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// Copyright (c) 2001-2004 NovodeX AG. All rights reserved.
// Copyright (c) 2004-2008 AGEIA Technologies, Inc. All rights reserved.
// SPDX-FileCopyrightText: Copyright (c) 2008-2026 NVIDIA CORPORATION & AFFILIATES. All rights reserved.
// SPDX-License-Identifier: Apache-2.0
#ifndef PX_JOINT_LIMIT_H
#define PX_JOINT_LIMIT_H
#include "foundation/PxMath.h"
#include "common/PxTolerancesScale.h"
#include "extensions/PxJoint.h"
#include "PxPhysXConfig.h"
#if !PX_DOXYGEN
namespace physx
{
#endif
/**
\brief Describes the parameters for a joint limit.
Limits are enabled or disabled by setting flags or other configuration parameters joints, see the
documentation for specific joint types for details.
*/
class PxJointLimitParameters
{
public:
/**
\brief Controls the amount of bounce when the joint hits a limit.
A restitution value of 1.0 causes the joint to bounce back with the velocity which it hit the limit.
A value of zero causes the joint to stop dead.
In situations where the joint has many locked DOFs (e.g. 5) the restitution may not be applied
correctly. This is due to a limitation in the solver which causes the restitution velocity to become zero
as the solver enforces constraints on the other DOFs.
This limitation applies to both angular and linear limits, however it is generally most apparent with limited
angular DOFs. Disabling joint projection and increasing the solver iteration count may improve this behavior
to some extent.
Also, combining soft joint limits with joint drives driving against those limits may affect stability.
<b>Range:</b> [0,1]<br>
<b>Default:</b> 0.0
*/
PxReal restitution;
/**
determines the minimum impact velocity which will cause the joint to bounce
*/
PxReal bounceThreshold;
/**
\brief if greater than zero, the limit is soft, i.e. a spring pulls the joint back to the limit
<b>Range:</b> [0, PX_MAX_F32)<br>
<b>Default:</b> 0.0
*/
PxReal stiffness;
/**
\brief if spring is greater than zero, this is the damping of the limit spring
<b>Range:</b> [0, PX_MAX_F32)<br>
<b>Default:</b> 0.0
*/
PxReal damping;
PxJointLimitParameters() :
restitution (0.0f),
bounceThreshold (0.0f),
stiffness (0.0f),
damping (0.0f)
{
}
PxJointLimitParameters(const PxJointLimitParameters& p) :
restitution (p.restitution),
bounceThreshold (p.bounceThreshold),
stiffness (p.stiffness),
damping (p.damping)
{
}
/**
\brief Returns true if the current settings are valid.
\return true if the current settings are valid
*/
PX_INLINE bool isValid() const
{
return PxIsFinite(restitution) && restitution >= 0 && restitution <= 1 &&
PxIsFinite(stiffness) && stiffness >= 0 &&
PxIsFinite(damping) && damping >= 0 &&
PxIsFinite(bounceThreshold) && bounceThreshold >= 0;
}
PX_INLINE bool isSoft() const
{
return damping>0 || stiffness>0;
}
protected:
~PxJointLimitParameters() {}
};
/**
\brief Describes a one-sided linear limit.
*/
class PxJointLinearLimit : public PxJointLimitParameters
{
public:
/**
\brief the extent of the limit.
<b>Range:</b> (0, PX_MAX_F32) <br>
<b>Default:</b> PX_MAX_F32
*/
PxReal value;
/**
\brief construct a linear hard limit
\param[in] extent The extent of the limit
\see PxJointLimitParameters
*/
PxJointLinearLimit(PxReal extent) : value(extent)
{
}
/**
\brief construct a linear soft limit
\param[in] extent the extent of the limit
\param[in] spring the stiffness and damping parameters for the limit spring
\see PxJointLimitParameters
*/
PxJointLinearLimit(PxReal extent, const PxSpring& spring) : value(extent)
{
stiffness = spring.stiffness;
damping = spring.damping;
}
/**
\brief Returns true if the limit is valid
\return true if the current settings are valid
*/
PX_INLINE bool isValid() const
{
return PxJointLimitParameters::isValid() &&
PxIsFinite(value) &&
value > 0.0f;
}
};
/**
\brief Describes a two-sided limit.
*/
class PxJointLinearLimitPair : public PxJointLimitParameters
{
public:
/**
\brief the range of the limit. The upper limit must be no lower than the
lower limit, and if they are equal the limited degree of freedom will be treated as locked.
