The LOD

[Rick Nightingale]

To add, regarding the number of triangles in each LOD...

Sometimes, an object does not need a 'proper' Lowest, or even a Low, LOD. A building, for instance, is so big that it might be visible at Medium from across a sim (longer than most people's view distance, so it vanishes because of that anyway), at default LOD factor (by which I mean Firestorm's default of 2; where I design for). In that case, it can save a lot of land impact to have an imposter, or just a collapsed few triangles preferably such that they are not obtrusively visible - there's a trick using a lone vertex, sorted to the top of the list, that helps with that. Likewise a small object like jewellery that would be vanishingly small at the lowest LOD anyway, might as well vanish or just have the simplest shape that is the same visible size as the object but at minimal triangle count.

So, sometimes seeing just a few triangles in the Low/Lowest LOD compared to much higher ones in the higher LODs is OK. Far more often though, that would show that the maker has simply 'cheated' and allowed the item to vanish to be able to claim a lower LI than is reasonable, or is simply to lazy (or lacking skill) to make the lower models. Hence the problem of objects vanishing when they shouldn't. A perfect (bad) example is the table I bought, before making my own. That was the one with a ridiculously high triangle count for High LOD, duplicated for Medium, but then just a few triangles for Low and Lowest when that was still visible (or rather wasn't) in a normal sized room. That's a typical example of a mesh imported from a 3D model site, where the model is intended to render at extreme detail in a 3D program like Blender; it is not appropriate for SL where it needs to render in real time, along with everything else in the room.

Edited May 13 by Rick Nightingale

[Rowan Amore]

40 minutes ago, Rick Nightingale said:

Hair at 100,000+ is ridiculously over the top, but yes there is plenty like that, especially older hair. A few thousand is more like it. In

I buy A LOT of hair and 100K is pretty much on the lower end for women's hair today.

[Rick Nightingale]

Hah - yeah, I just took a look at some of my wife's... varies but there were more above 100,000 tris than below it. My own three most used are 25,000, 50,000 and 100,000 tris.

I just realised I was getting confused with that useless metric, 'complexity' with the 100,000 number on hair. Edit: that's what I get for posting when I've been on the brandy. [Rick Nightingale goes to refill his glass].

Edited May 13 by Rick Nightingale

[Perrie Juran]

The LOD settings in the viewer are a range but from what I hear Firestorm Support say it is not necessarily a "more is better" setting.  The tech goes over my head but there is a law of reverse effort that can happen.  Someone who is smarter than me can probably explain it but when you set your LOD to 4 in the viewer some meshes collapse when you zoom in on them.  Firestorm Support recommends setting it no higher than 3.

I've been told Beq's article on LOD is very good.

http://beqsother.blogspot.com/2018/01/for-lods-sake-stop.html

[Mr Amore]

5 hours ago, Pixie Kobichenko said:

Can you tell me on FS where to find that setting?

In the Preferences, Graphics > Rendering tab

'Limit Framerate' is halfway down. It can be set as low as 15 FPS

I keep it at 30 which is enough for a game like SL

[AmeliaJ08]

53 minutes ago, Mr Amore said:

In the Preferences, Graphics > Rendering tab

'Limit Framerate' is halfway down. It can be set as low as 15 FPS

I keep it at 30 which is enough for a game like SL

Have they fixed the bug where the frame cap is half of what that slider says? I was experiencing that, like for 60fps cap I would have to set 120 in firestorm which was weird.

Anyway I just used the Nvidia control panel to set a frame rate cap instead.

[Perrie Juran]

18 minutes ago, AmeliaJ08 said:

Have they fixed the bug where the frame cap is half of what that slider says? I was experiencing that, like for 60fps cap I would have to set 120 in firestorm which was weird.

I thought that only happens if you have Vsync enabled.  From their Wiki:

"Enable VSync: Synchronizes the image frame rate of the viewer with your display refresh rate. Helps avoid screen tearing. NOTE: If your framerate is often below 60, this setting will drop your FPS down to 30; if your framerate is below 30 it will drop yours to 15, and so on. Therefore this setting is not advised unless you usually get over 60 FPS."

https://wiki.firestormviewer.org/preferences_graphics_tab?redirect=1

20 minutes ago, AmeliaJ08 said:

Anyway I just used the Nvidia control panel to set a frame rate cap instead.

