ph::PEmpty Class Reference

#include <PEmpty.h>

Inheritance diagram for ph::PEmpty:

Public Member Functions
	PEmpty ()
bool	isIntersecting (const Ray &ray, HitProbe &probe) const override
	Determine whether a given ray hits the object.
bool	reintersect (const Ray &ray, HitProbe &probe, const Ray &srcRay, HitProbe &srcProbe) const override
	Intersect the intersected object again with a different ray.
void	calcHitDetail (const Ray &ray, HitProbe &probe, HitDetail *out_detail) const override
	Calculates properties of a hit, such as coordinates and normal.
bool	isOccluding (const Ray &ray) const override
	Determines whether this object blocks the ray.
bool	mayOverlapVolume (const math::AABB3D &volume) const override
	Conservatively checks whether this object overlaps a volume.
math::AABB3D	calcAABB () const override
	Calculates Axis-Aligned Bounding Box (AABB) of itself.
Public Member Functions inherited from ph::Primitive
virtual void	genPosSample (PrimitivePosSampleQuery &query, SampleFlow &sampleFlow, HitProbe &probe) const
	Generates a sample point on the surface of this primitive.
virtual void	calcPosPdf (PrimitivePosPdfQuery &query) const
	Given a point on the surface of this primitive, calculates the PDF of sampling this point.
virtual real	calcExtendedArea () const
	Calculates the area extended by this primitive. The term "extended" implies single-sided, e.g., a triangle's extended area is half the absolute value of the cross product of its two edge vectors. To treat it as double-sided, you need to multiply the result by 2 manually.
virtual const PrimitiveMetadata *	getMetadata () const
Public Member Functions inherited from ph::Intersectable
virtual	~Intersectable ()=default

Constructor & Destructor Documentation

PEmpty()

ph::PEmpty::PEmpty ( )

inline

Member Function Documentation

calcAABB()

math::AABB3D ph::PEmpty::calcAABB ( ) const

inlineoverridevirtual

Calculates Axis-Aligned Bounding Box (AABB) of itself.

Implements ph::Primitive.

calcHitDetail()

void ph::PEmpty::calcHitDetail ( const Ray & ray, HitProbe & probe, HitDetail * out_detail ) const

inlineoverridevirtual

Calculates properties of a hit, such as coordinates and normal.

This method calculates a detailed description of a hit from the ray and probe involved in a hit event. For example, the ray and probe used for calling isIntersecting() can be the inputs of this method (if an intersection is found). The process of calculating intersection detail will destroy the input probe.

Parameters

ray	The ray from a hit event.
probe	The probe from a hit event. The process of detail calculation will destroy the probe.
out_detail	Stores the calculated details. This method calculates the essential details only. Some information such as coordinate bases will only be available if specifically requested afterwards (for an example, see HitDetail::computeBases()).

Note

See Primitive for more methods that can generate a hit event.

Warning

This method will destroy the probe.

Implements ph::Primitive.

isIntersecting()

bool ph::PEmpty::isIntersecting ( const Ray & ray, HitProbe & probe ) const

inlineoverridevirtual

Determine whether a given ray hits the object.

Checks whether the specified ray intersects this intersectable. If there is an intersection, true is returned and a brief hit report is stored inside the probe. If there is no intersection, false is returned and the state of the probe is undefined. ray and probe can be used for obtaining hit detail if an intersection is found.

Note

Generates hit event (with ray and probe).

Implements ph::Primitive.

isOccluding()

bool ph::PEmpty::isOccluding ( const Ray & ray ) const

inlineoverridevirtual

Determines whether this object blocks the ray.

If greater performance is desired, you can override the default implementation which simply calls isIntersecting(const Ray&, HitProbe&) const to do the job. The test generally considers the underlying shape as hollow (for closed shape), e.g., a sphere is not occluding a line segment inside the sphere.

This method does not provide any means to retrieve HitDetail. Focusing on testing occlusion can improve performance for some cases.

Reimplemented from ph::Intersectable.

mayOverlapVolume()

bool ph::PEmpty::mayOverlapVolume ( const math::AABB3D & volume ) const

inlineoverridevirtual

Conservatively checks whether this object overlaps a volume.

By conservative, it means true can be returned even though the object does not overlap the volume; but if it actually does, true must be returned. The default implementation performs conservative intersecting test using the AABB calculated by calcAABB(). Although false-positives are allowed for this method, providing an implementation with higher accuracy is benefitial for many algorithms used by the renderer. The test generally considers the underlying shape as hollow (for closed shape), while the volume is solid.

Reimplemented from ph::Intersectable.

reintersect()

bool ph::PEmpty::reintersect ( const Ray & ray, HitProbe & probe, const Ray & srcRay, HitProbe & srcProbe ) const

inlineoverridevirtual

Intersect the intersected object again with a different ray.

This method is different to isIntersecting(const Ray, HitProbe&) const. Given srcRay and srcProbe, this method performs an intersection test against the chain of intersectables recorded in srcProbe (so it is impossible to "discover" new intersectables with this method). Taking BVH as an example, the implementation may only record the intersected object in the probe so this method can bypass the entire BVH traversal.

Parameters

ray	The ray to test for intersection.
probe	The probe to record the intersection.
srcRay	The ray from a previous hit event.
srcProbe	The probe from a hit event. The process of re-intersect will destroy the probe.

Returns

Whether ray intersects the object.

Note

Generates hit event (with ray and probe).

Warning

This method will destroy srcProbe.

Implements ph::Primitive.

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

• Source/Core/Intersection/PEmpty.h