<b>Range:</b> See the joint on which the limit is used for details<br>
<b>Default:</b> lower = -PX_MAX_F32/3, upper = PX_MAX_F32/3
*/
PxReal upper, lower;
/**
\brief Construct a linear hard limit pair. The lower distance value must be less than the upper distance value.
\param[in] scale A PxTolerancesScale struct. Should be the same as used when creating the PxPhysics object.
\param[in] lowerLimit The lower distance of the limit
\param[in] upperLimit The upper distance of the limit
\see PxJointLimitParameters PxTolerancesScale
*/
PxJointLinearLimitPair(const PxTolerancesScale& scale, PxReal lowerLimit = -PX_MAX_F32/3.0f, PxReal upperLimit = PX_MAX_F32/3.0f) :
upper(upperLimit),
lower(lowerLimit)
{
bounceThreshold = 2.0f*scale.length;
}
/**
\brief construct a linear soft limit pair
\param[in] lowerLimit The lower distance of the limit
\param[in] upperLimit The upper distance of the limit
\param[in] spring The stiffness and damping parameters of the limit spring
\see PxJointLimitParameters
*/
PxJointLinearLimitPair(PxReal lowerLimit, PxReal upperLimit, const PxSpring& spring) :
upper(upperLimit),
lower(lowerLimit)
{
stiffness = spring.stiffness;
damping = spring.damping;
}
/**
\brief Returns true if the limit is valid.
\return true if the current settings are valid
*/
PX_INLINE bool isValid() const
{
return PxJointLimitParameters::isValid() &&
PxIsFinite(upper) && PxIsFinite(lower) && upper >= lower &&
PxIsFinite(upper - lower);
}
};
class PxJointAngularLimitPair : public PxJointLimitParameters
{
public:
/**
\brief the range of the limit. The upper limit must be no lower than the lower limit.
<b>Unit:</b> Angular: Radians
<b>Range:</b> See the joint on which the limit is used for details<br>
<b>Default:</b> lower = -PI/2, upper = PI/2
*/
PxReal upper, lower;
/**
\brief construct an angular hard limit pair.
The lower value must be less than the upper value.
\param[in] lowerLimit The lower angle of the limit
\param[in] upperLimit The upper angle of the limit
\see PxJointLimitParameters
*/
PxJointAngularLimitPair(PxReal lowerLimit, PxReal upperLimit) :
upper(upperLimit),
lower(lowerLimit)
{
bounceThreshold = 0.5f;
}
/**
\brief construct an angular soft limit pair.
The lower value must be less than the upper value.
\param[in] lowerLimit The lower angle of the limit
\param[in] upperLimit The upper angle of the limit
\param[in] spring The stiffness and damping of the limit spring
\see PxJointLimitParameters
*/
PxJointAngularLimitPair(PxReal lowerLimit, PxReal upperLimit, const PxSpring& spring) :
upper(upperLimit),
lower(lowerLimit)
{
stiffness = spring.stiffness;
damping = spring.damping;
}
/**
\brief Returns true if the limit is valid.
\return true if the current settings are valid
*/
PX_INLINE bool isValid() const
{
return PxJointLimitParameters::isValid() &&
PxIsFinite(upper) && PxIsFinite(lower) && upper >= lower;
}
};
/**
\brief Describes an elliptical conical joint limit. Note that very small or highly elliptical limit cones may
result in jitter.
\see PxD6Joint PxSphericalJoint
*/
class PxJointLimitCone : public PxJointLimitParameters
{
public:
/**
\brief the maximum angle from the Y axis of the constraint frame.
<b>Unit:</b> Angular: Radians
<b>Range:</b> Angular: (0,PI)<br>
<b>Default:</b> PI/2
*/
PxReal yAngle;
/**
\brief the maximum angle from the Z-axis of the constraint frame.
<b>Unit:</b> Angular: Radians
<b>Range:</b> Angular: (0,PI)<br>
<b>Default:</b> PI/2
*/
PxReal zAngle;
/**
\brief Construct a cone hard limit.
\param[in] yLimitAngle The limit angle from the Y-axis of the constraint frame
\param[in] zLimitAngle The limit angle from the Z-axis of the constraint frame
\see PxJointLimitParameters
*/
PxJointLimitCone(PxReal yLimitAngle, PxReal zLimitAngle) :
yAngle(yLimitAngle),
zAngle(zLimitAngle)
{
bounceThreshold = 0.5f;
}
/**
\brief Construct a cone soft limit.
