|
|
Complexity of models for Virtual Earth 3D
About Truespace Archives
These pages are a copy of the official truespace forums prior to their removal somewhere around 2011.
They are retained here for archive purposes only.
Complexity of models for Virtual Earth 3D // New Users
Post by jrboddie // Nov 5, 2008, 4:03pm
|
jrboddie
Total Posts: 91
|
I have been working on a model for VE3D. On an older computer (2 GHz Pentium, 1 GB RAM, nVidia 6200) with a medium speed internet connection one of my models would only render as a blue box even after waiting 30 minutes. On the same system, the recent contest winning model took several seconds to properly render and then the navigation was sluggish.
My newer system with a dual core, 9600 graphics card, high speed internet connection has no problem, however.
So, my question is: are there guidelines for model complexity (maximum MBytes, number of verticies) when VE3D is the target? Sure, I could reduce my project to a box with a detailed texture but that sort of defeats the purpose of using tS, no? |
Post by TomG // Nov 6, 2008, 4:19am
|
TomG
Total Posts: 3397
|
First, that I have seen VE "get stuck" and a refresh solves the problem, so be sure it wasn't just bad luck, or that the servers happened to be down at the time.
Sounds like your model loaded on one machine, and not on another? Assuming it isn't working yet on the slower machine, this would make it a hardware issue rather than a VE issue.
Naturally any 3D rendering system - from trueSpace, to a game, to Virtual Earth - can exceed the demands of certain pieces of hardware, and the limits you set on the complexity of the model will be determined by just what hardware you want to be able to run it, and what hardware you don't mind excluding.
How big was the model in tS (in terms of file size)? How large are the textures on HD? With too many large textures, and too large a file size for the geometry, it may just take too long to download on the slower internet connection.
Also, depending on those two factors and the memory of the graphics card, it might just be too much for that graphics card to handle. A 6200 is not a great card, so it would be possible to exceed what it can do much more easily than for the 9600.
If either of that is the case, then it could be your model is too compelx for slower internet machines, or for ones with older graphics cards. In which case it is up to you whether you are fine with that, as the detail is important and you don't mind older technology not being able to display it, or whether you want to simplify the mesh and textures to enable it to run on older hardware even at the cost of some of the detail.
Things to try - first, reduce texture sizes. e.g. don't use 512x512 but try 256x256 for the texture sizes, so make them smaller. Perhaps use less textures, or even simplify what is in the textures to reduce file size too.
If you need to simplify the geometry for the older hardware, you can do so without going all the way down to a box of course! You can remove some details, perhaps replacing them with textures. If you have a fully modeled doorway with handles and hinges, consider removing the handles and hinges and try again, then consider simplifying the doorway from fully modeled with all the panels on the door to a flat door, then consider simplifying again to a simple indentation with a texture map, then consider simplifying to just a texture map and no geometry at all. But you can do it in steps and stages, to find the balance between detail and performance.
Note that VE will have a limit on what it can do, just as trueSpace does, just as Crysis does, etc. It will be possible to try to do more than the viewing machine can handle (for all 3D software) and result in slowdown, etc. With any real-time 3D system, this trade off between detail and hardware required to run it is always an issue, and tracking poly counts and texture sizes is always required.
Hope this helps - be sure to let us know more about the model, a screen grab in tS, file size of the file in tS, file sizes and number of image files being used as textures, etc, would all be helpful in knowing what might be the cause, and where best a solution could be applied. Assuming that you don't retest and find it was just a bad time for the server originally :)
Thanks!
Tom |
Post by jrboddie // Nov 6, 2008, 4:46am
|
jrboddie
Total Posts: 91
|
Tom,
Thanks for the reply. I did more experiments and found something interesting. First, while on the old machine, I made increasingly complex test models and exported them to VE3D. The largest was on the order of 10000 verticies and 800 KB. I think this is larger than the model I had trouble with. (Unfortunately, I don't have the original model at this location.) There was no problem rendering this in VE3D.
