wip Real-Time Body Physics (DirectX 11)

[jeno3]

Jiggle_Shoulders2026-06-06 14-33-52-871.rar

[Reddud3]

On 5/24/2026 at 11:45 PM, 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.

I'm experiencing the same issue. I've been having this issue on older versions too. I'm not sure I've ever been able to use the DX11 version, as I keep crashing when entering CAS after clicking 'edit household'. I've sent three crashes via the error reporter, one for the latest Clang version, the MinGW build and the read-only version. Hope they help!

[Overdraft0213]

Already 15 mins in the game and the logo isn't disappearing for me somehow. It happens randomly, really, sometimes it does dissapear and sometimes it doesn't


I have already set the RTBP logo to off in the settings

[CPVC]

4 hours ago, Overdraft0213 said:

Already 15 mins in the game and the logo isn't disappearing for me somehow. It happens randomly, really, sometimes it does dissapear and sometimes it doesn't


I have already set the RTBP logo to off in the settings

 

Yeah, I did some refactoring before this release and messed something up. Just leave "Show RTBP Logo At Startup?" checked for the time being and it will go away after 5 seconds. Sorry about that. It'll be fixed in the next experimental release.

[yty001]

excuse me how can i solve this problem?

日誌.txt

Edited June 12 by yty001

[CPVC]

9 hours ago, yty001 said:

excuse me how can i solve this problem?

日誌.txt

 

This is a known issue related to scaling the GUI. If the window size is too small, ImGUI, the UI library I'm using, is unable to render. I guess for now, don't let the window get too small. I'll come up with a fix that prevents this from happening in the future.

[yty001]

2 hours ago, CPVC said:

 

這是一個已知的與圖形使用者介面縮放相關的問題。如果視窗尺寸太小，我使用的使用者介面庫 ImGUI 就無法渲染。所以目前來說，最好不要讓視窗尺寸太小。我會盡快找到解決方案，防止將來再次出現這個問題。

thank you

[CPVC]

There is a possibility that this build here might work for those of you that are having trouble getting RTBP to work. I've studied other projects that work similarly to RTBP and found that they all export about 40 functions that have been unavailable in RTBP so far. I've made them available as proxy functions that simply pass through RTBP to the system d3d11.dll. This could work or at least help. If you're having issues, please try this out and let me know if it works or not. This is just the DLL, so you will have to manually install.

 

RTBP v.2.3~2 2026-06-12 (Forward Functions).zip

[APassingGhost]

11 hours ago, CPVC said:

There is a possibility that this build here might work for those of you that are having trouble getting RTBP to work. I've studied other projects that work similarly to RTBP and found that they all export about 40 functions that have been unavailable in RTBP so far. I've made them available as proxy functions that simply pass through RTBP to the system d3d11.dll. This could work or at least help. If you're having issues, please try this out and let me know if it works or not. This is just the DLL, so you will have to manually install.

 

RTBP v.2.3~2 2026-06-12 (Forward Functions).zip 1.57 MB · 1 download

I tried the new build and uhhh loading up one of my households caused the game to instantly close itself

Log.txt

I'll look more into it next week after my assignments but in the meantime, here's my log if that tells you anything

[CPVC]

6 hours ago, APassingGhost said:

I tried the new build and uhhh loading up one of my households caused the game to instantly close itself

Log.txt 5.65 kB · 0 downloads

I'll look more into it next week after my assignments but in the meantime, here's my log if that tells you anything

 

Thanks for testing it. I have made arrangements to test RTBP on other machines so hopefully I can get to the bottom of why it works on some machines and not others.

[yokozii]

Ive been away awhile , saw the patreon update for the new build. excited to try it once I update my game 

[shinichi104]

33 minutes ago, yokozii said:

Ive been away awhile , saw the patreon update for the new build. excited to try it once I update my game 

SO glad to hear from you!!!! glad you are doing ok!!

[APassingGhost]

17 hours ago, CPVC said:

 

Thanks for testing it. I have made arrangements to test RTBP on other machines so hopefully I can get to the bottom of why it works on some machines and not others.

