Panning and zooming with very large files - Sketchup vs Blender

I am working a lot with large landscape files in Sketchup. With large I mean large as in some 800000 edges and 500000 faces. The size of the file discussed here is near 850 MB.
The problem I face is that panning and zooming in Sketchup is very slow under these circumstances, a fact I have - up to now - taken to be a direct consequence of size.

For the record, the file discussed contains a landscape divided into a large number of groups, this is very much intended.
Also, for the record, I use a GeForce GTX1080Ti graphic adapter.

In order to evaluate Blender 2.80 I exported the Sketchup file to .dae and imported this into the Blender environment. This experience with Blender vs Sketchup gave me several surprises:

Panning and zoooming in Sketchup for large files is a pain. Panning and zooming the same file in Blender is swift and instant, in fact, a pure delight. Please see the two videos attached.

Sketchup panning:

Blender panning:

The Sketchup file is some 839000 MB. The Blender file is only some 597000 MB.

Loading the file in Sketchup takes quite some seconds. Loading in Blender is MUCH, MUCH faster.

My simple question is: why is this so? Why is the Blender file much smaller?
And why on earth is zooming and panning in Blender so elegant compared to Sketchup’s behaviour???

Anyone to tell me what I am missing with Sketchup??

This is a design feature in SketchUp and normal behavior to help keep orbiting, zooming, and panning usable. When models get to be very complex like yours and the graphics card’s performance starts decrease, SketchUp first drops shadows, then it drops textures and finally in very complex models, it temporarily drops the complex geometry and shows the wireframe or even the boxes as your GIF shows.

Thanks for the reply, but I really did not understand this. Are you implying that panning and zooming in Blender is not “usable”??? It appears very “usable” to me…

1 Like

I didn’t say anything about Blender. I said that SKETCHUP is designed so that when your graphics card is struggling to display shadows, textures, and faces during camera changes it will stop displaying those things.

import the same .dae into SU and compare like to like…

john

Hmmm… may be that is a fair point.
Although, I would not have thought so, as I would believe that a .dae file imported into Sketchup would anyway be converted to its internal format, and thus behave very much the same.
But you are right, this should be tested.

However, importing the .dae file into Sketchup appears EXTREMELY much slower that importing into Blender.
In fact after working for - I believe - some 15 minutes the import of the .dae file just aborted
silently (Skethup not crashing).
So, the very same .dae file created by Sketchup could not be read by Sketchup. But Blender could!

Anyway, I will do some experimenting tomorrow, with a somewhat smaller test file, to try to understand more.

No, you did not.
But you stated some general design principles which I would believe would be exactly the same for Blender as well as Sketchup.
In which case, Sketchup has the possibility to be improved quite a bit. :wink:

1 Like

File size is a poor indicator of model performance.
Modeling technique has a tremendous effect upon model performance.
Moreover, one’s active Style settings greatly impact model performance.


Again, file size is a poor indicator of model performance.
An 850 MB SKP file is certainly over the top.
But 800,000 edges and 500,000 faces is nothing remarkable.

The statistics of this 894 MB SKP with 23.3 million edges and 13.8 million faces are remarkable.
Nonetheless, the model is easy to navigate, given one employs proper Style settings.

Over-Modeling_001


There are many highly experience modelers in this community.
Allowing them to work with and interrogate the model would yield meaningful information.
Posting a 5-second GIF, not so much. Share the file.

I am just very happy if someone can teach me how to use Sketchup’s abilities better, so here is the Sketchup file:


However, be informed that it is more than 800 MB large.

In a second test to import the generated .dae file using both Blender and Sketchup, I got this result:
Blender: approx 25 sec.
Sketchup: more than 30 minutes, Sketchup becoming unstable afterwards.

I also note that I reported the number of edges and faces wrong previously, the numbers are 10 times higher than stated above, please see figure below.

image

Going back to the original question, of why it’s smooth in Blender and not in SketchUp, from what I’ve seen in various tools, it’s the number of meshes (and redraws) that matter. If Blender is showing your scene as one mesh, that is a lot less demanding than the nearly 1000 meshes in SketchUp. But, I think there is a feature request in there somewhere. It ought to be possible to assign a layer, for example, to be handled as a single mesh. I’m in Los Angeles from tomorrow (for the Bootcamp Roadshow), I’ll check with the graphics engineers if that might be worth doing, when I’m back in the office on Thursday.

