Lightweight flat-array mesh for decimation. More...

Public Member Functions
template<class MeshPtr >
void	build (const MeshPtr &mesh, const std::vector< std::size_t > &pinIndices)

auto	num_alive_verts () const -> std::size_t

auto	num_alive_faces () const -> std::size_t

auto	try_collapse (std::size_t vRemove, std::size_t vKeep, std::vector< std::size_t > *outKeepNbrs=nullptr) -> std::optional< CollapseRecord< T > >
	Try to collapse edge (vRemove → vKeep), returning a collapse record.

auto	collapse_cost (std::size_t v0, std::size_t v1) const -> T

auto	is_alive (std::size_t v) const -> bool

auto	is_collapsible (std::size_t v) const -> bool

auto	vertex_neighbors (std::size_t v) const -> std::vector< std::size_t >

auto	snapshot () const -> HierarchyLevel< T >

auto	rebuild_and_get_edges () -> const std::vector< std::pair< std::size_t, std::size_t > > &

Private Member Functions
void	compute_quadrics_ ()

void	build_edges_ ()

Static Private Member Functions
static auto	computeBarycentric_ (const Vec< T, 3 > &a, const Vec< T, 3 > &b, const Vec< T, 3 > &c, const Vec< T, 3 > &p) -> std::array< T, 3 >

Private Attributes
std::vector< Vec< T, 3 > >	positions_

std::vector< bool >	alive_

std::vector< bool >	is_boundary_

std::vector< bool >	is_pinned_

std::vector< Quadric< T > >	quadrics_

std::vector< std::array< std::size_t, 3 > >	faces_

std::vector< bool >	face_alive_

std::vector< std::vector< std::size_t > >	vert_faces_

std::size_t	num_alive_verts_ {0}

std::size_t	num_alive_faces_ {0}

std::vector< std::pair< std::size_t, std::size_t > >	edges_

std::vector< std::size_t >	scratch_shared_

std::vector< std::size_t >	scratch_remove_

std::vector< std::array< std::size_t, 3 > >	scratch_post_faces_

std::vector< std::size_t >	scratch_nbrs_a_

std::vector< std::size_t >	scratch_nbrs_b_

std::vector< std::size_t >	scratch_shared_nbrs_

Detailed Description

template<typename T>
class OpenABF::detail::hlscm::DecimationMesh< T >

Lightweight flat-array mesh for decimation.

Copies vertex positions and face connectivity from a HalfEdgeMesh into flat vectors, builds adjacency structures, and supports half-edge collapse.

Member Function Documentation

◆ build()

template<typename T >

template<class MeshPtr >

void OpenABF::detail::hlscm::DecimationMesh< T >::build	(	const MeshPtr &	mesh,
		const std::vector< std::size_t > &	pinIndices
	)

inline

Build from a HalfEdgeMesh

◆ build_edges_()

template<typename T >

void OpenABF::detail::hlscm::DecimationMesh< T >::build_edges_ ( )

inlineprivate

Rebuild the unique-edge list from the live faces.

◆ collapse_cost()

template<typename T >

auto OpenABF::detail::hlscm::DecimationMesh< T >::collapse_cost	(	std::size_t	v0,
		std::size_t	v1
	)		const -> T

inline

Compute collapse cost for edge (v0 → v1): Q_merged evaluated at v1

◆ compute_quadrics_()

template<typename T >

void OpenABF::detail::hlscm::DecimationMesh< T >::compute_quadrics_ ( )

inlineprivate

Recompute per-vertex QEM quadrics from the live faces (Garland-Heckbert).

◆ computeBarycentric_()

template<typename T >

static auto OpenABF::detail::hlscm::DecimationMesh< T >::computeBarycentric_	(	const Vec< T, 3 > &	a,
		const Vec< T, 3 > &	b,
		const Vec< T, 3 > &	c,
		const Vec< T, 3 > &	p
	)		-> std::array<T, 3>

inlinestaticprivate

Compute barycentric coordinates of point p in triangle (a, b, c)

◆ is_alive()

template<typename T >

auto OpenABF::detail::hlscm::DecimationMesh< T >::is_alive ( std::size_t v ) const -> bool

inline

Check if a vertex is alive

◆ is_collapsible()

template<typename T >

auto OpenABF::detail::hlscm::DecimationMesh< T >::is_collapsible ( std::size_t v ) const -> bool

inline

Check if a vertex is collapsible (not pinned, alive)

◆ num_alive_faces()

template<typename T >

auto OpenABF::detail::hlscm::DecimationMesh< T >::num_alive_faces ( ) const -> std::size_t

inline

Get number of alive faces

◆ num_alive_verts()

template<typename T >

auto OpenABF::detail::hlscm::DecimationMesh< T >::num_alive_verts ( ) const -> std::size_t

inline

Get number of alive vertices

◆ rebuild_and_get_edges()

template<typename T >

auto OpenABF::detail::hlscm::DecimationMesh< T >::rebuild_and_get_edges ( ) -> const std::vector<std::pair<std::size_t, std::size_t>>&

inline

Rebuild the edge list from alive faces and return it

◆ snapshot()

template<typename T >

auto OpenABF::detail::hlscm::DecimationMesh< T >::snapshot ( ) const -> HierarchyLevel<T>

inline

Take a snapshot of surviving vertices and faces for a hierarchy level

◆ try_collapse()

template<typename T >

auto OpenABF::detail::hlscm::DecimationMesh< T >::try_collapse	(	std::size_t	vRemove,
		std::size_t	vKeep,
		std::vector< std::size_t > *	outKeepNbrs = `nullptr`
	)		-> std::optional<CollapseRecord<T>>

inline

Try to collapse edge (vRemove → vKeep), returning a collapse record.

