366 lines
15 KiB
C++
366 lines
15 KiB
C++
// Redistribution and use in source and binary forms, with or without
|
|
// modification, are permitted provided that the following conditions
|
|
// are met:
|
|
// * Redistributions of source code must retain the above copyright
|
|
// notice, this list of conditions and the following disclaimer.
|
|
// * Redistributions in binary form must reproduce the above copyright
|
|
// notice, this list of conditions and the following disclaimer in the
|
|
// documentation and/or other materials provided with the distribution.
|
|
// * Neither the name of NVIDIA CORPORATION nor the names of its
|
|
// contributors may be used to endorse or promote products derived
|
|
// from this software without specific prior written permission.
|
|
//
|
|
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS ''AS IS'' AND ANY
|
|
// EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
|
|
// PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
|
|
// CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
|
|
// EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
|
|
// PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
|
|
// PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
|
|
// OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
|
|
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
|
|
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
|
|
//
|
|
// Copyright (c) 2008-2023 NVIDIA Corporation. All rights reserved.
|
|
// Copyright (c) 2004-2008 AGEIA Technologies, Inc. All rights reserved.
|
|
// Copyright (c) 2001-2004 NovodeX AG. All rights reserved.
|
|
|
|
#ifndef PX_MASS_PROPERTIES_H
|
|
#define PX_MASS_PROPERTIES_H
|
|
/** \addtogroup extensions
|
|
@{
|
|
*/
|
|
|
|
#include "PxPhysXConfig.h"
|
|
#include "foundation/PxMath.h"
|
|
#include "foundation/PxMathUtils.h"
|
|
#include "foundation/PxVec3.h"
|
|
#include "foundation/PxMat33.h"
|
|
#include "foundation/PxQuat.h"
|
|
#include "foundation/PxTransform.h"
|
|
#include "geometry/PxGeometry.h"
|
|
#include "geometry/PxBoxGeometry.h"
|
|
#include "geometry/PxSphereGeometry.h"
|
|
#include "geometry/PxCapsuleGeometry.h"
|
|
#include "geometry/PxConvexMeshGeometry.h"
|
|
#include "geometry/PxConvexMesh.h"
|
|
#include "geometry/PxCustomGeometry.h"
|
|
#include "geometry/PxTriangleMeshGeometry.h"
|
|
#include "geometry/PxTriangleMesh.h"
|
|
|
|
#if !PX_DOXYGEN
|
|
namespace physx
|
|
{
|
|
#endif
|
|
|
|
/**
|
|
\brief Utility class to compute and manipulate mass and inertia tensor properties.
|
|
|
|
In most cases #PxRigidBodyExt::updateMassAndInertia(), #PxRigidBodyExt::setMassAndUpdateInertia() should be enough to
|
|
setup the mass properties of a rigid body. This utility class targets users that need to customize the mass properties
|
|
computation.
|
|
*/
|
|
class PxMassProperties
|
|
{
|
|
public:
|
|
/**
|
|
\brief Default constructor.
|
|
*/
|
|
PX_FORCE_INLINE PxMassProperties() : inertiaTensor(PxIdentity), centerOfMass(0.0f), mass(1.0f) {}
|
|
|
|
/**
|
|
\brief Construct from individual elements.
|
|
*/
|
|
PX_FORCE_INLINE PxMassProperties(const PxReal m, const PxMat33& inertiaT, const PxVec3& com) : inertiaTensor(inertiaT), centerOfMass(com), mass(m) {}
|
|
|
|
/**
|
|
\brief Compute mass properties based on a provided geometry structure.
|
|
|
|
This constructor assumes the geometry has a density of 1. Mass and inertia tensor scale linearly with density.
|
|
|
|
\param[in] geometry The geometry to compute the mass properties for. Supported geometry types are: sphere, box, capsule and convex mesh.
