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New TerrainSceneNode

Posted: Tue Oct 26, 2004 3:02 am
by nutterx
Hi Guys

I noticed recently that someone has written a few tut's for using libmini with irrlicht.
Anyway what i was thinking of doing was creating a new GeoMipMapping terrain scene node for irrlicht.

So is everyone happy to use libmini? ..if so i won't bother even starting this.

one problem is i don't know DirectX and have no intentions of ever learning it, so the new geomipmap stuff will be OpenGL only

I am also considering adding maybe 2 or 3 new terrain scene nodes ...so users can have a choice of geomipmap and maybe just a generic brute force method for small terrain meshes. I am unsure about using Quadtree because libmini takes care of that and ROAM 2.0 looks good but is not quite finished yet.

So what is everyone's opinion on me doing this? ... do you think i should bother with it? ...if so, should i implement it into irrlicht source code or should it be an external lib?

Nothing is started yet, just playing around with ideas and seeing if there is actually any call for something like this for irrlicht.

Posted: Tue Oct 26, 2004 4:26 am
by brcolow
LibMINI seems good, but having something built inside of the source code rather than depending on an external library is always better. Make sure to check out www.irrlichtnx.mmdevel.de for information on how you could contribute the code and make sure it gets made part of the library. Sounds good to me, you got my vote.

Posted: Tue Oct 26, 2004 8:56 am
by zola
It's always good to have terrain renderers that are an internal part of irrlicht.

I think it will be hard to keep up with libMini speed ;) because its really damn fast. Where I could see potential for speed ups is if You'd do geomipmap using the GPU (I think the ogre terrain scenemanager does this)

Btw if you use the drawing primitives from irrlicht You don't have to bother with DX nor with OGL.

Go for it!

Tom

Posted: Tue Oct 26, 2004 12:03 pm
by nutterx
zola wrote:It's always good to have terrain renderers that are an internal part of irrlicht.

I think it will be hard to keep up with libMini speed ;) because its really damn fast. Where I could see potential for speed ups is if You'd do geomipmap using the GPU (I think the ogre terrain scenemanager does this)

Btw if you use the drawing primitives from irrlicht You don't have to bother with DX nor with OGL.

Go for it!

Tom
yes good points :wink:

I haven't actually tried the irrlicht libmini demo yet ....what sort of frames rates are people getting with decent hardware like a 9800pro or something along those lines?? like with a decent size heightmap of 1024x1024 or larger? ....with normal OpenGL i am getting 350-400fps + with a 1024x1024 heightmap (with GeoMipMapping) ...but of course, no scenemanager, very very basic collision detection ....Vid Cards without no GL_ARB_vertex_buffer_object support really struggle too

Posted: Tue Oct 26, 2004 2:13 pm
by Guest
maybe u should look over at IrrlichtNX.....im sure they might consider ur help

Posted: Tue Oct 26, 2004 11:50 pm
by zola
It's very hard to give a resonable number. with libmini you have LOD which takes into account the actual form of the terrain plus you can give a resolution factor.

You can setup libmini to run fast with a very old machine if you lower the resolution, or you can give as much detail such that even my p4 3.0GHz machine drops frame rate to 4 fps.

best would be if you can compile the test app at your computer and do some tests with diferent terrains and terrain sizes.

with my setup (terrain 1025x1025, res 1000.0 point spacing 32, height scale 10) i get ~400 fps (P4 3GHz, GF FX5700 256Mb, release mode)

Posted: Wed Oct 27, 2004 1:37 am
by nutterx
ok no problems ...well i will start playing around with it and see how it goes ...if i start getting good results i will go over to irrlichtnx and see about getting it added, i won't waste there time yet until i have something to show em ...for the normal irrlicht i will just have to offer a download with the changes. I will report back in here once something is working. Regardless of whether this makes it into irrlicht or irrlichtnx i need the new terrainscenenode for my own personal use anyway :wink: ..linmini does look like it is working well but i would prefer to not have any more external libs

Cheers

Posted: Wed Oct 27, 2004 10:31 am
by knightoflight
Hi,
in the project-section was a thread "new terrain scene node" and after some months it seemed to be dead and i asked if we want to do a new terrain engine together:
...
> yes the last lifesign was in June...
> If its dead, why dont we make it together (with the same licence
> like Irrlicht) ?
> First we would have to decide which algorithm:
> http://vterrain.org/LOD/Papers/index.html
> And we would need someone who hosts the project probably with a CVS.
> I would like to help
...
But noone answered. So i looked by myself and found libmini and got help from the author. And zola now tunes it.

Now you ask would it be better to do an Irrlicht-own-engine. Sure, but if noone wants to do and to help ...

btw: On his developement-page Niko writes, that hes working on an irrlicht-terrain-engine.

Posted: Wed Oct 27, 2004 2:58 pm
by bal
That development page isn't quite accurate. And I think niko has other priorities than the terrain engine...

Posted: Wed Oct 27, 2004 7:51 pm
by Electron
if it can be easily integrated with irrlicht, that is it is no different for the user than using any other part of irrlicht, I see no problem with integrating this libmini, integragting it would be much easier than someone writing their own terrain renderer, and much more likely to get done.

Posted: Fri Oct 29, 2004 8:00 am
by knightoflight
Hi Electron,

you wrote:
> I see no problem with integrating this libmini, integragting it would be
> much easier than someone writing their own terrain renderer, and much
> more likely to get done.
I see a problem. libmini owns a different licence from Stefan Roettger. Please read the licence.

Posted: Fri Oct 29, 2004 7:17 pm
by Electron
ok, i didn't realize there were license problems. Where can one get information about libmini anyway? (maybe someone posted a link, but i missed it)

Posted: Sat Oct 30, 2004 6:45 am
by nutterx

Posted: Sat Oct 30, 2004 8:00 pm
by brcolow
The liscense is one thing, but another is that for me a few others libMini doesn't intergrate with our projects! I would really love to see your terrain scene node. So please, give it a shot!

Posted: Mon Nov 01, 2004 2:00 am
by nutterx
just an update:

Since i am fairly new to irrlicht i have been looking around and checking how it all works internally, so for the first GeoMip terrain scene node it will have to be rendered using immediate mode with no VBO support :cry: ....trent polack has a half decent slightly modified version of geomipmapping in his book which is actually perfect for irrlicht in it's current state :D ..so i have allready started implementing that to work with irrlicht, as zola pointed out if you use irrlicht's drawing primitives there is no need to care about opengl or DX.

Right now i am busy moving house so i have limited time to work on it but i will having something for u to check out in the next couple of weeks.

I won't update this thread again ....once i have something to download i will start a new thread over in "Project Announcements". Also bare in mind this new scene node will not be as fast as libmini .....once we modify irrlicht to support VBO and change this GeoMip implemantation to suit, that's when we should start getting some really good results .....this terrain scene node will still be better than what irrlicht has now and it will be capable of handling heightmaps of say 1025x1025 and maybe larger. In immediate mode opengl i am getting 120-150fps with a 1025x1025 map (haha stolen from FarCry :D ) using a patch size of 17x17 with a 9200se so that i think is still workable, i also tried another heighmap that was 2049x2049 and get very similiar results. I do suspect the framte rate will drop once implemented into irrlicht though.