW.
I see what you mean.
I'm just a hobbyist(sp?) so I guess I haven't run into that.
Yet.
And I hope I never do and I hope that LW9 changes that.

Seriously.

-S

Ken Mac
08-12-2005, 11:45 AM
No render farm needed for this issue.

BazC
08-12-2005, 11:56 AM
I'm not sure if this is the same issue but the Andy Bishop video here (http://www.newtek.com/shows/siggraph/2005/2005.php) says that the jumping and shimmering issues in LW animations have been fixed in LW9.

Emmanuel
08-12-2005, 01:30 PM
THAT was about the jumping and vibrating of the dynamics simulations (objects are vibrating when they actually should come to rest).

BazC
08-12-2005, 01:34 PM
Ah OK! Thanks for explaining! :o)

Ken Mac
08-13-2005, 12:15 AM
I wrote the following to NewTek...

Hello,
I was wondering if LW 9 has solved the problem with flickering textures.
There are many of us who are keeping our fingers crossed.

Here is what tech support said...

Once LW9 is closer to release and there are more development notes regarding fixes as well as features, more info will be posted on the website.


I would gather by this reply that as of now it still remains a problem.....

RobertoOrtiz
08-13-2005, 12:19 AM
Which makes me say again...

WHAT PROBLEM?
-R

Jarrede
08-13-2005, 01:56 AM
I posted a topic a few days ago regarding LW chattering in general, and things that may cause it. There are a host of issues that can cause a "flicker" effect in the final render.

Unless you guys are talking about something completly different. It's not always an issue of texture maps, so if yall run into it, don't assume it's your textures right off the bat.

I've spent about the past month fixing "flickering" issues in multiple scenes, and wish the problem opon nobody, so please keep in mind my findings and add to them if I've missed anything.

Chewey
08-13-2005, 03:33 AM
This complaint tends to be part of what can be termed "freshman" syndrome. Flickering textures can be experienced even within Pixar's Renderman if you don't understand what you can and can't do.

Jarrede
08-13-2005, 04:41 AM
This complaint tends to be part of what can be termed "freshman" syndrome. Flickering textures can be experienced even within Pixar's Renderman if you don't understand what you can and can't do.

yeah it's an issue that can exist in most renderers to my knowledge.

ThE_JacO
08-13-2005, 05:18 AM
textures flickering is indeed a problem that can occour in ANY rendering engine, and it's usually an issue during the sampling process.

sampling a pixel heavy texture that takes a small region of the cameraSpace (such as a large texture on a small grid, or one on a slanted grid representing a ground) can result in samples that largely differ at different frames.

the solution is usually some form of supersampling for the cameraSpace (high AA) or some form of mipmapping and/or filtering for the texture.

if it's true that blaming it on the engine alone IS a bit of a freshman syndrome, saying that it happens in all rendering engines (especially calling in cause PRMan that deals with this in an excellent manner) with the same frequency is a clear sign of "app fedayin" syndrome, and it denotes a clear ignorance of the other terms involved in the comparison.
it's a good line of action, when in doubt, trying to avoid making statments about something you only understand halfway through, and not fully.

other rendering engines have mechanisms in place to prevent this from happening or to reduce the problem and automate the process, such as eliptical filtering, automatic mipmapping, automatic discretization of the texels in UVspace with consequent adaptive mipmapping, aliasing analisys of the texels etc.

Such mechanisms are simply NOT present (or not exposed and not up to par) in LW's engine in its current incarnation, so it's perfectly legit that some people would like to see a solution to them, even if they are not rendering savy enough to know exactly where it comes from.
If LW had a good filtering subset of tools in place to deal with this then you could call people on their ignorance of the process and point them to the solution, however, as this is not the case, saying it's totally down to the users is a bit on the insulting side.

