Mesh tricks for low LI?

[ChinRey]

Hmmm... I have a feeling I didn't explain all aspects of that first lesson clearly enough.

Cleaning up that messy UV map would certainly reduce the LI increase but it wouldn't eliminate it completely. UV islands will nearly always give bigger files and higher download weight than simple symmetric UV maps. And of course baked custom textures are always considerably laggier than repeating ones. That's why Pixar developed the repeting texture system in the first place. (Digression: Why is it that so many people in SL seem to think that techniques like UV islands and normal maps are the latest in 3D modelling? They're not, they're stone age stuff. The reason why they weren't included in the original SL was not that they hadn't been invented yet but because by 2002 they were considered to be hopelessly outdated.)

Don't get me wrong. baked textures and UV islands do have their place and not even the original SL dev team could avoid the completely. I'm also very much for reviving old "outdated" ideas in general. We can learn a lot from studying how the pioneers could work miracles using "supercomputers" with less power than a modern mobile phone.

But in a case like this exmple there'd be absolutely nothing to gain by using UV islands and a lot to loose. We can always discuss how much work it is reasonable to put into a build but I do hope we all agree that spending a lot of time and effort reducing the quality is a bad idea.

[ChinRey]

Lesson ∞: Here we go again

With special thanks to everybody for being polite enough not to point out the obvious flaws in those seven lessons, here's the final(?) result:



1.4 and 0.7 are both rounded off to 1 LI of course so this final optimisation stage doesn't make much difference in itself. But as I said, it's all about getting more for less. There should be room for a visible chain in the low model now. Or maybe I should add a few bolts? Just to prove that I have nothing against hexagons. There may even be room for both within the 1 LI limit.

[Pamela Galli]

Thank you for your lessons, Chin.  I notice that your pictures look like they are taken with shadows on -- not sure about Ambient Occlusion -- which gives a nice 3D effect without baked AO.

I normally build for those who have those options turned either off OR on, since they can really slow some computers down -- or people just don't know they can be turned on. (I keep them off except for pictures, since my super powerful iMac only performs at a mid level in SL :matte-motes-crying:) That means adding shading to pretty much every texture I use, whether baked or Gimped, mostly using UV islands tho sometimes not. Very tedious (yet strangely rewarding). I am not sure what you mean about using symmetrical UVs instead of islands. What is the difference?

[ChinRey]

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Pamela Galli wrote:

Thank you for your lessons, Chin.

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Yw.

Ummm... is it stupid of me to give away trade secret this way?

 

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Pamela Galli wrote:

I notice that your pictures look like they are taken with shadows on -- not sure about Ambient Occlusion -- which gives a nice 3D effect without baked AO.

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The pictures of the current prim sign were taken with graphics set to ultra. For the metal parts I used the same texture both as diffuse and specular map (another lag saving technique btw although it doesn't lower any of the officially calculated weights). The wood and the sign are just good old textures. The wood texture is so rich to begin it that any additions would be overkill and only result in that silly plastic/doll house effect you often see when people get overexcited about all those new wonderful surface effects. The shading and smudge on the sign are all added manually in paint.net. Generally I prefer to combine Overlay and Color Burn to get a richer shading than what Color Burn alone can do.

All the pictures of the mesh sign were quick-and-dirty work-in-progress pics, standard mid level graphics, quick texturing with no additional surface maps. I didn't even bother to set a specific windlight - this was all about meshes, not textures after all.

 

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Pamela Galli wrote:

I am not sure what you mean about using symmetrical UVs instead of islands. What is the difference?

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Here's the UV map of the lowest LoD model from Lesson 6, all materials on top of each other:



The result of an UV map that wasn't ideal to start with and then had most of the vertices removed.

The UV map of the final lowest LoD model looks like this:



That change alone reduced the LI by 0.4. Similar changes to the other model also reduced the LI although not nearly as much as that. The rest of the final LI reduction came from more efficient chain links and removal of some other superfluous tris in the mid model and straightening up the low LoD model.

Oh and a new secret trick I learned from Drongle although he doesn't seem to be aware of it himself. You don't expect me to give away all my tricks do you? That would take too long, would spoil much of the fun and besides, as the owner of a well known builder school once told me, you can teach people how to fish but you don't necessarily show them the best fishing spots. He told me that after I had stumbled across his best fishing spot myself so maybe I can give you a little challenge there: what is that new secret trick? (Hint: read Drongle's recent posts here and take them out of context.) Or don't bother. It's just a minor LI reduction anyway.