\param[in] yLimitAngle The limit angle from the Y-axis of the constraint frame
\param[in] zLimitAngle The limit angle from the Z-axis of the constraint frame
\param[in] spring The stiffness and damping of the limit spring
\see PxJointLimitParameters
*/
PxJointLimitCone(PxReal yLimitAngle, PxReal zLimitAngle, const PxSpring& spring) :
yAngle(yLimitAngle),
zAngle(zLimitAngle)
{
stiffness = spring.stiffness;
damping = spring.damping;
}
/**
\brief Returns true if the limit is valid.
\return true if the current settings are valid
*/
PX_INLINE bool isValid() const
{
return PxJointLimitParameters::isValid() &&
PxIsFinite(yAngle) && yAngle>0 && yAngle<PxPi &&
PxIsFinite(zAngle) && zAngle>0 && zAngle<PxPi;
}
};
/**
\brief Describes a pyramidal joint limit.
\see PxD6Joint
*/
class PxJointLimitPyramid : public PxJointLimitParameters
{
public:
/**
\brief the minimum angle from the Y axis of the constraint frame.
<b>Unit:</b> Angular: Radians
<b>Range:</b> Angular: (-PI,PI)<br>
<b>Default:</b> -PI/2
*/
PxReal yAngleMin;
/**
\brief the maximum angle from the Y axis of the constraint frame.
<b>Unit:</b> Angular: Radians
<b>Range:</b> Angular: (-PI,PI)<br>
<b>Default:</b> PI/2
*/
PxReal yAngleMax;
/**
\brief the minimum angle from the Z-axis of the constraint frame.
<b>Unit:</b> Angular: Radians
<b>Range:</b> Angular: (-PI,PI)<br>
<b>Default:</b> -PI/2
*/
PxReal zAngleMin;
/**
\brief the maximum angle from the Z-axis of the constraint frame.
<b>Unit:</b> Angular: Radians
<b>Range:</b> Angular: (-PI,PI)<br>
<b>Default:</b> PI/2
*/
PxReal zAngleMax;
/**
\brief Construct a pyramid hard limit.
\param[in] yLimitAngleMin The minimum limit angle from the Y-axis of the constraint frame
\param[in] yLimitAngleMax The maximum limit angle from the Y-axis of the constraint frame
\param[in] zLimitAngleMin The minimum limit angle from the Z-axis of the constraint frame
\param[in] zLimitAngleMax The maximum limit angle from the Z-axis of the constraint frame
\see PxJointLimitParameters
*/
PxJointLimitPyramid(PxReal yLimitAngleMin, PxReal yLimitAngleMax, PxReal zLimitAngleMin, PxReal zLimitAngleMax) :
yAngleMin(yLimitAngleMin),
yAngleMax(yLimitAngleMax),
zAngleMin(zLimitAngleMin),
zAngleMax(zLimitAngleMax)
{
bounceThreshold = 0.5f;
}
/**
\brief Construct a pyramid soft limit.
\param[in] yLimitAngleMin The minimum limit angle from the Y-axis of the constraint frame
\param[in] yLimitAngleMax The maximum limit angle from the Y-axis of the constraint frame
\param[in] zLimitAngleMin The minimum limit angle from the Z-axis of the constraint frame
\param[in] zLimitAngleMax The maximum limit angle from the Z-axis of the constraint frame
\param[in] spring The stiffness and damping of the limit spring
\see PxJointLimitParameters
*/
PxJointLimitPyramid(PxReal yLimitAngleMin, PxReal yLimitAngleMax, PxReal zLimitAngleMin, PxReal zLimitAngleMax, const PxSpring& spring) :
yAngleMin(yLimitAngleMin),
yAngleMax(yLimitAngleMax),
zAngleMin(zLimitAngleMin),
zAngleMax(zLimitAngleMax)
{
stiffness = spring.stiffness;
damping = spring.damping;
}
/**
\brief Returns true if the limit is valid.
\return true if the current settings are valid
*/
PX_INLINE bool isValid() const
{
return PxJointLimitParameters::isValid() &&
PxIsFinite(yAngleMin) && yAngleMin>-PxPi && yAngleMin<PxPi &&
PxIsFinite(yAngleMax) && yAngleMax>-PxPi && yAngleMax<PxPi &&
PxIsFinite(zAngleMin) && zAngleMin>-PxPi && zAngleMin<PxPi &&
PxIsFinite(zAngleMax) && zAngleMax>-PxPi && zAngleMax<PxPi &&
yAngleMax>=yAngleMin && zAngleMax>=zAngleMin;
}
};
#if !PX_DOXYGEN
} // namespace physx
#endif
#endif