Just for the record, here we mostly use 3DeLight (a RMan interface compliant engine) and we NEVER had a flickering texture, even when a character with 64 textures and a large 16k texture on it was only taking a small area of the camera space.

duke
08-13-2005, 06:35 AM
What Jaco said. It occurs when you're trying to fit fine detail onto a small space from that camera positions/angle/zoom, so if a 1024x1024 texture is only taking up 100x100 of screenspace, it needs to work out which pixels to choose to represent that 100x100. High AA can fix this to some degree as it has more samples to choose from in determining which is the better pixel value. Even though LW's implementation of texture sampling isn't up to scratch with some other renderers, I strongly suggest you play with the texture AA/mip level (default is 1.0) if using textures. If you're using a very fine procedural you are going to get the same issue, and the only thing you can do here is to alpha it out using a distance to camera gradient.

Jarrede
08-13-2005, 09:03 AM
"saying it's totally down to the users is a bit on the insulting side."

there are ways it can be avoided/minimalized in LW, if your aware of all the elements that can contribute to it, and it ain't just images! :P

my topic was to help those that are unaware so they can be prepared, not to insult.

I can honesty care less about the software mechanics that causes it, I know it's there, I know ways of fixing/minimalizing it, and I've offered some solutions.

ThE_JacO
08-13-2005, 09:13 AM
there are ways it can be avoided/minimalized in LW, if your aware of all the elements that can contribute to it, and it ain't just images! :P


as the topic was flickering -textures- that is what I was addressing.
if the topic becomes flickering in general the scope is a lot wider and there's thick rendering books that deal with it, in one form or another, in half the pages.


my topic was to help those that are unaware so they can be prepared, not to insult.


I wasn't really addressing you to be honest, it was chewey comment that I found a bit slanted, as it only called on people ignorance without explaining what these miraculous solutions were or when he saw it not being addressable in PRMan the last time.


I can honesty care less about the software mechanics that causes it, I know it's there, I know ways of fixing/minimalizing it, and I've offered some solutions.

if you understand the mechanics you know what causes it and how to solve it in some way, implicitly :)
rendering theory is worth giving a shot even if you don't intend starting to write your own shaders in the near future. I'm digressing here though.

Jarrede
08-13-2005, 09:27 AM
if you understand the mechanics you know what causes it and how to solve it in some way, implicitly :)
rendering theory is worth giving a shot even if you don't intend starting to write your own shaders in the near future. I'm digressing here though.

I hear where you commin from, and most the time it's true, although when software isn't doing what it could, or is supposed to do, since I'm not a programmer the solution usually consists of workarounds/sacrifices.

really the only advantage I can see in knowing what's under the hood is being able to identify what the exact problem is in most cases...

Kinda like, I know Volumetric's won't render with multiple threads enabled. I have a pretty good idea why, but it's not really gonna help me any...

only reason I mentioned it may not be images is...if someone can't identify the problem areas, they may assume it's a problem with there images, spend hours trying to fix it, only to realize later that reflection channels are the main problem.

Just wanted to make it clear to everyone before they started messin with their image maps. :)

Ken Mac
08-13-2005, 11:17 AM
Flickering textures...That is the issue.
As a freshman I know all the work arounds and as a professional who owns and runs his own company texture flickering is a real problem. It takes time to tweek, takes time to do test renders and basically costs money having to deal with.
LW has BIG problems when it comes to this.

But anyway, why would a freshman care about such things ????

Jarrede
08-13-2005, 01:17 PM
everyone should care about flickering problems...

I don't have issues with flickering image maps as much as I do with other things that cause the same effect. :)

Chewey
08-13-2005, 03:14 PM
as the topic was flickering -textures- that is what I was addressing.
if the topic becomes flickering in general the scope is a lot wider and there's thick rendering books that deal with it, in one form or another, in half the pages.



I wasn't really addressing you to be honest, it was chewey comment that I found a bit slanted, as it only called on people ignorance without explaining what these miraculous solutions were or when he saw it not being addressable in PRMan the last time.



if you understand the mechanics you know what causes it and how to solve it in some way, implicitly :)
rendering theory is worth giving a shot even if you don't intend starting to write your own shaders in the near future. I'm digressing here though.

