p.Chaos.ImmPhys.Joint.SoftTwistStiffness
p.Chaos.ImmPhys.Joint.SoftTwistStiffness
#Overview
name: p.Chaos.ImmPhys.Joint.SoftTwistStiffness
This variable is created as a Console Variable (cvar).
- type:
Var - help:
6Dof joint SoftTwist stiffness override (if > 0).
It is referenced in 4 C++ source files.
#Summary
#Usage in the C++ source code
The purpose of p.Chaos.ImmPhys.Joint.SoftTwistStiffness is to override the soft twist stiffness for 6-degree-of-freedom (6DoF) joints in the Chaos Immediate Physics system of Unreal Engine 5.
This setting variable is part of the Chaos physics engine, specifically the Immediate Physics simulation module. It is used in the physics engine’s joint system to control the stiffness of the twist motion in soft constraints.
The value of this variable is set through the Unreal Engine console variable system. It’s defined as an FAutoConsoleVariableRef, which allows it to be modified at runtime through console commands or configuration files.
The associated variable ChaosImmediate_Joint_SoftTwistStiffness interacts directly with p.Chaos.ImmPhys.Joint.SoftTwistStiffness. They share the same value, with ChaosImmediate_Joint_SoftTwistStiffness being the actual variable used in the physics simulation code.
Developers must be aware that this variable only takes effect when its value is greater than 0. If it’s set to a negative value (default is -1.0f), it won’t override the default soft twist stiffness of the joint.
Best practices when using this variable include:
- Only modify it if you need to fine-tune the joint behavior across all 6DoF joints in your simulation.
- Use it for debugging or prototyping, but consider setting joint properties individually for production use.
- Be cautious when changing this value, as it can significantly affect the stability and behavior of your physics simulation.
Regarding the associated variable ChaosImmediate_Joint_SoftTwistStiffness:
- It’s a Chaos::FRealSingle (likely a float) used internally by the physics engine.
- It’s initialized to -1.0f, meaning no override by default.
- It’s used in the FSimulation::Simulate function to set the SoftTwistStiffnessOverride of the JointsSettings.
- Changing this variable directly is not recommended; instead, modify it through the console variable system using p.Chaos.ImmPhys.Joint.SoftTwistStiffness.
#References in C++ code
#Callsites
This variable is referenced in the following C++ source code:
#Loc: <Workspace>/Engine/Source/Runtime/Engine/Private/PhysicsEngine/ImmediatePhysics/ImmediatePhysicsChaos/ImmediatePhysicsSimulation_Chaos.cpp:126
Scope: file
Source code excerpt:
FAutoConsoleVariableRef CVarChaosImmPhysJointStiffness(TEXT("p.Chaos.ImmPhys.Joint.Stiffness"), ChaosImmediate_Joint_Stiffness, TEXT("6Dof joint stiffness override (if > 0)."));
FAutoConsoleVariableRef CVarChaosImmPhysJointSoftLinearStiffness(TEXT("p.Chaos.ImmPhys.Joint.SoftLinearStiffness"), ChaosImmediate_Joint_SoftLinearStiffness, TEXT("6Dof joint soft linear stiffness override (if > 0)."));
FAutoConsoleVariableRef CVarChaosImmPhysJointSoftTwistStiffness(TEXT("p.Chaos.ImmPhys.Joint.SoftTwistStiffness"), ChaosImmediate_Joint_SoftTwistStiffness, TEXT("6Dof joint SoftTwist stiffness override (if > 0)."));
FAutoConsoleVariableRef CVarChaosImmPhysJointSoftTwistDamping(TEXT("p.Chaos.ImmPhys.Joint.SoftTwistDamping"), ChaosImmediate_Joint_SoftTwistDamping, TEXT("6Dof joint SoftTwist damping override (if > 0)."));
FAutoConsoleVariableRef CVarChaosImmPhysJointSoftSwingStiffness(TEXT("p.Chaos.ImmPhys.Joint.SoftSwingStiffness"), ChaosImmediate_Joint_SoftSwingStiffness, TEXT("6Dof joint SoftSwing stiffness override (if > 0)."));
FAutoConsoleVariableRef CVarChaosImmPhysJointSoftSwingDamping(TEXT("p.Chaos.ImmPhys.Joint.SoftSwingDamping"), ChaosImmediate_Joint_SoftSwingDamping, TEXT("6Dof joint SoftSwing damping override (if > 0)."));
FAutoConsoleVariableRef CVarChaosImmPhysJointLinearDriveStiffness(TEXT("p.Chaos.ImmPhys.Joint.LinearDriveStiffness"), ChaosImmediate_Joint_LinearDriveStiffness, TEXT("6Dof joint drive stiffness override (if > 0)."));
FAutoConsoleVariableRef CVarChaosImmPhysJointLinearDriveDamping(TEXT("p.Chaos.ImmPhys.Joint.LinearDriveDamping"), ChaosImmediate_Joint_LinearDriveDamping, TEXT("6Dof joint drive damping override (if > 0)."));
FAutoConsoleVariableRef CVarChaosImmPhysJointAngularDriveStiffness(TEXT("p.Chaos.ImmPhys.Joint.AngularDriveStiffness"), ChaosImmediate_Joint_AngularDriveStiffness, TEXT("6Dof joint drive stiffness override (if > 0)."));
#Associated Variable and Callsites
This variable is associated with another variable named ChaosImmediate_Joint_SoftTwistStiffness. They share the same value. See the following C++ source code.
