Assign material issue? What is this?

[Honey Icechant]

Hi everyone!
I use to add more faces  to my meshes, and after uploading them to SL, i color each face to see if its ok. 
I did the same with this oval table. 
In Blender everything looks fine. But when i colored that table cloth in SL, the color didnt apply to all faces. I had to click on those and color them too.
I never had this problem before. I had some double verticles that were removed, but that didnt help at all. 
This is a one sided mesh.
Do you know why is this happening and how can be fiixed?
 

[Chic Aeon]

OK. I see on rereading that this is ONE SIDED mesh so what I wrote below is wrong. It looks a bit like a phong issue but we aren't seeing that these days so I think that was fixed and that was about "double sided" in a sense too -- so that's not it. 

Hopefully someone will have an idea. Did you try uploading it more than once, just in case the uploader had an issue on its own? 

Edit AGAIN:  I had a thought. What happens if you only have one material assigned to the whole object? Do the same tris not texture?   It doesn't really seem like a materials issue to me, more of a problem with the mesh. So just wondering. The beta grid is your friend in cases like this.

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Is your table cloth bottom double sided (like with a solidify modifier)?  If so and the yellow there is the underside of the cloth then the faces are too close together and you need to increase the distance between them or  get rid of the underneath layer  altogether as it looks like you don't really need it anyway. Or perhaps just the part near the floor needs to stay. 

IF coloring ONE of the yellow triangles colors them all, then that is what I am thinking about.  

Other than that, no other ideas  

Edited July 24, 2017 by Chic Aeon

[Honey Icechant]

No, its not double anywhere, its one sided obj, that's why i got shocked a bit when i saw this  

[Chic Aeon]

2 minutes ago, Honey Icechant said:

No, its not double anywhere, its one sided obj, that's why i got shocked a bit when i saw this  

Yes, I figured that out and edited a couple of times.  LOL.  See my revised post. 

[Honey Icechant]

Yes, i uploaded it 3 times, because i needed to find the balance (Li, LOD), same issue.
It has Lamber applied  on each face btw.
AND, i uploaded a table now with a single material added to the whole obj, the problem vanished. So it must be a material issue, but what kind... ? I need those faces

[Honey Icechant]

I deleted the old cloth material, then assigned a new one to that face - same, Lambert - same issue, but not on exactly same number of faces, some are missing.

(The pink one is the newest upload withe new cloth material)
This gets more and more weird

[arton Rotaru]

Your cloth has more than 21844 triangles, and is exported from Blender.

[Chic Aeon]

Well I had no idea what a Lambert is but looked it up and that doesn't SEEM like it would be the problem. Notice that the pink one has LESS (most importantly not the exact placement plus a couple of new tris not on the green.

Sorry, I won't be any help.  Hopefully someone who has seen this before can give you some advice. 

I wish you luck!

Ah I see arton has replied. Maybe the answer is there!   

[Chic Aeon]

1 minute ago, arton Rotaru said:

Your cloth has more than 21844 triangles, and is exported from Blender.

Well I thought of that but when I had that too many tris issue (fleetingly and hopefully never again) I had NO problems  like this at all, only that the physics wouldn't work correctly. One of mine was cloth too (nasty culprits). 

So if the number of tris is the issue, then dividing the mesh in half and uploading as a linkset might work. 

A better plan would be to get rid of some of the topology where it isn't needed. 

[arton Rotaru]

5 minutes ago, Chic Aeon said:

Well I thought of that but when I had that too many tris issue (fleetingly and hopefully never again) I had NO problems  like this at all, only that the physics wouldn't work correctly. One of mine was cloth too (nasty culprits).

The problem with more than 21844 is still that the importer creates a new material for the remaining triangles on it's own. That's only the case for collada files which are referencing geometry in <polylists> like Blender does, rather than in <triangles>.

I'm quite certain you know this as well though, since it came up on the forum a gazillion times already.

[Honey Icechant]

Indeed, Arton, but when a single material is added to the whole object, the tris number is the same and this issue is not present. 
I will try divide the mesh too, Chic. 

Acutally i dont like this table, i reduced the polyount of the original model, so as you see, this one is not so nince, 
I will make a new model, that will be more detailed, at least it will look as i wanted   and divide it, then we will see what happens
Thank you both! ♥

[Aquila Kytori]

As Arton was replying I was doing screenshots, I'll post anyways

Test upload with a plane which has a  triangle count of approximately 23.000 in Blender and has a single material assigned to it.

 

Quote from  http://wiki.secondlife.com/wiki/Limits

• The 64k vertices per material is pre-empted by a limit of 21,844 triangles per material, which is presently reported as BUG-1001. (4/2014 - See discussion page)

 

The import process will continue making new materials beyond 8 x 21,844 (=174,752) triangles, but the extra triangles then get dropped by the limitation to 8 materials, causing holes in the resulting object. Over the 21,844 triangle limit, the vertex count will start to climb steeply, even with smooth shading, because the materials get highly interspersed. So the same vertices have to appear in multiple material lists. So the moral of the story is to stay below 21,844 triangles per material, for now, if you want to avoid some unexpected effects.

