Jolt Physics
A multi core friendly Game Physics Engine
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MotionProperties.h
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1// Jolt Physics Library (https://github.com/jrouwe/JoltPhysics)
2// SPDX-FileCopyrightText: 2021 Jorrit Rouwe
3// SPDX-License-Identifier: MIT
4
5#pragma once
6
15
17
18class StateRecorder;
19
21enum class ECanSleep
22{
23 CannotSleep = 0,
24 CanSleep = 1,
25};
26
29{
30public:
32
34 EMotionQuality GetMotionQuality() const { return mMotionQuality; }
35
37 inline EAllowedDOFs GetAllowedDOFs() const { return mAllowedDOFs; }
38
40 inline bool GetAllowSleeping() const { return mAllowSleeping; }
41
43 inline Vec3 GetLinearVelocity() const { JPH_ASSERT(BodyAccess::sCheckRights(BodyAccess::sVelocityAccess(), BodyAccess::EAccess::Read)); return mLinearVelocity; }
44
46 void SetLinearVelocity(Vec3Arg inLinearVelocity) { JPH_ASSERT(BodyAccess::sCheckRights(BodyAccess::sVelocityAccess(), BodyAccess::EAccess::ReadWrite)); JPH_ASSERT(inLinearVelocity.Length() <= mMaxLinearVelocity); mLinearVelocity = LockTranslation(inLinearVelocity); }
47
49 void SetLinearVelocityClamped(Vec3Arg inLinearVelocity) { mLinearVelocity = LockTranslation(inLinearVelocity); ClampLinearVelocity(); }
50
52 inline Vec3 GetAngularVelocity() const { JPH_ASSERT(BodyAccess::sCheckRights(BodyAccess::sVelocityAccess(), BodyAccess::EAccess::Read)); return mAngularVelocity; }
53
55 void SetAngularVelocity(Vec3Arg inAngularVelocity) { JPH_ASSERT(BodyAccess::sCheckRights(BodyAccess::sVelocityAccess(), BodyAccess::EAccess::ReadWrite)); JPH_ASSERT(inAngularVelocity.Length() <= mMaxAngularVelocity); mAngularVelocity = LockAngular(inAngularVelocity); }
56
58 void SetAngularVelocityClamped(Vec3Arg inAngularVelocity) { mAngularVelocity = LockAngular(inAngularVelocity); ClampAngularVelocity(); }
59
61 inline void MoveKinematic(Vec3Arg inDeltaPosition, QuatArg inDeltaRotation, float inDeltaTime);
62
65
67 inline float GetMaxLinearVelocity() const { return mMaxLinearVelocity; }
68 inline void SetMaxLinearVelocity(float inLinearVelocity) { JPH_ASSERT(inLinearVelocity >= 0.0f); mMaxLinearVelocity = inLinearVelocity; }
69
71 inline float GetMaxAngularVelocity() const { return mMaxAngularVelocity; }
72 inline void SetMaxAngularVelocity(float inAngularVelocity) { JPH_ASSERT(inAngularVelocity >= 0.0f); mMaxAngularVelocity = inAngularVelocity; }
74
76 inline void ClampLinearVelocity();
77 inline void ClampAngularVelocity();
78
80 inline float GetLinearDamping() const { return mLinearDamping; }
81 void SetLinearDamping(float inLinearDamping) { JPH_ASSERT(inLinearDamping >= 0.0f); mLinearDamping = inLinearDamping; }
82
84 inline float GetAngularDamping() const { return mAngularDamping; }
85 void SetAngularDamping(float inAngularDamping) { JPH_ASSERT(inAngularDamping >= 0.0f); mAngularDamping = inAngularDamping; }
86
88 inline float GetGravityFactor() const { return mGravityFactor; }
89 void SetGravityFactor(float inGravityFactor) { mGravityFactor = inGravityFactor; }
90
92 void SetMassProperties(EAllowedDOFs inAllowedDOFs, const MassProperties &inMassProperties);
93
95 inline float GetInverseMass() const { JPH_ASSERT(mCachedMotionType == EMotionType::Dynamic); return mInvMass; }
96 inline float GetInverseMassUnchecked() const { return mInvMass; }
97
102 void SetInverseMass(float inInverseMass) { mInvMass = inInverseMass; }
103
105 inline Vec3 GetInverseInertiaDiagonal() const { JPH_ASSERT(mCachedMotionType == EMotionType::Dynamic); return mInvInertiaDiagonal; }
106
108 inline Quat GetInertiaRotation() const { return mInertiaRotation; }
109
114 void SetInverseInertia(Vec3Arg inDiagonal, QuatArg inRot) { mInvInertiaDiagonal = inDiagonal; mInertiaRotation = inRot; }
115
118 void ScaleToMass(float inMass);
119
121 inline Mat44 GetLocalSpaceInverseInertia() const;
122
124 inline Mat44 GetLocalSpaceInverseInertiaUnchecked() const;
125
127 inline Mat44 GetInverseInertiaForRotation(Mat44Arg inRotation) const;
128
130 JPH_INLINE Vec3 MultiplyWorldSpaceInverseInertiaByVector(QuatArg inBodyRotation, Vec3Arg inV) const;
131
133 JPH_INLINE Vec3 GetPointVelocityCOM(Vec3Arg inPointRelativeToCOM) const { return mLinearVelocity + mAngularVelocity.Cross(inPointRelativeToCOM); }
134
135 // Get the total amount of force applied to the center of mass this time step (through Body::AddForce calls). Note that it will reset to zero after PhysicsSystem::Update.
