Why I Don't Like PBR

[Flea Yatsenko]

2k/4k would be really good if used properly. If people packed things properly and added multiple materials into a single texture, besides the local improvements, that's also less network requests. Network requests are stuck behind your ping, that's one of the biggest drivers of slow rezzing.

A 2k is four times as large as a 1k. Blender's new UV packer works amazingly well and if you are using it, you have to really screw up to make poor use of your space.

That said it would completely get abused by people. I imagine clothes with 2k textures on everything just because it looks slightly better than 1k.

LL should start a program where they test you on your content creating abilities and it unlocks more advanced features like 2k/4k textures.

[Extrude Ragu]

I think that newbie creators/content farm types spamming up the grid with laggy content is not a new problem. Worth solving, sure. New problem? not really.

In theory if a creator uploaded a 2k texture and slapped it on their cube, your computer would only download say a 1k version of it until you zoomed way in, that's how I'm told it will work. I'm also told that a viewer dev would be free to set an arbitrary max resolution to download so in theory this won't actually change anything for people on low end hardware. I don't know or claim to know that it actually does/will work, I'm just relaying what I've been told.

 

 

 

[Porky Gorky]

12 minutes ago, Flea Yatsenko said:

LL should start a program where they test you on your content creating abilities and it unlocks more advanced features like 2k/4k textures.

Yeah we need a levelling system like D&D. Get to lvl 100 and you unlock height map displacement and ray tracing.

[Henri Beauchamp]

54 minutes ago, Porky Gorky said:

The creator was using 8 materials on the chair, so that would be 32 x 1k textures which is absurd.

If 2k textures are rolled out maybe LL could offest the impact by heavily reducing the number of surfaces/faces available on each piece of new mesh.

Not at all, you'd get 2k textures instead of 1k ones everywhere, because every creator would always upload their highest resolution (2k) textures (and only them: why spending more in uploads and ”wasting” time in selecting the right texture version when building stuff ?) and reuse them for all their builds, whatever the final object size, and whatever the face area on which the texture is applied !

Sure, the viewer is capable of downsizing textures to fit them in VRAM, based on the calculated virtual surface area, but the latter changes with the FOV and when your avatar moves around, or when you cam around, the said surface changes, better level of details are used and the larger versions of the textures are used in VRAM.

The result is that, on the network side, you will almost invariably end up downloading the full size texture, and the latter will stay in RAM for as long as even the lowest LOD is used (because the viewer cannot know if, after having cammed closer and then farther to the face bearing that texture, you will not cam close again soon). As a result, you can see viewers eating up easily 24GB or RAM in textures-heavy sims... Just imagine what it would be like with 2k textures occupying 4 times the amount of memory 1K textures are using !

In VRAM, with GL images, things can even go more hectic, because of ”boosted” and ”no delete” GL images, and even after having ceased to render a given texture, it can linger in VRAM forever (this is why you almost invariably see the viewer using more VRAM after even a short session while you returned at your login place and waited patiently for the viewer to expunge all objects and textures, and disconnect from the sims you left). I managed to achieve a better behaviour in the Cool VL Viewer, after many weeks of careful auditing of the code, of redesign of parts of it, and of work around design and implementation for the remaining shortcomings, but while it works well for 1024x1024 textures, even with only 1GB VRAM, it would definitely be at pain with 2k textures (4x the memory consumption).

Edited February 27 by Henri Beauchamp

[Zalificent Corvinus]

2 hours ago, Porky Gorky said:

If 2k textures are rolled out maybe LL could offest the impact by heavily reducing the number of surfaces/faces available on each piece of new mesh.

Oh dear god no!

One of the biggest performance hits is the number of separate rigged links in a rigged mesh body or clothing item.

 

Alpha cuts on a mesh body for example, with only 8 faces permitted per link, a mesh body using alpha cuts causes lag. It's not draw calls, people who basically don't know what they are talking about, or just don't pay attention keep saying "blah blah blah draw calls, lets use 4k texture atlases".

 

Draw calls are NOT SL's biggest performance problem.