Please refrain from that style of finger pointing and mischaracterization. It really is unecessarily argumentative.

Chaz
08-14-2005, 06:08 PM
Which makes me say again...

WHAT PROBLEM?
-R

Check out the Dune miniseries on DVD. You'll see tons of shimmering, espcially in the desert scenes.

I think Jac-o is absolutely right; while there may be workarounds in Lightwave's render engine, other packages out of the box (such as XSI) do not exhibit this phenomenon anywhere near as badly, if at all. This is not about bashing Lightwave, it'd be nice to see the problem fixed.

And Chewey, referring to this as a "freshman" problem is a little insulting.

RobertoOrtiz
08-14-2005, 07:26 PM
Chaz, thanks for making a good argument.

And to the others,
please lets not make it personal. If it does I will close the thread.
-R

Chewey
08-14-2005, 10:33 PM
Chaz, thanks for making a good argument.

And to the others,
please lets not make it personal. If it does I will close the thread.
-R
Thanks Robert. Apparently some seem inclined to put a pejorative spin on a straighforward comment/observation and make a mountain out of a molehill.

dmaas
08-15-2005, 02:32 AM
There are a couple of different things that can cause "flickering..."

First, Lightwave's procedural textures sometimes don't anti-alias well. These are not a big deal because you can usually get rid of the flickering by carefully fading down the texture or upping the number of AA passes.

Second, not using mip-mapping ("Texture anti-aliasing") will cause flicker. Always turn this on. Except, Lightwave has (had? - I haven't checked lately) a bug where if you enable mip-mapping, pixels "leak" from one edge of the texture to the other, even if the edge mode is set to "clamp" instead of "repeat". This means you either have to disable mip-mapping or make your texture slightly larger than necessary.

Also, Lightwave has (had?) a bug where it reduces the mip-map texture filter size when you increase the number of AA passes. This is wrong because the correct filter size depends only on the final output resolution, not the number of AA samples. You can work around this by upping the mip-map blur value, although your one-pass preview renders will then look very blurry.

Finally, Lightwave's uniform pattern of AA samples always causes stair-stepping on diagonal edges. The new pixel filter options help somewhat, but do not eliminate the artifact entirely. I think it will be another version or two before they fix this. In the meantime, I usually render Lightwave elements at twice the output resolution, then scale down. That gets rid of the stair-stepping (although render time is obviously affected!)

RobertoOrtiz
08-15-2005, 06:35 PM
So Dan, would you have do you have a list of recomendations to improve the renderer?


-R

brap
08-15-2005, 07:07 PM
I've found my biggest flickering problems have come from using procedural bump maps, and particluarly when using multiple layers of procedurals. It helps a great deal to bake them out, but that obviously can make multiple revision tweaking a little more time-consuming. I'd love to see improved procedural AA in LW9.

-Jamie

Freak
08-15-2005, 10:27 PM
I've found my biggest flickering problems have come from using procedural bump maps, and particluarly when using multiple layers of procedurals. It helps a great deal to bake them out, but that obviously can make multiple revision tweaking a little more time-consuming. I'd love to see improved procedural AA in LW9.

-Jamie

I Agree with the Bump map, thing.. and what Dan mentioned....

However, the only time i have heard of this is from Procedurals...
And their are work arounds.. If anybody has some screenshots,
or video footage of the problem, i'd love see actual detail of the problem....
(in a scene file would be good)

Are we talking pop crawl? (i imagine so)

Aliasing problems on Procedurals, are a downside of procedurals,
not with LW..... This happens to some extent on every engine..
(including Renderman) I find that the MipMap fixes, cause over AA'd lines...

Lightwaves Procedurals have no built in AA sampling methods...
Therefore can cause flickering, when animated...
It can be managed, but not eliminated..