136 JPH_INLINE Vec3 GetAccumulatedForce() const { return Vec3::sLoadFloat3Unsafe(mForce); }
137
138 // Get the total amount of torque applied to the center of mass this time step (through Body::AddForce/Body::AddTorque calls). Note that it will reset to zero after PhysicsSystem::Update.
139 JPH_INLINE Vec3 GetAccumulatedTorque() const { return Vec3::sLoadFloat3Unsafe(mTorque); }
140
141 // Reset the total accumulated force, note that this will be done automatically after every time step.
142 JPH_INLINE void ResetForce() { mForce = Float3(0, 0, 0); }
143
144 // Reset the total accumulated torque, note that this will be done automatically after every time step.
145 JPH_INLINE void ResetTorque() { mTorque = Float3(0, 0, 0); }
146
147 // Reset the current velocity and accumulated force and torque.
148 JPH_INLINE void ResetMotion()
149 {
150 JPH_ASSERT(BodyAccess::sCheckRights(BodyAccess::sVelocityAccess(), BodyAccess::EAccess::ReadWrite));
151 mLinearVelocity = mAngularVelocity = Vec3::sZero();
152 mForce = mTorque = Float3(0, 0, 0);
153 }
154
161
163 JPH_INLINE Vec3 LockTranslation(Vec3Arg inV) const
164 {
165 return Vec3::sAnd(inV, Vec3(GetLinearDOFsMask().ReinterpretAsFloat()));
166 }
167
174
176 JPH_INLINE Vec3 LockAngular(Vec3Arg inV) const
177 {
178 return Vec3::sAnd(inV, Vec3(GetAngularDOFsMask().ReinterpretAsFloat()));
179 }
180
182 void SetNumVelocityStepsOverride(uint inN) { JPH_ASSERT(inN < 256); mNumVelocityStepsOverride = uint8(inN); }
183 uint GetNumVelocityStepsOverride() const { return mNumVelocityStepsOverride; }
184
186 void SetNumPositionStepsOverride(uint inN) { JPH_ASSERT(inN < 256); mNumPositionStepsOverride = uint8(inN); }
187 uint GetNumPositionStepsOverride() const { return mNumPositionStepsOverride; }
188
189#ifdef JPH_TRACK_SIMULATION_STATS
191 struct SimulationStats
192 {
193 void Reset() { mBroadPhaseTicks = 0; mNarrowPhaseTicks.store(0, memory_order_relaxed); mVelocityConstraintTicks = 0; mPositionConstraintTicks = 0; mUpdateBoundsTicks = 0; mCCDTicks.store(0, memory_order_relaxed); mNumContactConstraints.store(0, memory_order_relaxed); mNumVelocitySteps = 0; mNumPositionSteps = 0; mIsLargeIsland = false; }
194
195 uint64 mBroadPhaseTicks = 0;
196 atomic<uint64> mNarrowPhaseTicks = 0;
197 uint64 mVelocityConstraintTicks = 0;
198 uint64 mPositionConstraintTicks = 0;
199 uint64 mUpdateBoundsTicks = 0;
200 atomic<uint64> mCCDTicks = 0;
201 atomic<uint32> mNumContactConstraints = 0;
202 uint8 mNumVelocitySteps = 0;
203 uint8 mNumPositionSteps = 0;
204 bool mIsLargeIsland = false;
205 };
206
207 const SimulationStats & GetSimulationStats() const { return mSimulationStats; }
208 SimulationStats & GetSimulationStats() { return mSimulationStats; }
209#endif // JPH_TRACK_SIMULATION_STATS
210
212 // FUNCTIONS BELOW THIS LINE ARE FOR INTERNAL USE ONLY
214