|
|
*/
|
|
PxMassProperties(const PxGeometry& geometry)
|
|
{
|
|
switch (geometry.getType())
|
|
{
|
|
case PxGeometryType::eSPHERE:
|
|
{
|
|
const PxSphereGeometry& s = static_cast<const PxSphereGeometry&>(geometry);
|
|
mass = (4.0f / 3.0f) * PxPi * s.radius * s.radius * s.radius;
|
|
inertiaTensor = PxMat33::createDiagonal(PxVec3(2.0f / 5.0f * mass * s.radius * s.radius));
|
|
centerOfMass = PxVec3(0.0f);
|
|
}
|
|
break;
|
|
|
|
case PxGeometryType::eBOX:
|
|
{
|
|
const PxBoxGeometry& b = static_cast<const PxBoxGeometry&>(geometry);
|
|
mass = b.halfExtents.x * b.halfExtents.y * b.halfExtents.z * 8.0f;
|
|
PxVec3 d2 = b.halfExtents.multiply(b.halfExtents);
|
|
inertiaTensor = PxMat33::createDiagonal(PxVec3(d2.y + d2.z, d2.x + d2.z, d2.x + d2.y)) * (mass * 1.0f / 3.0f);
|
|
centerOfMass = PxVec3(0.0f);
|
|
}
|
|
break;
|
|
|
|
case PxGeometryType::eCAPSULE:
|
|
{
|
|
const PxCapsuleGeometry& c = static_cast<const PxCapsuleGeometry&>(geometry);
|
|
PxReal r = c.radius, h = c.halfHeight;
|
|
mass = ((4.0f / 3.0f) * r + 2 * c.halfHeight) * PxPi * r * r;
|
|
|
|
PxReal a = r*r*r * (8.0f / 15.0f) + h*r*r * (3.0f / 2.0f) + h*h*r * (4.0f / 3.0f) + h*h*h * (2.0f / 3.0f);
|
|
PxReal b = r*r*r * (8.0f / 15.0f) + h*r*r;
|
|
inertiaTensor = PxMat33::createDiagonal(PxVec3(b, a, a) * PxPi * r * r);
|
|
centerOfMass = PxVec3(0.0f);
|
|
}
|
|
break;
|
|
|
|
case PxGeometryType::eCONVEXMESH:
|
|
{
|
|
const PxConvexMeshGeometry& c = static_cast<const PxConvexMeshGeometry&>(geometry);
|
|
PxVec3 unscaledCoM;
|
|
PxMat33 unscaledInertiaTensorNonCOM; // inertia tensor of convex mesh in mesh local space
|
|
PxMat33 unscaledInertiaTensorCOM;
|
|
PxReal unscaledMass;
|
|
c.convexMesh->getMassInformation(unscaledMass, unscaledInertiaTensorNonCOM, unscaledCoM);
|
|
|
|
// inertia tensor relative to center of mass
|
|
unscaledInertiaTensorCOM[0][0] = unscaledInertiaTensorNonCOM[0][0] - unscaledMass*PxReal((unscaledCoM.y*unscaledCoM.y+unscaledCoM.z*unscaledCoM.z));
|
|
unscaledInertiaTensorCOM[1][1] = unscaledInertiaTensorNonCOM[1][1] - unscaledMass*PxReal((unscaledCoM.z*unscaledCoM.z+unscaledCoM.x*unscaledCoM.x));
|
|
unscaledInertiaTensorCOM[2][2] = unscaledInertiaTensorNonCOM[2][2] - unscaledMass*PxReal((unscaledCoM.x*unscaledCoM.x+unscaledCoM.y*unscaledCoM.y));
|
|
unscaledInertiaTensorCOM[0][1] = unscaledInertiaTensorCOM[1][0] = (unscaledInertiaTensorNonCOM[0][1] + unscaledMass*PxReal(unscaledCoM.x*unscaledCoM.y));
|
|
unscaledInertiaTensorCOM[1][2] = unscaledInertiaTensorCOM[2][1] = (unscaledInertiaTensorNonCOM[1][2] + unscaledMass*PxReal(unscaledCoM.y*unscaledCoM.z));
|
|
unscaledInertiaTensorCOM[0][2] = unscaledInertiaTensorCOM[2][0] = (unscaledInertiaTensorNonCOM[0][2] + unscaledMass*PxReal(unscaledCoM.z*unscaledCoM.x));
|
|
|
|
const PxMeshScale& s = c.scale;
|
|
mass = unscaledMass * s.scale.x * s.scale.y * s.scale.z;