 

Yeah no it's definitely something of RTBP - Tried with a different household and the game force quit again unfortunately

[CPVC]

7 hours ago, APassingGhost said:

 

Yeah no it's definitely something of RTBP - Tried with a different household and the game force quit again unfortunately

 

Bummer. Well, worth a shot I guess. Like I said in my earlier post, I'm going to be testing RTBP out on some other machines soon. Just waiting on the machines being available.

[jeno3]

Hi,

 

my Game crashed with the Version (Forward Functions). First it runs, but after a view minutes....Game Over

Log.txt

[jeno3]

But there’s something else, too. Please take a look at this video. It’s the linear physics causing this, not the angular ones. The larger the breasts, the worse it gets. Maybe you can get a handle on that? Otherwise, I’ll look forward to your next experiment, which sounds very promising. I hope everything works out the way you—and all of us—hope it will. I’m glad you’re staying so dedicated to this.

bandicam 2026-06-17 12-14-52-135.rar

[CPVC]

17 hours ago, jeno3 said:

But there’s something else, too. Please take a look at this video. It’s the linear physics causing this, not the angular ones. The larger the breasts, the worse it gets. Maybe you can get a handle on that? Otherwise, I’ll look forward to your next experiment, which sounds very promising. I hope everything works out the way you—and all of us—hope it will. I’m glad you’re staying so dedicated to this.

bandicam 2026-06-17 12-14-52-135.rar 55.89 MB · 1 download

 

The "forward functions" variant is a little wonky. It's based on my work in progress code and I've probably screwed up the matrix multiplication order again. I'll fix it and release a new build with the forwarded functions if it's actually helping.

[奇怪的花裤衩学长]

I don't quite understand this Mod feature. I don't even understand its movement logic. As long as the character makes even the slightest movement, this breast will keep bouncing like a perpetual motion machine. Even if the character is standing still, this breast keeps bouncing endlessly, seemingly never getting tired. However, it doesn't perform well on a treadmill. It's not a breast at all, nor does it conform to "physics". It doesn't resemble a cute jelly or a balloon filled with water. It's just a perpetual motion machine that keeps bouncing. If you have a better setting method, I'm currently using the author's default settings. Until there is a better solution, I think this Mod is not mature enough, at least it feels that way to me now. Moreover, it conflicts severely with WW animations, which themselves have a "pseudo-physical" jitter effect. So it will only exacerbate the jitter, making it unreasonable. But... I really want to localize it for translation, so that I can gradually study it in the game. However, it doesn't seem as easy as other Mods.
 

[CPVC]

15 hours ago, 奇怪的花裤衩学长 said:

I don't quite understand this Mod feature. I don't even understand its movement logic. As long as the character makes even the slightest movement, this breast will keep bouncing like a perpetual motion machine. Even if the character is standing still, this breast keeps bouncing endlessly, seemingly never getting tired. However, it doesn't perform well on a treadmill. It's not a breast at all, nor does it conform to "physics". It doesn't resemble a cute jelly or a balloon filled with water. It's just a perpetual motion machine that keeps bouncing. If you have a better setting method, I'm currently using the author's default settings. Until there is a better solution, I think this Mod is not mature enough, at least it feels that way to me now. Moreover, it conflicts severely with WW animations, which themselves have a "pseudo-physical" jitter effect. So it will only exacerbate the jitter, making it unreasonable. But... I really want to localize it for translation, so that I can gradually study it in the game. However, it doesn't seem as easy as other Mods.
 

 

The linear physics system was recently revamped and the default settings need tweaking. Increase damping to get movement to stop faster, decrease spring K to lower springiness of simulations. For the best experience at this time, I recommend using just angular physics until I can get them to play well together. If you are using the DirectX 9 version of RTBP, that has been depreciated and is no longer being updated and does not include the newest features of RTBP.

 

Sims running on the treadmill don't look super good because at this time simulations are calculated in local space, i.e. relative to the sim's body. If there is not a lot of movement in the parent bone, you won't see much activity in the physics simulations. For some reason, sims seem to have ridiculously good posture when running, so you're not going to see much breast bounce there.

 

Try jogging maybe? I think it looks pretty darn good with just angular physics:

 

https://files.catbox.moe/04qh4u.webm

[ArtEdit]

Hi, first of all, thank you for developing this mod.

