FPs confusion

Okay. I'll admit it. .I am totally confused.

I am looking at the Alt 1 results right now... standing in the Welcome area. As you know, there is a Ahern/Morris sim crossing line there, a border if you will.

Now, the confusion is that I step into the Morris area/side and the sim fps reads 1500-2200 fps. Excellent I think. I note that the Basic FPS, which is, I guess, whatI am supposedly seeing on my computer(?) is about 5.7.

Looking the exact same direction, I step forward into Ahern. And check the same numbers...sim fps - about 1400... but suddenly my Basic fps drops to something below 3.2!

I am not talking a huge difference here in terms of what is (or should be) in my field of view.. just two steps!

The impetus for this little observational experiment on my part was two fold. A day or two ago, Haney was in the same area and invited people to stand in Morris if they were lagging horribly in Aheran's side of the Welcome Area. Secondly, today, afer teleporting, I had huge lag/trouble controlling my flight/walk from the telepads to a spot to stand in the Welcome Area.

Can anyone explain this to me? Speak slowly now.. I am a geezer with some missing brain cells relating to - well, to lots of things.

It could be that something isn't as detailed on one side of that border as on the other.

That said, I think you're more confused about what "FPS" means (And that's FPS, not FPs.)

The FPS in Basic is your FRAMERATE. It's how fast your computer is drawing what's going on on your screen. It's your frames per second. To get a great idea of how widely it can vary, go to the NE corner of Seacliff and stare out into the simless ocean. Look at the number. Then turn around and look at Seacliff. See how much it drops? Yeah.

The thing in the Simulator section, the SimFPS, has NOTHING to do with your framerate. Nothing at all. I don't even know what FPS stands for in this instance. It's an indicator of how 'fast' the simulator itself is running. Nothing to do with your framerate.

Bump.... as I don't see any useful/informative responses....yet.

Information to your client, even stuff you can't see, can cause the (overgeneralized) phenomenon of "lag".

Look at object updates to your client. In one sim it may be lower; its likely independent of sim FPS.

Client-side FPS (under Basic) refers to the number of frames per second your computer draws. So if it says "5 fps", that means that there are 5 pictures being drawn every second. Depending on where you live, television is either 25 or 30 fps, so you don't need many to give an illusion of movement; indeed, most cartoons rely on approximately 15-20.

FPS is affected by the number of polygons drawn in each frame, as well as the number of textures that must be used. Concequently, a large number of avatars in one area will result in the greatest slowdown. Alpha (transparent) textures are especially complex to render.

Sim FPS refers to the performance of the the server running the sim. The sim doesn't draw pictures -- what your computer interprets as a 3d world exists only as numbers on the server.

Sims can be slowed down by heavy physics usage, by being full of avatars, (see "Agents" and "Child Agents" in the Sim section -- these numbers are the number of avatars within the sim and the number of avatars outside but that can see in.) or by heavy script usage.

The two numbers are also unrelated -- the sim can be performing very smoothly, but your client's rendering speed is very low. This is because each number measures something completely different.

In a crowded area like Ahern, the reason your FPS is dropping is because just enough objects have come into view to add that much more data to your rendering view. (See the information under the "Advanced" tab of the Alt-1 display.)

As for lag in navigating, that can be something else entirely. Either it's because there's high network latency between your computer and the sim, (this was what was originally called "lag" or because the sim itself is having problems. You can check your ping time in Alt-1, Basic. Pings under 100ms are the most desirable.

Okay.. with that explanation in the bag.. and my understanding only slightly above that of a darter snail now....

Let's go for real comprehension of my question and confusion.

I looked at exactly the same thing from a distance of two steps apart. Two steps. Count them. 1-2.

The first position of viewing was in Morris. The second in Ahern. I looked at exactly the same thing in/from both positions...at least according to my monitor. Obviously I didn't change my hardware in between those two steps. The ping response to my client and to the sim was the same during the few seconds it took to take the steps and note the differences in the readouts.

So, the question remains... at least for my dense brain... with a draw distance of 64 (the lowest setting possible) limiting the "unseen but possibly impacting the view/numbers" items, it still confuses the hell out of me how the Basic FPS (my local rendering of a particular view) would be affected so drastically... especially when the slightly more distant view was the more effective/faster render!

Like I said in the original post, I may be slow, but if you/anyone can explain it clearly, I'll certainly chew on the explanation until I pop one of the remaining braincells, a blood vessel or I actually have some sense of comprehension... Please give it another/different go.


edited for typos

Like I said earlier, the differences between those two steps could be larger than you can see. For example, people's avatars get more detailed the closer we get to them. Other objects come into view at the extreme edge of your set view distance. You may not be able to see them, but your client is (now) rendering them.

Moleculor is correct. Look at the difference in the number of textures (Alt-2 and Alt-1, Advanced, Texture) and triangles. ("Ktris drawn" frame/per sec in Alt-1 > Advanced)

See?