Other sampling, AA and Filtering or prefiltering, methods
can be implemented...... But at the cost of the procdural
quality and rendertimes..... (i'd rather the quality and speed)

ThE_JacO
08-16-2005, 04:31 AM
shimmering and popping bumpmaps DO NOT share the same solution texture filtering for shading does.

while flickering of textures can be solved by filtering, so that the filter will work out in a smart way how to mix, fade and cull data in the texture to prevent flickering, bumpmaps do NOT benefit from that.

bumpmaps work by normal perturbation.
this means that once the engine has sorted out the geometry, it proceeds to assign texels, aka the pixels of a texture that end up in the pixels for the screen space.
these texels can either be explicitly picked up from a raster map, when you use images as texture maps, or handled to the engine by an algorithm (or the result of mixing more then one) when they are from procedurals.

when texels are stored the rendering engine then decides what to do with them.
if they are part of the colour shading process they are handled to some channel of a shading model like phong.
the shading model then is also handled the normals per pixel and does its work taking into account lights, camera etc.

if they are part of a bumpmap though things change.
texels aren't handled anymore to a shading model, they are instead "bumped" and handled to the normals array.
bumpmapping as a technique looks up a pixl, looks up the neighborhood, and from the difference between those values figures out an angle to bend the normal at.
the bent normal interacts with light so that the surface seems to be different from the actual geometry.

now, if you handle textures that create a bump to a filtering algorithm, like an eliptical filter, the filter will constantly change texels to accomodate an aliasing correction that is colour based, this will however constantly bend normals in that texel in a different way at every frame, making bump pop like mad.
also, as this is generated when normals are handled to the shading process, oversampling the screenspace AA hardly ever helps much.

the solutions to popping bumpmaps are something different from a filter at texel level (which is what you want for colour maps).

one of the most common solutions is introducing a step value in maps handling, like MRay has.
a non-adaptive stepping value will force the engine to read and compute data for maps NOT RELATIVELY to the screen space, so that a full and consistant array of normals will be handed to the shading process AT ALL TIMES (and then eventually be averaged per pixel if the detail is not enough to fill the screenspace alloted to the object), eliminating the inconsistancy between frames at the root.

Julez4001
08-27-2005, 11:27 PM
Can we create a list that solves Flickering?

1. Render Twice the size (no AA)

Okay someone else.


(because this problem is driving me crazy).

annaleah
08-28-2005, 12:44 AM
Can we create a list that solves Flickering?

1. Render Twice the size (no AA)

Okay someone else.


(because this problem is driving me crazy).


Chewy must know something to fix this issue.
Come on Chewy tell us all the answers......please?

grafikdon
08-28-2005, 06:10 PM
I'm not sure it has anything to do with image file format 'cause i still get the flicker sometimes regardless of the image format. Hopee they nail it on LW9.


*Wouldn't hurt to have something like errr...thinking particles, more like Max's delegates*

Zarathustra
08-28-2005, 07:15 PM
This complaint tends to be part of what can be termed "freshman" syndrome. Flickering textures can be experienced even within Pixar's Renderman if you don't understand what you can and can't do.

Chewey's a long time member, which makes me think he's certainly no "freshman" when it comes to LW. This comment of his sounds like he either knows how to escape the problems of flickering textures or knows where all the limits are on the subject.

Chewey: I was hoping you wouldn't mind elaborating a bit and perhaps sharing a bit of that wealth of knowledge and experience with the community. Would you mind?

pixym
08-28-2005, 07:30 PM
I hope LW to have these kinds of sampling (Link (http://www.spot3d.com/vray/help/VRayHelp150beta/examples_image_sampler.htm)) but I really think it is utopic :(

Beamtracer
08-28-2005, 10:35 PM
I usually render Lightwave elements at twice the output resolution, then scale down. That gets rid of the stair-stepping (although render time is obviously affected!)
What you are essentially doing is bypassing Lightwave's anti-aliasing, and letting some other app do it instead.

Julez4001
08-29-2005, 04:03 AM
http://www.flarenova.com/eyelevelBG_Huge.mov


heres a example of standard flickering in any of my scenes.
I got bump ont he floor and the wall and can't get them out.
Please help!

otacon
08-29-2005, 04:26 AM
Whats your aa level set to? It looks low because i see some aliasing problems on the edges too. You could remove the small bumps, because they probably wont be seen anyway, or make a distance to camera gradient so they fade off in the distance.

