EmptyShape Class Reference

#include <EmptyShape.h>

Inheritance diagram for EmptyShape:

Public Member Functions
	EmptyShape ()
	EmptyShape (Vec3Arg inCenterOfMass)
	EmptyShape (const EmptyShapeSettings &inSettings, ShapeResult &outResult)
Vec3	GetCenterOfMass () const override
	All shapes are centered around their center of mass. This function returns the center of mass position that needs to be applied to transform the shape to where it was created.
AABox	GetLocalBounds () const override
	Get local bounding box including convex radius, this box is centered around the center of mass rather than the world transform.
uint	GetSubShapeIDBitsRecursive () const override
	Get the max number of sub shape ID bits that are needed to be able to address any leaf shape in this shape. Used mainly for checking that it is smaller or equal than SubShapeID::MaxBits.
float	GetInnerRadius () const override
MassProperties	GetMassProperties () const override
	Calculate the mass and inertia of this shape.
const PhysicsMaterial *	GetMaterial (const SubShapeID &inSubShapeID) const override
	Get the material assigned to a particular sub shape ID.
virtual Vec3	GetSurfaceNormal (const SubShapeID &inSubShapeID, Vec3Arg inLocalSurfacePosition) const override
virtual void	GetSubmergedVolume (Mat44Arg inCenterOfMassTransform, Vec3Arg inScale, const Plane &inSurface, float &outTotalVolume, float &outSubmergedVolume, Vec3 &outCenterOfBuoyancy, RVec3Arg inBaseOffset) const override
virtual void	Draw (DebugRenderer *inRenderer, RMat44Arg inCenterOfMassTransform, Vec3Arg inScale, ColorArg inColor, bool inUseMaterialColors, bool inDrawWireframe) const override
	Draw the shape at a particular location with a particular color (debugging purposes)
virtual bool	CastRay (const RayCast &inRay, const SubShapeIDCreator &inSubShapeIDCreator, RayCastResult &ioHit) const override
virtual void	CastRay (const RayCast &inRay, const RayCastSettings &inRayCastSettings, const SubShapeIDCreator &inSubShapeIDCreator, CastRayCollector &ioCollector, const ShapeFilter &inShapeFilter={ }) const override
virtual void	CollidePoint (Vec3Arg inPoint, const SubShapeIDCreator &inSubShapeIDCreator, CollidePointCollector &ioCollector, const ShapeFilter &inShapeFilter={ }) const override
virtual void	CollideSoftBodyVertices (Mat44Arg inCenterOfMassTransform, Vec3Arg inScale, const CollideSoftBodyVertexIterator &inVertices, uint inNumVertices, int inCollidingShapeIndex) const override
virtual void	GetTrianglesStart (GetTrianglesContext &ioContext, const AABox &inBox, Vec3Arg inPositionCOM, QuatArg inRotation, Vec3Arg inScale) const override
virtual int	GetTrianglesNext (GetTrianglesContext &ioContext, int inMaxTrianglesRequested, Float3 *outTriangleVertices, const PhysicsMaterial **outMaterials=nullptr) const override
Stats	GetStats () const override
	Get stats of this shape. Use for logging / data collection purposes only. Does not add values from child shapes, use GetStatsRecursive for this.
float	GetVolume () const override
bool	IsValidScale (Vec3Arg inScale) const override
Public Member Functions inherited from Shape
	Shape (EShapeType inType, EShapeSubType inSubType)
	Constructor.
	Shape (EShapeType inType, EShapeSubType inSubType, const ShapeSettings &inSettings, ShapeResult &outResult)
virtual	~Shape ()=default
	Destructor.
EShapeType	GetType () const
	Get type.
EShapeSubType	GetSubType () const
uint64	GetUserData () const
	User data (to be used freely by the application)
void	SetUserData (uint64 inUserData)
virtual bool	MustBeStatic () const
	Check if this shape can only be used to create a static body or if it can also be dynamic/kinematic.
virtual AABox	GetWorldSpaceBounds (Mat44Arg inCenterOfMassTransform, Vec3Arg inScale) const
AABox	GetWorldSpaceBounds (DMat44Arg inCenterOfMassTransform, Vec3Arg inScale) const