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Pamela Galli wrote:

That means adding shading to pretty much every texture I use, whether baked or Gimped, mostly using UV islands tho sometimes not.

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There's no limit to how much details we want to add to our builds, is it? I've been trying to figure out how to add welding seams to that sign.

One occupational hazard all builders and everybody else who do creative work has to deal with is the tendency to get too hung up on details. We see every little thing, especially and annoyingly every little flaw. Other people don't usually see it that way, they see it as a whole. Ideally (although far to rarely) in SL they see it as part of the whole.

More textures mean more lag of course and that is serious enough. But even apart from that, too many details can easily reduce the visual quality. Take a look at a typical Blueberry piece of clothing. Notice how simple the design is compared to so much other SL clothing? That simplicity doesn't make it look any worse. On the contrary, it looks much better that way because lack of distractions helps bring forth those few details that are crucial for the overall look.

[Pamela Galli]

Oh okay, so you mean putting all the UVs on one layer as opposed to stacking them? 

Everytime we share "This is how I do it." we potentially share our trade secrets ;-D But as you say we all have to draw a line somewhere as to how much time we want to spend on the detail work that makes our builds stand out, and our priorities will vary. And as for details, what I hear over and over from customers is appreciation for details. And you know what? I don't know what they mean. ( I should really ask "Like what?" but that seems rude.) Most of what I make is technically pretty simple, tho the simplest things do take me a very long time. 

 

 

[ChinRey]

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Pamela Galli wrote:

Oh okay, so you mean putting all the UVs on one layer as opposed to stacking them?

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I mean aligning them. In the final UV map every single vertice has the coordinates <0,0,>, <0,256>, <256,0> or <256,256>.

In other words, the whole list of UV coordinates only has two different numbers. Dowload weight depends on the mesh's file size after it has been compressed and the more identical data bits and bytes the file hold, the tighter it can be compressed. This is perhaps the biggest of all LI saving tricks.

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Pamela Galli wrote:

And as for details, what I hear over and over from customers is appreciation for details. And you know what? I don't know what they mean.

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Listen to this:

It's a single cello playing one single note at a time yet we hear full chords.

The part of the human brain that deals with sensory input is eminently good at filling in the gaps and we see, hear, taste, smell and feel far more details than what the sensory organs actually catches. That brings up another aspect btw. SL is supposed to be a world for fantasy. What happens when it gets so detailed there's no room left for the imagination to play in?

Of course, there is no textbook answer to how much and which details are needed to give the right experience. There are some guidelines but in the end it's pure art.

Edit: we're talking visuals here, not sound so maybe this is a better example than the Bach Prelude:



[Pamela Galli]

I think my customers are Norman Rockwell fans :-)

[Pamela Galli]

This is the house I am working on, with shadows and AO turned on, and with them off:

 



 

 

Not much difference!

[Chic Aeon]

While I work differently than you do, my aim is also to have pretty much the same look for those NOT with ALM and Shadows (of course shadow will do all sorts of things depending on the Windlight so let's say "simple shadows" ).

 

When I first looked at Chin's note about the mapping it was pretty confusing and then I remembered that those are (I believe) mapped for TILING TEXTURES which I seldom use any more. That method would not work for ME at all and not for you either if I am understanding things correctly. 

 

So ONCE AGAIN it is how we work and what our final model will be that determines how we map. Almost all of the UV maps that I have seen on this forum are islands. I can think of MANY reasons why that is good for me -- especially with Cycles. When you are making mesh to take tiling textures, that is a WHOLE different thing.

 

So for any beginners that are getting confused --- well, there is a reason.  

 

I have no argument that this UV method lowers upload, but I don't see how it can work with cycles baked or even ambient maps baked with textures added via graphics software.

 

So we are talking APPLES and ORANGES here and likely getting folks that haven't put in those thousands of hours even more confused.

 

 

This is my in progress texture for the roof areas. It is not the FINAL one as the ceiling is beyond boring for lighting and I need to play with that some.

But I wanted to put up an example of the complete bake so that hopefully those reading this thread and blinking mightily might have a better idea. You can see that one section is for the roof (one material) and another for the ceiling (one material) and some for metal trim, and exterior wood and lighter wood (it is a Victorian after all and they were very into many colors and textures). 

