"Paradise City" discussion board

Problem: SketchUp performs slowly when I place multiple buildings into my model, freezing for approximately 20 seconds.

I’m building a city with SketchUp. Its purpose is to act as a background for my comics, so there are no colors or materials: just a huge number of “hidden line” buildings. All the buildings are components, and groups of buildings are components themselves.

The model itself runs well enough :slight_smile: The problem is when I place these groups of buildings (I call them “clusters”) - that’s when SketchUp freezes for 20-24 seconds. It’s a huge problem for me, because that time builds up. I’m puzzled as to why the program slows down, since I have more than 3 GB free memory available while SketchUp is running, it only uses up to 20% of my processor and my GPU doesn’t seem to be the bottleneck either. Relatively speaking, the model isn’t even that large, it’s roughly 30 MB.

Is there any way I can speed up the process? And, if not, is there some other program I could use to continue building the city? I’ve already divided the city into 10 sections to make working faster, and I wouldn’t like to divide it further.

(I would have provided more pix but I can’t as a new user :confused:)

20% of a 5 core processor is one processor…

SU can only use one core for manipulating geometry… [like most cad applications]

if you have a dual core it will run at 50% + some overhead…

I’m guessing you have 7 cores and the 20% represents 1 core + overhead…


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Ah, cool. I know it’s a single-core program, but I didn’t make the connection. Looking into reference files now, maybe that could help. I already tried substituting ultra-low-poly models in place of my buildings, but that had no effect whatsoever.


It would be helpful if could could provide the model so we can interrogate it for possible improvements and techniques to speed up the performance. Possible?


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did you purge the model after each swop out…


John: I did, but the primary problem seems to be large size of the model itself. I could be wrong, though.

Chris: Okay, sure, here you go!

Are you using one of the “Fast Styles” ?

(Your forum profile does not say what SketchUp version you are using.)

Dan: a modified hidden line display mode (no profiles, no back edges, no extension, no endpoints, no jitter, color all same), no transparency, no sky, no ground.

SketchUp version is the newest one (16.1.1449 64-bit).

Generally, I do also experience delays when going in and out of groups when the model is large. I think you are already doing this, but working in small portions and later copy them into the “master” model later on.

is the delay significantly reduced in that divided model?

You are quite aware of your setup to keep the style as “Fast Styles” but, can we just double check on “shadows”?
And perhaps confirm that you see the (little green clock) next to your style, just we know for sure that your style is indeed “Fast Styles”?

Joseph: I checked out whether or not building placement is faster in the smaller region or full city. Actually, it seems - eerily enough - that the full model (which is 98 MB larger, more than 3x the size of the file I uploaded) works far faster. Maybe the difficulty is the fact that the buildings are so detailed? Perhaps I should try substituting all buildings for low-poly variants. I’ll try that out today, and let you know how it works out.

Shadows are off. Is there any other way they can be disabled? I mean does it matter if a component is marked as making and/or receiving shadows, if the shadows are off?
I checked for the little green clock, and my style indeed has it.

I made some experiments. Although I’m not 100% certain yet, I think I’ve found the answer I’ve been looking for.

Substituting ALL building components with boxes (that have no detail whatsoever) seems to do the trick. I’ve been experimenting with another part of the city,and so far performance for building placement is amazing. It’ll take me a few days to see whether or not I can keep the efficiency up, but it looks promising. I had assumed that detailed buildings would only be GPU-intensive and not processor-reliant when making several copies, but it appears I was completely wrong. With this new technique, I can quickly build the city up and then replace the proxy boxes with the actual components.

Live and learn, I suppose!

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If you have this, then it certainly confirms shadows and styles isn’t the issue here.

Check out Ghostcomp by Fredo
I never really got to implement it into my workflow, but it is meant to help workflows like yours.

:+1: Always the best way :smiley:

In this scenario I’d consider replacing geometry for textures and using simple boxes if you can.

Your textures can even be black lines over white backgrounds, but at this distance and scale, they would work as good as geometry (if not better) to convey the feeling of complexity of a city.

Also, if you by any means will render this, geometry is limited to what amount of detail you can get in sketchup, while texturing allows you to edit everything in the renderer side with image editors or texture editors.

You can add a lot of details like normal/height maps, color or white, toon shading, lighting, ambient occlusion, reflection and transparency and those by themselves, even if you decide to have black and white, can give a lot of artistic freedom.

Joseph: I looked at Ghostcomp, it seems like it effectively has the exact same effect as my manual swapping technique. I’ll have to test it and see if it is as efficient, since it removes a step from the workflow!

