What's Wrong with This Picture?

[Chic Aeon]

I was wondering about the best place to put this but I decide Merchant's was better than the Mesh board LOL.

I got a blogger copy of an item today. In it was a notecard about LODs and more ^^. Reading it, I sighed. I didn't actually CRY you understand but much head shaking was in evidence. The odd thing is that the item that came with that note looked fine at LOD 2. I upped my setting to 4 to check and could see no difference. So that notecard didn't need to be included at all. 

Names deleted . Bold is mine

 

Quote

 

In order to see the mesh correctly you can increase the LOD (Level of detail).

Follow those few steps: 

1. CTRL+ALT+D to activate the Advenced menu 

2. In the menu click on "Show debug settings"

3. A window will appear. Look for:
    RenderVolumeLODFactor 

4. Set as value a number around 7.000 - 10.000

----------------------------------------------------------------

AUTO- ATTACH

In order to activate the auto-attach of the props, follow this instructions:

1. Go to "About Land"

2. Last folder - EXPERIENCES

3. <MODERATOR REDACTED>

Done

Have Fun!

 

 

 

 

Edited June 6, 2017 by Dakota Linden
Please do not post specific information about item or seller

[ChinRey]

Trying to come up with a good reply but I think you've said it all.

[Whirly Fizzle]

We really need this....
BUG-6243 - Provide an informative warning when creating sculpts or mesh that may render improperly for others

[Chic Aeon]

1 hour ago, Whirly Fizzle said:

We really need this....
BUG-6243 - Provide an informative warning when creating sculpts or mesh that may render improperly for others

So this feature would say for someone with LOD set at 4 give a warning when they uploaded?  I think that is a fine idea however I don't necessarily go along with the reason why creators upload based on high settings :D.  Some apparently (they have been quoted) simply don't care.   Still especially for new folks this would be good. IF that warning happened it would be nice if the creator could set what level they wanted the warning at.  For me, at 2 (and I hardly even change the LOD past that -- if it doesn't look good at 2 it doesn't get blogged *wink*) I wouldn't want to be nagged.  

Even with our LOD settings and the warning, it is really still up to the creator to test AND each of us will undoubtedly have different ideas on what is usable and how far we should be able to see an object. Lots of variables.  A good reason not to buy things without seeing them, methinks. 

[ChinRey]

4 hours ago, Whirly Fizzle said:

We really need this....
BUG-6243 - Provide an informative warning when creating sculpts or mesh that may render improperly for others

Two interesting obeservations: in 2014, three years after mesh had been introduced, Linden Lab was still unaware of the problem. In 2017, three years after @Soft Linden reported it as a bug and it was triaged as Major, nothing has been done about it. The JIRA was closed after only nine days - fix: "None", resolution "Accepted".

This was shortly after @Oz Linden took over. Maybe he can explain what happened and - more to the point - how no solution can possibly be regarded as acceptable for a bug as major as this?

[Whirly Fizzle]

36 minutes ago, ChinRey said:

Two interesting obeservations: in 2014, three years after mesh had been introduced, Linden Lab was still unaware of the problem. In 2017, three years after @Soft Linden reported it as a bug and it was triaged as Major, nothing has been done about it. The JIRA was closed after only nine days - fix: "None", resolution "Accepted".

This was shortly after @Oz Linden took over. Maybe he can explain what happened and - more to the point - how no solution can possibly be regarded as acceptable for a bug as major as this?

Well, it's not a bug, it's an improvement request.
The JIRA was imported so hopefully it's on the (probably very long) "to do" list.

[arton Rotaru]

OMG! The Jira is really from 2014. Where did all the time go?

Anyhow, I kinda like Softs Straw man proposal from today.

[ChinRey]

38 minutes ago, arton Rotaru said:

OMG! The Jira is really from 2014. Where did all the time go?

It is. But actually an even more puzzling question is why isn't it from 2011? It's not as if it wasn't the talk of serious mesh makers almost from day one.

