is there a catch to mesh?

[MoiselleErin Teardrop]

I am just learning how to do it (using blender)and recently built a stair case railing. Seems like a sweet deal, one prim instead of 8 (at least in my case) It is just one texture, material, and color so no problem there...

Aside a couple minor buillding errors like rotation angles and alignments (both my fault), iit seems to work fine.

So anyways, what is the trade-off with using mesh that may not be evident to beginners?

 

It is kind of like when you think you are getting a good deal on a used car or old house but then a week later something goes wrong that you could not have foreseen. having a nice object of oone primm instead of several just seems too good to be true.

[VanillaSunsets]

There is a downside to every form of building. That's why I sometimes "mix and match" the tools we have. At times a prim will be best, at times a sculpt (tho I use those less and less) and sometimes mesh is the best option. No need to stick to just meshes. 

There are a few catches to mesh. First of all, LOD building is important when you use mesh, best is to build your own LOD's. This will prevent the collapsing of your object at a distance. Playing with the LOD's can make a big difference in the LI. It can also ruin it, especially for ppl that have set their LOD to a low number. 

Mesh needs physics to make it possible to for example walk through a doorway or on a floor. To prevent walking through walls etc. Again, there are a few options here, build them yourself or let the uploader do it for you. Sometimes building them yourself is better and sometimes, once you figure out the uploader settings, that is the way to go.

What settings are best depends on the size of your mesh and whether you want them to be seen from a big distance or if they are used just indoors. Indoors you can get away with a low LI most of the time by having very low LOD's. 

There is just no easy answer to your question. Too many variables to just have it boil down to one answer. Once you get into making mesh it is important to watch a lot of tutorials and read many posts here on the forum. For more general building questions you can also search for Blender tutorials and fit that what you learn into the pipeline Blender to SL. 

Medhue just made a very clear video explaning LOD here 

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Here is a video that walks you trough SL physics by Elenora Newell 

Making mesh is a trail and error path, you will probably make some mistakes in the beginning and yeah, you probably will change your workflow a few times coz you find a better way to create something. Have fun building!

 

[Chic Aeon]

** General Reply **

 

The only real downside to mesh IMHO is the learning curve. It takes a long while to learn the tricks and make things "correctly" (note that the term correctly means different things to different creators). Learning Cycles Render is even more time consuming and as one creator I know said "it's like leveling up in a computer game".

 

Once you pretty much understand the program (over 10,000 hours of practice for me but I may be much slower than some) then it DOES become a real pleasure as you can make most anything you want. Prims are still viable for many things and of course take lots less time. But land impact wise mesh will most often win.

 

I was never fond of sculpts because of their loading time (and the ungliness along the way) AND their stress on the server - viewer). I have a few sculpt plants purchased from others still but that's about it. Wearing a piece of sculpted jewelry and turning on the avatar rendering cost data is pretty much an eye-opener.

 

So keep working at it, TEST often -- especially at low LOD settings on the viewer -- and make lovely things.

[Pamela Galli]

I run into all kinds of catches. The other day I made a simple wall with a doorway in it, but it was thinner than .5 m so it reverted to convex hull from prim, so I made it a little thicker, and it went to:

26,000 LI.

Yep.

[Johan Laurasia]

The trade off is efficiency.  Mesh is more efficient than SL prims.  The reason SL prims are less efficient is because of "ease of use".  Take a cube for example.  One can create a cube by defining 8 vertices.  In a program like blender, you can unwrap the UV map and make it flat, texture each face, and bake 1 texture to skin all 6 faces.  SL on the other hand allows in-world editing, so to be able to reference a single face, you need to define 4 verticies  per face (times 6 faces = 24).  So an SL prim has to manage 24 prims, and up to 6 different textures, whereas Mesh has 8 vertices and 1 texture.  You also full vertex control with Mesh, and you don't with SL prims, so you (at times) have to use more than one prim linked to other prims do create a shape that, in Blender, can be done by pushing around verticies.

[Chic Aeon]

LOL. I think that is called an "issue" and we can't really blame that on the mesh but on SL's rules .  I agree that strange things happen. Even within Blender there are oddities (I am guessing actual bugs in some cases). The newest one with bug fixes, seemed to trade off some bugs for others.

 

Since I am SO VERY PLEASED with the improvements in Cycles Baking (maybe Render baking too, IDK) I will just work around the Blender issues.

 

The SL uploader has seemed pretty cranky this last week or so (about the time we got the new prims but have no real reason to believe one thing has to do with the other). I had something that came in at 1 on the beta grid and that exact same file with the exact same numbers in the LODs and the exact same physics wanted to be 6 or something because the lowest setting wouldn't go down to 2 (the lowest it could be). Instead it wanted to be 60. Well obviously that was NOT good.

 

I tried a couple more times and eventually got the main grid to match the beta grid. So it worked eventually, but frustrating for sure. I make buildings all the time with thinner walls and doors and never have that issue (I remember when it came up a LONG time ago). I use cube physics models so maybe that is why.  

[Chic Aeon]

I generally agree with that and that is my base position. BUT, I was educated by a long, lenthy and loud thread a few months ago.  If I have it correctly, while mesh is more efficient in terms of vertices (the texture argument doesn't really hold the same weight for me since while you CAN assign all faces and bake, mesh often has more than one texture face (material) assigned to it -- PRIMS are actually better for first time loading because basic prim recognition is built INTO the viewers.

 

This doesn't work with tortured prims, but with prims that haven't been changed other than dimentions and ratios.   So (not my words) an uploaded mesh cube with six materials assigned is no better (and in some people's minds worse) than a prim cube.

 

I will let others argue this if they want to. I already spent way more time on that other thread awhile back .   

 

Well made mesh with good LODs and a physics model is almost always lower land impact than its prim equivilent. The more complex, the more this shows. I think that might be the only Universal statement we can all agree on. And maybe we can't all agree on that even LOL.   

 

[arabellajones]

There is a lot of poorly-made Mesh out there on the marketplace. And I don't know of any way, short of a demo, that you can check a mesh without buying it.

I have just spent a while going through my outfits, replacing some high-complexity boots with equivalents from the Library avatars. One pair of pre-mesh boots ran to about 24k complexity for each boot. One of similar library boots from the newest mesh figures was about 0.8k for the pair.

The complexity number is the same as the render weight, and one of the big factors in that is the triangle count. It's not the only thing, a smaller texture can make a difference, and for something the size of an ankle boot it's hard to get the camera close enough that screen pixels are even close to the size of texture pixels.

Anyone thinking of making Mesh stuff maybe needs to look at those Linden avatars for an idea of what works. I have a suspicion that some people are looking at meshes made for programs such as Poser, which have wonderful detail, but are not made for live animation.

As far as making stuff is concerned, SL is a game.