JQL: What exactly do you mean by “geometry” in this instance? As in using simple boxes with detailed textures, and I could later render the image in another application?
So far, I haven’t minded the level of detail I can get with SketchUp, because it’s a comic book background, and I never intended it to have color (this work will have digitally hand-drawn characters and another person as a colorist).
I like the idea of having all those effects, but I think that would necessitate a huge amount of extra work. Mostly because I already have over 300 unique building models complete, but no textures whatsoever. Since the model works well enough (the FPS is good with the finished buildings in place), I don’t know if I need better performance. Still, it’s an option I’ll keep open in the future; some indoor locations could really benefit from rendering.

Okay, I changed my mind. You got me interested.

Even if I won’t implement “normal/height maps, color or white, toon shading, etc” with this model, all those possibilities you wrote about sound so good that I want to try them out. Can you tell me
a) are there good plugins for rendering in SketchUp
b) if not, are there good free programs that could be used in conjunction with SketchUp to render images with any of the effects you outlined
c) what is a good program for texture editing - is Photoshop sufficient? I’m highly skilled with Photoshop.


Yes Photoshop is sufficient, if you’re highly skilled in it, don’t waste your skills on too much geometric detail.

Later on you’ll be able to tackle texturing procedurally (when UV unwrapping will be available for sketchup… wich will be soon enough). For now, just send me an exported JPG image from an elevation of one of your buildings and I’ll show you a real example of what I’m talking about.

Now for your detailed questions:

a) The best I know of is Thea render, wich I use. Amazing integration with Sketchup, and terrific quality.
b) Blender is the mother of all free software for 3d modelling, rendering, 3d animation (all that and much more, toon shading included). Though it’s free, it’s also huge, and probably works better with a plugin for sketchup called blendup.
c) Photoshop is absolutelly enough, but once you get going you can’t stop, I’ve been using Allegorithmic Substance, mainly Designer (procedural texturing) and Painter (handpainting a model with realistic effects). For doing that you need to know about UV unwrapping a model though and Blender can do that to a Sketchup model if export it to another format like collada. Soon enough that unwrapping will be able to be achieved very very fast inside sketchup too:


If Photoshop is your beach, dedicate yourself to texturing your assets and sketchup will become more fun.

Send me that elevation or even a whole building block if you want.

SketchUp’s OpenGL rendering engine has issues with geometry far from the Origin.

Upon resting the Axes to their default position I find the nearest corner of the “city” is some 20 kilometers from the Origin.

The “city” itself is nearly 21 kilometers across while the entire model is about 99 kilometers across.

In addition to the city plan there’s a terrain mesh some 60 kilometers long!
Little wonder it performs poorly. The model is >33 million edges. Endeavor to clean it up and pare it down.

• Turn on hidden geometry and then delete every bit of unnecessary geometry from the model.
• Purge unused.
• Reset the Axes to their default position and then move the city to the Origin.

See this compendium of performance modeling techniques:
How do I make SketchUp run faster? — SketchUp Sage Site

Working with Large Models

Thanks everyone for their help. I’ve renamed this discussion because I don’t really have problems anymore: proxy substitutes fix the problem for me, at least so far. The model has always run well, the problem was merely the placement, but with proxies there isn’t really a problem anymore.

Geo: You’re not wrong. The reason why it looks so idiotic in that version is that 90% of the city has been deleted (and later on the terrain was indeed deleted, but not in that version). I had no knowledge of SketchUp when I began working on the city, and I’ve constantly used backups for that exact reason. I’ve been experimenting with the limits of the program, and so far it works. I’ll have a look at the excellent video you linked, the new techniques will likely be crucial. Frankly, I’m amazed how well SketchUp has accommodated the project.

JQL: I’m honestly not 100% sure what you mean by “an exported JPG image from an elevation of one of your buildings”, I mean what do you mean by “elevation” in this instance? Forgive me, English is not my first language.
I’ll customize a city block model for you later today, when I have the time, for now I soon need to leave for uni.
I’ll have a look at thea, blender, blendup, allegorithmic substance, designer and painter.
Though I have no need to make the city necessarily look any better (it is a background for a comic book after all), I’m extremely interested in creating higher-detail indoor locations with actual renders.

(It looks like Ghostcomp has become obsolete. I can’t get it to work, despite following all the instructions. Even with FredoLib 6.9 installed (and checked for updates), the plugin keeps complaining that there’s no FredoLib to support it. Maybe it doesn’t work in SketchUp 2016? I don’t know, I posted a message on Fredo’s SketchUcation topic.)

I was doing the installation wrong, my bad. Got a functional ghostcomp plugin now!

Forget about it, I’ve just noticed you’ve uploaded the model because of the post from Geo. Follow his lead because that’s where most of the problems might be.

I’ll take a look at a building of yours and share it back. In your line of work, working with textures will unveil a lot…