|
|
centerOfMass = s.transform(unscaledCoM);
|
|
inertiaTensor = scaleInertia(unscaledInertiaTensorCOM, s.rotation, s.scale);
|
|
}
|
|
break;
|
|
|
|
case PxGeometryType::eCUSTOM:
|
|
{
|
|
*this = PxMassProperties();
|
|
static_cast<const PxCustomGeometry&>(geometry).callbacks->computeMassProperties(geometry, *this);
|
|
}
|
|
break;
|
|
|
|
case PxGeometryType::eTRIANGLEMESH:
|
|
{
|
|
const PxTriangleMeshGeometry& g = static_cast<const PxTriangleMeshGeometry&>(geometry);
|
|
|
|
PxVec3 unscaledCoM;
|
|
PxMat33 unscaledInertiaTensorNonCOM; // inertia tensor of convex mesh in mesh local space
|
|
PxMat33 unscaledInertiaTensorCOM;
|
|
PxReal unscaledMass;
|
|
g.triangleMesh->getMassInformation(unscaledMass, unscaledInertiaTensorNonCOM, unscaledCoM);
|
|
|
|
// inertia tensor relative to center of mass
|
|
unscaledInertiaTensorCOM[0][0] = unscaledInertiaTensorNonCOM[0][0] - unscaledMass * PxReal((unscaledCoM.y*unscaledCoM.y + unscaledCoM.z*unscaledCoM.z));
|
|
unscaledInertiaTensorCOM[1][1] = unscaledInertiaTensorNonCOM[1][1] - unscaledMass * PxReal((unscaledCoM.z*unscaledCoM.z + unscaledCoM.x*unscaledCoM.x));
|
|
unscaledInertiaTensorCOM[2][2] = unscaledInertiaTensorNonCOM[2][2] - unscaledMass * PxReal((unscaledCoM.x*unscaledCoM.x + unscaledCoM.y*unscaledCoM.y));
|
|
unscaledInertiaTensorCOM[0][1] = unscaledInertiaTensorCOM[1][0] = (unscaledInertiaTensorNonCOM[0][1] + unscaledMass * PxReal(unscaledCoM.x*unscaledCoM.y));
|
|
unscaledInertiaTensorCOM[1][2] = unscaledInertiaTensorCOM[2][1] = (unscaledInertiaTensorNonCOM[1][2] + unscaledMass * PxReal(unscaledCoM.y*unscaledCoM.z));
|
|
unscaledInertiaTensorCOM[0][2] = unscaledInertiaTensorCOM[2][0] = (unscaledInertiaTensorNonCOM[0][2] + unscaledMass * PxReal(unscaledCoM.z*unscaledCoM.x));
|
|
|
|
const PxMeshScale& s = g.scale;
|
|
mass = unscaledMass * s.scale.x * s.scale.y * s.scale.z;
|
|
centerOfMass = s.transform(unscaledCoM);
|
|
inertiaTensor = scaleInertia(unscaledInertiaTensorCOM, s.rotation, s.scale);
|
|
}
|
|
break;
|
|
|
|
default:
|
|
{
|
|
*this = PxMassProperties();
|
|
}
|
|
}
|
|
|
|
PX_ASSERT(inertiaTensor.column0.isFinite() && inertiaTensor.column1.isFinite() && inertiaTensor.column2.isFinite());
|
|
PX_ASSERT(centerOfMass.isFinite());
|
|
PX_ASSERT(PxIsFinite(mass));
|
|
}
|
|
|
|
/**
|
|
\brief Scale mass properties.
|
|
|
|
\param[in] scale The linear scaling factor to apply to the mass properties.
|
|
\return The scaled mass properties.
|
|
*/
|
|
PX_FORCE_INLINE PxMassProperties operator*(const PxReal scale) const
|
|
{
|
|
PX_ASSERT(PxIsFinite(scale));
|
|
|
|
return PxMassProperties(mass * scale, inertiaTensor * scale, centerOfMass);
|
|
}
|
|
|
|
/**
|
|
\brief Translate the center of mass by a given vector and adjust the inertia tensor accordingly.
|
|
|
|
\param[in] t The translation vector for the center of mass.