Sigh. Ok. I give.. It must be magic.

There was exactly 1 other avatar showing on the entire Minimap at the time - and that shows what, a 256m square view? So, at 64m draw distance, avatar rendering is/was not a factor.

The two steps did not bring any additional structures into view based on later "measurements" from the same locations... no additional trees either. Going back to the exact spots and checking the numbers verified my feeling that that was the case then.

Like I said, I give. This makes zero sense...

A "quiet" time at a location, 1 person (2 if you count me) within draw distance view, standing in a no script zone (the entire welcome area has only the welcome sign and clock with scripts running AFAIK), no building going on within the draw distance, both SIMFPS's high, same ping rate.... and completely different results on my computer screen because I moved two freaking steps and crossed a sim border. Had I not noticed the orange property line or the change from Ahern to Morris, all I would have noticed was the performance change.

Absolutely eludes me. I'll chalk it up to PFM and relay that explanation to others if anyone ever asks me.

Thanks for taking a shot.

Make a cylinder. Turn it on it's side. Hollow it to 90. Look through the hole up close. Now back away.

See how it becomes a hexagon? That's the level of detail decreasing. It's not just avatars that have different levels of detail, it's a bunch of things, including the basic LL trees.

LOL i think someone wants an indepth coverage of FPS, not just a basic understanding?

Damn, billy.

You weren't supposed to tell anyone I can actually add 1 and 1 and come up with 2 99.99999999999999999% of the time.

Now my secret is out.

Doh

Someone is a bit sarcastic arent we?

Uh, billy.

My previous post was not directed towards you. I was making a joke.

I've been contacted by Korg stating that my explanations aren't detailed enough, so let me copy/paste an explanation on how graphics cards work and build from there.

I've removed large chunks of the explanation because Korg has already shown an understanding of how to access Alt-1.

-------

Everything in a 3D environment is made up of two dimensional surfaces. It's partly why looking at something from the inside of a non-hollow prim doesn't show the prim itself. The best way to illustrate this is by pretending everything in every 3D environment is made up of triangles.

A cube would be made of twelve triangles, two for each side.

With a sufficient number of triangles, you can create a reasonable approximation of any shape in existence. With enough triangles, you can make something that the human eye can't distinguish between, and the real thing.

If you take those triangles, and start connecting them at their points at different angles, keeping the triangle itself flat, but curving multiple triangles over an imagined surface, you can create the illusion of a three dimensional surface. Much like creating the side of a cube with just two triangles. The more complex the surface, the more triangles are required.

Now, modern day graphics cards have evolved beyond that. They have more than just mere triangles that they can render. They can cheat, and do outright squares, making a cube only six polygons instead of twelve. That's half (or close to it) the number or required operations to draw that polygon on your screen. More code includes things such as vertices and such.

But the plain and simple fact is, the more 'detail' in a 3d object, the more time it takes for your card to render it. This is represented as a number known as FPS, or frames per second.

The absolute best way to give you a concrete example of how this works is for you to go to a sim at the edge of the grid, or better yet an island sim, fly to the extreme edge, so you're staring out into the simless ocean, and then log out.

Then log back in and keep staring. Logging out and back in guarantees me that SL will stop rendering everything you just flew through that's now behind you. So keep staring out into the ocean. No prims in front of you. No avatars. Just some ocean, and maybe some clouds.

Then hit Alt+1. Check out the Basic section. See the large graph with a green line moving inside a red area? That's your graphics card's FPS.

Look at the number next to the word FPS. See it? It should be something higher than 10. Probably something more like 20 or 30ish. That's how many frames of graphics per second your graphics card is rendering. The only polygons it's really having to render is your one avatar, and maybe some water, and maybe a bit of the land and prims around you. Nothing much else.

Now, if you turn around and look at the sim, with all it's water, ground, prims, and avatars, you'll see your FPS drop like a rock. Hit Alt-Shift-9. You'll see all the prims vanish. Your FPS should go up. Now, find a bit of curved land that's in the distance, preferably some land that's got very jaggy looking peaks or something. Fly towards it. You should see the land 'reform' as you get closer. The reason this is happening is because SL is realizing you're getting closer to the land, and is adding more detail to it in the form of more polygons. It didn't need as many polygons to represent a similar shape when you were farther off because everything was smaller on your screen.

You can get the same effect with most curved prims, and avatars. The farther away you are, the less detail SL draws and the lower number of polygons are used in drawing the object. The closer you get, the more detail is drawn, which means more polygons and slower framerates.

So a single two step movement alters the shape of a large chunk of land, a couple dozen or hundred prims, and any avatars that are visible, which is why your framerate changes.

mole.. i still dont think its good enough.. could you please explain how to use the ALT-1 feature? Just kidding.. wow you people are good sports with all this madness.. i commend you!

I didn't contact Mole saying his posts are not detailed enough... He mangled a PM. That's all I will say about it.. It was a PM... should have stayed private. Even referencing it here borders on TOS violation.