High Poly count and Sketchup

not registered yet · 28 Dec 2007, 22:51

Hi!

I'm pretty new at Sketchup and I'm wondering how does it performs with high poly count scenes. I'm thinking about something around 7 million triangles. I work on XP64 on a Q6600 quad-core with 4GB of RAM and a 640MB video card. I don't know if Sketchup benefits from 64 bits systems, if it has a poly count limit or any other kind of limitation on that side.

Thanks a lot.

[Tella]

Jackson · 28 Dec 2007, 22:53

@tella said:

how does it performs with high poly count scenes.

 Not very well. Although SU runs on 64bit systems, it can't run on more than a single core, so a 64bit quad-core system will perform no better than an XP 32bit Pentium 4 system for example. In fact, it may perform worse if the speed of one of your cores is less than that of a single core system. When I went from a 2.3GHz P4 system to a Centrino Duo 1.83GHz system SU slowed down by about 25%, while progs which support multicores sped up by about 75% which is what one would expect. Having said that, 4Gb Ram and a 640Mb carg will improve performance a bit, especially regarding texturing. A model with 20,000 faces runs ok, but sluggish on my machine (see spec below). I can only guess that 7m faces would be impossible for SU to handle on any machine- in fact a file with just 1% of those polys is probably a no-go. I may be wrong though- maybe Craig D or one of our landscape designers can chip in.

Gaieus · 28 Dec 2007, 22:58

Note Jackson that I put together all http://www.sketchucation.com/forums/scf/viewtopic.php?f=82&t=46 this "Gothic Project" into one file at the end and I could still be navigating in it.

I've just checked one church of it; it had more than 26k faces in it (and the monastery part is not even there and I had about six of these structures plus the terrain plus the plants plus the "space filling" houses plus the town walls and gates etc.).

Sure it was not easy, I used dummy components, extensive layering and for sure I did not try to orbit with shaded textures and sunshine on in the whole model!

Yest sure 7m faces sound a little bit too much.

not registered yet · 28 Dec 2007, 22:59

Thanks Jackson,

I'm a bit dissapointed. 20000 faces is quite a low count (that's around 40000 triangles, or maybe a bit more if there are more complex faces). Some 3D trees are much above that number; how do you handle those situations? Using components as a external reference solve those problems?

[Tella]

not registered yet · 28 Dec 2007, 23:00

Thanks Gaieus,

That project gives a nice idea of what Sketchup can do and cannot. What system were you using when doing that project?, just to have a reference.

Cheers.

[Tella]

Jackson · 28 Dec 2007, 23:01

@tella said:

I'm a bit dissapointed. 20000 faces is quite a low count (that's around 40000 triangles, or maybe a bit more if there are more complex faces).

I'm guessing you're a landscape designer? 20,000 faces for an architectural model is pretty big- in my example it's a large house, fully furnished and about 10 3D trees in the garden. For landscapes I realise 20k is almost nothing- I use Vue6i a lot and one of my current scenes contains nearly 3 billion polys- several thousand trees. I never ever export landscape scenes from Vue to SU as even the smallest one would be completely unworkable in SU. I think any system would crash every time. If I have to work on a large landscape in SU I would only model the terrain (with as few polys as possible) and some of the trees around the site of the building I'm working on. I tend to use 3D trees for foregrounds and 2D face-me images of the same trees for mid to backgrounds. Beyond that, I export to Vue and add distant trees and forests there.

As Gaius suggests, you could try replacing trees with proxy components- just a single vertical line if you have a lots of them, but to be honest you're unlikely to be able to bring a 7m poly model into SU in the first place. You'd have to delete (or replace) all your trees, then bring it into SU. Putting them all on a hidden layer might help, but just switching it back on could cause your system to crash if there's a huge amount of geometry on it.

As far as I know it's a fundamental limitation of OpenGL, although it might also be how SU uses OpenGL. It is worth bearing in mind that unlike some programs SU is always rendering in real time- it's interface is pretty much WYSIWYG, so it can't handle as much geometry as other wireframe progs.

Bruce- I'm not too sure about that, I just go by Google's own info:

"Note: SketchUp isn't optimized for dual processors. While it will run on a 64-bit Windows XP machine, there won't be a performance increase."

That and the fact that when I switched from a single core 2.3GHz Intel P4 machine to a Centrino Duo 1.83GHz SU slowed down and one of the Google guys explained that was because SU only uses one core. Of course, the other core can handle other processes while I'm busy in SU (rendering in Vue or VRay for example) so overall performance is better.

kwistenbiebel · 28 Dec 2007, 23:02

I hope reworking the core to be 64 bit and multicore 'adapted' (not just 'compatible') is on the google team's task list.
And if it's not...I'll come over at Boulder and write it myself on top of their whiteboards :egrin:

together: "We want high poly...we want high poly....we..."

:100k:

juju · 28 Dec 2007, 23:03

@kwistenbiebel said:

I hope reworking the core to be 64 bit and multicore 'adapted' (not just 'compatible') is on the google team's task list.
And if it's not...I'll come over at Boulder and write it myself on top of their whiteboards :egrin:

together: "We want high poly...we want high poly....we..."

:100k:

Yeah, this has been at the top of a few peoples wish list for a while, getting SU to 64 bit computing. Rest assured kwistenbiebel, I feel exactly the way you do.