 

[Extrude Ragu]

1 hour ago, Zalificent Corvinus said:

Alpha cuts on a mesh body for example, with only 8 faces permitted per link, a mesh body using alpha cuts causes lag. It's not draw calls, people who basically don't know what they are talking about, or just don't pay attention keep saying "blah blah blah draw calls, lets use 4k texture atlases".

🤦‍♂️

Alpha cuts cause lag because they result in additional draw calls. Remember how before PBR, there was this great big performance improvement update work that went on? It was in response to all the bodies with ridiculous number of alpha cuts. What did the work involve, it involved detecting which unique faces shared the same material information, then batching them into a single draw call! That was the entire optimisation that sped everything up, removing a bunch of additional draw calls.

That was literally the whole point.

[Extrude Ragu]

I hate to sound like a smartass but pls like all the viewer developers were talking about this for ages in the internal discord, in the viewer meetings. Ask Beq Janus yourself. What comes up again and again and again? draw calls. It's not some boogeyman that people just made up.

The mesh data gets sent to your GPU in chunks, every draw call gets sent as a seperate message. The time it takes to send that message is usually longer than the time it takes to process it. Why is that? The gpu is incredibly fast at processing triangles, but the bottle neck is not the gpu, it's sending data to the gpu in tiny chunks. Usually those chunks are each of the faces in a mesh.

Think of it similar to copying 100 tiny files to copying and pasting one big file. The big file always copies faster.

[Love Zhaoying]

Sounds like one of those cases where you have to..

..draw your own conclusions!

[Extrude Ragu]

Quote

Perhaps more significant for performance (though this is very tentative and it remains to be seen in practice) is news from Runitai Linden at yesterday's content creator user group meeting, that he is hoping to have some changes that directly address a large part of the problem that heavily sliced mesh bodies cause. My other blogs explain the concept of "batching" and drawcalls, Runitai's changes will (hopefully) bring improved batching to rigged mesh, cutting down the number of draw calls required. This is very early days and Runitai cautioned that the changes make many shortcuts and assumptions that may not survive contact with the real world. 

https://beqsother.blogspot.com/2021/11/i-dont-wanna-mesh-with-nobody.html

 

Quote

Here's a quick appraisal of the typical perspective on lag. The high-level summary is that most of these are valid observations and identify some form of inefficiency. Whether they contribute to FPS loss is another question, and until we get rid of the massive issue around draw calls, their effect is moot.

https://beqsother.blogspot.com/2021/09/why-crowds-cause-lag-why-you-are-to.html

 

Edited February 27 by Extrude Ragu
add link to source

[Zalificent Corvinus]

8 minutes ago, Extrude Ragu said:

Ask Beq Janus yourself.

There have been threads where some TPV devs claimed textures caused all lag, some years back, then there were threads where some TPV devs claimed "triangles" were evil, then there was a thread where your Hero-Dev, specifically stated, with supporting stats, that it's the RIGGING on mesh that causes the laggy performance, and that the 8 face per link limit means more separate links, each of which is rigged, that causes the performance loss with avatars.

 

All these threads took place right here on the forums, for all to see, not on some snotty discord, or some middle of the night dev group meeting on the beta grid.

 

What we haven't seen is Hero-Des starting threads called "draw calls are EVIL".

 

18 minutes ago, Extrude Ragu said:

it's sending data to the gpu in tiny chunks. Usually those chunks are each of the faces in a mesh.

Think of it similar to copying 100 tiny files to copying and pasting one big file. The big file always copies faster.

That's a bad analogy, and I suspect you don't know enough about either subject to understand why.

Do you know the real reason why copying a 100kb file is faster than copying 100 1kb files?

 

15 minutes ago, Extrude Ragu said:

What comes up again and again and again? draw calls. It's not some boogeyman that people just made up.

Lot's of things come up again and again, usually as a result of people talking out of their butts.

 

"Textures are bad, mkay" came up again and again, as did "triangles are bad, mkay" , and "complexity are bad, mkay" still comes up again and again, despite being proved to be a useless metric, as does "script memory are bad, mkay" from people who don't know the difference between old-lsl and mono-lsl.

The "textures must be twice the size of my monitor" stupidity comes up again and again too.