 



 

I will say that learning how to map for tiling textures is a great place to start for those learning mesh. I doubt though that it is the end goal for most folks .   

 

And yes, someone buying this COULD put tiling textures on if they would like, adjusting the repeats and placement. I amost always map with that in mind now.  They will of course lose all those subtle nuances that I spend time adding LOL, but that's OK if that's what they want. 

 

 

 

[Pamela Galli]

That's impressive cycles work, Chic! 

[Chic Aeon]

Thank you. Only took a year and a half  -- well maybe not quite but close .   And I keep learning things by accident now that I don't have to concentrate so much on the "basics". Ah that basics list is a long one. 

[ChinRey]

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Chic Aeon wrote:

 

I will say that learning how to map for tiling textures is a great place to start for those learning mesh. I doubt though that it is the end goal for most folks

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Why not?

Don't get me wrong, as I've said several times in this thread, the good old style texture mapping still has its place. But currently there seems to be a trend to believe that it's more "advanced" or more "professional" or more "modern" than tiling textures and nothing could be further from the truth.

As for cycles, well, it's easy and there's nothing wrong with doing it the easy way. But if you really want to get the lighting and shading right, take a look at the the Caravaggio painting in my previous post. That photo doesn't really do the original justice of course but you should still be able to see it. Can a computer program do that? I think not.

(The shading wasn't why I posted that image btw but it works for that too. Caravaggio is after all particularly famous for his light settings and why learn from studying the real masters? The point I wanted to the picture to make was that nobody was going to get the point unless they were told. I'm surprised if nobody knows the answer already though, the picture is used quite often to test people's visual perception and attention to details.)

 

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Chic Aeon wrote:

So we are talking APPLES and ORANGES here and likely getting folks that haven't put in those thousands of hours even more confused.

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Yes probably because it's a question of what the purpose of the model is. If it's supposed to be a standalone item, complete in itself you want to give attention to every little detail, just like those people who spend thousands of hours building cathedrals from Minecraft thingies (or from matches before it all became digital).

But if it's supposed to be a part of a bigger whole like a virtual reality environment, you have to think different and consider boring stuff like focal points, visual layers, context and resource management. That's when things start to get really tricky and suddenly the answers aren't nearly as clear anymore.

[Chic Aeon]

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ChinRey wrote:

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Chic Aeon wrote:

 

I will say that learning how to map for tiling textures is a great place to start for those learning mesh. I doubt though that it is the end goal for most folks

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Why not?

Don't get me wrong, as I've said several times in this thread, the good old style texture mapping still has its place. But currently there seems to be a trend to believe that it's more "advanced" or more "professional" or more "modern" than tiling textures and nothing could be further from the truth.

As for cycles, well, it's easy and there's nothing wrong with doing it the easy way. But if you

really

want to get the lighting and shading right, take a look at the the Caravaggio painting in my previous post. That photo doesn't really do the original justice of course but you should still be able to see it. Can a computer program do that? I think not.

(The shading wasn't why I posted that image btw but it works for that too. Caravaggio is after all particularly famous for his light settings and why learn from studying the real masters?

The point I wanted to the picture to make was that nobody was going to get the point unless they were told. I'm surprised if nobody knows the answer already though, the picture is used quite often to test people's visual perception and attention to details.)

 

 

I taught college level art for over 20 years. I do know who Caravaggio is. Not my favorite, but I do appreciate the school.

 

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Chic Aeon wrote:

So we are talking APPLES and ORANGES here and likely getting folks that haven't put in those thousands of hours even more confused.

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Yes probably because it's a question of what the purpose of the model is.

 

Exactly. And I am done with this thread

.

 

 

 

 

If it's supposed to be a standalone item, complete in itself you want to give attention to every little detail, just like those people who spend thousands of hours building cathedrals from Minecraft thingies (or from matches before it all became digital).

But if it's supposed to be a part of a bigger whole like a virtual reality environment, you have to think different and consider boring stuff like focal points, visual layers, context and resource management. That's when things start to get really tricky and suddenly the answers aren't nearly as clear anymore.

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[ChinRey]

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Chic Aeon wrote:

I do know who Caravaggio is. Not my favorite, but I do appreciate the school.

