Can Mesh objects be linked to prims prim count went through the roof

[Tonimonastroniboni Oh]

Hi,

I'm not a mesh builder. I purchased mesh objects and I did not resize them in any way. They showed a land impact of 4 prims. I then linked them to other mesh objects and other normal prims. The prim count on one of the linked items went from 9 to 680 prims. What am I missing here? Can you link a normal prim to a mesh object or link multiple mesh objects together without the prim count going through the roof. Example I bought a mesh camel (4 prim land impact on it's own) I then linked it to some rope normal prims and a barrel which totalled 5 prims. If I rez that linked set at a SL sandbox it now shows as 688 prims. I don't get it. I did this today thinking there was an SL issue yesterday and same result. Can you not link mesh at all? Any explanation would help.

Thank you,

Tonimonastroniboni Oh

[Erik Verity]

Mesh can be linked to legacy prims, but it does cause the prims to be converted to the new accounting for Land Impact. This is no problem as long as the prims consist only of simple boxes or cylinders (this means only resizing and even stretching - none of the options from the right side of the edit window can be used - hollows, path cuts, etc. are torture affects that will make their LI skyrocket).

If you have anything other than a simple box or cylinder, you will need to change its Prim Type from the Features tab of the edit window to Convex Hull or None to prevent this. Convex Hull will not allow any interaction with 'holes' or indentations of any kind - it will just appear to be solid. None will give the effect of being phantom. If those options won't work for you, then you will have to avoid linking those prims to mesh. On the other hand, if you can change the Prim Type and everything works alright, you can actually see LI get lower compared to the number of individual prims in the link set.

 

[Frawmusl]

Er.. Another thing
When you link a mesh to another object the mesh becomes larger to SL, Meaning the higher level of LOD is seen. If the original creator made it for the mesh to be X size and the LOD is greatly reduces to decrease the LI and you take the mesh, and make it larger (IE linking things) it will use a different LOD to determain the LI, So if you have a small item and link it to where it is a medium size the Low LOD typically would determain the impact, but now its medium determains the impact and the creator didn't make/account for medium LOD then the LI will shoot through the sky

[Erik Verity]

I cannot go in-world right now to verify exactly, or specifics, but I believe that is incorrect. I have created mesh objects, specifically to be individual links of a set, purposely sized to have correct LOD behavior individually. In fact, I am sure I have had smaller links that broke down gracefully as intended even though connected to a larger whole.

It has also been my experience that LI was greatly reduced by creating individually smaller pieces and linking them together instead of uploading a single, high-poly, larger sized mesh. I'm sure there are more factors involved than simply being able to say one way or the other what will happen, but I am pretty sure the LOD behavior is dependant only on your LOD uploads, size, and distance for each individual link. I will test again specifically for this, but honestly, there is a reason for different LOD models for each mesh upload.

I have also seen and been asked about entire buildings that have had poor LOD breakdown noticed from a little distance. This would not be possible unless individual links (created without adequate LOD uploads), retained their separate LOD behavior.

ETA: On another note, there have been plenty of cautions and guidelines in this forum alone for linking prims to mesh; The PRIM TYPE of the primitives and resizing has always been factors we are told to consider. I have never seen a warning before about the size of the entire set caused only from linking, and have never seen it have an effect first-hand.

[Erik Verity]

Ok, I won't even bother to edit the last reply, I'll just conclude it here:

Most mesh I have created was done specifically to have reasonably low LI, which means there are limits to how large and complicated one model can be before there is a huge advantage to having smaller models.

Linking alone has no effect whatsoever on how much the size contributes to LI. Once I have models sized correctly and am happy with their individual LI, linking them never gives them a greater individual LI because of total object size. If anything, it makes total LI smaller.

[Chic Aeon]

Obviously the only way you can KNOW is to try linking (preferably on the sandbox where you won't send objects to the Lost and Found folder).

THAT being said ---- there is indeed a new system of land impact.

MESH and sculpties do not play well together.

If you were linking old fashioned prims (legacy) and got that huge number, they were likely not cubes but some hollowed or otherwise adapted prims. Linking mesh to a cube  (any size and whether "prim" or "convex hull" works fine.