Freak.
08-29-2005, 06:49 AM
What you are essentially doing is bypassing Lightwave's anti-aliasing, and letting some other app do it instead.

There are various way to do it directly from within LW itself.... You don't need a NLE or PS
to resize, LW can do it just as well..... I don't see how that's passing the AA off to another
program, when i'm not using another program..... (but LW itself)

But if anybody can get a simple example scene that suffers from this problem..
i'd be glad to find ways to get rid of it.

AA is one of those unprecise sciences, that has no good outcome....
Certain AA methods will work sometimes, others at other times, and sometimes not at all....

I'd be almost willing to bet, that if they added a new AA routine, that fixed all the problems,
it would be substanially slower than any we have now.......
Kudo's to NT for adding the new Lanczos, Mitchell, etc routines.... Which can help!!!

The upsizing thing, which has been a way around this time began, is still an easy fix...... Again, A quick google search find this argument goes back a long time, and affects just
about every 3D program, HardwareGPU, Procedural Texture or GamesEngine in history

Julez4001
08-29-2005, 05:12 PM
Whats your aa level set to? It looks low because i see some aliasing problems on the edges too. You could remove the small bumps, because they probably wont be seen anyway, or make a distance to camera gradient so they fade off in the distance.

Sorensen Squeeze it
while the edges may screw up a little under the compression, the flickering/crawling
is still there in the perfect version with clean edges.

Jarrede
08-30-2005, 03:24 AM
http://www.flarenova.com/eyelevelBG_Huge.mov


heres a example of standard flickering in any of my scenes.
I got bump ont he floor and the wall and can't get them out.
Please help!

I've recently spent a lot of time pulling scenes apart to figure out what the largest causes are for a chattering effect to show up in final renders.

I've come to the conclusion that it can be a multitude of different things, with some being more noticeable than others.

SO, I'd like to post my findings and discuss...here's a small list of what I've found so far that can contribute to chattering...Sorry if this is a reposted topic...I can't even read right now to do a search, so if yall don't mind I'm just gonna fill the board up with a single redundant topic.

Busy HDRI images in reflection channels.

Large Black Domes that were used for transparency raytracing being reflected onto tiny objects a large distance always. This was the most noticeable issue.

Very small procedural textures are an extreme no no! ...

A small Area light far away from objects with a shadow quality of 4 or lower can also contribute to chattering.

Higher AA levels set in bump channels

And, lastly, sometimes higher global AA settings will dampen the problem

annaleah
08-31-2005, 03:20 AM
I've recently spent a lot of time pulling scenes apart to figure out what the largest causes are for a chattering effect to show up in final renders.

I've come to the conclusion that it can be a multitude of different things, with some being more noticeable than others.

SO, I'd like to post my findings and discuss...here's a small list of what I've found so far that can contribute to chattering...Sorry if this is a reposted topic...I can't even read right now to do a search, so if yall don't mind I'm just gonna fill the board up with a single redundant topic.

Busy HDRI images in reflection channels.

Large Black Domes that were used for transparency raytracing being reflected onto tiny objects a large distance always. This was the most noticeable issue.

Very small procedural textures are an extreme no no! ...

A small Area light far away from objects with a shadow quality of 4 or lower can also contribute to chattering.

Higher AA levels set in bump channels

And, lastly, sometimes higher global AA settings will dampen the problem


Thanks.
Good things to look for.

PixelInfected
09-03-2005, 12:22 AM
when you have very fine dectails, better solution is to disable adaptive rendering which is a very bad beast for render.

gerardo
09-03-2005, 02:31 AM
Other tip that sometimes works is to make a copy of the flickering texture (Image Editor) and to apply it a little of blur. Then in the surface, set a distace_to_camera gradient (as alpha) on top, below, set the original texture and then the blurred copy. What happens is that texture portions that are near to camera, will be shown as the origial; and texture areas that are far away to camera, will be shown a little blurred. If we are using procedurals we can apply it to a blank image (TexturedFilter in ImageEditor) and reuse it in Surface Editor as any bitmap.