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Same here really. But his work is certainly worth studying for anybody who wants to learn about light and shadow effects and of course, the optical illusion in Supper at Emmaus has made it a classic textbook illustration of how we preceive our surroundings.

[Pamela Galli]

The reason  we can't make our second life creations light and dark like a Caravaggio , is because we have to make them for not just one environment but multiple ones, including ones wth dynamic lighting and shadows. So much of the baked lighting must be subtle, like on a cloudy day.

 It seems to me that using tiled textures in most cases would severelylimit ones use of light and dark.

[ChinRey]

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Pamela Galli wrote:

The reason  we can't make our second life creations light and dark like a Caravaggio , is because we have to make them for not just one environment but multiple ones, including ones wth dynamic lighting and shadows. So much of the baked lighting must be subtle, like on a cloudy day.

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For those who want to learn how to do effective shading in SL, I suggest studying Hattie Panacek's work. She's the Caravaggio of Second Life (but don't tell her I said that, she'd die of embarrasment). She's even more obsessed with lag than me and still uses baked textures nearly all the time. She gets away with it by keeping the resolution down and by reusing textures whenever possible.

(Disclaimer: Hattie Panacek s one of my best friends and bulider sparring partner and one of my alts is her main scripter so it is possible my evaluation of her qualities is a tiny weeny bit biased )

[Pamela Galli]

She does beautiful work -- but is not using tiled textures, and my question is how using tiled textures can result in such effects. 

[ChinRey]

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Pamela Galli wrote:

She does beautiful work -- but is not using tiled textures, and my question is how using tiled textures can result in such effects. 

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Oh, I misunderstood you then. It's easy: first you spend a small fortune on the MP buying textures from the biggest and most prestigious texture stores. Then you rummage through your old inventory, find all the garbage you picked up at Yadni's on your first day in SL and realize that a few of the textures there are far better.

It's all about selection. High quality, versatile textures are precious gems and every time I discover one is a moment of celebration. You can find them in the most unexpected places.

Apart from the edges of the signboard, all the shading you see are just default basic shaders created by the viewer. They are actually much better than their reputation if you only give them the right surfaces to fall on.

I do use just about every function in the texture tab for all they're worth and often in rather unconventional ways but if you're talking about the beta grid pictures of my sign, there's nothing fancy. Quick adjustment of texture repeats, heavily darkened metal, that's all.

You can use AO on tiled textures too btw. There are some limits of course, you can't do edge shading for a start. But in principle it's the same and many of those old textures have quite heavy shading even though they didn't call it AO back then.

If you have time, take a look at Oliva Oriolus' Vintage Village. I think half that place is covered with stock textures straight out of the library folder yet it's absolutely perfect. That Old wood texture in the library with that garish technicolorish orange tint, it's not even tileable really. At Vintage Village it does the job of dozens of baked textures and it does it quite well. Don't ask me how he managed that, I have absolutely no idea. I wouldn't be too surprised if he couldn't explain either.

And that's it, really. I can't explain it better because it's more intuition than logic.

(ChinRey stutters and shuffles her feet, trying to find an excuse to change the subject...)

Oh, do you want to see my latest house?

I thought it was time I entered the luxury house market so you finally got some serious competition, so here it is!

It's got windows and a door and everything! What more can you ask for?

Come to think of it, it is actually a better illustration of how I texture than the sign was...

• Exterior walls and fundament texture by Crazy Mole
• Roof texture by Moard Ling
• Doorstep: Tooter Claxton
• All plank surfaces: my own shaded texture based on a plain plank texture by Eric Linden
• All other wood parts use the same texture as the sign
• Door handle: same texture as the sign, used both as diffuse and specular map
• Windows: a scaled down version of a Linda Kellie texture, used as diffuse, specular and even normal map
• Door's balancing face: my own 4x4 pixel full alpha
• Wallpaper... umm, that's actually an HL2 texture. We are allwowed to use them, right? I've double and triple checked and I can't help noticing that even TRU still sells them. But maybe I should have quadruple checked. Oh, well, I can change it if necessary.

 

All these pictures were taken with ultra graphics, windlight set to standard 9 AM.