#Loc: <Workspace>/Engine/Source/Runtime/Engine/Private/PhysicsEngine/ImmediatePhysics/ImmediatePhysicsChaos/ImmediatePhysicsSimulation_Chaos.cpp:102
Scope: file
Source code excerpt:
Chaos::FRealSingle ChaosImmediate_Joint_Stiffness = -1.0f;
Chaos::FRealSingle ChaosImmediate_Joint_SoftLinearStiffness = -1.0f;
Chaos::FRealSingle ChaosImmediate_Joint_SoftTwistStiffness = -1.0f;
Chaos::FRealSingle ChaosImmediate_Joint_SoftTwistDamping = -1.0f;
Chaos::FRealSingle ChaosImmediate_Joint_SoftSwingStiffness = -1.0f;
Chaos::FRealSingle ChaosImmediate_Joint_SoftSwingDamping = -1.0f;
Chaos::FRealSingle ChaosImmediate_Joint_LinearDriveStiffness = -1.0f;
Chaos::FRealSingle ChaosImmediate_Joint_LinearDriveDamping = -1.0f;
Chaos::FRealSingle ChaosImmediate_Joint_AngularDriveStiffness = -1.0f;
#Loc: <Workspace>/Engine/Source/Runtime/Engine/Private/PhysicsEngine/ImmediatePhysics/ImmediatePhysicsChaos/ImmediatePhysicsSimulation_Chaos.cpp:126
Scope: file
Source code excerpt:
FAutoConsoleVariableRef CVarChaosImmPhysJointStiffness(TEXT("p.Chaos.ImmPhys.Joint.Stiffness"), ChaosImmediate_Joint_Stiffness, TEXT("6Dof joint stiffness override (if > 0)."));
FAutoConsoleVariableRef CVarChaosImmPhysJointSoftLinearStiffness(TEXT("p.Chaos.ImmPhys.Joint.SoftLinearStiffness"), ChaosImmediate_Joint_SoftLinearStiffness, TEXT("6Dof joint soft linear stiffness override (if > 0)."));
FAutoConsoleVariableRef CVarChaosImmPhysJointSoftTwistStiffness(TEXT("p.Chaos.ImmPhys.Joint.SoftTwistStiffness"), ChaosImmediate_Joint_SoftTwistStiffness, TEXT("6Dof joint SoftTwist stiffness override (if > 0)."));
FAutoConsoleVariableRef CVarChaosImmPhysJointSoftTwistDamping(TEXT("p.Chaos.ImmPhys.Joint.SoftTwistDamping"), ChaosImmediate_Joint_SoftTwistDamping, TEXT("6Dof joint SoftTwist damping override (if > 0)."));
FAutoConsoleVariableRef CVarChaosImmPhysJointSoftSwingStiffness(TEXT("p.Chaos.ImmPhys.Joint.SoftSwingStiffness"), ChaosImmediate_Joint_SoftSwingStiffness, TEXT("6Dof joint SoftSwing stiffness override (if > 0)."));
FAutoConsoleVariableRef CVarChaosImmPhysJointSoftSwingDamping(TEXT("p.Chaos.ImmPhys.Joint.SoftSwingDamping"), ChaosImmediate_Joint_SoftSwingDamping, TEXT("6Dof joint SoftSwing damping override (if > 0)."));
FAutoConsoleVariableRef CVarChaosImmPhysJointLinearDriveStiffness(TEXT("p.Chaos.ImmPhys.Joint.LinearDriveStiffness"), ChaosImmediate_Joint_LinearDriveStiffness, TEXT("6Dof joint drive stiffness override (if > 0)."));
FAutoConsoleVariableRef CVarChaosImmPhysJointLinearDriveDamping(TEXT("p.Chaos.ImmPhys.Joint.LinearDriveDamping"), ChaosImmediate_Joint_LinearDriveDamping, TEXT("6Dof joint drive damping override (if > 0)."));
FAutoConsoleVariableRef CVarChaosImmPhysJointAngularDriveStiffness(TEXT("p.Chaos.ImmPhys.Joint.AngularDriveStiffness"), ChaosImmediate_Joint_AngularDriveStiffness, TEXT("6Dof joint drive stiffness override (if > 0)."));
#Loc: <Workspace>/Engine/Source/Runtime/Engine/Private/PhysicsEngine/ImmediatePhysics/ImmediatePhysicsChaos/ImmediatePhysicsSimulation_Chaos.cpp:887
Scope (from outer to inner):
file
namespace ImmediatePhysics_Chaos
function void FSimulation::Simulate
Source code excerpt:
JointsSettings.ShockPropagationOverride = ChaosImmediate_Joint_ShockPropagation;
JointsSettings.SoftLinearStiffnessOverride = ChaosImmediate_Joint_SoftLinearStiffness;
JointsSettings.SoftTwistStiffnessOverride = ChaosImmediate_Joint_SoftTwistStiffness;
JointsSettings.SoftTwistDampingOverride = ChaosImmediate_Joint_SoftTwistDamping;
JointsSettings.SoftSwingStiffnessOverride = ChaosImmediate_Joint_SoftSwingStiffness;
JointsSettings.SoftSwingDampingOverride = ChaosImmediate_Joint_SoftSwingDamping;
JointsSettings.LinearDriveStiffnessOverride = ChaosImmediate_Joint_LinearDriveStiffness;
JointsSettings.LinearDriveDampingOverride = ChaosImmediate_Joint_LinearDriveDamping;
JointsSettings.AngularDriveStiffnessOverride = ChaosImmediate_Joint_AngularDriveStiffness;