Gerardo

Netvudu
09-04-2005, 09:12 PM
when you have very fine dectails, better solution is to disable adaptive rendering which is a very bad beast for render.

Actually, given how Adaptive sampling works it should ALWAYS be deactivated for anything but stills. Seeing how the pixels being antialiased are different for every frame, you´re screaming for flickering.

PixelInfected
09-05-2005, 05:07 PM
adaptive sampling is useful be cause it allow you to render faster, it decide how is the amount of pixels that need antialias or not, if you have ones of follow items you must not use adaptive sampling.

- sasquatch (result with AS is a bad fur)
- RPF export (some channel not work)
- Texture with high fine little dectails (flickering)
- some procedural that not blurred
- very thin objs

Activator
10-26-2005, 02:09 PM
I was having a MAJOR vibrating problem (and an unhappy client) with the texture on a title that has a "brushed metal" look. Thanks to this thread, I solved it!! :bounce:

I blurred the "brushed" texture map sightly in Photoshop so it wasn't so "sharp" and, turned off Adaptive Sampling. This has solved it 90% and the small amount of vibration is accceptable now.

Thanks!

Julez4001
10-26-2005, 02:40 PM
Thats Good to hear....
We a need a LW bug/workaround list?
Not something to report to Newtek but how to bandage the problem till it does get fix.

heynewt
10-26-2005, 03:08 PM
Thanks for this thread (and good to see you on here, Julez, in addition to the Messiah forum) . These shimmering textures after render are the bane of our existence at my company. We fight them constantly. I've been following this thread and I'm about to start a lot of test renders to see what we can do based on the tips cited here. THanks a bunch for everyone's ideas.

Yes, we've found that upping the aa helps a lot with the shimmering, but it kills us on render times. It's just not practical if you've ever done a mass of limited budget CGI shots for a cable show. That's pretty much what we've been doing for 6 years. On the shows we do, there are nothing but last minute emergency changes and never the time or budget to go high aa on any shot or to build a huge render farm. We budget for medium aa. In emergencies we'll even go low (enhanced) aa in a pinch. Now we're considering Fprime as well, but I need some kind of numerical "standard" for when a render is done.

The one consoling factor, and I hate this, is that I've never had a shot come back from QC at any channel because of shimmering, though I've sent a bunch up there and bit my knuckles waiting. I hate it because it means a shot goes on the air that has a noticeable flaw in it. But apparently it's a problem with so many companies that a lot of networks let it slide. Have you ever noticed the hastily assembled 3D shots for network news shows? They're full of shimmering.

I just want to keep pounding this with Newtek. Nothing else they do is more important to my bottom line than fixing this shimmering/crawling/vibrating texture problem (or at least doing something to the renderer that minimizes it somewhat).

Robert Newton

Glendalough
10-27-2005, 08:32 PM
Please write more about this!

www.theoilcans.com

gerardo
10-28-2005, 03:27 AM
According to Emile Smith in his interview on Spinquad, is advisable to turn off animated_dither and avoid non-planar polygons,
I guess he is referring to a straight rendered image, because I've also noticed that adding film grain in post, can help to hide some flickering problems.



Gerardo

narph
01-09-2006, 05:59 PM
Other tip that sometimes works is to make a copy of the flickering texture (Image Editor) and to apply it a little of blur. Then in the surface, set a distace_to_camera gradient (as alpha) on top, below, set the original texture and then the blurred copy. What happens is that texture portions that are near to camera, will be shown as the origial; and texture areas that are far away to camera, will be shown a little blurred. If we are using procedurals we can apply it to a blank image (TexturedFilter in ImageEditor) and reuse it in Surface Editor as any bitmap.
Gerardo

would you mind expounding on these two techniques, or perhaps point me to a link where they're explained?