Here's how the house looks with medium graphics:

I don't know what other thinks about the looks of course but I'm quite happy with it. And it's all textures I've just stumbled across - hidden among huge piles of garbage I have to admit. Some I've edited

One of the advantages of doing it this way is:

3909 display weight. That's not going to lag down anybody's computer

Another advantage is of course that it only takes ten minutes or so to make this little collection:

[Pamela Galli]

Those do look good, even without shadows on, those are good texture selections :-) Also good job repurposing the mesh to create so many versions (that is what I do, too).

 

[ChinRey]

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Pamela Galli wrote:

Those do look good, even without shadows on, those are good texture selections :-)

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Thank you!

I realized after I posted that I cheated quite a lot, by accident, not on purpose. Only two of the textures on that cottage are truly tileable. One is seamless but with to obvious a pattern to work across large surfaces, three are only repeatable horizontally and two are not repeatable in any way. But they're all versatile and that's the real point.

I also forgot to mention the normals. Smooth and flat normals are great for sharpening and rounding off edges but they can also be extremely useful for controlling the effect of the basic shaders.

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Pamela Galli wrote:

Also good job repurposing the mesh to create so many versions (that is what I do, too).

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Yes. If the purpose is to get lag down, reusing assets is by far the most important thing.

[Drongle McMahon]

"reusing assets is by far the most important thing"

And that's surely the most important advantage of using reuseable textures, tileable or otherwise, instead of baked textures. They can be used on a whole set of different models, so that you don't have to download a new baked texture for each. I guess it depends on how an area is set up, only really working of there are a lot of things made by the same person.

[Pamela Galli]

 It will never happen but it would be great if mesh could be instanced like textures can – like a given mesh would only need to be  rendered once, no matter how many copies were rezzed. My nine Windows would only need to be rendered once. I assume this would be something monumentally difficult to achieve.

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Drongle McMahon wrote:

"reusing assets is by far the most important thing"

And that's surely the most important advantage of using reuseable textures, tileable or otherwise, instead of baked textures. They can be used on a whole set of different models, so that you don't have to download a new baked texture for each. I guess it depends on how an area is set up, only really working of there are a lot of things made by the same person.

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[ChinRey]

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Drongle McMahon wrote:

And that's surely the most important advantage of using reuseable textures, tileable or otherwise, instead of baked textures. They can be used on a whole set of different models, so that you don't have to download a new baked texture for each.

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Oh yes, except to be more precise, some tileable textures are easier to reuse than baked textures. You can reuse baked textures too - Hattie for example is an expert there - and not all tileable textures are reusable. What matters in the end is not the individual textures but the total number of texture pixels the poor graphics processor has to keep track of. I wonder how a typical SL scene compares to a typical modern computer game there. Has anybody ever checked?

[ChinRey]

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Pamela Galli wrote:

 It will never happen but it would be great if mesh could be instanced like textures can – like a given mesh would only need to be  rendered once, no matter how many copies were rezzed.

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As far as I know, even with full instancing every single instance of an asset will have to be rendered separately. But reused assets mean there is less data to transfer and process through every link in the chain and that helps a lot.

 

Btw, since it seems nobody is going to do their homework

Here are the answers:

The LI saving trick Drongle unknowingly taught me was to export without triangulating. The SL uploader is more efficient than Blender's exporter when it comes to splitting bigger polys into tris. It's a good feeling actually: if the uploader can do something right, there's hope for everybody.

As for Caravaggio's Supper at Emmaus, there are two features that trick the eye there. One is the fruitbowl. It seems to be on the table but it isn't, it's hanging off the edge towards the viewer, only held up by the suspension of disbelief. The trick has a purpose btw, along with St. Peter's outstretched hand it expands the picture outside the canvas, inviting the viewer to join the meal. (As Caravaggio did himself, that fourth person standing in the background is him.)

Interesting but I was using the picture to show how the brain fills in details and that' the second trick. Take a close look at the table, examine the table legs...

[Drongle McMahon]

"You can reuse baked textures too"

Yes indeed. In my experience, that is very good for high resolution detail with minimum texture area, but, the way I have ever used it, you have to be extremely accurate in the geometry to get the ao to match perfectly. Here's an example I did during the beta. Not sure I would find the time nowadays. It was a real pain getting the pillars arranged to match exactly. It also restrained the geometry a lot. The savings are not nearly as high as using only tiles though.





ETA: Damn. Why does the forum software degrade these images so badly? .... Replaced.

ETA: Note that this was all before Advanced Lighting.