godot-module-template/engine/thirdparty/jolt_physics/Jolt/Physics/Body/MotionProperties.cpp

93 lines
2.6 KiB
C++

// Jolt Physics Library (https://github.com/jrouwe/JoltPhysics)
// SPDX-FileCopyrightText: 2021 Jorrit Rouwe
// SPDX-License-Identifier: MIT
#include <Jolt/Jolt.h>
#include <Jolt/Physics/Body/MotionProperties.h>
#include <Jolt/Physics/StateRecorder.h>
JPH_NAMESPACE_BEGIN
void MotionProperties::SetMassProperties(EAllowedDOFs inAllowedDOFs, const MassProperties &inMassProperties)
{
// Store allowed DOFs
mAllowedDOFs = inAllowedDOFs;
// Decompose DOFs
uint allowed_translation_axis = uint(inAllowedDOFs) & 0b111;
uint allowed_rotation_axis = (uint(inAllowedDOFs) >> 3) & 0b111;
// Set inverse mass
if (allowed_translation_axis == 0)
{
// No translation possible
mInvMass = 0.0f;
}
else
{
JPH_ASSERT(inMassProperties.mMass > 0.0f, "Invalid mass. "
"Some shapes like MeshShape or TriangleShape cannot calculate mass automatically, "
"in this case you need to provide it by setting BodyCreationSettings::mOverrideMassProperties and mMassPropertiesOverride.");
mInvMass = 1.0f / inMassProperties.mMass;
}
if (allowed_rotation_axis == 0)
{
// No rotation possible
mInvInertiaDiagonal = Vec3::sZero();
mInertiaRotation = Quat::sIdentity();
}
else
{
// Set inverse inertia
Mat44 rotation;
Vec3 diagonal;
if (inMassProperties.DecomposePrincipalMomentsOfInertia(rotation, diagonal)
&& !diagonal.IsNearZero())
{
mInvInertiaDiagonal = diagonal.Reciprocal();
mInertiaRotation = rotation.GetQuaternion();
}
else
{
// Failed! Fall back to inertia tensor of sphere with radius 1.
mInvInertiaDiagonal = Vec3::sReplicate(2.5f * mInvMass);
mInertiaRotation = Quat::sIdentity();
}
}
JPH_ASSERT(mInvMass != 0.0f || mInvInertiaDiagonal != Vec3::sZero(), "Can't lock all axes, use a static body for this. This will crash with a division by zero later!");
}
void MotionProperties::SaveState(StateRecorder &inStream) const
{
// Only write properties that can change at runtime
inStream.Write(mLinearVelocity);
inStream.Write(mAngularVelocity);
inStream.Write(mForce);
inStream.Write(mTorque);
#ifdef JPH_DOUBLE_PRECISION
inStream.Write(mSleepTestOffset);
#endif // JPH_DOUBLE_PRECISION
inStream.Write(mSleepTestSpheres);
inStream.Write(mSleepTestTimer);
inStream.Write(mAllowSleeping);
}
void MotionProperties::RestoreState(StateRecorder &inStream)
{
inStream.Read(mLinearVelocity);
inStream.Read(mAngularVelocity);
inStream.Read(mForce);
inStream.Read(mTorque);
#ifdef JPH_DOUBLE_PRECISION
inStream.Read(mSleepTestOffset);
#endif // JPH_DOUBLE_PRECISION
inStream.Read(mSleepTestSpheres);
inStream.Read(mSleepTestTimer);
inStream.Read(mAllowSleeping);
}
JPH_NAMESPACE_END