 

40 minutes ago, arton Rotaru said:

Anyhow, I kinda like Softs Straw man proposal from today.

Yes.... maybe... or. Disabling the LoD system entirely for photo sessions would discourage good LoD models even more since poor ones won't show up on pictures.

It's a tricky problem, no b\doubt abut that. SL's land impact system for measuring load effectively punishes bulders who want to make good LoD models and that's a bad thing of course. On the other hand, the OS grid and the smaller grids all keep the old prim count system and that gives exactly the opposite problem: mesh makers tend to make too detailed models since the land impact is the same regardless. That's obviously why people say mesh don't work well on those grids. The fact is, the same mesh works exactly as well or poorly on any grid but no virtual environment can possibly work when all the content is ultra high poly and with no LoD simplification at all.

[arton Rotaru]

5 minutes ago, ChinRey said:

It's a tricky problem, no b\doubt abut that.

This quote is probably the answer to your rhetorical first question.

Yeah right, most likely there won't be a perfect solution for this, unless any mesh uploaded would require to be approved by an official Linden employee before it can be rezzed. But that would be kinda diametrically opposed to what Second Life actually is.

[Whirly Fizzle]

28 minutes ago, ChinRey said:

It is. But actually an even more puzzling question is why isn't it from 2011? It's not as if it wasn't the talk of serious mesh makers almost from day one.

It's been a problem long before that, as soon as sculpties arrived on the scene. Hmm was that 2007?
Creators who didn't know or care how to create sculpts that didn't collapse down to a pile of vertex vomit at a couple of meters distance would generally include the "Set LOD to 4.0 minimum" notecards in with their products.

[ChinRey]

1 hour ago, arton Rotaru said:

This quote is probably the answer to your rhetorical first question.

Yes. What I really reacted against when I saw that JIRA was that it appeared to have been closed after jsut nine days. That would essentially mean it was never seriously considered at all. It's a different matter if they've been working on it anyway of course.

[ChinRey]

53 minutes ago, Whirly Fizzle said:

It's been a problem long before that, as soon as sculpties arrived on the scene. Hmm was that 2007?

2007, yes.

A bit off topic but not completely and it fits the title at least. Tthis thread got me to check some of LL's official mesh documentation and here's a true gem I found there. This is part of their advice how to determine actual land impact for worn meshes:

Quote

Turn on wireframe mode and take a look at your attachments. If they still look solid, it is likely that they contain more triangles than are necessary and are incurring too much streaming cost on the people around you. You can turn on wireframe mode in the Develop menu by choosing Develop > Rendering > Wireframe.

(http://wiki.secondlife.com/wiki/Mesh/FAQ)

Can anybody spot what is wrong with that picture?

[Chic Aeon]

4 hours ago, ChinRey said:

On the other hand, the OS grid and the smaller grids all keep the old prim count system and that gives exactly the opposite problem: mesh makers tend to make too detailed models since the land impact is the same regardless.

Agreed, but the NEW UbOde system (with physics similar to SL) also has land impact in the mix. So things are no longer "one" no matter what. Not everyone is opting for the new system of course so there are three choices now in Opensim. Bullit, ODE and UbOde. 

Your point however is definitely correct. 

[Prokofy Neva]

@Chic Aeon Sounds to me as if there is now LOD inflation. Those cards used to tell you to set them at 4. Now it says 7?

@Whirly Fizzle I don't want a nag message telling me to adjust settings. There's already a lot I can't see, even with a regular "good" computer "meeting specs" from Best Buy (which is what LL has to produce for, not hand-built jobs from New Egg that their own devs make). And I'm used to that. My day is filled with unexpected glaring blobs, grey people, etc. It's up to me to adjust -- or not.

I always have the feeling that mesh is an alien creature in our world, it's not meant to be here and has been artificially granted like beech roses on to the shore. Does it work better in Sansara?  Maybe that's the idea.

[arton Rotaru]

8 hours ago, Prokofy Neva said:

Does it work better in Sansara?  Maybe that's the idea.