In the meantime, SketchUp is more for pre-visualizing things, and doesn’t have to have every nook and cranny, in the case of mountains. There is an extension called Skimp, that lets you optimize your geometry. That can leave you with something that is good enough visually, without being too demanding.

Here is a 139 MB version of your file:

https://www.dropbox.com/s/l951kjbc4z508z2/JNS_Terrain_Test-2skimp%20mid.zip?dl=0

I missed some tiles, but otherwise it gives the idea. You can zoom and pan around smoothly, even with SketchUp possibly creating 1000 meshes.

Upon opening the file, the active Style was Architectural Design Style which has Profiles enabled.
Profiles kill performance as do all the other eye candy Edge Style rendering effects.

The model performs exceptionally well after you turn Profiles off.
Test performance by typing this command into the Ruby Console … Test.time_display … hit Enter

Here, the model is running on an i7-6400K @ 4.00GHz | 16GB RAM | GTX 1060 6GB
For reference, testing an empty model on the system yields 60 to 61 frames/second.


2 Likes

Nothing at all. Blender is simply more efficient and optimized than SketchUp. My guess is that is just better code overall, top to bottom, when it comes to handling and displaying geometry. Right now Blender can handle real time rendering with their new engine. It’s insanely fast.

Be sure to look under the Options button when importing.
Tick … Merge Coplanar Faces to eliminate unnecessary geometry.

The results would be akin to these; achieved with ThomThom’s CleanUp³ - Merge Faces tool.

453,000 fewer Edges
273,000 fewer Faces

Merge%20Coplanar%20Faces


The reduction in geometry boosted performance a few f/s as well.
time_display_003_Merge%20Coplanar

In terms of model performance; the return on investing time in learning and practice quite often exceeds the ROI of fancy hardware.

For your interest, a compendium of performance modeling techniques.

1 Like

I agree with the two suggestions above:
-Mege Co-Planar faces when importing

  • Turn off Profile edges or any other styles
    And add the following:
  • Make sure the model is being imported with no Origin (base point location) as this can put it a long way from 0,0,0 and will make everything run very slowly.

I also wonder if SketchUp is attempting more complexity in:

  • lighting (sketchup sun vs whatever shader Blender uses?
  • SU has front and back faces (not sure what blender has)
  • Are the edges in blender ‘‘exploded’’ as SU edges usually are, or ‘‘welded’’ (into "‘polylines’’)?

how did you call up that little frame rate display Geo?

Ruby Console … Test.time_display …

or you can install the SU example ruby scripts and use a ‘Camera’ >> ‘Animations’ >> ‘Spin View’ menu item, and read FPS in the status bar…

john

First, thanks a LOT for taking the time to download and test my terrain file. Your experience and insight has helped me enormously. (I really did not expect anyone to take the time to do this. I was wrong! :slightly_smiling_face:)

While I - in general - do understand that style settings will have impact on render time, I would probably have had a hard time to realize that edge profiles ONLY could have such a major negative impact on this. In fact, I am still surprised by this.

My system is i7@2.67GHz | 12GB RAM | GTX1080Ti 11GB, i.e. somewhat less powerful than yours.
For the Sketchup file in question:
With edge profiles set I got a frame rate of 1.2375 rates per seconds.
Without edge profiles I got a frame of 58.3658 rates per seconds (actually a little bit higher than you reported, probably because of a faster graphic adapter).
This is an enormous difference!!! Is this really sensible?? Maybe someone at Trimble should have a look??

When I attempted to import the .dae file into Sketchup I was using Sketchup 19.0. The
importing did not work properly, as reported.
I have now updated to 19.2 (I never cared about 19.1), and the import is still VERY slow.
The busy wheel keeps spinning in nearly 30 minutes, and Sketchup appears to be unstable
afterwards (having some sort of hickups).
(BTW, I use the Merge Coplanar Faces option.)
So Blenders lightening speed import of 25 sec still leaves Sketchup pretty much in the dust.

I do apologize if I am slow here, but were you really able to import a generated .dae file from my Sketchup file back into Sketchup in a successful way? If so, how long did it take?

upload your .dae file and we can test that…

I imported your ‘full’ sized .skp in less than 30 min into a empty fast style SU session and although it was ‘mud’ once loaded, it’s to expected with only 245MB of ram on this mac…

on import I normally decimate .obj or .dae terrain files and can get around ok…

john

1 Like

Thanks a lot for your comments.
I am unsure how you can “import with no Origin”, I find no option for this when importing .dae. Please expand on this.