Mantaflow?

[BubbaBoBobSmith]

Thank-you so much for posting a fix for running Blender 3.x under Windows 7-64.

For others who are running Blender 3.1 in Windows 7, what happens for you when you do the following?

• Press F3
• Search for Quick Liquid
• Double click it from the list
• Press [Play]

In 2.92, I see an animated fluid simulation with particles.
In 3.1.0 I see the domain and emitter, but no particles.

Maybe I installed Blender incorrectly?
All I did was extract the file: "blender-3.1.0-windows-7.zip"

Then I double-clicked blender.exe and it ran.

• Modeling works fine.
• Rendering works fine.
• Load and save are good.

[nalexandru]

This is what happens when i follow your steps:

2022-03-21.02-10-55.mp4

It seems to be behaving as 2.92 on your machine. Can you try an older version that doesn't officially work on 7 such as 3.0 or 2.93 ?

[BubbaBoBobSmith]

I have 2.92 and 3.1.0 running side-by-side on a Windows 7 machine. The 2.92 Blender shows the particles flowing out. The 3.1.0 Blender doesn't show any particle flow. Both show the Domain and have the exact same Domain settings.

I've also tried it on multiple Windows 7-64 boxes with the same result. And I've also tried installing the 2022 Visual C++ update. Still no go.

[BubbaBoBobSmith]

Me again. I just tried the same portable .zip of Blender 3.1.0. from this site on a Windows 10 machine for comparison and the Mantaflow particles do show up okay on the Win 10 box.

So it seems like there's still something that Windows 10 has access to that Windows 7 doesn't.

[Loriem]

In 3.1.0 on Windows 7 I see this picture:

bandicam.2022-03-21.10-08-37-403.mp4

[BubbaBoBobSmith]

Ah. Okay. That's a good sign.

Which Blender 3.1.0 file did you use. Was it the .zip portable file? I used the first one under "Assets:" on this page here:
https://github.com/nalexandru/BlenderCompat/releases

Did you perhaps install something else that I didn't? For example, did you place the bcompat7.lib and bcompat7.dll files in a folder somewhere?

[Kieruss]

I also see the correct animation (Win7 Pro SP1 64bit). All I did was extract the zip, and run blender.exe. The bcompat7.dll is only in the extracted location (not moved). There is no bcompat7.lib. It looks like you've extracted the source, since that file is there... Try downloading and/or extracting the zip again, into a clean directory?

[nalexandru]

@BubbaBoBobSmith Only bcompat7.dll is needed for running Blender, the .lib is for compiling it. The file is included in the release archive, blender-3.1.0-windows-7.zip under Assets. This zip has all you need to run Blender, what you did (extracting and double-clicking blender.exe) is correct.

I was unable to reproduce your issue on 2 machines, and seeing that it works for others, the only things that come to mind are drivers and Windows updates. Do you have SP1 with the may 2016 rollup installed and the latest drivers (especially for the GPU) ?

Have you tried running 2.93 or 3.0 ? Between 2.93 and 3.0 OpenCL was dropped, i'm not sure if it has anything to do with Mantaflow but it would be helpful to know when it broke.

I will try to reproduce on a clean Windows 7 install.

[BubbaBoBobSmith]

Okay, I just finished more tests (My Windows 7 is Win 7 Pro 6.1.7601 SP 1, Build 7601).

I successfully installed the Win7-64 KB3156417 May 2016 update that you mentioned from the MS site, rebooted, and tried both Blender 3.0.0 and 3.1.0 again. Still no go for either version of Blender.

The Quick Explode works but Quick Liquid won't show any particles.

I think you may be on to something with the video drivers. I say that because when I tried running Blender 3.1.0. on my Win 10 laptop, I got a message saying that it was going to dumb Blender down a bit since that laptop's video circuitry was barely adequate.

Now I didn't get that warning on the Windows 7 boxes, but I can't help but wonder whether or not Blender 3.x automatically disables functions that are considered too 'heavy' for the machine that it's being installed on (whereas maybe 2.9.2 doesn't care and lets you calculate particles, regardless). Just a theory since the two Win 7 boxes that I'm using are fairly old by today's standards.

[Loriem]

Which Blender 3.1.0 file did you use.

I use the build of my own compiling, but made according to the instructions by nalexandru.
It is uploaded onto Dropbox (link here on the main page).
You can try it, but I don't think there are any major differences.
You can also try 3.2.0 alpha at the same link to see what happens.

