Size of Symbols?

[Emma G]

I'm working on a project with colleagues (who are using Rhino) and I've had to import small elements from them like Balustrading and small balconies. My current VWX model file has now reached 1.32GB (I have 15 sheet files in it) but my question is, how can I find out which of these imported elements is the largest and causing the file to be so so slow? I'd like to remodel the elements that are clogging up the file but am unable to determine which specific ones could be the problem.

 

Also, would it be better to split the file so the model is in one and the sheet files in another? Could 15 sheets files cause it to be the 1.32GB? Any advice greatly appreciated, i'm a bit of a novice..!

[Jesse Cogswell]

Usually the number of sheets has little to do with file size (though there is a setting that cause an exception to that).  Most of the time with Vectorworks, the file size can be affected by the following items (in no particular order):

• Texture resolution: Vectorworks doesn't do any kind of compression for images saved in a file.  I do my very best to keep my textures to around 300 KB or less.  It's really important to think of how the texture will appear in a Viewport.  If it's a small placard in the background that doesn't need to be super legible, then it probably doesn't need to be a full 4K texture.
• Complicated object history: Anytime you use Add Solid, Subtract Solid, Section Solid, or Intersect Solid, the solids making up the operation are all stored with file.  This can become huge if you are doing multiple operations to create an object (nested Solid Addition inside a Solid Addition inside a Solid Subtraction inside a Solid Addition).  This be easily happen if you use the Push/Pull Tool in the wrong mode, since it creates a level in the object history with each operation.  It's best to "clump" operations together, so if you have an object that wants four holes in it, it's best to create all four hole objects and subtract them in one  step rather than doing them one at a time.  You can remove an object's history by selecting it and running Modify -> Convert -> Convert to Generic Solid.  This will make the object "locked", so it's best to do near the end of the design process, but can really speed up your file.
• Undo History: I've noticed that your undo history may be saved in the file.  I've seen that "expensive" operations like importing PDF documents onto a design layer can balloon the file size, even if you delete the PDF.  But if you save and close the file, then open it and immediately save it, the file size will be smaller.  If I'm trying to reduce the file size on a drawing that I've been working on long enough to have a large number of undo actions, I'll often save and close, then open and save again.
• Referenced File Cache: If you have referenced files, such as using another drawing in a Design Layer Viewport, you have the option to Save referenced cache to disk.  This can be handy, it essentially saves the geometry from the other drawing into the active drawing, so if the reference is broken, you don't lose any content.  The downside is that if you are referencing a large file, then your working file will be even larger.  However, having the option unchecked also means that every time you open the file, it has to "update the reference" and load the drawing geometry into memory instead.  I once worked on a drawing where one of my referenced files was nearly 2 GB due to everything having 4K textures.  I save a new working file every day and auto-save up to 3 backups, so having the geometry in my working file would have taken up a huge amount of space, so I opted to not save the file cache.  But it took 20 minutes to open the drawing as a trade off.  Really ate up some time with how unstable Vectorworks can be.
• Saving Viewport Cache: This is the exception to what I said about sheets.  This option, found in Document Settings -> Document Preferences saves rendered and Section Viewports so you don't have to Update them every time you open a drawing.  If your drawing is mostly Top/Plan views and a few Section Viewports, having this option checked doesn't make an appreciable difference to the final file size.  But if you find yourself doing a lot of renderings on Sheet Layers with a high DPI, then the sheet layer count can really affect the file size.  I used to fight this a lot, photo-realistic renderings can take forever to render, so I would rather have the Viewport saved so I don't have to re-render them if I'm publishing a drawing set.  But your file is basically saving the final image of the viewport as an uncompressed image, which can make the file huge.  What I started doing instead is rendering my viewports out on a temporary sheet (not part of my published sheets), then using the File -> Export -> Export Image to export the final rendering as an individual JPEG file.  I then import that JPEG file as a referenced Image resource (not cached) and apply it as an image fill to a rectangle on the sheet layer.  This makes it really easy to update the viewport (just save over the referenced file), it is always ready to export the sheet, and it takes up practically no space in the drawing file.
• Grouping items rather than making Symbols: This is something that I run into fairly regularly.  It is easier to group items than to make a Symbol, so designers sometimes do that.  But if you group a collection of objects, Vectorworks is still tracking each of those objects individually.  So you if make an group of 10 objects and copy and paste that group 10 times in the drawing, VW is tracking 100 individual objects.  But when you create a symbol instead, VW only has to track the original 10 objects against the Symbol Insertion Point and then the location of each Symbol instance in the drawing against the origin.  IE, 20 objects in this example.  Now imagine you have groups consisting of 100s of objects.  It can make a huge difference.
• Mesh Objects: This is likely what you are running into when working with files imported from Rhino.  Complicated mesh geometry can wreak havoc on file size and performance, and unfortunately there's not a great way fix it.  If the objects are relatively simple, you can recreate them using standard VW tools.  But while you can run Modify -> Simplify Mesh to try to reduce the complexity of the mesh, you can quickly run into major degradation.