Mesh models are everywhere the same. There are certain rules given by the target engine, like LODs which a creator has to follow to achieve satisfying content. Content that doesn't follow the rules will be crappy content, no matter where you display it.

Sculpted prims were much more alien already, than mesh could ever be. Increasing the LOD factor to 4 was only introduced because creators didn't follow the engines rules, and created objects with sculpted prims, they never were intended for.

Indeed, the rules were abused with sculpties, and still are abused with mesh mostly due to the prim per sqm business model of Second Life. Which makes it somewhat understandable. But it's still no reason to work around the engines rules IMO.

[ChinRey]

2 hours ago, arton Rotaru said:

Mesh models are everywhere the same. There are certain rules given by the target engine, like LODs which a creator has to follow to achieve satisfying content. Content that doesn't follow the rules will be crappy content, no matter where you display it.

Yes and no. How the software handles the mesh can be very significant. Second Life's mesh render code is nothing but a crude hack of the prim code, meshes even have all the prim twisting parameters. It's obviously not very efficient. And the LoD system is the worst part of it. The setup with four fixed distance LoD levels works quite well with algorithmic shapes and procedural simplification but it's not suitable for complex "free" shapes like sculpts and mesh. To make matters worse, Linden Lab was never able to provide adequate advice how to use mesh effectively, their content creators were kept well away from the development process and their programmers only understood mesh in theory, not its practical application. I've already quote one "wrong picture" from the wiki, here are two others:

Quote

You REALLY don't want the the LDPW folks mucking about in the server code. Trust me.

(http://wiki.secondlife.com/wiki/Linden_Department_of_Public_Works)

That's absolutely, completely, totally and utterly wrong! LDPW should have been very much involved in every content creation tool project!

The second one is bordering to insanity:

Quote

A general guideline for creating LOD models is to reduce the triangle count by 50%-75% at each level. For example: If the most detailed model is 400 triangles, the next level should be no higher than 200 triangles. The next level should be no higher than 100, and the lowest should be near or below 50 triangles.

(http://wiki.secondlife.com/wiki/Mesh_and_LOD#Level_Of_Detail)

The people who developed mesh for Second Life honestly believed in this nonsense and that is where most of the problems lie: it doesn't matter how good or bad a programmer is if he/she doesn't understand what functions the code needs to perform.

 

Sansar is very different. It's been made with mesh in mind right from the start, using solutions especially suitable for mesh throughout.

 

3 hours ago, arton Rotaru said:

Sculpted prims were much more alien already, than mesh could ever be.

Not that different actually. If we look behind that silly color encoded mapping, a sculpt is nothing but a simplified and standardized method for representing a mesh. In theory it's a brilliant idea for an online virtual environment. A 1024 vertice mesh model done as sculpt only needs a Kb or less of data to be transferred and the simplification should also make it very easy for the client to render. In reality it didn't work out quite that way of course but that's only because LL made every possible mistake and a few impossible ones when they developed it.

[arton Rotaru]

I wouldn't draw the picture that dark actually. During Mesh Beta there were indeed content creators involved. I don't know how many of the LDPW were involved, I haven't seen many Moles either during Mesh Beta. I don't know how familiar they were with creating mesh models at all at the time. But there were defenitely some. The Lindens who implemented Mesh in Second Life were pretty smart people actually, that's for sure. And they defenitely knew what they were doing, and how it should work, and how it can be implemented along with legacy content. In my opinion Mesh works pretty well in SL as well. I don't have much to complain, besides a few very odd behaviors which are mostly related to the Physic Engine though.

The 4 LODs is one of rules of the engine. If that is ideal, or not doesn't matter that much. It's the rule, and following the rule will lead to content that works well in the engine. A reduction of at least 50% between the LODs is a quite common rule with game assets. If it's not 50 % less than the previous one, there isn't much point in reducing it at all, because of the little savings it would give, and swapping them would be more costly than keeping the previous one on screen. Reducing them more drastically will make it harder to have smooth transitions between the models. So 50 to 75 % reduction is good advice, which gives a good compromise between looks and land impact.

