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Print at Jan 22, 2026, 5:05:23 AM

Posted by 2manyprojects at Feb 23, 2020, 7:09:51 PM

Launch multiple instances of SweetHome3D?
I searched around and could not find an answer.

Is there a way to launch multiple instances of SweetHome3D?

I am using the linux version and launching SweetHome3D-Java3D-1_5_2.

Attempts so far to launch multiple instances, even from different source locations just shows the one currently running instance.

Thanks,

M-

Posted by Puybaret at Feb 25, 2020, 7:07:31 AM

Re: Launch multiple instances of SweetHome3D?
It’s not possible without dirty tricks, but I could add an option for that in a future version. Why do you need that?
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Emmanuel Puybaret, Sweet Home 3D creator

Posted by rrraf at Mar 1, 2021, 1:26:38 AM

Re: Launch multiple instances of SweetHome3D?

It’s not possible without dirty tricks, but I could add an option for that in a future version. Why do you need that?

Hi,

I would also love that in order to be able to launch (night long) "multiple photo rendering" in multiple designs/files. Unless there's another way to achieve this?

Regards

Posted by Puybaret at Mar 3, 2021, 7:55:18 PM

Re: Launch multiple instances of SweetHome3D?
I added the com.eteks.sweethome3d.singleInstance system property in Sweet Home 3D 6.5 to make each launch of the application run in a separated process when set to false.

To use this property, add the line

-Dcom.eteks.sweethome3d.singleInstance=false

to a file named SweetHome3D.l4j.ini and stored in Sweet Home 3D installation folder.
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Emmanuel Puybaret, Sweet Home 3D creator

Posted by Mike53 at Mar 3, 2021, 11:07:11 PM

Re: Launch multiple instances of SweetHome3D?
Would that enable us to use 2 instances of sunflow too?

Posted by Puybaret at Mar 3, 2021, 11:11:06 PM

Re: Launch multiple instances of SweetHome3D?
Yes, but both instances will try to use all the cores of the CPU, so I’m not sure it will be efficient.
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Emmanuel Puybaret, Sweet Home 3D creator

Posted by The_Highlander at Jul 4, 2025, 3:12:42 AM

Re: Launch multiple instances of SweetHome3D?

I added the com.eteks.sweethome3d.singleInstance system property in Sweet Home 3D 6.5 to make each launch of the application run in a separated process when set to false.

To use this property, add the line

-Dcom.eteks.sweethome3d.singleInstance=false

to a file named SweetHome3D.l4j.ini and stored in Sweet Home 3D installation folder.

I too would like to be able to run two instances of your excellent program but I cannot find any file named: "SweetHome3D.l4j.ini" in the Sweet Home 3D installation folder (or anywhere else on my computer).

I am running version 7.5 of the program on a Windows 10 PC.

Does the facility only exist for Linux users or can you tell me how to do it in Windows 10 please?

Thank you, &
Kind Regards.
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There can be only one! 😊

Posted by Puybaret at Jul 4, 2025, 12:16:06 PM

Re: Launch multiple instances of SweetHome3D?
Just create the file SweetHome3D.l4j.ini in the same folder as SweetHome3D.exe
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Emmanuel Puybaret, Sweet Home 3D creator

Posted by The_Highlander at Jul 4, 2025, 10:21:41 PM

Re: Launch multiple instances of SweetHome3D?

Just create the file SweetHome3D.l4j.ini in the same folder as SweetHome3D.exe

Hoping that I had understood you correctly, I created a new text file (as shown below), renamed it as:"SweetHome3D.l4j.ini", opened it (with r/click > Edit ) and inserted the single line:-

"-Dcom.eteks.sweethome3d.singleInstance=false"

then saved it and moved it into the folder containing: "SweetHome3D.exe"

Having done that, I can, indeed, now open two instances of the program simultaneously!

Thank you so much for your help (and for your excellent program!). applause

Best Regards. biggrin

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There can be only one! 😊

Posted by Keet at Jul 5, 2025, 10:48:12 AM

Re: Launch multiple instances of SweetHome3D?
Be aware that with separate instances you won't see a newly imported furniture or texture library in one instance in the other instance until you restart it. With a single instance setup you would see an imported library immediately in all open projects. In your case I don't think that will be a problem but remember it when you have two instances running for normal editing and you import furniture or textures.

Also understand that photo rendering will not be faster by doing it in two instances at the same time instead of one after the other. The only advantage is that you can start them both and let them run through the night.
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Dodecagon.nl
1300+ 3D models, manuals, and projects

Posted by The_Highlander at Jul 7, 2025, 11:58:17 PM

Re: Launch multiple instances of SweetHome3D?

Be aware that with separate instances you won't see a newly imported furniture or texture library in one instance in the other instance until you restart it. With a single instance setup you would see an imported library immediately in all open projects. In your case I don't think that will be a problem but remember it when you have two instances running for normal editing and you import furniture or textures.

Also understand that photo rendering will not be faster by doing it in two instances at the same time instead of one after the other. The only advantage is that you can start them both and let them run through the night.

Thank you very much for your comments and cautionary advice which is most welcome. applause

You have also opened my eyes to something that I was not aware of (but, stupidly, did not bother to try out beforehand d oh

) that would have solved my problem entirely without the need for multiple instances! Doh!

Your comment:"With a single instance setup you would see an imported library immediately in all open projects." gave me pause to think: Hang on, does that mean that more than one project can be open at the same time in a single instance???"

Really that was all I was after in the first place! hugs

So I went back and opened a project, then using: "File > Open...", I opened another one and, lo and behold, both remained open at the same time (selectable from the Task Bar). I had just presumed (previously) that, if I opened a different project, it would replace the one currently open! Doh!

That's why I went searching on the web for ways to open multiple projects and came across the post at the start of this thread.

Thanks again, to all contributors; you learn something new every day, eh! blushing

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There can be only one! 😊

Posted by Keet at Jul 8, 2025, 8:39:27 AM

Re: Launch multiple instances of SweetHome3D?
I assumed you already knew about opening multiple projects with a default install. It's a classic multi-document interface.
I does NOT allow to start multiple photo renderings at the same time but that is not advisable anyway.
One quirk you will run into: when you have a dialog open in one project you can't switch to another project until you have closed that dialog. It's inheritant to a multi-document interface, not specifically Sweet Home 3D.
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Dodecagon.nl
1300+ 3D models, manuals, and projects

Posted by The_Highlander at Jul 8, 2025, 9:04:23 AM

Re: Launch multiple instances of SweetHome3D?
smile

I assumed you already knew about opening multiple projects with a default install. It's a classic multi-document interface.
I does NOT allow to start multiple photo renderings at the same time but that is not advisable anyway.
One quirk you will run into: when you have a dialog open in one project you can't switch to another project until you have closed that dialog. It's inheritant to a multi-document interface, not specifically Sweet Home 3D.

TYVM.

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There can be only one! 😊

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