Great thread..cold comfort that I'm not the only one with squirm-itis..I'm off to try the higher AA and mipmap angles..

narph

gerardo
01-10-2006, 10:48 AM
would you mind expounding on these two techniques, or perhaps point me to a link where they're explained?

Great thread..cold comfort that I'm not the only one with squirm-itis..I'm off to try the higher AA and mipmap angles..

narph



I haven't seen any website with the trick of blurred and normal versions with distance_to_camera gradients, but I've used it with success in some situations. The second tip is from Dave Jerrard or Splinegod (is very old as you can see :D) you can find this cool tip here:
http://forums.cgsociety.org/showthread.php?t=220429
(see Splinegod and Dave Jerrard posts)
And here:
http://www.spinquad.com/forums/showthread.php?t=831
or here:
http://www.spinquad.com/forums/showthread.php?t=5250
or here
http://www.spinquad.com/forums/showthread.php?t=9329
(see Splinegod posts)
the tip not only works with UVMaps and has several uses as you realize (I've also applied it to speed up my soft_reflections trick)
About the camera gradient and blurred version, the process is really simple:
You can use a bit map or a procedural applied on a blank image as the tip above mentioned, clone it and add FPBlur to this clone:

http://www.geocities.com/gerardstrada/fblanc.txt

Then in bump channel (may be other channel but is specially useful for flickering problem on bump channel) add your original image map (the sharp one), above this layer add a distance_to_camera gradient (you need to calculate the distances previously); below all layers (as base layer) set the blurred version of your bump map (the clone).

http://www.geocities.com/gerardstrada/fgrad.txt

That's all.
Here you can see an ugly comparison (sorry, yesterday I didn't sleep)

http://www.geocities.com/gerardstrada/fflick.txt http://www.geocities.com/gerardstrada/fnoflick.txt

First image hasn't the trick and second image has this simple trick applied.
Btw, I didn't use antialiasing but I reduced the image a little :)



Gerardo

narph
01-10-2006, 01:54 PM
Thank you Gerardo..big help..I'll be trying those tips today.

Also, after checking other suggestions in this thread, I was disappointed to learn that my scene already HAD such settings, like mip map set to high, no procedurals, etc.

but what has helped was cranking mip map levels (at high) from 1.0 to 3.0! Flickering is still there, but it's greatly diminished..I'm tempted to crank it to 6.0 and see what happens to both flickering and render time..

narph

dmaas
01-10-2006, 04:21 PM
Lightwave has a serious bug related to the mipmap intensity setting.

Basically, Lightwave reduces the mipmap intensity (behind the scenes, without telling you) depending on how many AA passes you are using. This is incorrect; the texture filter size (which is what "mipmap intensity" really controls) should depend only on the output resolution, not the number of AA samples.

The solution, as you have found, is to pump up the mipmap intensity. How much depends on the number of AA passes (I think using the square root of the number of AA passes is ideal - e.g. with 9-pass AA you want to set mipmap intensity to 3.0). This way you will end up with a final intensity of 1.0 after Lightwave applies its misguided "adjustment."

Of course, if you do a test render without any AA the texture will look very blurry, but it will look good at the proper AA level.

Perhaps someone could write a plugin to go through all surfaces and automatically fix the mipmap intensities just prior to rendering?

narph
01-10-2006, 10:41 PM
OK..boosting the mip map value to higher levels made a difference for me, in conjunction with enabling shading noise reduction.


I am still getting more noise than I'd care for from the Area light, but that's for another thread, I s'poze.

thanks to everyone who posted; I hope my post can help somebody out there..

narph

gerardo
01-11-2006, 04:16 AM
Yea, nice tip. it would be interesting if someone could write a plugin to compensate this in every bitmap layer automatically as dmaas says



Gerardo

brap
01-11-2006, 03:39 PM
yes, some fantastic info in this thread. Thanks dmaas and gerardo for sharing some great tips! :thumbsup:

narph
02-13-2006, 04:49 PM
Well, after having gotten flicker down to the acceptable level in a 720p frame size, it's now back in a smaller frame size! same scene, same lights, same settings, except that now, I'm rendering at 864 x 486.

