Scenery object optimization for FSX

[spins_vmfa321]

Hello all!
I'm a recent user of your creations (in FSX). I have to tell you... the level of immersion I have received from your packages is just astounding. I cannot rave about it anymore, and I'm going to tell all my friends to check out your products!
Of course, many of the scenery were not designed with FSX in mind, which you guys have fairly warned us. Luke seems to have major issues with frame rates, but it's no more complex than JFK scenery in New York. What I was wondering, what could be done to the scenery to optimize it for use with FSX? More specifically, I'm willing to volunteer my services if I can to help convert some of the scenery over, with the creators permission of course, as it looks like a good way of learning scenery design (which I've become interested in after seeing many of your projects and what Blue Sky has been up to).
If it's a matter of converting textures to DXT5, and redoing tree textures, that seems to be fairly easy. If it's converting the BGL into 3DS max and re-exporting, I can do that also.

Any info you may provide is greatly appreciated!

Jamal

[rocket_26_]

Optimisation works for both Fs9 and FSX. It just happens that un-optimised sceneries perform better in 9 than X. The amount of work it would take to optimise exisiting sceneries is immense to be fair. The big problem is most sceneries use libraries, which means each object is a drawcall etc, by the time you have the whole scenery placed the drawcall count is huge and from my findings the biggest FPS killer in FS is drawcalls. It just so happens that FSX is extra sensitive with drawcalls and most users struggle to get good FPS before they add custom scenery.

[BadPvtDan]

There you have it from an expert scenery designer in both FS9 and FSX. Everyone has trouble with Luke and Nellis sceneries in either game...really, though...I don't think it is the sceneries as much as it is the 100 or so aircraft on the ground! Ha!

[rocket_26_]

Yes both Luke and Nellis both perform well to be fair in either sim on my system. IIt is indeed the AI which has the most impact, due to the sheer volume of aircraft. I can still get smooth FPS though.

[spins_vmfa321]

Ah ok, that's some good gouge! So, the best route for me is to edit down the number of aircraft I have spawned in there... as much as it'd pain me to do. It'd feel like splattering mustard on a Picasso...

[fishlips]

Or you could upgrade your PC!!!!!!!!!!!!!!!!!!!!!!!

[Firebird]

Ah ok, that's some good gouge! So, the best route for me is to edit down the number of aircraft I have spawned in there... as much as it'd pain me to do. It'd feel like splattering mustard on a Picasso...

Rather than editing, couldn't you just turn down the traffic percentage slider?

[MIKE JG]

Another option would be to edit the Aircraft.cfg entries so that each model only uses one texture for the whole fleet. Our packages stress reality so we provide a repaint (1024x1024) texture for every aircraft in the package. In some packages, that's over 100 aircraft and individual textures. More and more of our models have an additional prop texture or canopy texture on top of that. That can be several hundred textures that have to be loaded for any one "scene" in FS9/X.

Now having said that, each AI model still has to call a texture but logic would seem to say that if 100 models only have to call 1 shared texture, as opposed to 100 different textures, you might get better fps from that conversion.

As Ian has said, it really is the texture calls that slow things down. As he has also mentioned it seems that FSX is extra sensitive to texture calls (draw calls).

Have you ever noticed in game that the actual 3D models never seem to have an issue loading? They always seem to be there often times blank, without textures, while they wait for the graphics to catch up and add a texture to them. I see this all the time at Nellis. It's often very noticeable and the scenery seems to texture before the AI models. Then one by one, the AI models get their textures. Once all the textures are loaded, the fps rebound a bit.

So the number one way to optimize the fps in either platform is to actually get rid of the AI models. Each AI model at LOD1 probably has 3 to 4 times the number of polygons that a given scenery model will have. But that's not really what we're after as the AI are what really bring the experience to life (at least for me).

So the second way would be to try to optimize the speed of loading the AI textures by reducing the use of individual model textures to just one common texture for each variation. But then you lose the realism factor.

As scenery designers we can "cluster" our scenery sets into individual "scenes" that comprise multiple buildings that eventually get treated as just one object. If I combine 10 buildings into one scene, that uses just one texture sheet for the whole scene, that's a lot better than placing 10 separate scenery models that might use 5 different texture sheets. But to do that, requires a lot of planning ahead and a lot of tweaking to get the "scenes" placed just right.

So as a third party looking to "enhance" the already released scenery, there really is no way for anyone to do that after the fact unless they actually had the original model source files and literally rebuilt the scenery from scratch.

Another way as designers we can help is to reduce our use of individual scenery objects (cars, trucks, ground equipment) that are part of libraries. Each one of those individual objects requires a texture draw call and can add significantly to the slow down.

In the Nellis scenery, I tried to organize the objects into logical groups that the individual user could selectively remove to help their fps. For example, all of the ramp lights are placed as their own scenery bgl file so that if you wanted to remove them, you could without affecting the rest of the scenery. I believe I made the trees that way as well.

Using scenery object libraries is far more simple and quicker to use but results in lower overall fps. As with everything related to FS, it's all a trade off. If you make performance gains in one area, you seem to lose them in another.

I call it the Flight Simulator arms race......

[fishlips]

I agree with Mike.
Extra eye candy such as vehicles, ships, trains, trolly's, sign posts, fences, etc should have there own .bgl file so they can simply be removed from the scenery folder if the user so desires to have better frames rates or save on memory.
At the same time we as developers need to keep our eye candy at an acceptable level of polys and texture draw and I beleive we are now doing a good job at that now days. The use of LOD's and distance of sight tweaking is also important to apply to your models when possible. Obvously some models do require a high level of polys to construct a reasonable level of detail so those models need to be used in moderation within a scenery when close to the apron or runway areas.

Planning a head of time does save issues down the track but as most sceneries are built over many months not weeks, it is difficult to plan ahead when new information learn't over time comes to light. Catch 22 I'm afraid.

Generally speaking, as people update there PC's they will appreciate the extra eye candy in there sceneries.

Mark

[rocket_26_]

Any Fs9 model, aircraft or scenery will perform poorly in my opinion when used in FSX. Without a re export of the models using the FSX compiler you will not see your usual FPS figures.

I did some testing for this a few weeks back. My test scenery was a complex one, that being RAF Bentwaters which was designed for both sims.

I loaded up the FSX version in the FSX facing away from Woodbridge. REX on, sliders fully up, NO AI, I managed 38FPS average with the entire airfield in view. Now staying in the same position I went to the scenery library and changed the directory to our Fs9 version. Let it refresh and the FPS was 14FPS average.

Now consider this, all models, textures, etc etc are exactly the same. All built in GMAX. Only difference is that they were exported with each games compilers. So for performance in FSX, FSX code is needed for great FPS. It also explains why Fs9 coded AI perform poorly on my system despite me having a powerful machine.

[CelticWarrior]

Thanks for that, rocket. It certainly helps explain a lot. I wish I could get hold of the source files for all my FS9 AI and re-compile them for FSX