I recently upgraded my graphics card from an NVIDIA RTX 1060 to an NVIDIA RTX 5060. Before the upgrade, the mod worked perfectly.

The issue is that when I run the game in exclusive fullscreen mode, everything works fine. However, if I switch to windowed mode or borderless fullscreen, the game crashes. It also crashes if I minimize the game using the Windows key or Alt+Tab.

I believe the issue is related to this mod because if I disable it, I can switch between fullscreen, windowed, and borderless modes, as well as Alt+Tab and minimize the game without any crashes.

I've attached the log file.

Log.txt

Edited June 28 by ArtEdit

[RavenTwain]

On 4/28/2026 at 10:54 PM, CPVC said:

 

Oh, I see, you're running 2.2. You don't have the new GUI. In 2.2, linear physics have to be enabled with debug flags. Press "F11" to open the GUI, click the "Debug Flags" tab, find and check the flag that says "enableLinearPhysics" to enable linear physics.

 

After that the "Test Linear (X|Y|Z)" buttons should work. You can use linear physics at the same time as angular physics, or you can disable angular to just have linear. Check the debug flag "disableAngularPhysics" to do this.

 

In the next version, the GUI will look like this:

 

 

Linear, angular, and exaggeration can be enabled/disabled for each simulator.

I do not have this option:
My 'Companion' app/program and default settings is from May, 2026. Saving with the GUI removes all aspects of 'exaggerate' from said file too. If this is the same as disabling it, than i have no issue/need to fix fn. lol

Edited June 28 by RavenTwain
added context

[jeno3]

18 hours ago, ArtEdit said:

Hi, first of all, thank you for developing this mod.

I recently upgraded my graphics card from an NVIDIA RTX 1060 to an NVIDIA RTX 5060. Before the upgrade, the mod worked perfectly.

The issue is that when I run the game in exclusive fullscreen mode, everything works fine. However, if I switch to windowed mode or borderless fullscreen, the game crashes. It also crashes if I minimize the game using the Windows key or Alt+Tab.

I believe the issue is related to this mod because if I disable it, I can switch between fullscreen, windowed, and borderless modes, as well as Alt+Tab and minimize the game without any crashes.

I've attached the log file.

Log.txt 6.29 kB · 1 download

I had this problem too. Try the following: Remove the DLL file from the Game-Bin folder. Then start the game and change your mode. After that, exit the game and put the DLL back in the folder. That’s how it worked for me; I only use windowed mode. If you do it this way, you can minimize the game without it crashing.

[ArtEdit]

2 hours ago, jeno3 said:

I had this problem too. Try the following: Remove the DLL file from the Game-Bin folder. Then start the game and change your mode. After that, exit the game and put the DLL back in the folder. That’s how it worked for me; I only use windowed mode. If you do it this way, you can minimize the game without it crashing.

I already tried that, but if I start the game in either windowed or borderless windowed mode, it crashes right after the RTBP logo appears.

[Quabn]

So I also have the same problem with DX11 version

 

While playing in Fullscreen everything seem fine until I Alt+Tab out and then get this message

[CPVC]

On 6/28/2026 at 2:47 AM, ArtEdit said:

Hi, first of all, thank you for developing this mod.

I recently upgraded my graphics card from an NVIDIA RTX 1060 to an NVIDIA RTX 5060. Before the upgrade, the mod worked perfectly.

The issue is that when I run the game in exclusive fullscreen mode, everything works fine. However, if I switch to windowed mode or borderless fullscreen, the game crashes. It also crashes if I minimize the game using the Windows key or Alt+Tab.

I believe the issue is related to this mod because if I disable it, I can switch between fullscreen, windowed, and borderless modes, as well as Alt+Tab and minimize the game without any crashes.

I've attached the log file.

Log.txt 6.29 kB · 1 download

 

Try this build here. It might do the trick. Do a manual install. This build is similar to the last one, but makes more of the system DLL functions available through RTBP. I think I'm on the right track with that, but I'm not sure about this implementation.

 

RTBP v2.3~3 2026-06-29.zip

 

17 hours ago, Quabn said:

So I also have the same problem with DX11 version

 

While playing in Fullscreen everything seem fine until I Alt+Tab out and then get this message

 

This issue has been fixed in the attached build I believe. It will be part of the next release.