	Get world space bounds including convex radius.
virtual const Shape *	GetLeafShape (const SubShapeID &inSubShapeID, SubShapeID &outRemainder) const
virtual void	GetSupportingFace (const SubShapeID &inSubShapeID, Vec3Arg inDirection, Vec3Arg inScale, Mat44Arg inCenterOfMassTransform, SupportingFace &outVertices) const
virtual uint64	GetSubShapeUserData (const SubShapeID &inSubShapeID) const
	Get the user data of a particular sub shape ID. Corresponds with the value stored in Shape::GetUserData of the leaf shape pointed to by inSubShapeID.
virtual TransformedShape	GetSubShapeTransformedShape (const SubShapeID &inSubShapeID, Vec3Arg inPositionCOM, QuatArg inRotation, Vec3Arg inScale, SubShapeID &outRemainder) const
virtual void	DrawGetSupportFunction (DebugRenderer *inRenderer, RMat44Arg inCenterOfMassTransform, Vec3Arg inScale, ColorArg inColor, bool inDrawSupportDirection) const
	Draw the results of the GetSupportFunction with the convex radius added back on to show any errors introduced by this process (only relevant for convex shapes)
virtual void	DrawGetSupportingFace (DebugRenderer *inRenderer, RMat44Arg inCenterOfMassTransform, Vec3Arg inScale) const
	Draw the results of the GetSupportingFace function to show any errors introduced by this process (only relevant for convex shapes)
virtual void	CollectTransformedShapes (const AABox &inBox, Vec3Arg inPositionCOM, QuatArg inRotation, Vec3Arg inScale, const SubShapeIDCreator &inSubShapeIDCreator, TransformedShapeCollector &ioCollector, const ShapeFilter &inShapeFilter) const
virtual void	TransformShape (Mat44Arg inCenterOfMassTransform, TransformedShapeCollector &ioCollector) const
ShapeResult	ScaleShape (Vec3Arg inScale) const
virtual Stats	GetStatsRecursive (VisitedShapes &ioVisitedShapes) const
	Volume of this shape (m^3). Note that for compound shapes the volume may be incorrect since child shapes can overlap which is not accounted for.
virtual Vec3	MakeScaleValid (Vec3Arg inScale) const
virtual void	SaveBinaryState (StreamOut &inStream) const
	Saves the contents of the shape in binary form to inStream.
virtual void	SaveMaterialState (PhysicsMaterialList &outMaterials) const
	Outputs the material references that this shape has to outMaterials.
virtual void	RestoreMaterialState (const PhysicsMaterialRefC *inMaterials, uint inNumMaterials)
	Restore the material references after calling sRestoreFromBinaryState. Note that the exact same materials need to be provided in the same order as returned by SaveMaterialState.
virtual void	SaveSubShapeState (ShapeList &outSubShapes) const
	Outputs the shape references that this shape has to outSubShapes.
virtual void	RestoreSubShapeState (const ShapeRefC *inSubShapes, uint inNumShapes)
	Restore the shape references after calling sRestoreFromBinaryState. Note that the exact same shapes need to be provided in the same order as returned by SaveSubShapeState.
void	SaveWithChildren (StreamOut &inStream, ShapeToIDMap &ioShapeMap, MaterialToIDMap &ioMaterialMap) const
	Save this shape, all its children and its materials. Pass in an empty map in ioShapeMap / ioMaterialMap or reuse the same map while saving multiple shapes to the same stream in order to avoid writing duplicates.
Public Member Functions inherited from RefTarget< Shape >
	RefTarget ()=default
	Constructor.
	RefTarget (const RefTarget &)
	~RefTarget ()
	assert no one is referencing us
void	SetEmbedded () const
RefTarget &	operator= (const RefTarget &)
	Assignment operator.
uint32	GetRefCount () const
	Get current refcount of this object.
void	AddRef () const
	Add or release a reference to this object.
void	Release () const
Public Member Functions inherited from NonCopyable
	NonCopyable ()=default
	NonCopyable (const NonCopyable &)=delete
void	operator= (const NonCopyable &)=delete

