Mesh 3D Logos - Is this as good an LI as I could expect?

[Toysoldier Thor]

I have been working in Zbrush & Shadowboxes to create 3D logos created in Photoshop.  Inside Zbrush I can make these 3D models look amazing, but I want to be able to efficiently bring them into SL.  I have tried almost every trick to reduce the polycount and then use normal maps to hide the very low rez model that comes into SL.  I have deleted all poly's from the back of the 3D model and the model you see in this post is only 2100 poly. 

I could possibly even decimate it down to just under 2000 but then thats about as low as I can get.  When I upload the DAE into SL, the model uload metrics dont even start at the 2100 poly that I saw in Zbrush.  I made teh physics use the LOWEST LOD.  But as you can see in the 2nd clip, the best I could get is a LI of 25 for a ~ 5m long mesh.

Sooo is this about as good as it can get for a mesh of a logo like this or is there something fundamental that I could get this mesh far smaller?

 

[Gaia Clary]

Your image looks like you have used flat shading for your meshes.maybe try to use smooth shading instead ? that should reduce the LI significantly.

A quick check would be to enable "Generate normals". Although you may later want to do that in your 3D editor so you have better control over which faces will become smooth shaded.

I must admit that the terms "flat shaded" and "smooth shaded" come from blender. In your 3D tool this might be named differently (maybe someting along "use vertex normals" vs "use face normals" )

[Drongle McMahon]

I can't read the dimensions clearly from your picture, but it looks like it might be about 5x2x2m. This gives a "radius" of 3. At that size, the low (3rd) LOD may have a significant effect on LI. So you might do better not making it the same as the medium LOD. Also, after you use the smooth shading as Gaia says, not only will that reduce the LI of the present mesh substantially, but it will probably let you simplify the mesh further and still get good results.

[Toysoldier Thor]

Well stupid me.... thanks Drongle for pointing out the major factor... I had a brain fart when I thought that by making the LOWER LOD that of the MEDIUM LOD that it would remove the LOD.  In fact it made the LOWER LOD more costly.

So... both of you mentiond about this SMOOTH SHADING which I am not sure what that is in Zbrush unless it is the parameter during the Zsculpty export where it asks if you want to enabling SMOOTHING - I said no.

So I did an experiment based on what Gaia suggested.  I went back to the beta grid and I uploaded this same model with and without "GENERATE NORMALS".  All other parameters were set identical for a model that was about 5m long.  At this res size, the Normal model was LI=9 and for N-Normal model it was LI=10.  Saved one prim.  I will say though that the NORMAL model looked much smoother than the NO-Normal. 

When I increased the Logo model to 15mx4mx1m,  the Normal was LI=53 and No-Normal was LI=57.

As such the Generate Normals helped a little bit for LI efficiently but Generate Normals made the model look better.

For me.... I really dont like the quality of the Logo at such a low poly count (looks meh for me and I wished I could use a higher poly count.  But what are others opinions... for a logo like you see in the OP... what kind of LI would you expect for a nice quality mesh if it was done efficiently?  Am I in the ballpark of LI=9 for a 5x1x.5 

[Madeliefste Oh]

You can get you mesh much more efficient when you don't let SL generate the LOD 2, 3 and 4, but do it yourself. When you make your own models for these lower level of details and upload them, it going to safe you a lot of prims.

 

Our logo, size about 5 x 0.6 x 0.2, land impact = 3. It was not even optimized for low prim count.

[Kwakkelde Kwak]

I'd also advice to stop using the auto-LoD calculation. On the lower LoDs you can get away with a plane easily, since the logo is almost flat, bringing the polycount of those LoD models down to 4. (or 5 really since you'll need a spare triangle for the higher LoD material.) I think you'll be below 5 instead of 25, plus it will probably look better from a distance from almost all angles.

Take a screenshot of your model in photoshop or zbrush, looking from the front or back. Add a transparancy mask and use that for the lower LoD models.

[Toysoldier Thor]

Made,

I understand what you are saying and the post of Kwak's as well but I didnt actually use the auto-generated values of LOD from SL's import. 

In the last revised upload I did after Dronlge pointed out my brain fart of matching the Medium and Lower LODs, I let the other LOD's be auto-proposed to me by the utility and then I changed the LOWER and LOWEST LODs dramatically - although from what Kwak posted - maybe for this logo I should have been even more aggressive.  I set the LOWER to 100 and LOWEST to 25.   I guess as long as no avatar will likely view the logo from far enough away to engaged LOWER and LOWEST LOD - I could set these LODs to both 10 and 5.

I looked at your logo Made and from the photo it looks like your Logo would be allowed to be nore effecient than the logo was was modeling since it appears you are using sharp corners and flat sides.  This would allow for much better decimation than my logo which is made up of all analog curves.  The surfaces of my logo has almost no flat runs on the surface.  Also, my logo is a bit fatter and taller than your logo at the LI you mentioned.  As such, the fact that I am now at about LI=9, I suspect I am getting pretty close to what would be expected to be a good LI for an analog shaped logo of similar size.

 

[Toysoldier Thor]

Hi Kwak,

Just further question on your suggestion... I sorta know what you are saying but that technique you mentioned... are you suggesting to create an extremely low flat surface LOD model?  In Zbrush I think I could just uses a plane "tool" and decimate it to extremely low poly.  BUT my quesiton again is, would this not be the same as me changing the value of the LOWER and LOWEST LOD metric proposed by the SL Upload utility to a poly count of 5 and 3?

 

[Madeliefste Oh]

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Toysoldier Thor wrote:

I looked at your logo Made and from the photo it looks like your Logo would be allowed to be nore effecient than the logo was was modeling since it appears you are using sharp corners and flat sides.  This would allow for much better decimation than my logo which is made up of all analog curves.  The surfaces of my logo has almost no flat runs on the surface.  Also, my logo is a bit fatter and taller than your logo at the LI you mentioned.  As such, the fact that I am now at about LI=9, I suspect I am getting pretty close to what would be expected to be a good LI for an analog shaped logo of similar size.

 

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Yes, you are rights. Your has more letters as well, so yours will lead to a higher prim count... but three times more seems very much to me.

 

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Toysoldier Thor wrote:

Just further question on your suggestion... I sorta know what you are saying but that technique you mentioned... are you suggesting to create an extremely low flat surface LOD model?  In Zbrush I think I could just uses a plane "tool" and decimate it to extremely low poly.  BUT my quesiton again is, would this not be the same as me changing the value of the LOWER and LOWEST LOD metric proposed by the SL Upload utility to a poly count of 5 and 3?

 

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Yep, the lowest can be a plane with four points, if only the frontside must be visible from a long distance. When also the backside must be visible, you can copy this plane, reverse one the normals, and then link both planes.

This would not be the same as changing the value of the poly count in the SL uploader, because the SL uploader cannot think. It cannot analyse the situation you put in front of it. Or it anlyses it only as 3 dimensional object, and won't come to the conclusion that 'flat' is the best option in this case for the lowest LOD. It will make the 'cheapest possible' 3D representation, with leads often to very heavy distortions on the mesh from a distance.

 

[Kwakkelde Kwak]

It is nothing like it.

If you decimate or in any other way reduce your model to 4 or 5 triangles out of the somewhat complicated model that is your real 3d logo, you will have 4 or 5 random triangles. That will most definately lower your landimpact, but it will look like, well, 4 or 5 random triangles.

If you purposely build a plane, with a screenshot of your model on it, it will look better than a 90% or even 50% reduction in polycount from a distance probably, but at a fraction of the geometry. The only thing that will be missing is true depth, but that's hardly noticable from a distance.