Then I went back to the collection which had the problem model (created on another machine) and switched the share property from 'private' to 'shared'. Suddenly, the original model rendered! (I.e. went from blue box to a full image.) I changed the property back to private and it continued to render. So, I conclude there was some anomaly in the collection data or a VE3D bug.
Anyway, the problem does not seem to be related to model complextity.
Would you recommend some maximum complexity benchmarks for VE3D models? I certanly want my VE3D model to be viewable on as many machines as possible and will be doing some complexity reductions. It would be nice to have an idea of when to stop (without actually running it on a weaker machine.)
And finally, I wonder if it would be a good idea for this forum to have a category specifically to discuss VE3D models given their importance to tS.
Jim |
Post by TomG // Nov 6, 2008, 5:23am
|
TomG
Total Posts: 3397
|
Sounds like it was a server related item, in that case - it can happen, sometimes the server gets stuck in feeding the 3D data out to the viewing machine, I guess it is related to demand at the time.
I can't really recommend maximum limits, because it is so hardware dependent. Your GPU, how much memory your graphics card, how much Ram for your computer, your internet connection speed, will all play a part in what makes for acceptable results.
Usually anything will render, just that you will get a slow down. I was able to slow my 8800 GTS machine down with a collection containing 100 houses. That was quite a lot of houses!
Other factors such as number of textures, whether its separate models or one model, could all play a part, and it will be impossible to give any set guidelines, any more than I could give hard guidelines for what makes a good real-time trueSpace scene.
Best thing to do is still to find a machine with the minimum specs you are targeting, and ensure the project runs well on that. In general for real-time 3D though, always aiming for as small a texture size as you can with the least geometry you can get away with is a good general approach ;)
HTH!
Tom |
Post by jrboddie // Nov 6, 2008, 5:47am
|
jrboddie
Total Posts: 91
|
Thanks, Tom. I understand your point.
The VE Gallery contest has a judging criteria of:
"Good modeling that shows enough detail but without excessive polygon counts."
Just wondering what 'excessive' means in this context. Can one even measure the polygon count in a VE rendered object (outside of tS)?
What do you think has the biggest impact on VE performance, vertex count or filesize (probably largely due to textures)?
Perhaps with a forum category for VE, there would be more discussion and one would get a sense of what is normal, at least.
Jim |
Post by TomG // Nov 6, 2008, 6:35am
|
TomG
Total Posts: 3397
|
Again, biggest impact would depend on hardware. If you have a graphics card with 128Mb then texture sizes will be more of an issue than if you have 512Mb of memory. And you can have a faster GPU with less memory, or a slower GPU with more memory, which could tip the balance between whether textures or geometry were more of an issue.
"Excessive" is more of an artistic thing than a science. Getting the most detail and best looks out of the lowest poly counts really is an artform in itself! Certainly loading down the model with so much detail that when we view it, it gives poor frame rate, then that would be excessive. I have two machines I view things on, a Quadro (slow, gives about the performance of a 7600 or even less), and an 8800 (one of the slower ones, with only 320Mb memory, but my main 3D machine).
People are welcome to post models they have on VE and give their poly count (you have to get the poly count from tS before export, VE doesnt give you those details), and then people can visit VE to view those and report their performance and their hardware. It will always be an estimated thing, as different hardware will give different results even when similar, so there will never be absolute rules that you can create for who can and can't view something at a reasonable rate. It still could provide some basic guideline information though, as long as you take it all with a pinch of salt :)
If posting such information, do be aware that you can have anti-aliasing in VE - it's not supported in VE itself, but you can override your graphics card to always provide a certain level of AA, and if you do that then VE will render anti-aliased in real-time, with an associated performance hit of course (how much of a hit depends on your hardware). Anyway, people should be sure to mention whether their GPU settings are forcing any anti-aliasing etc to ensure like is compared with like in terms of performance.
HTH!
Tom |
|
