One Prim Plants - Secret Lag Monsters

Sculpties are essentially a rather severely limited subset of meshes with low-precision vertex specification. We should avoid the expectation that the introduction of more general meshes will magically solve everything.

Meshes will allow more efficient storage of more geometries with less wasted polygons, but they will certainly take even more bytes per vertex (three floats (2?4 bytes each) vs three bytes). Meshes can easily have as many or more polygons than sculpties. It all depends how they are used and what limitations are placed on that use.

Meshes will still have LOD problems, the accompanying texture stretching problems, and collision boundary problems. Whatever the collision model, unless it is as simplified (and useless) as that of sculpties, that will be a large extra load on the server, not just the client.

I suspect that meshes will either have to be so limited that much of the expectation will be disappointed, or they will herald a wholly new scale of lag monstrosity that will only be slain by a few more iterations of Moore's law.

Low precision? They seem pretty precise to me, if you know what you're doing, and your exporter is any good. Sure, not high detail by any means, but definitely capable of being very accurate representations of the original model.

There are only 8 bits for each coordinate within the bounding box. This limits the accuracy of vertex positions to about 1/256 x dimension, or about 0.04m for a 10m dimension. In some respects, that is accurate enough, but for making non-perpendicular straight lines or flat surfaces, it means inevitable kinks except for very special cases.

Yeah lets get rid of color too or at least reduce all textures to 16x16

I just sculpted a 16 8 planes plants x 1 prim and a 32 4 planes plants x 1 prim,
they render fast like a sculpted rock, maybe I don't see the difference becouse my PC is only 3 years old?

Tiziana :
you forgot to mention how many tri polygons are in your sculpties. This is what we are talking about here. The hidden and lag creating extra and unneccessary geometry in one prim sculpty plants, burdening the SL 3D engine

Before sculpties the culprit was the torus. Too many of those in any build and you would begin to lag. Everything with moderation is best.

The policount is not much of an issue , This is not what is causing lag , the main things that cause lag are textures and its abuse.

The textures used usually on Secondlife are of the size of 1024 becouse everyone sells their items to make them lookat their best , but items usually have also severall textures so just pick an avatar with an item that uses severall textures and is alredy filling a part of the memory resources . One texture of 1024 is around 4 mb and 5 mb if has alpha , no matter of its texture format type used , so take severall textures of 1024 , lets say like 10 textures used on an object of 1024 means about 40 mb if someone has a video card with 256 mb then the math is easy to do ..... and since SL downloads all the textures in sight and they arent optimized so that at distance they use mipmaps , or reduced size ones , they overload the cache and thats why it needs to be cleaned one in a while .

So what lags arent polygons , unless you use millions , but are textures , also physical objects influence couse they imply calculations of collisions and reactions .

Also more imprtant is that people think that all sims are the same and that they have to expect everywhere the same efficiency of the game .....

the truth is that some sims are just a collection of boxes with a plain texture repetaed severall times, and this dont lag , so ppl can use long draw distance, when thy enter a sim with heavy graphical design like mine for example tey lament lag , but they don't think that they should just decrease their drag view to improve the experience....

Like others sculpts.

How many tri poly have a sculpted windows, chair, diamond, table etc etc made using a 1024 faces mesh?

It's better 100 sculpted plants or a 300 prims sculpted hairs with 300 resizers scripts inside?

Naiman :
So I see you are in the 'ok so far' camp.

I have read that the activation of shadows is imminent for SL. When this happens every polygon WILL count. The SL engine will have to calculate appropriate shadows for every single polygon.

Also, I believe there is some talk, long term, of material shaders. Again this means that the material will have to be calculated for every single polygon.

So every single polygon will count and redundant polygons like we see in one prim plants etc will create millions of unnecessary calculations because of the millions of unnecessary polygons.

MORE polygons BAD, LESS polygons GOOD !
Redundant unnecessary polygons, very bad !

it's already happening.
http://my.opera.com/boylane/blog/

And, personally, I don't see much more slowdown from sculpts than normal prims, when it comes to shadows.

Lets just call to halve the number of polygons in the avatar mesh then

I didnt say is good , I said is not bad as its beeing said , whats bad are textures , couse arent optimized , poligons more or less are optimized by distance , also , I have a pretty powerfull machine and I have no lag at all , when shadows will be implemented for sure will be an optional feature so people shouldnt lament if they will enable them when their machines can't really afford to handle them ... not all pcs are the same ....

They're doing it through pixel shaders in the nVidia 8xxx and 9xxx GPU. If you have an ATI or an older nVidia GPU, or a Mac, you won't get any shadows.

We already have material shaders, they're just indirect and hidden behind options like glow, full-broight, and shiny.

And finally, SL does no polygon optimization at all, so every sculpt has the same number of polys whether it's a couch cushion or 64 blades of grass. And when you look at someone with 100 prim hair you're already handling the same number of polys as a sculpty for every prim torus in their hair.

There are good and bad 1 prim trees

To make these shapes involves using a couple techniques of precision mesh editing and burying faces of the sculpty. I use Blender, and Domino's wonderful scripts to make a variety of face counts of the trees in several configurations. It took tons of experimentation to find the best way to fix alpha sorting issues and LOD balance the trees (shameless plug).

Many of the best sculpties lately i have seen use the broken up technique with some disadvantages that it loses much of the texture space on the UV map.