Static Public Member Functions
static void	sRegister ()
Static Public Member Functions inherited from Shape
static ShapeResult	sRestoreFromBinaryState (StreamIn &inStream)
	Creates a Shape of the correct type and restores its contents from the binary stream inStream.
static ShapeResult	sRestoreWithChildren (StreamIn &inStream, IDToShapeMap &ioShapeMap, IDToMaterialMap &ioMaterialMap)
	Restore a shape, all its children and materials. Pass in an empty map in ioShapeMap / ioMaterialMap or reuse the same map while reading multiple shapes from the same stream in order to restore duplicates.
Static Public Member Functions inherited from RefTarget< Shape >
static int	sInternalGetRefCountOffset ()
	INTERNAL HELPER FUNCTION USED BY SERIALIZATION.

Additional Inherited Members
Public Types inherited from Shape
using	ShapeResult = ShapeSettings::ShapeResult
using	SupportingFace = StaticArray< Vec3, 32 >
	Type definition for a supporting face.
using	VisitedShapes = UnorderedSet< const Shape * >
using	ShapeToIDMap = StreamUtils::ObjectToIDMap< Shape >
using	IDToShapeMap = StreamUtils::IDToObjectMap< Shape >
using	MaterialToIDMap = StreamUtils::ObjectToIDMap< PhysicsMaterial >
using	IDToMaterialMap = StreamUtils::IDToObjectMap< PhysicsMaterial >
Static Public Attributes inherited from Shape
static constexpr int	cGetTrianglesMinTrianglesRequested = 32
	This is the minimum amount of triangles that should be requested through GetTrianglesNext.
static bool	sDrawSubmergedVolumes = false
	Debug helper which draws the intersection between water and the shapes, the center of buoyancy and the submerged volume.
Protected Member Functions inherited from Shape
virtual void	RestoreBinaryState (StreamIn &inStream)
	This function should not be called directly, it is used by sRestoreFromBinaryState.
Static Protected Member Functions inherited from Shape
static void	sCollidePointUsingRayCast (const Shape &inShape, Vec3Arg inPoint, const SubShapeIDCreator &inSubShapeIDCreator, CollidePointCollector &ioCollector, const ShapeFilter &inShapeFilter)
	A fallback version of CollidePoint that uses a ray cast and counts the number of hits to determine if the point is inside the shape. Odd number of hits means inside, even number of hits means outside.
Protected Attributes inherited from RefTarget< Shape >
atomic< uint32 >	mRefCount
	Current reference count.
Static Protected Attributes inherited from RefTarget< Shape >
static constexpr uint32	cEmbedded
	A large value that gets added to the refcount to mark the object as embedded.

Detailed Description

An empty shape that has no volume and collides with nothing.

Possible use cases:

• As a placeholder for a shape that will be created later. E.g. if you first need to create a body and only then know what shape it will have.
• If you need a kinematic body to attach a constraint to, but you don't want the body to collide with anything.

Note that, if possible, you should also put your body in an ObjectLayer that doesn't collide with anything. This ensures that collisions will be filtered out at broad phase level instead of at narrow phase level, this is more efficient.

Constructor & Destructor Documentation

EmptyShape() [1/3]

EmptyShape::EmptyShape ( )

inline

EmptyShape() [2/3]

EmptyShape::EmptyShape ( Vec3Arg  inCenterOfMass )

inlineexplicit

EmptyShape() [3/3]

EmptyShape::EmptyShape ( const EmptyShapeSettings &  inSettings, ShapeResult &  outResult  )

inline

Member Function Documentation

CastRay() [1/2]

virtual void EmptyShape::CastRay ( const RayCast &  inRay, const RayCastSettings &  inRayCastSettings, const SubShapeIDCreator &  inSubShapeIDCreator, CastRayCollector &  ioCollector, const ShapeFilter &  inShapeFilter = { }  ) const

inlineoverridevirtual

Cast a ray against this shape. Allows returning multiple hits through ioCollector. Note that this version is more flexible but also slightly slower than the CastRay function that returns only a single hit. If you want the surface normal of the hit use GetSurfaceNormal(collected sub shape ID, inRay.GetPointOnRay(collected faction)).

Implements Shape.

CastRay() [2/2]

virtual bool EmptyShape::CastRay ( const RayCast &  inRay, const SubShapeIDCreator &  inSubShapeIDCreator, RayCastResult &  ioHit  ) const

inlineoverridevirtual

Cast a ray against this shape, returns true if it finds a hit closer than ioHit.mFraction and updates that fraction. Otherwise ioHit is left untouched and the function returns false. Note that the ray should be relative to the center of mass of this shape (i.e. subtract Shape::GetCenterOfMass() from RayCast::mOrigin if you want to cast against the shape in the space it was created). Convex objects will be treated as solid (meaning if the ray starts inside, you'll get a hit fraction of 0) and back face hits against triangles are returned. If you want the surface normal of the hit use GetSurfaceNormal(ioHit.mSubShapeID2, inRay.GetPointOnRay(ioHit.mFraction)).