Returns nullopt if the collapse is invalid.

Parameters

outKeepNbrs Optional out-vector. On a successful collapse it is overwritten with vKeep's post-collapse neighbor vertex indices (sorted, unique). Passing a caller- owned vector here lets the PQ-update path reuse the allocation across collapses instead of letting vertex_neighbors() allocate a fresh vector each time.

◆ vertex_neighbors()

template<typename T >

auto OpenABF::detail::hlscm::DecimationMesh< T >::vertex_neighbors ( std::size_t v ) const -> std::vector<std::size_t>

inline

Get alive neighbour vertices of v (sorted, deduped).

Production code path uses try_collapse's outKeepNbrs out-param to avoid this method's per-call allocation; this overload is retained only as the oracle for the HLSCMInternal.TryCollapse_* tests.

Member Data Documentation

◆ alive_

template<typename T >

std::vector<bool> OpenABF::detail::hlscm::DecimationMesh< T >::alive_

private

Per-vertex alive flag; collapses set entries to false.

◆ edges_

template<typename T >

std::vector<std::pair<std::size_t, std::size_t> > OpenABF::detail::hlscm::DecimationMesh< T >::edges_

private

Unique-edge list, rebuilt on demand by build_edges_().

◆ face_alive_

template<typename T >

std::vector<bool> OpenABF::detail::hlscm::DecimationMesh< T >::face_alive_

private

Per-face alive flag; collapses retire faces by setting entries to false.

◆ faces_

template<typename T >

std::vector<std::array<std::size_t, 3> > OpenABF::detail::hlscm::DecimationMesh< T >::faces_

private

Face connectivity: each face is three vertex indices into positions_.

◆ is_boundary_

template<typename T >

std::vector<bool> OpenABF::detail::hlscm::DecimationMesh< T >::is_boundary_

private

Per-vertex boundary flag, copied from the source mesh.

◆ is_pinned_

template<typename T >

std::vector<bool> OpenABF::detail::hlscm::DecimationMesh< T >::is_pinned_

private

Per-vertex pinned flag; pinned vertices cannot be removed by collapse.

◆ num_alive_faces_

template<typename T >

std::size_t OpenABF::detail::hlscm::DecimationMesh< T >::num_alive_faces_ {0}

private

Count of alive faces (kept current across collapses).

◆ num_alive_verts_

template<typename T >

std::size_t OpenABF::detail::hlscm::DecimationMesh< T >::num_alive_verts_ {0}

private

Count of alive vertices (kept current across collapses).

◆ positions_

template<typename T >

std::vector<Vec<T, 3> > OpenABF::detail::hlscm::DecimationMesh< T >::positions_

private

Per-vertex 3D positions, indexed by original vertex index.

◆ quadrics_

template<typename T >

std::vector<Quadric<T> > OpenABF::detail::hlscm::DecimationMesh< T >::quadrics_

private

Per-vertex QEM quadrics accumulated from incident face planes.

◆ scratch_nbrs_a_

template<typename T >

std::vector<std::size_t> OpenABF::detail::hlscm::DecimationMesh< T >::scratch_nbrs_a_

private

Scratch buffer: neighbor list of one endpoint.

◆ scratch_nbrs_b_

template<typename T >

std::vector<std::size_t> OpenABF::detail::hlscm::DecimationMesh< T >::scratch_nbrs_b_

private

Scratch buffer: neighbor list of the other endpoint.

◆ scratch_post_faces_

template<typename T >

std::vector<std::array<std::size_t, 3> > OpenABF::detail::hlscm::DecimationMesh< T >::scratch_post_faces_

private

Scratch buffer: post-collapse face rewrites.

◆ scratch_remove_

template<typename T >

std::vector<std::size_t> OpenABF::detail::hlscm::DecimationMesh< T >::scratch_remove_

private

Scratch buffer: faces to retire on a collapse.

◆ scratch_shared_

template<typename T >

std::vector<std::size_t> OpenABF::detail::hlscm::DecimationMesh< T >::scratch_shared_

private

Scratch buffer: neighbor indices shared between two endpoints.

◆ scratch_shared_nbrs_

template<typename T >

std::vector<std::size_t> OpenABF::detail::hlscm::DecimationMesh< T >::scratch_shared_nbrs_

private

Scratch buffer: deduplicated union of scratch_nbrs_a_ and scratch_nbrs_b_.

◆ vert_faces_

template<typename T >

std::vector<std::vector<std::size_t> > OpenABF::detail::hlscm::DecimationMesh< T >::vert_faces_

private

Per-vertex incident face list.

Public Member Functions

Private Member Functions

Static Private Member Functions

Private Attributes

Detailed Description

Member Function Documentation

◆ build()

◆ build_edges_()

◆ collapse_cost()

◆ compute_quadrics_()

◆ computeBarycentric_()

◆ is_alive()

◆ is_collapsible()

◆ num_alive_faces()

◆ num_alive_verts()

◆ rebuild_and_get_edges()

◆ snapshot()

◆ try_collapse()

◆ vertex_neighbors()

Member Data Documentation

◆ alive_

◆ edges_

◆ face_alive_

◆ faces_

◆ is_boundary_

◆ is_pinned_

◆ num_alive_faces_

◆ num_alive_verts_

◆ positions_

◆ quadrics_

◆ scratch_nbrs_a_

◆ scratch_nbrs_b_

◆ scratch_post_faces_

◆ scratch_remove_

◆ scratch_shared_

◆ scratch_shared_nbrs_

◆ vert_faces_