217 inline void AddLinearVelocityStep(Vec3Arg inLinearVelocityChange) { JPH_DET_LOG("AddLinearVelocityStep: " << inLinearVelocityChange); JPH_ASSERT(BodyAccess::sCheckRights(BodyAccess::sVelocityAccess(), BodyAccess::EAccess::ReadWrite)); mLinearVelocity = LockTranslation(mLinearVelocity + inLinearVelocityChange); JPH_ASSERT(!mLinearVelocity.IsNaN()); }
218 inline void SubLinearVelocityStep(Vec3Arg inLinearVelocityChange) { JPH_DET_LOG("SubLinearVelocityStep: " << inLinearVelocityChange); JPH_ASSERT(BodyAccess::sCheckRights(BodyAccess::sVelocityAccess(), BodyAccess::EAccess::ReadWrite)); mLinearVelocity = LockTranslation(mLinearVelocity - inLinearVelocityChange); JPH_ASSERT(!mLinearVelocity.IsNaN()); }
219 inline void ApplyLinearVelocityStep(Vec3Arg inLinearVelocity) { JPH_DET_LOG("ApplyLinearVelocityStep: " << inLinearVelocity); JPH_ASSERT(BodyAccess::sCheckRights(BodyAccess::sVelocityAccess(), BodyAccess::EAccess::ReadWrite)); JPH_ASSERT(!inLinearVelocity.IsNaN()); mLinearVelocity = LockTranslation(inLinearVelocity); }
220 inline void AddAngularVelocityStep(Vec3Arg inAngularVelocityChange) { JPH_DET_LOG("AddAngularVelocityStep: " << inAngularVelocityChange); JPH_ASSERT(BodyAccess::sCheckRights(BodyAccess::sVelocityAccess(), BodyAccess::EAccess::ReadWrite)); mAngularVelocity += inAngularVelocityChange; JPH_ASSERT(!mAngularVelocity.IsNaN()); }
221 inline void SubAngularVelocityStep(Vec3Arg inAngularVelocityChange) { JPH_DET_LOG("SubAngularVelocityStep: " << inAngularVelocityChange); JPH_ASSERT(BodyAccess::sCheckRights(BodyAccess::sVelocityAccess(), BodyAccess::EAccess::ReadWrite)); mAngularVelocity -= inAngularVelocityChange; JPH_ASSERT(!mAngularVelocity.IsNaN()); }
222 inline void ApplyAngularVelocityStep(Vec3Arg inAngularVelocity) { JPH_DET_LOG("ApplyAngularVelocityStep: " << inAngularVelocity); JPH_ASSERT(BodyAccess::sCheckRights(BodyAccess::sVelocityAccess(), BodyAccess::EAccess::ReadWrite)); JPH_ASSERT(!inAngularVelocity.IsNaN()); mAngularVelocity = inAngularVelocity; }
224
226 inline void ApplyGyroscopicForceInternal(QuatArg inBodyRotation, float inDeltaTime);
227
229 inline void ApplyForceTorqueAndDragInternal(QuatArg inBodyRotation, Vec3Arg inGravity, float inDeltaTime);
230
232 uint32 GetIslandIndexInternal() const { return mIslandIndex; }
233 void SetIslandIndexInternal(uint32 inIndex) { mIslandIndex = inIndex; }
234
236 uint32 GetIndexInActiveBodiesInternal() const { return mIndexInActiveBodies; }
237
238#ifdef JPH_DOUBLE_PRECISION
239 inline DVec3 GetSleepTestOffset() const { return DVec3::sLoadDouble3Unsafe(mSleepTestOffset); }
240#endif // JPH_DOUBLE_PRECISION
241
243 inline void ResetSleepTestSpheres(const RVec3 *inPoints);
244
246 inline void ResetSleepTestTimer() { mSleepTestTimer = 0.0f; }
247
249 inline ECanSleep AccumulateSleepTime(float inDeltaTime, float inTimeBeforeSleep);
250
252 void SaveState(StateRecorder &inStream) const;
253
255 void RestoreState(StateRecorder &inStream);
256
257 static constexpr uint32 cInactiveIndex = uint32(-1);