Implements Shape.

CollidePoint()

virtual void EmptyShape::CollidePoint ( Vec3Arg  inPoint, const SubShapeIDCreator &  inSubShapeIDCreator, CollidePointCollector &  ioCollector, const ShapeFilter &  inShapeFilter = { }  ) const

inlineoverridevirtual

Check if inPoint is inside this shape. For this tests all shapes are treated as if they were solid. Note that inPoint should be relative to the center of mass of this shape (i.e. subtract Shape::GetCenterOfMass() from inPoint if you want to test against the shape in the space it was created). For a mesh shape, this test will only provide sensible information if the mesh is a closed manifold. For each shape that collides, ioCollector will receive a hit.

Implements Shape.

CollideSoftBodyVertices()

virtual void EmptyShape::CollideSoftBodyVertices ( Mat44Arg  inCenterOfMassTransform, Vec3Arg  inScale, const CollideSoftBodyVertexIterator &  inVertices, uint  inNumVertices, int  inCollidingShapeIndex  ) const

inlineoverridevirtual

Collides all vertices of a soft body with this shape and updates SoftBodyVertex::mCollisionPlane, SoftBodyVertex::mCollidingShapeIndex and SoftBodyVertex::mLargestPenetration if a collision with more penetration was found.

Parameters

inCenterOfMassTransform	Center of mass transform for this shape relative to the vertices.
inScale	Scale in local space of the shape (scales relative to its center of mass)
inVertices	The vertices of the soft body
inNumVertices	The number of vertices in inVertices
inCollidingShapeIndex	Value to store in CollideSoftBodyVertexIterator::mCollidingShapeIndex when a collision was found

Implements Shape.

Draw()

void EmptyShape::Draw ( DebugRenderer *  inRenderer, RMat44Arg  inCenterOfMassTransform, Vec3Arg  inScale, ColorArg  inColor, bool  inUseMaterialColors, bool  inDrawWireframe  ) const

overridevirtual

Draw the shape at a particular location with a particular color (debugging purposes)

Implements Shape.

GetCenterOfMass()

Vec3 EmptyShape::GetCenterOfMass ( ) const

inlineoverridevirtual

All shapes are centered around their center of mass. This function returns the center of mass position that needs to be applied to transform the shape to where it was created.

Reimplemented from Shape.

GetInnerRadius()

float EmptyShape::GetInnerRadius ( ) const

inlineoverridevirtual

Returns the radius of the biggest sphere that fits entirely in the shape. In case this shape consists of multiple sub shapes, it returns the smallest sphere of the parts. This can be used as a measure of how far the shape can be moved without risking going through geometry.

Implements Shape.

GetLocalBounds()

AABox EmptyShape::GetLocalBounds ( ) const

inlineoverridevirtual

Get local bounding box including convex radius, this box is centered around the center of mass rather than the world transform.

Implements Shape.

GetMassProperties()

MassProperties EmptyShape::GetMassProperties ( ) const

overridevirtual

Calculate the mass and inertia of this shape.

Implements Shape.

GetMaterial()

const PhysicsMaterial * EmptyShape::GetMaterial ( const SubShapeID &  inSubShapeID ) const

inlineoverridevirtual

Get the material assigned to a particular sub shape ID.

Implements Shape.

GetStats()

Stats EmptyShape::GetStats ( ) const

inlineoverridevirtual

Get stats of this shape. Use for logging / data collection purposes only. Does not add values from child shapes, use GetStatsRecursive for this.

Implements Shape.

