wip Real-Time Body Physics (DirectX 11)

[CPVC]

11 hours ago, kyojin77 said:

Damn. OK, thanks for the info. I guess I have to uninstall the mod for now. Good luck!

 

Thanks. I'll do another proper release once I'm sure I've fixed it.

[CPVC]

I've gotten RTBP to build with Clang in MSVC compatibility mode. This is the compiler Google uses to build Chrome.

 

The cool thing about using Clang instead of MingW (the compiler I've been using to build RTBP up until now) is that Clang tries to be compatible with Microsoft's compiler, MSVC, and can link with Windows' standard library. This means that the resulting DLL is smaller, possibly more stable, and maybe even faster.

 

It's possible that this build could work for the users that have been having problems getting RTBP to work if the problem was with the compiler. Please try it out and let me know if it works. It is currently untested in Windows, but it's been running like a top for me in Linux. Absolutely no problems whatsoever.

 

A couple of changes between this experimental version and the last one:

 

* Reverted breasts center calculating back to fixed centers. This wasn't working for meshes with extra geometry on the breasts, like extravagant outfits or costumes.

 

* Shout out to patrons. As a special thank you to those who support RTBP, their names appear next to the logo upon starting the Sims 4 with RTBP installed. Thanks for the support.

 

* Sims tab. I think this was part of the last experimental release, but I didn't mention it. In the GUI, check out the "Sims" tab. You can mess with the simulators directly and watch their values change as the simulation runs. Click an address (0x123456) button to show the controls for that simulator. Check "Lock" to lock the values and drag the sliders to change values. Ctrl + click allows you to enter in a value directly.

 

Think that's it.

 

RTBP v2.2~4 2026-05-04 (Clang-CL).zip

 

Edited May 5 by CPVC

[APassingGhost]

On 5/5/2026 at 11:22 AM, CPVC said:

I've gotten RTBP to build with Clang in MSVC compatibility mode. This is the compiler Google uses to build Chrome.

 

The cool thing about using Clang instead of MingW (the compiler I've been using to build RTBP up until now) is that Clang tries to be compatible with Microsoft's compiler, MSVC, and can link with Windows' standard library. This means that the resulting DLL is smaller, possibly more stable, and maybe even faster.

 

It's possible that this build could work for the users that have been having problems getting RTBP to work if the problem was with the compiler. Please try it out and let me know if it works. It is currently untested in Windows, but it's been running like a top for me in Linux. Absolutely no problems whatsoever.

 

A couple of changes between this experimental version and the last one:

 

* Reverted breasts center calculating back to fixed centers. This wasn't working for meshes with extra geometry on the breasts, like extravagant outfits or costumes.

 

* Shout out to patrons. As a special thank you to those who support RTBP, their names appear next to the logo upon starting the Sims 4 with RTBP installed. Thanks for the support.

 

* Sims tab. I think this was part of the last experimental release, but I didn't mention it. In the GUI, check out the "Sims" tab. You can mess with the simulators directly and watch their values change as the simulation runs. Click an address (0x123456) button to show the controls for that simulator. Check "Lock" to lock the values and drag the sliders to change values. Ctrl + click allows you to enter in a value directly.

 

Think that's it.

 

RTBP v2.2~4 2026-05-04 (Clang-CL).zip 6.07 MB · 8 downloads

 

 

So uh

 

I wasn't having issues with the compiler? But I think this build might be causing my game to "stop responding"

 

I had a weird issue from Saturday morning til about this morning that I think only started when I replaced the 04-21 build with this one? And I only figured it when removing or replacing the d11 file stopped the freezing

 

I could be wrong - I'm still testing this myself, but I figured I'd give a heads up because no other mod seems to be causing the issue (removed all other mods to check)

 

If it's at all relevant, I'm a Windows user on the newest version of the game (as of writing, this is pre-May 12 patch)

[APassingGhost]

Update: Now that I've tested it with the older build, I can confirm that it is indeed the new Clang build of RTBP that's causing my issues

[jeno3]

Hi CPVC, 

 

I’ve attached a video. Please take a look at it. It consists solely of poses, but please observe what is happening there. Unfortunately, I’m not sure if the issue lies with the rig used by the pose creator. I’m just a bit confused, since the coordinate system remains fixed—or does it actually change depending on the Sim's orientation?

 

This is the  Test-Version (DLL) from 21.04.2026

 

Other

Breast_Gravity 2026-05-11 22-52-31-455.rar

[CPVC]

14 hours ago, APassingGhost said:

Update: Now that I've tested it with the older build, I can confirm that it is indeed the new Clang build of RTBP that's causing my issues

 

Hmmm, ok. Well, new compiler, new problems, I guess. Does your log file say anything when it freezes? Mind sharing it? It's possible a swich to Clang is a step in the wrong direction. I just wanted to see if it improved anything for those that were having problems and see if there were other benefits. In my testing, it seems to be more stable.

