SoA (Structure of Arrays) layout for W triangles, enabling SIMD evaluation. More...

#include <EBGeometry_TriangleSoA.hpp>

Inheritance diagram for EBGeometry::TriangleSoAT< T, W >:

Public Member Functions
template<class Meta >
void	pack (const Triangle< T, Meta > *tris, uint32_t count) noexcept
	Pack count triangles from tris[0..count-1] into this SoA group.

T	signedDistance (const Vec3T< T > &a_point) const noexcept
	Evaluate signed distance from a_point to the closest triangle in this group.

std::array< T, W >	signedDistances (const Vec3T< T > &a_point) const noexcept
	Signed distances from a_point to every one of the W lane triangles.

template<class BV >
BV	computeBoundingVolume () const noexcept
	Compute the bounding volume enclosing all valid triangles in this group.

Protected Member Functions
T	signedDistanceLane (uint32_t a_lane, const Vec3T< T > &a_point) const noexcept
	Signed distance from a_point to the single triangle stored in lane a_lane.

Protected Attributes
T	m_vx [3][W]
	x-coordinates of vertex positions. m_vx[i][j] = x-coord of vertex i for triangle j.

T	m_vy [3][W]
	y-coordinates of vertex positions. m_vy[i][j] = y-coord of vertex i for triangle j.

T	m_vz [3][W]
	z-coordinates of vertex positions. m_vz[i][j] = z-coord of vertex i for triangle j.

T	m_nx [W]
	x-components of face normals. m_nx[j] = x-component of the face normal for triangle j.

T	m_ny [W]
	y-components of face normals.

T	m_nz [W]
	z-components of face normals.

T	m_vnx [3][W]
	x-components of vertex normals. m_vnx[i][j] = x of vertex normal i for triangle j.

T	m_vny [3][W]
	y-components of vertex normals. m_vny[i][j] = y of vertex normal i for triangle j.

T	m_vnz [3][W]
	z-components of vertex normals. m_vnz[i][j] = z of vertex normal i for triangle j.

T	m_enx [3][W]
	x-components of edge normals. m_enx[i][j] = x of edge normal i for triangle j.

T	m_eny [3][W]
	y-components of edge normals. m_eny[i][j] = y of edge normal i for triangle j.

T	m_enz [3][W]
	z-components of edge normals. m_enz[i][j] = z of edge normal i for triangle j.

uint32_t	m_validCount = 0
	Number of valid (non-padded) triangles in this group (1..W).

Detailed Description

template<class T, size_t W>
struct EBGeometry::TriangleSoAT< T, W >

SoA (Structure of Arrays) layout for W triangles, enabling SIMD evaluation.

signedDistance() dispatches to a packed intrinsics path for (T,W) combinations that fill a SIMD register exactly — SSE4.1 (float, W=4), AVX (float, W=8; double, W=4 or W=8), or AVX-512F (float, W=16; double, W=8) — evaluating all W triangles simultaneously. Any other (T,W) falls back to a scalar loop over m_validCount triangles.

Warning: This type is over-aligned (up to 64 bytes, for AVX-512F) via alignas. The library's own usage (PackedBVH storing groups inside a std::vector<TriangleSoAT>) is safe: C++17 mandates that std::allocator respect over-alignment, which has been verified empirically for every (T,W) combination this class supports. If you allocate a TriangleSoAT yourself outside of that path — a raw new, a container with a custom/pre-C++17-style allocator, placement-new into externally-owned storage, or a malloc'd buffer — you are responsible for ensuring the memory is aligned to alignof(TriangleSoAT<T, W>); nothing in this class enforces or checks that, and a misaligned SIMD load will crash (or silently read the wrong data on some platforms) rather than failing gracefully.

Template Parameters

T	Floating-point precision.
W	SIMD width: 4 for SSE (128-bit), 8 for AVX (256-bit float) or AVX-512F (512-bit double), 16 for AVX-512F (512-bit float).

Member Function Documentation

◆ computeBoundingVolume()

template<class T , size_t W>

template<class BV >

BV EBGeometry::TriangleSoAT< T, W >::computeBoundingVolume ( ) const

noexcept

Compute the bounding volume enclosing all valid triangles in this group.