Also I noted just the other day that amazingly I linked a mesh item (say 4 LI) to a prim (set to prim) and actually got a lower count (like 2 or 3). I have NO idea how that worked but happy as it made my total, fairly complex build 46 or so.

ALWAYS test. If it doesn't work then just don't link.

 

Sometimes linking mesh (say an object with LI of 1.4) to other mesh or prims will increase the count (so two 1.4 mesh items that show up as 1 LI each when unlinked will become 3 when linked -- (1. 4 + 1.4 rounded up).

[LepreKhaun]

Under the old (prim & sculpty) accounting, one prim was one prim and this remains as long as it's just prims and sculpties within an object. Under the new (mesh & convex hull) accounting, the highest of three factors determines the Land Impact (LI)- the download weight, the physics weight and the server weight. And this accounting is applied across the board for everything in the object.

 

You can see the potential impact of linking a prim object before you link it to mesh by clicking the More info link in your edit/build panel after you've selected it. Pay paticular attention to the  physics weight as this is going to be the "gotcha!" with any torus and/or tortured prim.

[LepreKhaun]

Incorrect.

---

Frawmusl wrote:

Er.. Another thing

When you link a mesh to another object the mesh becomes larger to SL, Meaning the higher level of LOD is seen. If the original creator made it for the mesh to be X size and the LOD is greatly reduces to decrease the LI and you take the mesh, and make it larger (IE linking things) it will use a different LOD to determain the LI, So if you have a small item and link it to where it is a medium size the Low LOD typically would determain the impact, but now its medium determains the impact and the creator didn't make/account for medium LOD then the LI will shoot through the sky

---

 

[Erik Verity]

---

Chic Aeon wrote:

Sometimes linking mesh (say an object with LI of 1.4) to other mesh or prims will increase the count (so two 1.4 mesh items that show up as 1 LI each when unlinked will become 3 when linked -- (1. 4 + 1.4 rounded up).

---

Now that's a good point I haven't experienced yet - I've realized (and forgotten) that rounding down for a single prim can happen when less than half way to the next integer, but most of the time I would have more than just a couple of prims like that. Still, that is at most a value of 1 or 2 that would be seen going up, as long as the prim guidelines pointed out in this thread (and elsewhere) are followed.

Understanding the limits with complex objects, it is still easily possible to get a far lower LI with multi-link sets by linking and using the new accounting; there is no re-sizing factor applied to an individual link solely because it was linked, nor does its LOD behavior with distance change unless it actually is resized.

 

[Chic Aeon]

Interestingly enough --

I made a complex set of windows with single glass pane. They uploaded as a linkset on Aditi at 1.6 LI. When I deleted the "glass" from the windows set simply to see things better while planning, the window frames became 1.5 LI.  I linked the .5 window pane back to the window frames and I still had 1.6. So THAT is a bargain. *wink*.

 

 

[LepreKhaun]

---

Chic Aeon wrote:

Interestingly enough --

 

I made a complex set of windows with single glass pane. They uploaded as a linkset on Aditi at 1.6 LI. When I deleted the "glass" from the windows set simply to see things better while planning, the window frames became 1.5 LI.  I linked the .5 window pane back to the window frames and I still had 1.6. So THAT is a bargain. *wink*.

 

---

One way to look at mesh accounting is to see the download, physics and server weights as a vector ( "<download, physics, server>" ), with the LI being set by the highest of the three for any given instance. When you link you are simply doing vector addition.

 

So, the way to see it is:

A = <1.5, 0.1, 0.5> (LI is 1.5, being set by download weight)

B = <0.1, 0.1, 0.5> (LI is 0.5, being set by server weight)

A linked with B = <1.5, 0.1, 0.5> + <0.1, 0.1, 0.5> = <1.6, 0.2, 1.0> (LI is 1.6, being set by download weight)

 

Approaching it this way shows how [Edit for correctness] confusing meaningless LI can be without knowing which of the 3 factors is setting it.

[Tonimonastroniboni Oh]

So after all these posts from all of you it's great that this post brought all of these responses. I ask is Linden Labs on crack???