GetSubmergedVolume()

virtual void EmptyShape::GetSubmergedVolume ( Mat44Arg  inCenterOfMassTransform, Vec3Arg  inScale, const Plane &  inSurface, float &  outTotalVolume, float &  outSubmergedVolume, Vec3 &  outCenterOfBuoyancy, RVec3Arg  inBaseOffset  ) const

inlineoverridevirtual

Gets the properties needed to do buoyancy calculations for a body using this shape

Parameters

inCenterOfMassTransform	Transform that takes this shape (centered around center of mass) to world space (or a desired other space)
inScale	Scale in local space of the shape (scales relative to its center of mass)
inSurface	The surface plane of the liquid relative to inCenterOfMassTransform
outTotalVolume	On return this contains the total volume of the shape
outSubmergedVolume	On return this contains the submerged volume of the shape
outCenterOfBuoyancy	On return this contains the world space center of mass of the submerged volume
inBaseOffset	The offset to transform inCenterOfMassTransform to world space (in double precision mode this can be used to shift the whole operation closer to the origin). Only used for debug drawing.

Implements Shape.

GetSubShapeIDBitsRecursive()

uint EmptyShape::GetSubShapeIDBitsRecursive ( ) const

inlineoverridevirtual

Get the max number of sub shape ID bits that are needed to be able to address any leaf shape in this shape. Used mainly for checking that it is smaller or equal than SubShapeID::MaxBits.

Implements Shape.

GetSurfaceNormal()

virtual Vec3 EmptyShape::GetSurfaceNormal ( const SubShapeID &  inSubShapeID, Vec3Arg  inLocalSurfacePosition  ) const

inlineoverridevirtual

Get the surface normal of a particular sub shape ID and point on surface (all vectors are relative to center of mass for this shape). Note: When you have a CollideShapeResult or ShapeCastResult you should use -mPenetrationAxis.Normalized() as contact normal as GetSurfaceNormal will only return face normals (and not vertex or edge normals).

Implements Shape.

GetTrianglesNext()

virtual int EmptyShape::GetTrianglesNext ( GetTrianglesContext &  ioContext, int  inMaxTrianglesRequested, Float3 *  outTriangleVertices, const PhysicsMaterial **  outMaterials = nullptr  ) const

inlineoverridevirtual

Call this repeatedly to get all triangles in the box. outTriangleVertices should be large enough to hold 3 * inMaxTriangleRequested entries. outMaterials (if it is not null) should contain inMaxTrianglesRequested entries. The function returns the amount of triangles that it found (which will be <= inMaxTrianglesRequested), or 0 if there are no more triangles. Note that the function can return a value < inMaxTrianglesRequested and still have more triangles to process (triangles can be returned in blocks). Note that the function may return triangles outside of the requested box, only coarse culling is performed on the returned triangles.

Implements Shape.

GetTrianglesStart()

virtual void EmptyShape::GetTrianglesStart ( GetTrianglesContext &  ioContext, const AABox &  inBox, Vec3Arg  inPositionCOM, QuatArg  inRotation, Vec3Arg  inScale  ) const

inlineoverridevirtual

To start iterating over triangles, call this function first. ioContext is a temporary buffer and should remain untouched until the last call to GetTrianglesNext. inBox is the world space bounding in which you want to get the triangles. inPositionCOM/inRotation/inScale describes the transform of this shape. To get the actual triangles call GetTrianglesNext.

Implements Shape.

GetVolume()

float EmptyShape::GetVolume ( ) const

inlineoverridevirtual

Implements Shape.

IsValidScale()

bool EmptyShape::IsValidScale ( Vec3Arg  inScale ) const

inlineoverridevirtual

Test if inScale is a valid scale for this shape. Some shapes can only be scaled uniformly, compound shapes cannot handle shapes being rotated and scaled (this would cause shearing), scale can never be zero. When the scale is invalid, the function will return false.

Here's a list of supported scales:

• SphereShape: Scale must be uniform (signs of scale are ignored).
• BoxShape: Any scale supported (signs of scale are ignored).
• TriangleShape: Any scale supported when convex radius is zero, otherwise only uniform scale supported.
• CapsuleShape: Scale must be uniform (signs of scale are ignored).
• TaperedCapsuleShape: Scale must be uniform (sign of Y scale can be used to flip the capsule).
• CylinderShape: Scale must be uniform in XZ plane, Y can scale independently (signs of scale are ignored).
• RotatedTranslatedShape: Scale must not cause shear in the child shape.
• CompoundShape: Scale must not cause shear in any of the child shapes.

Reimplemented from Shape.

sRegister()

void EmptyShape::sRegister ( )

static

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The documentation for this class was generated from the following files:

• Jolt/Physics/Collision/Shape/EmptyShape.h
• Jolt/Physics/Collision/Shape/EmptyShape.cpp