258
259private:
260 friend class BodyManager;
261 friend class Body;
262
263 // 1st cache line
264 // 16 byte aligned
265 Vec3 mLinearVelocity { Vec3::sZero() };
266 Vec3 mAngularVelocity { Vec3::sZero() };
267 Vec3 mInvInertiaDiagonal;
268 Quat mInertiaRotation;
269
270 // 2nd cache line
271 // 4 byte aligned
272 Float3 mForce { 0, 0, 0 };
273 Float3 mTorque { 0, 0, 0 };
274 float mInvMass;
275 float mLinearDamping;
276 float mAngularDamping;
277 float mMaxLinearVelocity;
278 float mMaxAngularVelocity;
279 float mGravityFactor;
280 uint32 mIndexInActiveBodies = cInactiveIndex;
281 uint32 mIslandIndex = cInactiveIndex;
282
283 // 1 byte aligned
284 EMotionQuality mMotionQuality;
285 bool mAllowSleeping;
286 EAllowedDOFs mAllowedDOFs = EAllowedDOFs::All;
287 uint8 mNumVelocityStepsOverride = 0;
288 uint8 mNumPositionStepsOverride = 0;
289
290 // 3rd cache line (least frequently used)
291 // 4 byte aligned (or 8 byte if running in double precision)
292#ifdef JPH_DOUBLE_PRECISION
293 Double3 mSleepTestOffset;
294#endif // JPH_DOUBLE_PRECISION
295 Sphere mSleepTestSpheres[3];
296 float mSleepTestTimer;
297
298#ifdef JPH_ENABLE_ASSERTS
299 EBodyType mCachedBodyType;
300 EMotionType mCachedMotionType;
301#endif
302
303#ifdef JPH_TRACK_SIMULATION_STATS
304 SimulationStats mSimulationStats;
305#endif // JPH_TRACK_SIMULATION_STATS
306};
307
309
310#include "MotionProperties.inl"
EAllowedDOFs
Enum used in BodyCreationSettings and MotionProperties to indicate which degrees of freedom a body ha...
Definition AllowedDOFs.h:11
@ RotationX
Body can rotate around world space X axis.
@ TranslationY
Body can move in world space Y axis.
@ RotationY
Body can rotate around world space Y axis.
@ TranslationZ
Body can move in world space Z axis.
@ All
All degrees of freedom are allowed.
@ TranslationX
Body can move in world space X axis.
@ RotationZ
Body can rotate around world space Z axis.
EBodyType
Type of body.
Definition BodyType.h:11
std::uint8_t uint8
Definition Core.h:506
#define JPH_EXPORT
Definition Core.h:278
std::uint64_t uint64
Definition Core.h:510
unsigned int uint
Definition Core.h:505
#define JPH_NAMESPACE_END
Definition Core.h:428
std::uint32_t uint32
Definition Core.h:508
#define JPH_NAMESPACE_BEGIN
Definition Core.h:422
#define JPH_DET_LOG(...)
By default we log nothing.
Definition DeterminismLog.h:155
#define JPH_ASSERT(...)
Definition IssueReporting.h:33
#define JPH_OVERRIDE_NEW_DELETE
Macro to override the new and delete functions.
Definition Memory.h:50
ECanSleep
Enum that determines if an object can go to sleep.
Definition MotionProperties.h:22
@ CanSleep
Object can go to sleep.
@ CannotSleep
Object cannot go to sleep.
EMotionQuality
Motion quality, or how well it detects collisions when it has a high velocity.
Definition MotionQuality.h:11
EMotionType
Motion type of a physics body.
Definition MotionType.h:11
@ Dynamic
Responds to forces as a normal physics object.
