Limitations on Model complexity
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I managed to acquire a new Acer x2 dual core processor equipped desktop computer with 3 GB RAM on it. I was sure this would be enough to handle anything I threw at it, sketchup wise.
To my surprise, I was sketching up a simple torus and when I got to around 16 000 entities, it started lagging, a lot. I've only got a quarter of the torus done and I can barely copy the other 4 portions of it. I created very small polygons (180 rectangles per circle, with 360 circles) because I wanted a smooth surface, but I was sure my set up could handle it. Just how powerful a computer does one need to handle high polygon count for simple geometric shapes!
Here's a screen-grab of the quarter I got done (un-smoothed so you can see the polygons).
http://i215.photobucket.com/albums/cc42/Edward_Wolf/Refference/Step05.png -
Hi, Phillipe:
See this topic with Sketchup Guide Tommy: http://forums.sketchucation.com/viewtopic.php?f=15&t=10750
Dual core is apparently not used by Sketchup application. However, a sprightly processor and a good graphics card with sufficient ram is necessary. Google actually does have both a minimum and a recommended system specification on one of its pages. -
@philippelemay said:
To my surprise, I was sketching up a simple torus and when I got to around 16 000 entities, it started lagging, a lot.
16000 copies of the torus?
What graphic card do you have?
Have you updated the drivers?
Have you ensured Hardware Acceleration is enabled in SketchUp?Do you have Shadows or Edge Style effects enabled?
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@mitcorb said:
Hi, Phillipe:
See this topic with Sketchup Guide Tommy: http://forums.sketchucation.com/viewtopic.php?f=15&t=10750
Dual core is apparently not used by Sketchup application. However, a sprightly processor and a good graphics card with sufficient ram is necessary. Google actually does have both a minimum and a recommended system specification on one of its pages.Ok I'll check...
2+ GHz processor. I have 2 cores running at 2.8 each, so that's check.
2+ GB RAM. I got 3, check.
500 MB of available hard-disk space. Over 200 GB, check.
3D class Video Card with 512+ MB of memory or higher. Please ensure that the video card driver supports OpenGL version 1.5 or higher and up to date. SketchUp's performance relies heavily the graphics card driver and it's ability to support OpenGL 1.5 or higher. Historically, people have seen problems with Intel based cards with SketchUp. We don't recommend using these graphics cards with SketchUp at this time.Ok... This might be my problem, I have no idea what graphics card I have. I don't think my comp even has a card per-say, I think it's a graphics chip welded onto the motherboard.
@thomthom said:
16000 copies of the torus?
What graphic card do you have?
Have you updated the drivers?
Have you ensured Hardware Acceleration is enabled in SketchUp?Do you have Shadows or Edge Style effects enabled?
LOL, god no, if I'd tried that I'm quite sure my computer would have burst into flames. 16000 polygons, for some reason Sketchup calls them entities. As I said I'm not quite sure what graphics card I have, I'll have to check that, I bought the computer 2 weeks ago, so I doubt the drivers are very out of date, but I'll check. And no, I've never heard of Hardware Acceleration, so I haven't enabled it yet.
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If you happen to use CCleaner, it will display the name and model of your graphics card in its user interface. If you want more info about what's in and on your computer without too much difficulty, use Belarc's free (for home use) system audit. There are other more powerful tools for this kind of stuff but you just need a little info.
EDIT: Even easier would be if you acquired the computer through a vendor, the invoice may show this information. -
If you're not sure what kind of card it has it's possible that it just has an integrated video card which can cause some issues. I had an old dell desktop that had lots of glitches when it came to sketchup until i bought a separate nvidia card to put in it.
BTW, I know it's sort of a separate issue, but your poly count on that torus is almost definitely a lot of overkill. If you're sticking within sketchup, it's definitely overkill, if you're exporting it to a renderer then you should still be able to get by with a LOT less polys and have it look perfectly smooth and round so long as your polys are smoothed in SU the renderer should smooth out the lighting so at that point, you just need enough divisions so that you can't see any sharp edges at the glancing angles.
-Brodie
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Yeah, what Brodie says.
The number of longitudinal divisions for a cylindrical form could be as few as 8 to 12, maybe less in some cases. Or as much as in the 20s.
This all has to do with how close up your rendering view will be to the model and comes with experience. -
@mitcorb said:
Yeah, what Brodie says.
The number of longitudinal divisions for a cylindrical form could be as few as 8 to 12, maybe less in some cases. Or as much as in the 20s.