|
|
*/
|
|
PX_FORCE_INLINE void translate(const PxVec3& t)
|
|
{
|
|
PX_ASSERT(t.isFinite());
|
|
|
|
inertiaTensor = translateInertia(inertiaTensor, mass, t);
|
|
centerOfMass += t;
|
|
|
|
PX_ASSERT(inertiaTensor.column0.isFinite() && inertiaTensor.column1.isFinite() && inertiaTensor.column2.isFinite());
|
|
PX_ASSERT(centerOfMass.isFinite());
|
|
}
|
|
|
|
/**
|
|
\brief Get the entries of the diagonalized inertia tensor and the corresponding reference rotation.
|
|
|
|
\param[in] inertia The inertia tensor to diagonalize.
|
|
\param[out] massFrame The frame the diagonalized tensor refers to.
|
|
\return The entries of the diagonalized inertia tensor.
|
|
*/
|
|
PX_FORCE_INLINE static PxVec3 getMassSpaceInertia(const PxMat33& inertia, PxQuat& massFrame)
|
|
{
|
|
PX_ASSERT(inertia.column0.isFinite() && inertia.column1.isFinite() && inertia.column2.isFinite());
|
|
|
|
PxVec3 diagT = PxDiagonalize(inertia, massFrame);
|
|
PX_ASSERT(diagT.isFinite());
|
|
PX_ASSERT(massFrame.isFinite());
|
|
return diagT;
|
|
}
|
|
|
|
/**
|
|
\brief Translate an inertia tensor using the parallel axis theorem
|
|
|
|
\param[in] inertia The inertia tensor to translate.
|
|
\param[in] mass The mass of the object.
|
|
\param[in] t The relative frame to translate the inertia tensor to.
|
|
\return The translated inertia tensor.
|
|
*/
|
|
PX_FORCE_INLINE static PxMat33 translateInertia(const PxMat33& inertia, const PxReal mass, const PxVec3& t)
|
|
{
|
|
PX_ASSERT(inertia.column0.isFinite() && inertia.column1.isFinite() && inertia.column2.isFinite());
|
|
PX_ASSERT(PxIsFinite(mass));
|
|
PX_ASSERT(t.isFinite());
|
|
|
|
PxMat33 s( PxVec3(0,t.z,-t.y),
|
|
PxVec3(-t.z,0,t.x),
|
|
PxVec3(t.y,-t.x,0) );
|
|
|
|
PxMat33 translatedIT = s.getTranspose() * s * mass + inertia;
|
|
PX_ASSERT(translatedIT.column0.isFinite() && translatedIT.column1.isFinite() && translatedIT.column2.isFinite());
|
|
return translatedIT;
|
|
}
|
|
|
|
/**
|
|
\brief Rotate an inertia tensor around the center of mass
|
|
|
|
\param[in] inertia The inertia tensor to rotate.
|
|
\param[in] q The rotation from the new to the old coordinate frame, i.e. q.rotate(v) transforms
|
|
the coordinates of vector v from the old to the new coordinate frame.
|
|
\return The rotated inertia tensor.
|
|
*/
|
|
PX_FORCE_INLINE static PxMat33 rotateInertia(const PxMat33& inertia, const PxQuat& q)
|
|
{
|
|
PX_ASSERT(inertia.column0.isFinite() && inertia.column1.isFinite() && inertia.column2.isFinite());
|
|
PX_ASSERT(q.isUnit());
|
|
|
|
PxMat33 m(q);
|
|
PxMat33 rotatedIT = m * inertia * m.getTranspose();
|
|
PX_ASSERT(rotatedIT.column0.isFinite() && rotatedIT.column1.isFinite() && rotatedIT.column2.isFinite());
|
|
return rotatedIT;
|
|
}
|
|
|
|
/**
|
|
\brief Non-uniform scaling of the inertia tensor
|
|
|
|
\param[in] inertia The inertia tensor to scale.
|
|
\param[in] scaleRotation The rotation from the scaling frame to the frame that inertia is expressed in.
|
|
I.e. scaleRotation.rotate(v) transforms the coordinates of vertex v from inertia's frame to the scaling-axes frame.
|
|
\param[in] scale The scaling factor for each axis (relative to the frame specified with scaleRotation).
|
|
\return The scaled inertia tensor.