Definition Body.h:39
Definition BodyManager.h:47
Definition DVec3.h:14
static JPH_INLINE DVec3 sLoadDouble3Unsafe(const Double3 &inV)
Load 3 doubles from memory (reads 64 bits extra which it doesn't use)
Definition DVec3.inl:188
Class that holds 3 doubles. Used as a storage class. Convert to DVec3 for calculations.
Definition Double3.h:13
Class that holds 3 floats. Used as a storage class. Convert to Vec3 for calculations.
Definition Float3.h:13
Describes the mass and inertia properties of a body. Used during body construction only.
Definition MassProperties.h:16
Holds a 4x4 matrix of floats, but supports also operations on the 3x3 upper left part of the matrix.
Definition Mat44.h:13
The Body class only keeps track of state for static bodies, the MotionProperties class keeps the addi...
Definition MotionProperties.h:29
void SetLinearVelocity(Vec3Arg inLinearVelocity)
Set world space linear velocity of the center of mass.
Definition MotionProperties.h:46
uint32 GetIslandIndexInternal() const
Access to the island index.
Definition MotionProperties.h:232
void SetNumVelocityStepsOverride(uint inN)
Used only when this body is dynamic and colliding. Override for the number of solver velocity iterati...
Definition MotionProperties.h:182
void SetAngularVelocityClamped(Vec3Arg inAngularVelocity)
Set world space angular velocity of the center of mass, will make sure the value is clamped against t...
Definition MotionProperties.h:58
Quat GetInertiaRotation() const
Rotation (R) that takes inverse inertia diagonal to local space: .
Definition MotionProperties.h:108
float GetMaxLinearVelocity() const
Maximum linear velocity that a body can achieve. Used to prevent the system from exploding.
Definition MotionProperties.h:67
JPH_INLINE Vec3 GetPointVelocityCOM(Vec3Arg inPointRelativeToCOM) const
Velocity of point inPoint (in center of mass space, e.g. on the surface of the body) of the body (uni...
Definition MotionProperties.h:133
Vec3 GetInverseInertiaDiagonal() const
Diagonal of inverse inertia matrix: D. Should only be called on a dynamic object (static or kinematic...
Definition MotionProperties.h:105
void ApplyAngularVelocityStep(Vec3Arg inAngularVelocity)
Definition MotionProperties.h:222
uint GetNumPositionStepsOverride() const
Definition MotionProperties.h:187
void SetInverseInertia(Vec3Arg inDiagonal, QuatArg inRot)
Definition MotionProperties.h:114
float GetGravityFactor() const
Get gravity factor (1 = normal gravity, 0 = no gravity)
Definition MotionProperties.h:88
void AddLinearVelocityStep(Vec3Arg inLinearVelocityChange)
Definition MotionProperties.h:217
float GetMaxAngularVelocity() const
Maximum angular velocity that a body can achieve. Used to prevent the system from exploding.
Definition MotionProperties.h:71
void SetLinearVelocityClamped(Vec3Arg inLinearVelocity)
Set world space linear velocity of the center of mass, will make sure the value is clamped against th...
Definition MotionProperties.h:49
uint GetNumVelocityStepsOverride() const
Definition MotionProperties.h:183
float GetInverseMassUnchecked() const
Definition MotionProperties.h:96
Vec3 GetLinearVelocity() const
Get world space linear velocity of the center of mass.
Definition MotionProperties.h:43
Vec3 GetAngularVelocity() const
Get world space angular velocity of the center of mass.
Definition MotionProperties.h:52
void SetMaxAngularVelocity(float inAngularVelocity)
Definition MotionProperties.h:72
JPH_INLINE Vec3 LockAngular(Vec3Arg inV) const
Takes an angular velocity / torque vector inV and returns a vector where the components that are not ...
Definition MotionProperties.h:176
JPH_INLINE void ResetMotion()
Definition MotionProperties.h:148
JPH_INLINE Vec3 GetAccumulatedTorque() const
Definition MotionProperties.h:139
void SetIslandIndexInternal(uint32 inIndex)
Definition MotionProperties.h:233
float GetAngularDamping() const
Get angular damping: dw/dt = -c * w. c. Value should be zero or positive and is usually close to 0.
Definition MotionProperties.h:84
void SubLinearVelocityStep(Vec3Arg inLinearVelocityChange)
Definition MotionProperties.h:218
float GetInverseMass() const
Get inverse mass (1 / mass). Should only be called on a dynamic object (static or kinematic bodies ha...