One thing you might try in your case is putting the imported Rhino geometry into it's own Vectorworks file and referencing it in as a Design Layer Viewport without caching.  This way it won't be added to your file directly, but might take a while to open.  Anecdotally I've had improved stability with this method as well, but running tests on CPU and memory performance didn't show any major difference between referencing geometry and having it native in the drawing, so it may not help much on the performance front.

 

I do have a plug-in that will Delete Object History across the entire VW file, which can be a shotgun approach of determining what is causing a large file size, but it won't tell you specifically which objects are large.  I could feasibly write up a script that searches the drawing for objects with history and count the number of layers to determine the heaviest objects, that might take me a bit of time.

[E|FA]

@Jesse Cogswell This is the best post on VW & memory/performance on the forum.  It should be required reading. Thanks.

[Emma G]

Thank you @Jesse Cogswell this is an incredible reply! I will work through everything that you have suggested and hope this fixes it. So just to check though, there isnt a setting in the Object info palette that gives the symbol size once its selected? It seems like a small thing but it would really help.. Thank you for taking the time to reply to my initial question! 

[Flair-Studio]

A thread with a wishlist from not too long ago, for the Resource Manager being able to display the size of the symbols...

Not sure if feasible but it would be a great achievement because at the moment it is difficult to have to guess which symbols needs reworking and not. It would be like turning the lights on...

 

[EAlexander]

Great advice from Jesse. Also don't forget to run the Purge command. Things in the resource browser, but not in the layers still contribute to file size. Also just good housekeeping. 

[grant_PD]

I used to copy out the symbol to a completely blank file, save it, and see how big the symbol was.  Tedious if you have a lot of symbols....

[Jesse Cogswell]

Okay, I took some time this weekend and wrote up a plug-in that I think will do the trick.  I call it Audit Symbols and it opens a dialog box listing all Symbol Definitions in the active drawing along with counts of all objects found in the 2D component, all objects in the 3D component, all objects with Modeling History, and how many times the Symbol appears in the drawing.  If you select a Symbol, it will display a list of all objects found within the Symbol, order by quantity.  If the Symbol contains objects with Modeling History, it will create a tree diagram of the full history.  It also shows a 2D and 3D preview of the Symbol so you know exactly which Symbol you are looking at.

 

From there, you can press the Edit 2D Component or Edit 3D Component buttons to jump straight to the edit container for the Symbol.

 

If you have a lot of Symbols in your drawing, this can take a little while to run.  I added a progress bar to let you know that something is happening.  Likewise, selecting an object with a lot of Modeling History will take a little while to sort out, shown in another progress bar.  There is a weird bug with VW2025 where the tree diagram won't fully expand when it's generated, only opening up one level.  Use the Expand All button to open it further or the Collapse All button if you want to narrow in a bit.

 

 

What you want to keep an eye out for is any Symbol with a high number in the # History column or really complicated Modeling History.  That stuff will wreak havoc on your file size.  Also, keep an eye out for Extrudes or Sweeps made with a large number of objects.  VW really prefers that an Extrude or Sweep contains only one object.  This tool will only show Extrudes and Sweeps at the end of the Modeling History, so it can't show all the problems, but it's a start.

 

The plug-in is attached to this post and has been added to my Manager plug-in linked in my signature.  A readme file can be found here with installation instructions if you would prefer to install the plug-in manually.

 

Please let me know if you have any questions or run into any trouble.

Audit Symbols.vsm

[grant_PD]

@Jesse Cogswell we are not worthy!

[Jesse Cogswell]

I was doing some testing on an old drawing that had especially "heavy" symbols (we're talking worst case scenario use of the Push/Pull Tool resulting in a symbol with 10022 objects in the 3D component, 3700 of them with some kind of object history) and caught a bug where some object types would not report themselves correctly, causing the plug-in to crash.  I also added another progress bar, this one with a Cancel button, that will pop up when you select a Symbol Definition.  Very helpful for canceling out when selecting an especially heavy Symbol like the example above.

 

Updated plug-in attached.

Audit Symbols.vsm

[Mark Aceto]

On 7/17/2025 at 5:32 AM, Emma G said:

I'm working on a project with colleagues (who are using Rhino) and I've had to import small elements from them like Balustrading and small balconies. My current VWX model file has now reached 1.32GB (I have 15 sheet files in it) but my question is, how can I find out which of these imported elements is the largest and causing the file to be so so slow? I'd like to remodel the elements that are clogging up the file but am unable to determine which specific ones could be the problem.

 

Also, would it be better to split the file so the model is in one and the sheet files in another? Could 15 sheets files cause it to be the 1.32GB? Any advice greatly appreciated, i'm a bit of a novice..!

 

unchecking "Save VGM graphics cache" has reduced file size by 60% for me

 

i've had similar 1.3gb files drop to 500mb after unchecking it (it really just depends though, so your mileage may vary)