Can anyone explain why the flickering is now back in this scene when rendered at a smaller frame size?

Thanks much..

I'm experimenting with higher AA in the meantime...

narph

lightwolf
02-13-2006, 05:06 PM
2 - Apply the image texture layer twice (or more), with different filter strengths. Create a gradient (Distance to Camera) to blend between them, so that the higher strength will be more visible further away from the camera. - This will only help with image textures though

3 - Motion Blur is your friend ;)

Edit: oops, I seem to have read the thread in the wrong direction, sorry for that...

Cheers,
Mike

narph
02-13-2006, 06:17 PM
when you say "with different filter strengths" do you mean opacity?


n

otacon
02-13-2006, 06:48 PM
I think he means different mipmap settings.

mocaw
02-13-2006, 09:19 PM
2 - Apply the image texture layer twice (or more), with different filter strengths. Create a gradient (Distance to Camera) to blend between them, so that the higher strength will be more visible further away from the camera. - This will only help with image textures though

3 - Motion Blur is your friend ;)

Edit: oops, I seem to have read the thread in the wrong direction, sorry for that...

Cheers,
Mike

This is one of the production examples in a certain "other" software package and seems to solve many of these problems. Even though it only works with image textures the new camera baking should allow us to take procedurals, bake-em out, and then reapply them this way as images with distance to camera controled by gradients.

Maybe someone will come up with a filter node as well that utilizes a folder with several different resolutions of your image and uses something like eliptical filtering to sort out errors and choose the correct map for that area? Maybe it could be one step better in that it could generate the procedurals INTO an image texture at render time, resample it X times and THEN do the filtering! OK now I'm just dreaming...

Hey LightWolf...you know how to code right...and there is that nodal SDK...hmm...

lightwolf
02-14-2006, 10:53 AM
when you say "with different filter strengths" do you mean opacity?

As otacon said, MipMap Strenght is the term in the UI...

Cheers,
Mike

lightwolf
02-14-2006, 10:55 AM
Maybe someone will come up with a filter node as well that utilizes a folder with several different resolutions of your image and uses something like eliptical filtering to sort out errors and choose the correct map for that area? Maybe it could be one step better in that it could generate the procedurals INTO an image texture at render time, resample it X times and THEN do the filtering! OK now I'm just dreaming...

Hey LightWolf...you know how to code right...and there is that nodal SDK...hmm...
You might as well create a node that does decent filtering in the first place...

Since infiniMap supports all the image projections that LW uses (and is internally more accurate than LW as well) it should be possible to turn it into a node that handles native LW images as well...
That might be something to aim for after the nodal versin is done :)

Cheers,
Mike

narph
02-14-2006, 07:43 PM
can someone post a link to or give a description of how to do this camera trick? I tried a couple things, but must be getting it wrong.

Lightwolf; I've played witih mip map settings, but to no help. My larger frame size seemed to get a benefit from increasing mip map, but not so the smaller one — which is THE same scene!

I'm almost to the point of chucking the bump maps after having blasted away for 8 weeks, only to be about where I started with squirming flickering textures.

I'd trade 1000 whizzy new features just to have some of these basics fixed.

n

narph
02-14-2006, 11:41 PM
OK..I think I see what I did wrong earlier..reread the tips above and re-rendering a test.

n

narph
02-15-2006, 01:10 PM
Using this blurred copy of a bit map and the camera gradient trick, I've knocked the flicker down a lot, but some is still there.

Any hints as to what the cam settings or blur settings ought to be. I set the blur so that it looked a little blurred, and the cam gradient, I think to be at 0, 1/3 meter and 2.5 meters..just a guess based on the size of my scene.

thanks!

n

CGTalk Moderation
02-15-2006, 01:10 PM
This thread has been automatically closed as it remained inactive for 12 months. If you wish to continue the discussion, please create a new thread in the appropriate forum.