Definition MotionProperties.h:95
void SetGravityFactor(float inGravityFactor)
Definition MotionProperties.h:89
JPH_INLINE UVec4 GetLinearDOFsMask() const
Returns a vector where the linear components that are not allowed by mAllowedDOFs are set to 0 and th...
Definition MotionProperties.h:156
uint32 GetIndexInActiveBodiesInternal() const
Access to the index in the active bodies array.
Definition MotionProperties.h:236
float GetLinearDamping() const
Get linear damping: dv/dt = -c * v. c. Value should be zero or positive and is usually close to 0.
Definition MotionProperties.h:80
void SubAngularVelocityStep(Vec3Arg inAngularVelocityChange)
Definition MotionProperties.h:221
JPH_INLINE void ResetForce()
Definition MotionProperties.h:142
void SetInverseMass(float inInverseMass)
Definition MotionProperties.h:102
void ResetSleepTestTimer()
Reset the sleep test timer without resetting the sleep test spheres.
Definition MotionProperties.h:246
void SetAngularVelocity(Vec3Arg inAngularVelocity)
Set world space angular velocity of the center of mass.
Definition MotionProperties.h:55
void ApplyLinearVelocityStep(Vec3Arg inLinearVelocity)
Definition MotionProperties.h:219
JPH_INLINE Vec3 GetAccumulatedForce() const
Definition MotionProperties.h:136
JPH_INLINE Vec3 LockTranslation(Vec3Arg inV) const
Takes a translation vector inV and returns a vector where the components that are not allowed by mAll...
Definition MotionProperties.h:163
void SetMaxLinearVelocity(float inLinearVelocity)
Definition MotionProperties.h:68
JPH_OVERRIDE_NEW_DELETE EMotionQuality GetMotionQuality() const
Motion quality, or how well it detects collisions when it has a high velocity.
Definition MotionProperties.h:34
void SetLinearDamping(float inLinearDamping)
Definition MotionProperties.h:81
void SetAngularDamping(float inAngularDamping)
Definition MotionProperties.h:85
JPH_INLINE UVec4 GetAngularDOFsMask() const
Returns a vector where the angular components that are not allowed by mAllowedDOFs are set to 0 and t...
Definition MotionProperties.h:169
void SetNumPositionStepsOverride(uint inN)
Used only when this body is dynamic and colliding. Override for the number of solver position iterati...
Definition MotionProperties.h:186
EAllowedDOFs GetAllowedDOFs() const
Get the allowed degrees of freedom that this body has (this can be changed by calling SetMassProperti...
Definition MotionProperties.h:37
bool GetAllowSleeping() const
If this body can go to sleep.
Definition MotionProperties.h:40
void AddAngularVelocityStep(Vec3Arg inAngularVelocityChange)
Definition MotionProperties.h:220
JPH_INLINE void ResetTorque()
Definition MotionProperties.h:145
Definition Quat.h:33
Definition Sphere.h:12
Definition StateRecorder.h:110
Definition UVec4.h:12
static JPH_INLINE UVec4 sReplicate(uint32 inV)
Replicate int inV across all components.
Definition UVec4.inl:75
static JPH_INLINE UVec4 sAnd(UVec4Arg inV1, UVec4Arg inV2)
Logical and (component wise)
Definition UVec4.inl:292
static JPH_INLINE UVec4 sEquals(UVec4Arg inV1, UVec4Arg inV2)
Equals (component wise)
Definition UVec4.inl:198
Definition Vec3.h:17
JPH_INLINE Vec3 Cross(Vec3Arg inV2) const
Cross product.
Definition Vec3.inl:841
JPH_INLINE float Length() const
Length of vector.
Definition Vec3.inl:1000
static JPH_INLINE Vec3 sAnd(Vec3Arg inV1, Vec3Arg inV2)
Logical and (component wise)
Definition Vec3.inl:449
static JPH_INLINE Vec3 sZero()
Vector with all zeros.
Definition Vec3.inl:125
JPH_INLINE bool IsNaN() const
Test if vector contains NaN elements.
Definition Vec3.inl:1133
static JPH_INLINE Vec3 sLoadFloat3Unsafe(const Float3 &inV)
Load 3 floats from memory (reads 32 bits extra which it doesn't use)
Definition Vec3.inl:167