 

3 hours ago, jeno3 said:

Hi CPVC, 

 

I’ve attached a video. Please take a look at it. It consists solely of poses, but please observe what is happening there. Unfortunately, I’m not sure if the issue lies with the rig used by the pose creator. I’m just a bit confused, since the coordinate system remains fixed—or does it actually change depending on the Sim's orientation?

 

This is the  Test-Version (DLL) from 21.04.2026

 

Other

Breast_Gravity 2026-05-11 22-52-31-455.rar 3.84 MB · 0 downloads

 

It is fixed. Down should always be down regardless of orientation, but the coordinates I was using for linear physics are incorrect. I need to redo them with what I learned implementing angular physics. Try using the direct translation of the breast bones for linear physics calculations. Enable the debug flag "testAltBreastPhysics1". I'll get them working exactly as they should for the next release.

 

[APassingGhost]

14 hours ago, CPVC said:

 

Hmmm, ok. Well, new compiler, new problems, I guess. Does your log file say anything when it freezes? Mind sharing it? It's possible a swich to Clang is a step in the wrong direction. I just wanted to see if it improved anything for those that were having problems and see if there were other benefits. In my testing, it seems to be more stable.

 

 

It is fixed. Down should always be down regardless of orientation, but the coordinates I was using for linear physics are incorrect. I need to redo them with what I learned implementing angular physics. Try using the direct translation of the breast bones for linear physics calculations. Enable the debug flag "testAltBreastPhysics1". I'll get them working exactly as they should for the next release.

 

 

As of right now, I am unable to replicate the problem? I have a log file, but the log file is only from my most recent attempt to replicate this issue. I'm not sure if it's much help, but I'll provide it anyway

 

Note: I've modified it to remove my name, as I prefer to stay anonymous.

Log.txt

[APassingGhost]

Addendum: I only had to try and replicate the issue because I downgraded to the earlier build and have been playing on that since yesterday. Apologies.

[APassingGhost]

Update: By some...miracle? The error managed to happen again. Here's my log file for reference: Log.txt 

[asdurgico]

I tested the new Clang version for half an hour and i didn't have any CTD, before i was getting a lot of crashes so at least for me this version is much better!

[jeno3]

The Clang version doesn't work for me. The game loads up to the home screen, but when I try to load a household, it crashes. I am currently playing the game in windowed mode; perhaps that has something to do with it. However, if it works for some people but not for others, it might be a good idea to offer two different versions.

[CPVC]

21 hours ago, jeno3 said:

The Clang version doesn't work for me. The game loads up to the home screen, but when I try to load a household, it crashes. I am currently playing the game in windowed mode; perhaps that has something to do with it. However, if it works for some people but not for others, it might be a good idea to offer two different versions.

 

I could do that, but it would be nice to standardize on one compiler if I can. Make sure to submit error reports when it crashes.

[jeno3]

On 5/12/2026 at 2:45 AM, CPVC said:

t is fixed. Down should always be down regardless of orientation, but the coordinates I was using for linear physics are incorrect. I need to redo them with what I learned implementing angular physics. Try using the direct translation of the breast bones for linear physics calculations. Enable the debug flag "testAltBreastPhysics1". I'll get them working exactly as they should for the next release.

 

I tried it with "testAltBreastPhysics1." Unfortunately, that didn't change anything. However, it is interesting to observe: the more the legs are bent, the more the breasts pull in that direction. When the Sim is lying on their stomach, with their legs stretched out, straight the breasts move toward the floor; in this case, "down" actually means down. I hope you manage to fix this. Thanks for everything!

[Quabn]

I really like this mod but I'm having a problem with the DX11 version.

 

The game always become unresponsive when I use DX11 version, even after removing all mods, it's still the same problem. I tried waiting it out and the problem still persist forcing me to close it.

 

The game run fine with DX9.

 

[CPVC]

16 hours ago, Quabn said:

I really like this mod but I'm having a problem with the DX11 version.

 

The game always become unresponsive when I use DX11 version, even after removing all mods, it's still the same problem. I tried waiting it out and the problem still persist forcing me to close it.

 

The game run fine with DX9.

 

 

Hmmm. Mind sharing your log file? I'll take a gander at it and see if I can figure out what's up.

[Quabn]

2 hours ago, CPVC said:

 

Hmmm. Mind sharing your log file? I'll take a gander at it and see if I can figure out what's up.

Here ya go

 

I did went back to DX9, do I need to do another DX11 again play to generate new log tho for the problem?

 

I run the game with DX11 again and generated another log, just to be sure.

Log.txt

Log - DX11.txt

Edited May 23 by Quabn

[CPVC]

20 hours ago, Quabn said:

Here ya go

 

I did went back to DX9, do I need to do another DX11 again play to generate new log tho for the problem?

 

I run the game with DX11 again and generated another log, just to be sure.