|
|
*/
|
|
static PxMat33 scaleInertia(const PxMat33& inertia, const PxQuat& scaleRotation, const PxVec3& scale)
|
|
{
|
|
PX_ASSERT(inertia.column0.isFinite() && inertia.column1.isFinite() && inertia.column2.isFinite());
|
|
PX_ASSERT(scaleRotation.isUnit());
|
|
PX_ASSERT(scale.isFinite());
|
|
|
|
PxMat33 localInertiaT = rotateInertia(inertia, scaleRotation); // rotate inertia into scaling frame
|
|
PxVec3 diagonal(localInertiaT[0][0], localInertiaT[1][1], localInertiaT[2][2]);
|
|
|
|
PxVec3 xyz2 = PxVec3(diagonal.dot(PxVec3(0.5f))) - diagonal; // original x^2, y^2, z^2
|
|
PxVec3 scaledxyz2 = xyz2.multiply(scale).multiply(scale);
|
|
|
|
PxReal xx = scaledxyz2.y + scaledxyz2.z,
|
|
yy = scaledxyz2.z + scaledxyz2.x,
|
|
zz = scaledxyz2.x + scaledxyz2.y;
|
|
|
|
PxReal xy = localInertiaT[0][1] * scale.x * scale.y,
|
|
xz = localInertiaT[0][2] * scale.x * scale.z,
|
|
yz = localInertiaT[1][2] * scale.y * scale.z;
|
|
|
|
PxMat33 scaledInertia( PxVec3(xx, xy, xz),
|
|
PxVec3(xy, yy, yz),
|
|
PxVec3(xz, yz, zz));
|
|
|
|
PxMat33 scaledIT = rotateInertia(scaledInertia * (scale.x * scale.y * scale.z), scaleRotation.getConjugate());
|
|
PX_ASSERT(scaledIT.column0.isFinite() && scaledIT.column1.isFinite() && scaledIT.column2.isFinite());
|
|
return scaledIT;
|
|
}
|
|
|
|
/**
|
|
\brief Sum up individual mass properties.
|
|
|
|
\param[in] props Array of mass properties to sum up.
|
|
\param[in] transforms Reference transforms for each mass properties entry.
|
|
\param[in] count The number of mass properties to sum up.
|
|
\return The summed up mass properties.
|
|
*/
|
|
static PxMassProperties sum(const PxMassProperties* props, const PxTransform* transforms, const PxU32 count)
|
|
{
|
|
PxReal combinedMass = 0.0f;
|
|
PxVec3 combinedCoM(0.0f);
|
|
PxMat33 combinedInertiaT = PxMat33(PxZero);
|
|
|
|
for(PxU32 i = 0; i < count; i++)
|
|
{
|
|
PX_ASSERT(props[i].inertiaTensor.column0.isFinite() && props[i].inertiaTensor.column1.isFinite() && props[i].inertiaTensor.column2.isFinite());
|
|
PX_ASSERT(props[i].centerOfMass.isFinite());
|
|
PX_ASSERT(PxIsFinite(props[i].mass));
|
|
|
|
combinedMass += props[i].mass;
|
|
const PxVec3 comTm = transforms[i].transform(props[i].centerOfMass);
|
|
combinedCoM += comTm * props[i].mass;
|
|
}
|
|
|
|
if(combinedMass > 0.f)
|
|
combinedCoM /= combinedMass;
|
|
|
|
for(PxU32 i = 0; i < count; i++)
|
|
{
|
|
const PxVec3 comTm = transforms[i].transform(props[i].centerOfMass);
|
|
combinedInertiaT += translateInertia(rotateInertia(props[i].inertiaTensor, transforms[i].q), props[i].mass, combinedCoM - comTm);
|
|
}
|
|
|
|
PX_ASSERT(combinedInertiaT.column0.isFinite() && combinedInertiaT.column1.isFinite() && combinedInertiaT.column2.isFinite());
|
|
PX_ASSERT(combinedCoM.isFinite());
|
|
PX_ASSERT(PxIsFinite(combinedMass));
|
|
|
|
return PxMassProperties(combinedMass, combinedInertiaT, combinedCoM);
|
|
}
|
|
|
|
|
|
PxMat33 inertiaTensor; //!< The inertia tensor of the object.
|
|
PxVec3 centerOfMass; //!< The center of mass of the object.
|
|
PxReal mass; //!< The mass of the object.
|
|
};
|
|
|
|
#if !PX_DOXYGEN
|
|
} // namespace physx
|
|
#endif
|
|
|
|
/** @} */
|
|
#endif
|