[BubbaBoBobSmith]

Thanks! Do you mean the ones with the modified date of 2022-03-12 located here? https://www.dropbox.com/sh/eufffe60fvtr9mz/AAA0YtogOoJTKggWtgAXRyXJa?dl=0

I'm using an Intel CPU. Do you think the AMD version of Blender 3.2.0 Alpha will work on that box?

[Loriem]

I named the file exactly as it is called on the Blender website. AMD64 - in this case, it's just a bitness of the program (Blender), that is, this file is for the 64-bit version of Windows 7.

Do you mean the ones with the modified date of 2022-03-12 located here?

Right.

[BubbaBoBobSmith]

Well, I tried those files (including the Alpha 3.2.0 on both Windows 7 machines). Still no go with the liquid particles.

I'm not sure if it's important or not, but when I try those on the Windows 10 laptop, the liquid simulation runs, but it seems almost scaled-back compared to what I get in 2.9.2 (and compared to the video that you attached). Whereas the video and 2.9.2 both show lots of blue particles flowing around, my Win 10 laptop just shows a few yellow and orange particles. Odd.

The warning that I get on the Win 10 laptop is "Your graphics card has limited support." (which made me suspect that maybe some functionality is limited, based on what Blender finds when it scans for video hardware on startup). I didn't get any messages on the Windows 7 boxes, but maybe there's something similar going on there too?

[Loriem]

Try to start by looking at the following information (i.e. verifying that the hardware meets the system requirements), including any available links that are relevant to your situation. Maybe there is some answer.
https://www.blender.org/download/requirements/

[BubbaBoBobSmith]

Thanks. One of the two Win 7 towers has acceptable GPU stats.

Of course there's the very likely possibility that particles in Blender are handled by the CPU. So maybe that's the issue.

Anyway, I'm glad it's working on other people's machines. That means that the portable .zip of Blender is probably working just fine.

Again, thanks to everyone who made it possible to run the latest versions of Blender in Windows 7. You've done a great thing. I sure hope the Blender devs keeps on with these portable zip files. They're the cat's meow.

[nalexandru]

I tried reproducing your issue in a virtual machine with a clean install of Windows 7 SP1 + the May 2016 rollup and on a older machine with a Core 2 Duo T9400 and a GT 9600M. Both systems simulated the particles, albeit slowly at around 12 FPS.
The NVIDIA driver i used was 342.01, the newest version to support that GPU.

I didn't get the warning you mentioned on the old machine. What hardware are you using on the machines where it doesn't work ?

[regtable]

just like to butt in but 3.0 maybe 3x+ also has same issues.
i notice quick liquid sometimes does not set up the domain and inflow object correctly it does not spawn in the fluid particle system. to see it go to the domain particle tab if there isnt a fluid particle system ther remove the domain modifier and add it in manually then check to see its done it correctly.

[BubbaBoBobSmith]

The two machines that are giving me trouble with the fluid sim are:

HPxw8600
Dual Intel Xeon E5440 CPUs at 2.8 GHz each
24 GB RAM
NVIDIA QuadroFX 3800 (1GB video RAM)

---

HP Compaq 8200 Elite (larger form-factor tower)
i5-2500 3.3 GHz, 4 cores
8 GB RAM
AMD Radeon HD 6570 (1GB video RAM)

[nalexandru]

@BubbaBoBobSmith
I don't have access to either one of the GPUs you mentioned. The 9650M i have is a Tesla 1 card and the QuadroFX 3800 is a Tesla 2 card so they should be close in terms of supported features. I tried reproducing the issue with multiple driver releases, without success. Driver versions earlier than 260.99 cause Blender to crash on startup while 260.99 and newer simulate the particles.

However, both of your GPUs (and my 9650M) do not meet the minimum requirements, which are "Graphics card with 2 GB RAM, OpenGL 4.3". The FX3800 supports OpenGL 3.3, and both have 1 GB of vRAM.

[BubbaBoBobSmith]

I suppose only the person (or people) who did the Mantaflow component of Blender would know what's keeping that particular part of the Blender physics system from executing properly.

However, even though I can't get the fluid simulation to run, I'm still happy that the core of Blender works. After all, that alone allows for access to file load, edit, and save capabilities for conventional Blender 3.x models and associated assets on older Win 7 machines. Very handy -- in addition to being able to keep up with the interface changes.

Thanks again for looking into this.