Log.txt 12.52 kB · 1 download

Log - DX11.txt 20.79 kB · 1 download

 

Yes the DX11 version was needed, thanks for getting that. I don't see anything off in your log. It looks like everything is working until a new input layout is detected and it locks up. Here is a build made with a different compiler. Try this out and see if it works.

 

RTBP v2.3~1 2026-05-23 (MinGW).zip

 

jeno3, here's a MinGW build of the latest version. It might work for you, too.

 

On 5/15/2026 at 3:08 AM, jeno3 said:

The Clang version doesn't work for me. The game loads up to the home screen, but when I try to load a household, it crashes. I am currently playing the game in windowed mode; perhaps that has something to do with it. However, if it works for some people but not for others, it might be a good idea to offer two different versions.

 

[Quabn]

28 minutes ago, CPVC said:

 

Yes the DX11 version was needed, thanks for getting that. I don't see anything off in your log. It looks like everything is working until a new input layout is detected and it locks up. Here is a build made with a different compiler. Try this out and see if it works.

 

RTBP v2.3~1 2026-05-23 (MinGW).zip 6.31 MB · 1 download

 

jeno3, here's a MinGW build of the latest version. It might work for you, too.

 

 

So I tried the MinGW build and it's the same problem, game freeze and become unresponsive. I taken off every mod except 'RTBP Mod' folder ofc then try again on vanilla and it's still the same (I also delete the localthumbcache.package just to be sure). I'm going to leave both Vanilla and Modded log file here and keep on trying with some tweak like lower the graphics.

Log - Modded.txt Log - Vanilla.txt

[CPVC]

1 hour ago, Quabn said:

So I tried the MinGW build and it's the same problem, game freeze and become unresponsive. I taken off every mod except 'RTBP Mod' folder ofc then try again on vanilla and it's still the same (I also delete the localthumbcache.package just to be sure). I'm going to leave both Vanilla and Modded log file here and keep on trying with some tweak like lower the graphics.

Log - Modded.txt 20.24 kB · 0 downloads Log - Vanilla.txt 21.15 kB · 0 downloads

 

Hmmm, something to do with copying the vertex and index buffers back to the GPU after analyzing and modifying... Try this build here. This is a "read-only" build of RTBP. Vertex and index buffers won't be modified and written back to the GPU and butt simulators are disabled. It might work. You'll need to manually install the DLL. Just copy the new one over the old one in your "...\The Sims 4\Game\Bin\" folder.

 

RTBP 2.3~1 2026-05-23 (Read Only).zip

[Quabn]

2 hours ago, CPVC said:

 

Hmmm, something to do with copying the vertex and index buffers back to the GPU after analyzing and modifying... Try this build here. This is a "read-only" build of RTBP. Vertex and index buffers won't be modified and written back to the GPU and butt simulators are disabled. It might work. You'll need to manually install the DLL. Just copy the new one over the old one in your "...\The Sims 4\Game\Bin\" folder.

 

RTBP 2.3~1 2026-05-23 (Read Only).zip 1.55 MB · 0 downloads

Nope, still the same problem.

 

i'm gonna try to completely reinstall the game to check.

Log - Read Only Butt simulator Off.txt

[Quabn]

Hello I'm back with the same problem after reinstalling the game

 

I tried the stable DX11 version first then the MinGW build and the Read only build

 

All result in the same problem 

Log - MinGW.txt Log - Read Only.txt Log - stable DX11.txt

[CPVC]

11 hours ago, Quabn said:

Hello I'm back with the same problem after reinstalling the game

 

I tried the stable DX11 version first then the MinGW build and the Read only build

 

All result in the same problem 

Log - MinGW.txt 21.22 kB · 0 downloads Log - Read Only.txt 13.97 kB · 0 downloads Log - stable DX11.txt 22.57 kB · 0 downloads

 

Well, darn. It does look like there's a pattern here, which at least points me in the right direction. When it freezes it's almost always related to the copying of buffers. I'll try to improve the debugging around that and see if I can get more information on what's going on. In the mean time, I'm afraid you are stuck with DX9 version. Sorry about that.

[Quabn]

6 hours ago, CPVC said:

 

Well, darn. It does look like there's a pattern here, which at least points me in the right direction. When it freezes it's almost always related to the copying of buffers. I'll try to improve the debugging around that and see if I can get more information on what's going on. In the mean time, I'm afraid you are stuck with DX9 version. Sorry about that.

Oh, one question.

 

Does playing in Fullscreen\Borderless mode affect anything?

[jeno3]

On 5/24/2026 at 2:06 AM, CPVC said:

jeno3, here's a MinGW build of the latest version. It might work for you, too.

I just tested it. It runs stably.

[0Spirit0]

15 hours ago, Quabn said:

Oh, one question.

 

Does playing in Fullscreen\Borderless mode affect anything?

I only got this mod working well in windowed and borderless mode

 

Spoiler

 

 

Edited May 25 by 0Spirit0