How to load mesh with minimal weight?

[KennyChidorie]

And good quality LOD.

Something like a cube with few faces.

Non-rigged mesh.

[arton Rotaru]

To achieve minimal weight & good quality LOD you should create the LOD models, and the physics shape yourself.
The details are there: https://community.secondlife.com/t5/Mesh/Download-weight-and-size-Some-graphs/m-p/1057163/highlight/true#M5561

In practice it looks something like this...some boxy shape with few faces...Each of those is exported separately, and loaded in the corresponding LOD slots ...from File.



[IvanBenjammin]

Drongle needs some kind of lifetime achievement award for that post - I've lost count of the number of times I've referred to it.

[Zed Tremont]

About this topic a lot can be written so kindly consider the text below as a first step practicle "how too" guide. To describe all tricks and threads would make this too long and boring for many.

I fully agree with above mentioned and did read the post of Drongle quite some time ago. Really greatful to be informed more indepth.

This is my personal workflow which has proven to work pretty well, quite efficient though time consuming to do well too. Modelling something takes the least time, whatever it is. To handle all the rest behind that can be quite tedious and absolutely not my favourite occupation.

Making a correct mesh include taking decisions in the balance efficiency.

1. Basic decisions:

A. Determine which LOD viewer setting you need/want. Many creators will use 4 as standard. If made for setting 1.5-2 as some insist on will have as consequence that your collapse will happen faster so in many cases your Li will be considerable higher.

B. Determine if your mesh is typically used "indoor" or "outdoor". If indoor is it really wise to make a superstrong LOD if it want be seen anyway since you will see the house but not the objects inside. Use your resources wisely... as always balance...

C. Consider how avatars will collide with the object, in case of architectural use planes whenever you can instead of cubes (4 triangles instead of 12). Consider if you really jump out of the windows? Collision boxes tend to drive your Li up and can be cause of addng quite a bit to your lag. For items set on a floor eleminate the face down, personally I don't think there is need for a collision there, same for the top in many cases.

2. Workflow (personal of course other system might do the trick too)

A. Upload and rez your mesh (in aditi) only LOD3 (high), cam out and see when the collapse happens with prefered LOD viewer setting. I take a screenshot just before the collapse happens.

B. Determine which detail is still valid from this distance by looking at your screenshot. Prepare your LOD2, eliminate whatever is not needed but while doing this keep an eye on your UV editor. You really don't want to take edges on a UV shell away. UV maps have to be stable and within acceptance of the original.

Upload mesh LOD3 (high), add LOD2 (medium) -> rez and determine again when the collapse happens.

C. Repeat steps for LOD1 (low) if necessary, this mostly depends on the size of the mesh and/or if it's a exclusive "indoor" used object.

D. LOD0 (lowest) in most cases not needed, the least number of triangles for this LOD will add fast to your Li. In some cases and mostly in the case of very small object it might be eventually considered.

E. Physics shapes: as already mentioned make them as simple as possible in most case I just use planes (or a cube of which I delete not relevant faces.

You can make Physics shapes visible with Firestorm viewer. Might be other viewers too, don't know

activate your advanced menu via preference

activate you developer menu -> last check under advanced menu

developer -> render metadata -> physics shapes (check it) to return to the "normal mode" just do uncheck again

You will see a colour code:

3 main colours are most seen and most important:

I. blue: your physics shape is considered as efficient or at least acceptable. Verts are not dense for given size

II. orange: verts tend to be dense on at least one spot. You may see that when you decrease the size of the mesh the Li will increase due to the clustering

III. red: your physics is too complex, the verts too dense. I've seen some very bad examples of this where the power of the CPU of the server was completely consumed. You have a serious risk on lag. Few of those on a sim are in my eyes really bad.

As mentioned above this is not a pleasent job to do BUT:

1. you're meshes are as efficient as can be for a given geometry while keeping in mind the detail you want to obtain in the high level.

2. You will barely notice a collapse on the mesh for the given predetermined viewer LOD setting.

3. While keeping an eye on your UV map while preparing the LODs you will have a correct setup of of the applied textures on that distance.

 

As said above the topic is large, influence of several parameters have to be taken in account. Experience will give you a good feel of what you can do and what is to be avoided.

With experience you will/might take the coming steps in mind while making your topology as well as your UV maps/shells.

 

 

[Chic Aeon]

Minimal weight depends a lot on what you are uploading AND the size of the object (size determines a lot in SL with small items costing much less LI wise - imagine you know that. )

 

Just wanted to say that as a user I kept my LOD setting at 4 for many years. I don't believe that was a wise thing to do. Now I keep it at 2 and even though my machine is very hefty, life is much easier with less issues.  I have remade (or actually added higher LOD versions) of some popular products to give folks a choice depending on their needs.

 

I now test at LOD 2 and make my mesh for that setting (the default in Firestorm - other viewers go down to 1.25 to 1) as I am primarily making mesh for the "upscale" market where most folk likely have their settings maxed out anyway. Still, their FRIENDS should be able to see there "stuff" easily IMHO.

 

The best plan I believe is to make the mesh as light as you can while modeling (no multiple subsurf modifiers and the like) and use textures to make things look as good as they can. I make physics models for houses and parts of houses but often use a cube for decor items. I don't like walking THROUGH things which you see a lot of. I would rather bump up against something that is supposed to be solid.

 

There are always decisions to be made and those rely in part on the people you are creating for. If it is just for you -- well then that's easy.

 

Test, test, test on the beta grid.

 

PS. I am happy to see that in the venues I am in, most Home and Garden folks have good LODs these days an objects don't break apart at a near distance. I think we are all learning -- well, most of us .