I've built tons of things and enjoyed it. I've even created sculpties learning on my own from posts. I shouldn't have to be told oh ya can't do this and ya might not want to do that and depends on the builder. Wait a second if I buy something on marketplace full perm just I used to before and it says 4 darn prims it shouild be 4 prims. I shouldn't have to find out this way or go to a mesh class to find out oh guess what it could become 700 prims but, you'll have no idea until you waste money buying a product, link it and then find out. And I'm not sure who said it but, "Don't link any then" that's just stupid. I am trying to create a Opera in SL and instead of using mesh which is supose to be OMG the greaest from SL I have to re-purchase all the products I bought and try to find them as sculpties. I appreciate all of your replies but, read them yourselves and doesn't it speak volumes that folks are buying product with no knowledge of this and I've seen no notecard from any seller about this.

SL if it ain'y broke don't fix it

Thanks

[steph Arnott]

If it aint broke, you be still in a pool of slim waiting for the first cell split. Stupid comment, without evolution there no progress

and as an answer change the old prims to curved hull which reduces the load on the server and link the mesh.

[Tonimonastroniboni Oh]

Update on this post and my frustration with linking mesh with regular prims. Objects I'm working with are simple two ropes and 3 barrels all of which are either scuplt or regular old prims totalling 4 prims. I'm linking them to a camels back and the camel is Mesh. In total before linking 9 prims. Linking them without any changes resulted as my post says to 688 prims. After your thoughful insights and knowledge, I changed all regular and sculpt prims to convex hull and result was on their own without a mesh object attached went up from 5 prims to a whopping 80 prims. I then reviewed posts and saw try setting the prim type to NONE. I then changed all the regular prims and scuplts to NONE and then linked them to the camel which resulted in a grand total of 10 prims.

1. I'll do my best to attend a mesh class to learn more.

2. I still will stand by my post that this change should be explained on LOD and linking on every mesh piece sold with an brief description on marketplace to help individuals like myself that aren't mesh builders.

3. The purpose of a forum is to gain help and for all of you who replied I truly appreciate your assistance since many of the vendors who I asked never replied at all. Hopefully my post also helped others as well.

Thank you again!

[steph Arnott]

HMMM would have helped, mentioning sculpts, lol

Added: Unless you did and i missed it. Any how you learned so that a bonus for the future projects.

[artifactsofmars Omegaman]

On 7/19/2013 at 4:00 PM, Tonimonastroniboni Oh said:

Hi,

I'm not a mesh builder. I purchased mesh objects and I did not resize them in any way. They showed a land impact of 4 prims. I then linked them to other mesh objects and other normal prims. The prim count on one of the linked items went from 9 to 680 prims. What am I missing here? Can you link a normal prim to a mesh object or link multiple mesh objects together without the prim count going through the roof. Example I bought a mesh camel (4 prim land impact on it's own) I then linked it to some rope normal prims and a barrel which totalled 5 prims. If I rez that linked set at a SL sandbox it now shows as 688 prims. I don't get it. I did this today thinking there was an SL issue yesterday and same result. Can you not link mesh at all? Any explanation would help.

Thank you,

Tonimonastroniboni Oh

  I had the same problem. Mesh is a nasty mess. When I attempted to unlink it and then delete the mesh, everything linked with it vanished, and it did not go into my trash folder. It simply vanished costing me hours of work. My advice is, unless you know exactly what you are doing, avoid this mesh mess in your builds. 

[Pamela Galli]

Its a little late to warn people not to make mesh builds. (Check the thread date. Also, many have been building with nothing else for six years.)

Edited July 9, 2017 by Pamela Galli

[Rolig Loon]

21 minutes ago, artifactsofmars Omegaman said:

When I attempted to unlink it and then delete the mesh, everything linked with it vanished, and it did not go into my trash folder. It simply vanished costing me hours of work.

Just a guess here, but if you unlinked a large structure in a parcel where you were already close to the L.I. limit, the L.I. of the collective group of separate, unlinked parts may have pushed the total over the limit. Objects are supposed to be returned to your Lost & Found folder when that sort of thing happens, but the servers can be overwhelmed and either shove them to <0,0,0> or lose them entirely.

In any case, Pam's right.  This is an ancient thread, hardly the place to be posting a "me too" response.