Opening a Model Destroys History


Hi, I just opened a model and it lost all of it’s history. I used Save Small as my save method to minimize space on the hard drive in case that has anything to do with it.

This is a major bummer, as I am very careful to preserve history so edits are easy. Here is a screen shot:

(Brian Gillespie) #2

I never can remember what is saved and what isn’t with Save Small - And it looks like our help file doesn’t give much detail either:

@dalelear, can you elaborate on history saves with SaveSmall? @margaret, can you please update the help?

(Margaret Becker) #3

When we have @dalelear’s information, I will update the file.

(Pascal Golay) #4

As I recall, and I am pretty sure I am not making this up, there was a change somewhere along the line in V5 where at least some History info was lost from older files. I do not know the details,

(Dale Lear) #5

Hello Eric,

In general, Rhino V5 SR5 does save history when doing a SaveSmall. I have verified this by having record history on, creating three lines, creating a loft surface from the three lines, saving that model in a file using SaveAs with Save Small checked, reading the saved file, and then successfully editing the loft surface by moving the input lines.

Is it possible for you to send us the exact file you were opening when you got this message. That may help us find the bug that caused you to loose history.


(Dale Lear) #6

@margaret and @brian,

I looked at the V5 trunk source code and ran the saving code in the debugger.

The only information that the “save small” option omits from the saved file are render and analysis meshes for surface and polysurface objects.

If any other information is saved in a .3dm file with an ordinary save and not saved when doing a “save small”, then that is a high priority bug we need to fix. In simple tests, I could not reproduce the problem Eric reported using V5 SR5.

(Pascal Golay) #7

@dalelear, I don’t know if this YouTrack item has any bearing on this…



@dalelear, where would you like me to send the file. It says I can only attach image files on the forum.

Edit: Sent to

(Dale Lear) #9

The ID for this bug is “RH-20148” and the file Eric sent to is attached to the bug report.