This all has to do with how close up your rendering view will be to the model and comes with experience.Wait, what do you mean when you say longitudinal divisions? The segements in the circle come as a default 24, so do you mean the number of circles that will make up the torus? Because 8 seems like far too few...
Basically what bugs me is when I take a simple geometric shape (like a cylinder), and then try to make it into something useful (like a rocket ship). As soon as I zoom in to add a window or a sensor node or a hatch or anything, the edges of the polygons that make up the damn thing become glaringly obvious. Maybe these segmentations can be fixed by rendering, but honestly I've... never rendered. I've always worked through SketchUp.
But thank you, that's what I wanted to hear. Either, "Only 16000 and you're starting to lag, hooo boy, it must be your computer." Or "16000 man! Are you daft, no one should ever have that many polygons." Or... "entities", whatever. Point is, my model was excessively rich in polygons, so next time I'll try to dumb it down.
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I can see that reference to longitudinal was maybe not the best. Look at it this way: Say you make your cylinder first by making a circle with the circle tool. While you're making the circle you have the option to set the number of segments representing the circle. I think the default is 20, which you can alter after the fact and before you extrude the cylinder. Each vertex on the perimeter of the "circle" would be what I was calling the longitudinal on the extruded cylinder. As for the circle, Sketchup, in the interest of program simplicity, creates a polygon to represent the circle. As I said, it simplifies a lot of things, but creates difficulties in other ways. A great deal more can be said here than there is room or time, and there are plenty of posts and publications regarding this. A good investment would be the book by Bonnie Roskes on Sketchup done around Version 6, maybe late 5, if there is not a later edition.
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@philippelemay said:
@mitcorb said:
Yeah, what Brodie says.
The number of longitudinal divisions for a cylindrical form could be as few as 8 to 12, maybe less in some cases. Or as much as in the 20s.
This all has to do with how close up your rendering view will be to the model and comes with experience.Wait, what do you mean when you say longitudinal divisions? The segements in the circle come as a default 24, so do you mean the number of circles that will make up the torus? Because 8 seems like far too few...
Basically what bugs me is when I take a simple geometric shape (like a cylinder), and then try to make it into something useful (like a rocket ship). As soon as I zoom in to add a window or a sensor node or a hatch or anything, the edges of the polygons that make up the damn thing become glaringly obvious. Maybe these segmentations can be fixed by rendering, but honestly I've... never rendered. I've always worked through SketchUp.
But thank you, that's what I wanted to hear. Either, "Only 16000 and you're starting to lag, hooo boy, it must be your computer." Or "16000 man! Are you daft, no one should ever have that many polygons." Or... "entities", whatever. Point is, my model was excessively rich in polygons, so next time I'll try to dumb it down.
Yeah, I'd say the issue is more in the modeling. I'm not quite sure I understand what sort of polygon issues you're seeing even with the description. Maybe a screenshot would help. I will say that how sketchup handles circles can cause issues like those you're talking about. Most people don't adjust the default number of segments at all and 24 segments can certainly be noticeable at certain angles. However, I'd expect those issues to disappear long before you get to the levels you're talking about - particularly because SU's shading can be more forgiving than a renderers.
-Brodie
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I will sometimes use 48 sides to create a circle, which works out to a new face every 7.5 degrees -- at the default 24 sides you are getting a new face every 15 degrees which is probably the lower threshold for something of a decent size to appear smooth, even with smoothing (Gouraud shading).
I don't see much reason to ever go above 72 sides on a circle, and would only go that high if the smooth qualities of the cylinder/circle was a primary element of the model -- or the model was huge and was to be viewed close-up.
Best,
Jason. -
Something else to keep in mind -- the higher the amount of sides you have the lower you can have the smoothing angle set... the smoothing function does take some system resources for rendering so a lower smoothing angle will tax your system less.
It's easy to determine the needed smoothing angle -- just divide 360 by how many sides you have.
Best,
Jason. -
Make sure you have hardware accel on. If you want to know what is in the machine graphics card wise down load and run glview322. It is from realtech(?) and will do a complete audit and report what Open GL is installed. You can also run the speed test here http://forums.sketchucation.com/viewtopic.php?f=72&t=20076 and get some idea of your machine capability. Note : you can expand the test size by the number of balls you use. Here is what I did to get an idea of what limitations to worry about http://sites.google.com/site/sketchupsage/faster/computer#AGPspeed
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Yo, mac1:
Sure wish I had known about these links earlier. Seems a lot of discussion could be answered about this 64 bit question by simply providing the link.
Thanks for sharing, because the info in both links is presented with clarity.
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