The problem with sculpts is, that they have to follow the same LOD rules as well, but opposed to mesh, you cannot create lower LODs yourself. And since  people made entire 1 prim bedrooms and whatnot out of them, instead of rather simple organic shapes they were intended for, the LOD rule didn't work out indeed.
Which is why they are much more alien to me than mesh ever will be.

Edited June 11, 2017 by arton Rotaru

[ChinRey]

1 hour ago, arton Rotaru said:

I wouldn't draw the picture that dark actually. During Mesh Beta there were indeed content creators involved. I don't know how many of the LDPW were involved, I haven't seen many Moles either during Mesh Beta. I don't know how familiar they were with creating mesh models at all at the time. But there were defenitely some.

According to Michael Linden, The WIlderness was LDPW's first attempt at making mesh. That was actually quite early - 2012 - and not bad for that time. But it still took two more years before they started to produce decent quality mesh consistently and even today I can't see any Moles among the top notch mesh makers in SL (although interestingly there is one former Mole in that group). The Moles are good builders and I'm sure they would have picked up the new techniques much faster if they had been invloved in the development right from the start.

 

1 hour ago, arton Rotaru said:

The 4 LODs is one of rules of the engine. If that is ideal, or not doesn't matter that much. It's the rule, and following the rule will lead to content that works well in the engine. A reduction of at least 50% between the LODs is a quite common rule with game assets. If it's not 50 % less than the previous one, there isn't much point in reducing it at all,

That's my main point. The 50% rule makes perfect sense in an environment with variable switch points but it does not take into account the rules of this particular engine. One example: I measured a kitchen chair 0.5x0.5x1 m - which is a moderately sized mesh. Switch point between high and mid LoD for an object that size is 2.55 m, less than the default camera offset. In other words, with default graphics settings what you see when you sit on the chair is the mid LoD, not the high. A 50% reduction in the polycount there would usually be way too much. For larger objects on the other hand, even 75% may not be nearly enough. The impression I get is that they read about that 50% rule somewhere and passed it on without taking into consideration the special way SL handles LoD.

 

2 hours ago, arton Rotaru said:

If it's not 50 % less than the previous one, there isn't much point in reducing it at all, because of the little savings it would give, and swapping them would be more costly than keeping the previous one on screen.

Oh yes. Unfortunately that isn't reflected in the land impact calculation though. Cutting down slightly on the polycount for the mid model won't reduce the actual load significantly and may even increase it a bit (depending on how SL handles identical LoD models - not sure about that) but it does help reducing the LI.

 

2 hours ago, arton Rotaru said:

The problem with sculpts is, that they have to follow the same LOD rules as well, but opposed to mesh, you cannot create lower LODs yourself.

And it uses a very crude decimation-by-numbers system for it.

 

2 hours ago, arton Rotaru said:

And since  people made entire 1 prim bedrooms and whatnot out of them, instead of rather simple organic shapes they were intended for, the LOD rule didn't work out indeed.

I don't know. I'm not particualrly fond of rocks that suddenly change shape as yu aproach them either. It's .... eerie.

[arton Rotaru]

23 minutes ago, ChinRey said:

That was actually quite early - 2012

The mesh closed beta started in 2009 IIRC. I jumped in on October 13th, 2010 when the public beta started. At this point anybody, including Moles could have attend the meetings. I guess Moles could have been in the closed beta already, if they wanted. They and LDPW might have been working on something else at the time though, IDK.

23 minutes ago, ChinRey said:

One example: I measured a kitchen chair 0.5x0.5x1 m...

Yes, but it doesn't hurt the land impact that much if you keep the medium LOD the same as the high LOD with such little objects. Because, the lowest LOD will have a great reduction effect with them. So all in all it's a quite flexible system to achieve decent results IMO.

 

Edited June 11, 2017 by arton Rotaru