Since viewer release 3.8.4, processing of meshes in the Collada file that have faces assigned to more than 8 materials has changed. Instead of simply dropping the extra material faces, the uploader now creates a new object to accommodate them. The result is that the single mesh is divided into multiple objects (prims) in a linkset. Thus the limitation to 8 materials is removed as far as input is concerned, but still applies to each of the resulting linked objects actually uploaded. As a consequence it is now possible to upload a mesh with more than 174,752 triangles, although it will be divided into multiple objects.

Edited July 24, 2017 by Aquila Kytori

[arton Rotaru]

41 minutes ago, Honey Icechant said:

Indeed, Arton, but when a single material is added to the whole object, the tris number is the same and this issue is not present. 

That sounds strange indeed.

If you really, really, really need this many polygons on your model, I'd recommend you download the free, standalone Autodesk FBX Converter 2013.3, export your mesh as FBX from Blender, and convert it do DAE with the FBX converter. Exports like this won't have the 21844 triangles per material limitation. (There might be still a similar limit, but it would be much, much higher than 21844 tris. (Look Drongle, I try to include that in my replies as well  )

This way you keep it as one asset, rather than splitting it into multiple assets, which isn't beneficial for performance. Same goes for multiple materials, if you have multiple materials on a single mesh, the mesh will be split into multipe meshes in the render pipeline.

Edited July 24, 2017 by arton Rotaru
Typos

[Honey Icechant]

You guys are so awesome, so big help
I knew that having more than 8 materials divides the object, i had a mesh like that.
And now i know more, tris over the limit do the same....

I want to make detailed meshes in the future, drapes with tons of folds and ruffles, as i always wanted to, but these limit issues pushed me back from trying until now.
I have to find new solutions, so i am grateful to all of you for tips & advices, for the time and patience you put in these replies! ♥

Edited July 24, 2017 by Honey Icechant

[Chic Aeon]

37 minutes ago, Aquila Kytori said:

So the moral of the story is to stay below 21,844 triangles per material, for now, if you want to avoid some unexpected effects.

OK. So the reason that MY ohtoomanytrianglesmesh didn't have this issue is because I had two materials (underside of cloth and top side) and the poly count was JUST over the limit for the whole mesh. Hence I didn't run up against that extra material added issue --  as I was well under the limit per material.

And yes, I did "know" this arton LOL, but honestly unless a problem has affected ME it isn't etched indelibly in my brain.  I will make an effort to REMEMBER it this time. Better yet, let's just get everyone to make lighter mesh. Since mine are typically around 5000 or WAY less, I just don't run up against this often :D. 

And yes, for sure, you guys rock

 

And @Honey Icechant Those meshes that you often see (some of them early on and still out there selling) are WAY to heavy a mesh for a game asset. Even my dropped cloth (a beautiful accident that I just wouldn't discard even though I knew better) was more than it should have been. I was in one store with examples on display and my very hefty computer DIED IN THE WATER and framerates went down to like 5 and I had to leave.  So there IS a reason why things get difficult to make in higher polycount. It is a BIG HINT that you shouldn't be doing what you are trying to do 

 

If you must make what you want to make, try making your high poly model and baking the textures (if you do that) and THEN get in bed with the decimate modifier (not my favorite as I personally believe in keeping things lightweight from the beginning) because once you understand it well, it CAN help with what you want to do. Just be sure and do it AFTER you have your final texture bake.

 

 

[Chic Aeon]

1 hour ago, arton Rotaru said:

The problem with more than 21844 is still that the importer creates a new material for the remaining triangles on it's own. That's only the case for collada files which are referencing geometry in <polylists> like Blender does, rather than in <triangles>.

I'm quite certain you know this as well though, since it came up on the forum a gazillion times already.

OK, See my comment below *wink*.   "Know" and KNOW are sometimes different things in my world. Happily I have never had this issue and since I don't plan on ever GOING there, I do have a tendency to ignore the info ^^.  Bad girl. 

[arton Rotaru]

Sorry for being off topic, but while searching that bad girl image, I came across this image as well. It cracked me up.

It's a Lipstick.

[Honey Icechant]

I understand you well, its a big-big pain of mine (the other is the alpha glitch when 2 semitransparent surfaces overlap eachother)
 that i cannot make what i imagine look exactly how i imagine it.
I know those methods you mentioned, and use them, i make curtains and i do everything i can to not exceed the 5 Li with a curtain.
Visit my store and inspect them
BUT sometimes i have (and want) to make really nice, smooth and detailed objects, like big wedding tables - custom request.
You cannot make it less verts if you want folds and folds and folds and.... and richly draped, curved stuff.
So, sorry, but here is the next
23790 so far - a little bit reduced by hand - and it would still need 1-2 more egde-loops on top part to be really nice,
plus i originally wanted the inner - almost straight cloth to be double, like 2 semitransparent tulle layers... plus runner..

These will be separated objects anyway.