I use the Nvidia control panel also.

[AmeliaJ08]

9 hours ago, Perrie Juran said:

I thought that only happens if you have Vsync enabled.  From their Wiki:

"Enable VSync: Synchronizes the image frame rate of the viewer with your display refresh rate. Helps avoid screen tearing. NOTE: If your framerate is often below 60, this setting will drop your FPS down to 30; if your framerate is below 30 it will drop yours to 15, and so on. Therefore this setting is not advised unless you usually get over 60 FPS."

https://wiki.firestormviewer.org/preferences_graphics_tab?redirect=1

I use the Nvidia control panel also.

Hmmm not as far as I remember, have had VSync disabled for a long time since I found it too to be quite broken hehe.

I'll investigate that one again, it might have been a quirk of my setup at the time.

[Thecla]

On 5/13/2024 at 12:55 AM, Pixie Kobichenko said:

This was helpful.  I've asked in the past how to know if something is stressing my poor computer out- & really wasn't given much advice.  This seems to be a good starting point to go around my home and pick up pieces that don't rezz properly on 1.5, especially standing right next to them.  Thank you

Actually, this is not going to help you out. In fact, if something does not rez properly at 1.5 it means that the creator attempted to reduce the LI of the object, but did it poorly. The object was likely very complex so they knocked the medium and low and perhaps even the high poly limits way down. The best measure for a lay person of an objects impact on your viewer/sim performance is simple LI, which combines multiple factors. In sum, if an object does not rez properly as you gain distance from it, it's just poorly made but may not impact your viewer performance. Also, from some of the most skilled creators in SL, I've seen high poly objects that hold up their LOD, rez quickly, and still have a very low LI. If you turn on wireframe you'll see an extremely efficient construction. So in that sense poly count is relative. Knowing if something has "too many polys" is not always easy to judge.

As for how a "lay" person can tell if a given product or object is either well made or "efficient" (not likely to impact performance), that can be difficult and sometimes impossible in advance of purchasing it, particularly if you can't inspect a rezzed copy.

I generally go my land impact. While triangle count is a better metric for viewer performance impact, land impact is a blended number that also incorporates how an object will impact the server, to a degree. My general rule of thumb is if something about the size of a steamer trunk or smaller is more than 1 LI, there needs to be a good reason for it; it needs to be extremely intricate, or be scripted. I will break that rule if I just really like something, but I try to hold to it out of principle.

If I can't inspect a rezzed copy, say with a product on the marketplace, the first thing I do is look at the LI. If it seems reasonable for it's size/form, then I'll be comfortable. If no LI is given, and there are no reviews it's buyer beware. Generally speaking, newer products will be better made, so when searching on the marketplace I will often sort by "newest first". If something is 100% mesh, that gives me a better comfort level than "partial mesh" as that indicates the product is old, or uses sculpts, or both. Yes it may use simple prims which is fine (looking at the product photo should give you a good sense of what's going on). Lastly, I avoid anything with sculpts entirely unless I can inspect it. There are OK sculpts and there are really laggy ones, and most of them out there are bad and there is no way to tell unless you can peek under the hood at the maps.

Edited May 17 by Thecla

[AmyPinkLegend]

I tried to upload a video but it wont allow anyhting over 4mb 🤬

Basically, If i change it from Default / Mid to High (Which fixes it) The second i close Edit Menu it reverts to default.

I can't get it to stick!

[Rick Nightingale]

14 minutes ago, AmyPinkLegend said:

I can't get it to stick!

That's the intended operation.

The selection in Edit mode is only to view it during that; it's only a (very useful) feature to help us design and inspect things. It has no impact once out of Edit or the item is deselected. It does not change any setting for the object, only tells the viewer to use a particular LOD while in Edit.

Only increased the viewer's LOD factor will do what you want and it cannot be done for a single object. Setting it above 2.5 is not recommended by the Firestorm people, although many, me included, set it to 4*. It's possible to set it even higher but I never would and that is really not recommended. It's not a case of straining your PC by setting it too high, rather that it can mess up the rendering altogether.

* Edit to add: only because of the number of rubbish items that don't work properly otherwise, and I tend to like a long view when on my land without noticing LOD models switching all the time. For my own made stuff, 2.5 would be fine even over the length of a region.

Edited Sunday at 10:50 PM by Rick Nightingale