I think 1 prim tree sculpties and others that you see with loading problems can affect perceived client lag, either an un-graceful preload as is clicks through the LOD levels, or a fudgy moment when SL cannot figure out how to render the sculptie. This has been known issue with sculpties in the recent viewers so should be fixed i guess. Some sculpties are better than others, its pretty evident. This technique is a bit of a hack after all.

There are 2 ways to think about sculpties either making or shopping for them, I think of it as a 'graceful lod' or a 'fixed lod' approach.

A graceful load will not look the same through the LOD or load times but will resemble the final fully rezzed sculpty and still be pleasing enough too look at while its loading. An ungraceful sculpty will look all messed up and not even like the final rezzed object as is common with these kind of sculpties.

A fixed LOD will retain the same shape in the levels of detail above it and is best for these kind of sculpties.

A sculpty baked at lower level of geometry ( i think 4x9 is the lowest if I remember what Domino said) holds its shape through all distances or prim sizes and would be 'fixed' texture wise what i would say is true LOD 0 . I have several examples of these but its limited in the number of faces you can use.

Performance wise I would imagine that 1 prim version correctly made would represent less overall lag than 3 planes with 3 main texture calls (plus transparent edges so 6 texture calls each) .. as opposed to repeating 1 texture over the entire shape repeating over 16 or 32 faces.

Now for the big bonanza throw in the oblong sculpties in to the mix and now there are alot more options for minimizing geometry for simple objects! I have noticed a longer than normal first time load for oblongs sculpties that may affect perceived lag. No pain no gain..

Yes sculpties are a pain.. there I said it, but I think the end result is worth it as they have changed the face of of SL. Adding mesh support at this point might be the catalyst that completely shuts out the hobbyist/ fun builder from making any scratch at all, sculpties provide a fairly easy, compact and proprietary way for SL to improve thier content quality overall. With flexi sculpties its promising, but one thing i would love to see first is sculpty mesh collision rather than the ridiculous bounding box.

-whyroc

(Probably my question belongs in Building Tips, but as long as we're here now...) This comment intrigues me; why would meshes be any more difficult for the hobbyist to create and import than are sculpties? Or is the focus on the proprietary nature of sculpties, largely preventing the import of pre-existing models developed for other purposes, thereby leaving a niche for SL-only hobbyist development? Or something else entirely?

yes sculpties are a real pain and restrict us all creatively in many ways.
We are so used to the SL way of doing things - it's like we're all in a trance

Sculpties have been a fun and interesting halfway house, but they make us do the dance and jump through many hoops, unnecessarily. They are actually really hard work compared to working with mesh. LL are trying to re-invent the wheel when the wheel already exists.

Mesh import will herald a new era of creativity. If you think sculpties are good, wait till you see what people will do with mesh import - hobbyists and experts alike. And for the record, mesh modeling is way, way easier than dealing with sculpties for everyone, whatever skill level you are at.

1. We need mesh import
2. We need tri polycount limits for land
3. We need tri polycount limits for avatars

Optimised mesh based worlds will allow several 100 people to be in the same location at the same time - live events, RP, corporate meeting, lectures etc- that's a killer feature for any virtual world that is about social networking and interaction in a 3D space

SL can't do this right now and the way it's heading with e.g. poorly optimised sculpties - 'some' 1 PRIM PLANTS being a good example of this bloat - SL will not be able to compete with the kind of technology that's on the horizon

I am still somewhat surprised that LL are interested in attracting business and Corporates to the SL platform and yet do not have mesh import.

I so love SL, that's why I started this thread, I want it to succeed and go mainstream but I have concerns for it's future.
We must surely look forward and not just at 'the now'.
The TAO of 'ok so far' sort of worries me.

LAO TZU
"The master of the Tao anticipates things that are difficult while they are easy, and does things that would become great while they are small. All difficult things in the world are sure to arise from a previous state in which they were easy, and all great things from one in which they were small. Therefore, the sage, while he never does what is great, is able on that account to accomplish the greatest things. . . . "

Thanks Ting. I learn so much reading these kinds of postings. I don't know what good it will do me in SL. Maybe before I buy something I should look more carefully than just an 'edit - prim count' to see what effect an object will have on my land, where I am certainly having a lag issue.
BT

What is Mesh import? I have been learning a little about 3d by trying to learn Hexagon. can most of the programs that create 3d create mesh objects for SL?

BT

A concern I have for mesh support is the length of time it could take to download them.

I know lossless sculpties can take seemingly forever to appear. Although I have a feeling that this is caused by a texture cache bug rather than a bandwidth limitation on LL's end.

Yes, Second Life will be able to load objects (aka meshes) made in other programs.

This is assuming Linden Lab are actually adding a mesh import option. I've not actually seen a Linden say that this is going to happen.

Bhakta :
Hexagon is a great 3D tool and any time spent learning it will not be wasted as the basic skills learnt in Hexagon will easily translate to more fully feature pro 3D applications.

and the answer to your questions - what is mesh import ?

mesh import is heaven
basically it mean you can use external 3D modeling tools to create models/meshes and import/load them in to SL and other virtual worlds which will support mesh import

I would say keep developing your SL building skills for the now but also keep improving and learning Hexagon 3D as it will help prepare you if you want to be a content developer for other virtual worlds in the future