 

 

[Extrude Ragu]

Yes well whilst you work on saving the world by making everyone your 'be smarter' serum, I'm going to trust that the lead firestorm developer and one of the top engineers at LL knew what they were talking about. Actually I've personally experienced the results of their work as I take yearbook photos for my sim yearly and the FPS difference after the work had been completed was night and day.

[Love Zhaoying]

13 minutes ago, Extrude Ragu said:

https://beqsother.blogspot.com/2021/11/i-dont-wanna-mesh-with-nobody.html

 

https://beqsother.blogspot.com/2021/09/why-crowds-cause-lag-why-you-are-to.html

 

Oh, yeah?!? What does she know?!? LOL!!!

[Theresa Tennyson]

15 minutes ago, Zalificent Corvinus said:

Lot's of things come up again and again, usually as a result of people talking out of their butts.

Mmm hmm...

[Qie Niangao]

The thing is, we all know with zero doubt that if we have 2K textures, they will be abused. And if we're honest with ourselves, we know they will be mostly abused.

So for the handful of trim sheets in a scene that could actually benefit from all 4.2 megapixels in a 2K texture (times usually three of the four possible maps), for those few very special cases we'll all sit around watching the texture console thrash as an incessant stream of the highest possible resolution zipper and button textures clog our downloads.

I wish I could worry about draw calls. Most of the time my machine is starved for anything to draw with.

[Zalificent Corvinus]

33 minutes ago, Extrude Ragu said:

https://beqsother.blogspot.com/2021/11/i-dont-wanna-mesh-with-nobody.html

You know I just read that page.

It talks about multi segmented rigged mesh bodies, that I mentioned earlier, and which were also the subject of a thread right here on the forum.

Yeah the second blog post talks about "draw calls are evil, mkay", but lets get realistic here, these "hero devs" have touted different causes every couple of years. It also dismisses the "triangles are bad, mkay" claims of a couple of years earlier.

 

Remember when loudmouths claimed that having a complexity score over 25k meant you were a public enemy of SL and should be banned, and that LL should CAP max complexity, rendering 90% of your inventory illegal to use.

The loudest voice in that club was a TPV dev albeit not a particularly good one.

 

Would batching draw calls help, probably. BUT that second blog post from 3 years ago, seems to support the idea that we'll all switch to non-segmented bodies, with only 2 draw calls, 110% BoM Fascist alpha layers for everything. And that isn't happening, time to pull the head out of the sand and stop worrying about draw calls you can't fix, and concentrate on things you CAN fix.

Slinks ReSux bodies were a colossal failure, Kupra is losing popularity, the "winners" in the body wars are all segmented.

 

Adding 2K or 4K resolution textures is NOT a fix, it's a wishful thinking "surely creators will use these wisely" pie-in-the-sky nonsense.

 

Reality is "I could use a 32x32 pixel black flood fill for the back of the buckle, but four-times-the- size-of-most-peoples-monitors 4k leetnes 22 mb.dds files with 13 mip levels for the win".

 

Edited February 27 by Zalificent Corvinus

[Love Zhaoying]

25 minutes ago, Qie Niangao said:

I wish I could worry about draw calls.

All I know is, if I wear a belt, then may drawers don't fall down.

[Qie Niangao]

1 minute ago, Love Zhaoying said:

All I know is, if I wear a belt, then may drawers don't fall down.

Yeah but is the back of the belt buckle sufficiently detailed? We're competing with triple-A drawers here!

[Love Zhaoying]

Just now, Qie Niangao said:

Yeah but is the back of the belt buckle sufficiently detailed? We're competing with triple-A drawers here!

If I let the back of my pants hang below my waist, I can talk out of my butt!

[Qie Niangao]

1 minute ago, Love Zhaoying said:

If I let the back of my pants hang below my waist, I can talk out of my butt!

and here I wasted all these years learning ventriloquism.

[Love Zhaoying]

I posted this "PBR Related" thread and received no replies yet..

Summary: AFTER PBR, existing old builds are "too dark". I thought you had to do something special to make it look "good" in the dark, but just using some local lights is enough..?

