Scalability

Marc · Post by **Marc** » Wed Feb 11, 2004 1:19 am

Hi !

I'ld like to know something about the scalability of Irrlicht. E.g. How many objects (like enemies) can there be while keeping a desireable framerate. Just about 10 oder maybe 100 or 1000? Has someone tried this yet? In most of the demos there is only one object...

Marc

saigumi · Post by **saigumi** » Wed Feb 11, 2004 3:31 am

Here is a simple test I did. My objects only have 10 tri's so this doesn't weight in on how long it would be with more complex models. So these performance numbers are mostly just affected by the screen graph.

I also had a sprinkling of gui elements loaded, as without them I've been able to get into the 1000 range of starting FPS.

-> Tue Feb 10 21:31:34 2004
: Objects:13 FPS:887
-> Tue Feb 10 21:31:56 2004
: Objects:73 FPS:584
-> Tue Feb 10 21:32:02 2004
: Objects:75 FPS:433
-> Tue Feb 10 21:32:34 2004
: Objects:168 FPS:276
-> Tue Feb 10 21:32:38 2004
: Objects:260 FPS:195
-> Tue Feb 10 21:32:52 2004
: Objects:553 FPS:100
-> Tue Feb 10 21:32:55 2004
: Objects:622 FPS:85
-> Tue Feb 10 21:32:57 2004
: Objects:662 FPS:79
-> Tue Feb 10 21:33:00 2004
: Objects:715 FPS:74
-> Tue Feb 10 21:33:08 2004
: Objects:791 FPS:66
-> Tue Feb 10 21:33:15 2004
: Objects:843 FPS:59

Marc · Post by **Marc** » Wed Feb 11, 2004 12:59 pm

I got a quite different result. I modified the Collision-Example by setting 100 feries in the scene. I only got 15fps on my nvidia Gforce4 Ti 4200, Athlon 2000+. The fps are independent of the rendering resolution; I got 15 at 640x480 and 1024x768. Perhaps the ferrie has too many triangles, I don't know, but it doesn't look that detailed. But 843 Objects with 59fps. Can you tell me your secret? Or can you send me this low-triangle model? (I don't know how to make models myself and I don't want to learn it anyway

Robomaniac · Post by **Robomaniac** » Wed Feb 11, 2004 2:48 pm

To get better FPS, you might want to recompile the engine w/ optimazation flags on, i went from 50 or so FPS in my one test, to 2000 (for about three runs) and then back down to 100 ish

Hope that helps, i'll also try to whip together a demo on my machine.

Marc · Post by **Marc** » Sat Feb 14, 2004 12:13 pm

Robomaniac wrote:To get better FPS, you might want to recompile the engine w/ optimazation flags on, i went from 50 or so FPS in my one test, to 2000 (for about three runs) and then back down to 100 ish

Hope that helps, i'll also try to whip together a demo on my machine.

So the dll in the 4.2 sdk is a debug compile?

Robomaniac · Post by **Robomaniac** » Sat Feb 14, 2004 12:22 pm

I havn't checked, but i recompiled the engine in dev c++, turned the project optimazation flags to best optimisation (sp) and recompiled. And whoops, i didn't get 2000 fps, i got 500, doing the same thing which i was getting 50 for, so a 10x increase. Just to let you know what i did.

SwiftCoder · Post by **SwiftCoder** » Sat Feb 14, 2004 7:10 pm

The collision demo probably isn't the best to be doing speed tests with, it has already been pointed out that collision detection with many objects is very slow.
Also, how many objects is not really as important as how many triangles are drawn every frame, if you have a Q3 .bsp level, most of your objects/characters should be culled, which will speed things up a lot.

Robomaniac · Post by **Robomaniac** » Sat Feb 14, 2004 7:54 pm

Oh, i forgot to mention, here are the results of my test

100 fairies, ~40000 triangles, 55 fps
200 fairies, 135125 triangles, 22 fps
300 fairies, 203342 triangles, 15 fps
400 fairies, 269295 triangles, 11 fps
600 fairies, 396725 triangles, 7 fps
1000 fairies, 662998 triangles, 6 fps
2000 fairies, 1316633 triangles, 2 fps

hope that helps

Marc · Post by **Marc** » Sun Feb 15, 2004 12:28 am

I got equal results to robomaniac. A few less frames, but the ratios are the same. But I wonder for the whole time, how do you get 2000 fps? This 2000 is probably not your framerate.

Robomaniac · Post by **Robomaniac** » Sun Feb 15, 2004 12:51 am

And whoops, i didn't get 2000 fps, i got 500, doing the same thing which i was getting 50 for, so a 10x increase. Just to let you know what i did.

Marc · Post by **Marc** » Sat Feb 28, 2004 4:32 pm

Today I had some time to play arounf with Irrlicht. And I still think there are some scalability probs, at least on my machine, for some reason.

Have a look at this

http://www.rhrk.uni-kl.de/~rochel/files ... cstest.zip

It opens a Window where you can specify a number of faeries that walk aroung randomly in the techdemo level and slide along the walls.
Here are my results:

10 faeries: 60fps
20 faeries: 33fps
50 faeries: 14fps

Why do u have so much higher framerates (with 1000 faeries). Please try it again with my implementation.

Robomaniac · Post by **Robomaniac** » Sat Feb 28, 2004 5:07 pm

i got pretty much the same results, is that using the straight compiled dll?

Marc · Post by **Marc** » Sat Feb 28, 2004 5:18 pm

I tried the original dll and I tried to recompile the dll. Same results. Can u send your example and src? I'ld like to see if it's really that much faster.

Besides, if Irrlicht can't handle 50 objects and the framerate sinks that much at 20 objects, it's completely useless for me. So I hope that I did something wrong, but if not ...

Marc · Post by **Marc** » Sat Feb 28, 2004 5:29 pm

Perhaps the Interpolation for the models is not optimized? Perhaps I should use this other model-type? But as I posted somewhere else in this forum, I don't know anything about model-making. So the only one I have is this faerie

Perhaps someone has a model in this other format and I can try if it's faster?
Or prehaps a statement on this from the developer?

Marc · Post by **Marc** » Sat Feb 28, 2004 6:25 pm

I tried it with a ms3d model. Same speed.