Requires the group to have already been packed via pack() (1 <= m_validCount <= W).

Template Parameters

BV	Bounding volume type (e.g. AABBT<T>); must be constructible from a std::vector<Vec3T<T>> of vertex positions.

Returns: Bounding volume enclosing all vertices of the m_validCount triangles.

◆ pack()

template<class T , size_t W>

template<class Meta >

void EBGeometry::TriangleSoAT< T, W >::pack	(	const Triangle< T, Meta > *	tris,
		uint32_t	count
	)

noexcept

Pack count triangles from tris[0..count-1] into this SoA group.

Pads lanes count..W-1 by repeating the last real triangle so that all W lanes hold valid data and SIMD loads never read uninitialised memory.

Template Parameters

Meta	Triangle meta-data type (forwarded from Triangle<T,Meta>).

Parameters

[in]	tris	Source triangle array with at least count elements. Must not be null.
[in]	count	Number of valid triangles to pack. Must satisfy 1 <= count <= W.

◆ signedDistance()

template<class T , size_t W>

T EBGeometry::TriangleSoAT< T, W >::signedDistance ( const Vec3T< T > & a_point ) const

noexcept

Evaluate signed distance from a_point to the closest triangle in this group.

Returns the signed distance with minimum absolute value among m_validCount triangles. Dispatches to an SSE4.1 packed-float path for (T=float, W=4), to AVX packed-float for (T=float, W=8), to AVX packed-double for (T=double, W=4 or W=8), or to a scalar fallback. Requires the group to have already been packed via pack() (1 <= m_validCount <= W).

Parameters

[in] a_point Query point. Must be finite.

Returns: Signed distance from a_point to the closest valid triangle, with sign determined by the outward normal of the nearest feature (face, edge, or vertex).

◆ signedDistanceLane()

template<class T , size_t W>

T EBGeometry::TriangleSoAT< T, W >::signedDistanceLane	(	uint32_t	a_lane,
		const Vec3T< T > &	a_point
	)		const

protectednoexcept

Signed distance from a_point to the single triangle stored in lane a_lane.

The scalar per-lane kernel shared by the scalar fallback of signedDistance() and by signedDistances(). Reads only lane a_lane's coordinates/normals; performs no reduction.

Parameters

[in]	a_lane	Lane index. Must satisfy 0 <= a_lane < W.
[in]	a_point	Query point.

Returns: Signed distance from a_point to lane a_lane's triangle, sign from its nearest feature.

◆ signedDistances()

template<class T , size_t W>

std::array< T, W > EBGeometry::TriangleSoAT< T, W >::signedDistances ( const Vec3T< T > & a_point ) const

noexcept

Signed distances from a_point to every one of the W lane triangles.

The per-lane analogue of signedDistance(): signedDistance() horizontally reduces the W per-triangle distances to the single minimum-|value| entry, whereas this returns all W of them so a caller can recover which lane won – the piece the SIMD reduction discards. Computed with a scalar per-lane loop rather than the SIMD kernel, since it is used only by the metadata-retrieving (non-throughput) path. All W lanes are filled: padded lanes (m_validCount..W-1) repeat the last real triangle's distance, matching pack()'s padding, so a caller iterating lanes should stop at m_validCount (or de-duplicate). Requires the group to have already been packed via pack() (1 <= m_validCount <= W).

Parameters

[in] a_point Query point. Must be finite.

Returns: Per-lane signed distances, one per W lanes.

Member Data Documentation

◆ m_validCount

template<class T , size_t W>

uint32_t EBGeometry::TriangleSoAT< T, W >::m_validCount = 0

protected

Number of valid (non-padded) triangles in this group (1..W).

Zero-initialized so that a default-constructed (not-yet-packed) group reliably fails the EBGEOMETRY_EXPECT(m_validCount >= 1) precondition in signedDistance() and computeBoundingVolume(), rather than reading whatever indeterminate value happened to be there.

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

Source/EBGeometry_TriangleSoA.hpp

Public Member Functions

Protected Member Functions

Protected Attributes

Detailed Description

Member Function Documentation

◆ computeBoundingVolume()

◆ pack()

◆ signedDistance()

◆ signedDistanceLane()

◆ signedDistances()

Member Data Documentation

◆ m_validCount