 

 

[Chic Aeon]

So THIS is what happens when you put a piece of furniture with a probe inside a house with a probe.  Lighter area is a "reflection" of the probe prim.  I am testing some stuff so if I am incorrect please let me know. 

Works MUCH better in a house without a probe.  

 

So we have an issue with @Charolotte Caxton FOLLOWING best practices and Dutchie "doing what works" LOL.  Which is VERY MESSY and I suspect it will be for some time to come.    

Edited February 28 by Chic Aeon
adding info

[Charlotte Bartlett]

13 hours ago, Chic Aeon said:

So THIS is what happens when you put a piece of furniture with a probe inside a house with a probe.  Lighter area is a "reflection" of the probe prim.  I am testing some stuff so if I am incorrect please let me know. 

Works MUCH better in a house without a probe.  

 

So we have an issue with @Charolotte Caxton FOLLOWING best practices and Dutchie "doing what works" LOL.  Which is VERY MESSY and I suspect it will be for some time to come.    

That’s a bit arbitrary.  You should post what the probe settings are etc and set up.  
 

Anybody can attach a probe to a “bit of furniture” but in reality indoor furniture will most likely be inside houses so furniture makers are going to need to take this into account and house makers are going to experience the same challenges as customers can have furniture from multiple creators all who no doubt will fudge things a different way    

I bet I could make a mirror inside one of my houses and  post the opposite result you share   I will do an example if helpful.

The point remains the same as we have with EEP settings, the variables are there.  Those variables when users are creating a scene (or setting up their items) means adjustments are going to be interesting and frustrating.  
 

I am speaking to two major furniture creators now about doing some co projects so our products “compliment” each others set up.   I will publish those outputs once done if furniture makers want to test their items in my houses they are welcome to (and vice versus).

 To my mind one of the ideas of the probe inside a house is so the output is stored and which can be used by furniture inside the house with reflective materials.  

I assume you meant to tag me with the “best practice” statement LOL, but either way my only learning comes from Unity and then all the workarounds SL needs.    I do the best I can with what I have.  
 

I am a hobbyist with very limited time snd busy RL career, so can’t provide the same expertise a professional will have.   Instead I put my effort into learning,  testing, and adjusting so at the minimum my customers know all my effort I can afford is to do the best possible with the cost/benefit taken into account.  

Results may vary. 

 

[PheebyKatz]

Every time I look at this thread again, my Spock eyebrow goes up and I catch myself saying, "Fascinating."

I haven't even really seen any of this stuff inworld yet, but then I'm old-fashioned and don't get out much. It does seem complex enough to keep everyone busy for a few years, finding the proper-SL-balance between best practices and what works.

This is a very informative thread, thank you guys for eviscerating the issues and displaying the entrails so artistically. I have a strong appreciation for this thread's content.

[AmeliaJ08]

2 hours ago, PheebyKatz said:

Every time I look at this thread again, my Spock eyebrow goes up and I catch myself saying, "Fascinating."

I haven't even really seen any of this stuff inworld yet, but then I'm old-fashioned and don't get out much. It does seem complex enough to keep everyone busy for a few years, finding the proper-SL-balance between best practices and what works.

This is a very informative thread, thank you guys for eviscerating the issues and displaying the entrails so artistically. I have a strong appreciation for this thread's content.

The Winter Wonderland was all PBR this time Pheeby, it was really pretty. There was snowball war Capture The Flag too!

 

[Rowan Amore]

2 hours ago, PheebyKatz said:

Every time I look at this thread again, my Spock eyebrow goes up and I catch myself saying, "Fascinating."

I haven't even really seen any of this stuff inworld yet, but then I'm old-fashioned and don't get out much. It does seem complex enough to keep everyone busy for a few years, finding the proper-SL-balance between best practices and what works.

This is a very informative thread, thank you guys for eviscerating the issues and displaying the entrails so artistically. I have a strong appreciation for this thread's content.

Violent Seduction has a "PBR enabled" outfit at The Warehouse sale.  I'll be checking that out today using both viewers to see how it looks.  Not sure I understand how that's supposed to make clothing better so we'll see.