Real-Time Body Physics (RTBP) by CPVC

Version v2.2~4 - May 4 2026

Disclaimer

Play with this at your own risk. I recommend you back up your save files or start a new throw-away game before trying it. I am not liable for any damage this mod does to your computer.

Installation

  1. Move "d3d11.dll" to "...\[TS4_INSTALL_DIR]\Game\Bin\". It should be in the same directory as "TS4_x64.exe". Currently, this mod only works with the 64 bit version of The Sims 4.
  2. Move "RTBP" to "...\[MY_DOCUMENTS]\Electronic Arts\The Sims 4\". This directory will house your settings file and log file once it is generated.
  3. Copy the folder "RTBP Mod" to "...\[MY_DOCUMENTS]\Electronic Arts\The Sims 4\Mods\".
  4. ReShade: Newer versions of ReShade no longer conflict with RTBP. Install RTBP first, then install ReShade. That's it.

RTBP GUI

Press F11 to open the RTBP GUI. The GUI can be used to configure RTBP without dirtying your hands manually editing settings files.

Settings

It is recommended that you use the RTBP GUI to modify your settings. It's easier and you can see your changes in real time.

The settings file, located at ...\[MY_DOCUMENTS]\Electronic Arts\The Sims 4\RTBP\Settings.ini" can be modified to change the behavior of the mod.

The section "rtbp.general" is for general settings of the mod, like if you want to start the debug command server or if you want to enable/disable breast and butt physics.

The section "rtbp.leftBreast" sets the settings that control the spring physics of the left breast. If you don't know what these settings do, please read the next section "Simulation Settings".

I think the rest is self-explanatory.

Advanced Settings: Debug Flags

You can skip this section if you don't want to mess around with debug flags. Most people probably won't.

Debug flags can be set in your settings file, but they're a special case compared to other settings. Debug flags need to be explicitly defined to make them persist in your settings file. When saving your settings file, your "[rtbp.debugFlags]" section will be transfered over, but any debug flags you set using the Commander or through manually entering commands will not be written to your settings file.

This is for safety. Debug flags should not be taken lightly. Testing out alternate breasts and butt physics modes is usually ok, but some debug flags can crash your game or worse. Debug flags need to be tested first, but do this at your own risk. If you like what they do and everything is stable, you may enable debug flags in your settings file.

The default value for every debug flag is "false". As soon as a debug flag is referenced in RTBP, it will be defined and will show up in the commander. If you add an entry to your "[rtbp.debugFlags]" section, but set the value to "false", the entry will be completely ignored.

Debug flags are subject to change and you cannot rely on them working the same way or even existing across different versions of RTBP.

Simulation Variables

RTBP is based off spring physics. The following settings can be modified through the GUI or by editing the settings file.

Linear

Angular

Postscript

Thank you for helping me develop RTBP through your bug reports, suggestions, and other feedback.

This file has been automatically generated. Please let me know if there are any mistakes. Thanks!