Skip to main content

Impact of model scaling on rendering performance?

8 replies [Last post]
nnjones
Offline
Joined: 2006-09-26

I created a new world floor in Sketchup. After dragging it in world, it looked small so I made the scale 2.0. Does this:

(a) cause more data to be sent over the network?
(b) impact client rendering?
(c) cause any difference in performance?
(d) reduce the amount of information that the client has to process because it doesn't have to render as much of the environment? (based on the fact that you aren't seeing as much of the floor -- but seeing it more closely)

Even if you don't know definitively, can someone take a crack at answering this? Or has anyone experimented with this?

Thanks!!!

Reply viewing options

Select your preferred way to display the comments and click "Save settings" to activate your changes.
shawnkendall
Offline
Joined: 2003-06-10

In theory, changing the scale a particular 3D object or graph of objects should have no affect on performance, if it is, in fact, only a matrix/transform scale effect.

However, some sub-systems (collision for example) may have to work SLIGHTLY hard to work through the scale matrix. In practice though, this does not show up in any significantly measurable way in terms of performance with the exception being in an animation system. Because of optimizations done in animations system, scaling can induce some performance cost.

In the case of PW this should not be the case.

nnjones
Offline
Joined: 2006-09-26

That makes sense. Thanks, Shawn! Also, nice "seeing" you today. :)
-Nina-

shawnkendall
Offline
Joined: 2003-06-10

Yes, it was a great experience. The since of presence is satisfying and addicting ;)

jagwire
Offline
Joined: 2008-06-21

nnjones,

I think the resolution of the texture and polygon count affect the rendering time more so than the scale of an object. Normally a texture resolution of less than 1024x1024 is better as it's not taking up as much memory as a larger texture. Do you know how many quads make up the floor plane? More quads will take more time to render.

I think scaling your floor plane should be fine and shouldn't effect performance as long as your texture's resolution isn't too large.

Best Regards,
jW

nnjones
Offline
Joined: 2006-09-26

How do I find that info out?

jagwire
Offline
Joined: 2008-06-21

nnjones,

Someone else who has more experience with Google Sketchup will have to comment on the topic of polygon count.

If you open the image [texture] in photoshop, gimp, etc... it should be fairly straight forward to find the resolution of the textures. In general you'll want a texture to be a square power or two such as 512x512, 256x256, 128x128, etc...

Hope this helps,
jW

nicoley
Offline
Joined: 2007-02-12

I have been doing a lot of experimenting with textures. Here are some sites that I've had luck finding texture files with favorable licensing terms:

http://www.sharecg.com/b/6/Textures
http://www.mayang.com/textures/
http://www.cgtextures.com/index.php

But, as jagwire says, you do need to be careful about file size. The trick is to use the smallest possible texture file that will look good in-world. Cropping the textures to those power of two dimensions also seems to help. So if you want a wood floor, for example, find a nice image from one of the sites above, but use an image editor to reduce the size of the file. One way to do this in Photoshop is to use the "Save for Web" menu item, select PNG-24 as the file type (this is recommended in the Google SketchUp documentation), and then set the "New Size" to some smaller percentage. You'll have to experiment a bit with this, because if you shrink it too much, it won't look good in world. But you would be surprised how much you can shrink the file and still have it look pretty good.

Hope that helps,
Nicole.

nnjones
Offline
Joined: 2006-09-26

Thanks very much, Nicole! I will take a look at the sites and do some testing.