SimWildMesh.h

#pragma once
 
#include <igl/Timer.h>
#include <wmtk/SurfaceTagAttributes.h>
#include <wmtk/TetMesh.h>
#include <wmtk/TetOptimizerMesh.h>
#include <wmtk/utils/PartitionMesh.h>
#include <polysolve/nonlinear/Problem.hpp>
#include <wmtk/envelope/Envelope.hpp>
#include <wmtk/optimization/SmoothVertex.hpp>
#include <wmtk/optimization/solver.hpp>
#include <wmtk/simplex/Simplex.hpp>
#include <wmtk/threading/enumerable_thread_specific.hpp>
#include <wmtk/threading/parallel_for.hpp>
 
#include "ConnectedComponent.hpp"
#include "Parameters.h"
 
// clang-format off
#include <wmtk/utils/DisableWarnings.hpp>
#include <fastenvelope/FastEnvelope.h>
#include <VolumeRemesher/embed.h>
#include <wmtk/utils/EnableWarnings.hpp>
// clang-format on
 
#include <igl/remove_unreferenced.h>
#include <atomic>
#include <memory>
 
#include <wmtk/utils/SurfaceTopology.hpp>
#include <wmtk/utils/partition_utils.hpp>
#include "expression_parser/Expression.hpp"
 
namespace wmtk::components::simwild {
 
using VertexAttributes = wmtk::TetOptimizerMesh::VertexAttributes;
using FaceAttributes = wmtk::TetOptimizerMesh::FaceAttributes;
 
class TetAttributes
{
public:
    double m_quality;
    CellTag tags;
};
 
class SimWildMesh : public wmtk::TetOptimizerMesh
{
public:
    using ExprPtr = expression_parser::ExpressionPtr;
 
    size_t m_tags_count = 0;
    std::map<int64_t, std::string> m_tag_id_to_name;
    std::map<std::string, int64_t> m_tag_name_to_id;
 
    Parameters& m_sim_params;
    std::vector<Vector3d> m_V_envelope;
    std::vector<Vector3i> m_F_envelope;
    double m_envelope_eps = -1;
 
    std::vector<std::tuple<ExprPtr, double>> m_sizing_field;
    std::vector<std::tuple<ExprPtr, double>> m_quality_field;
 
    bool m_collapse_check_quality = true;
 
    // for open boundary
    std::shared_ptr<SampleEnvelope> m_order_2_edge_envelope;
 
    std::shared_ptr<SampleEnvelope> smoothing_energy_envelope(const size_t vid) const override;
 
    // When set, split_edge_after binary-searches vmid onto the zero-crossing of this function.
    // Negative = stays on v1 side, positive = stays on v2 side.
    std::function<double(const Vector3d&)> m_voronoi_split_fn = nullptr;
 
    SimWildMesh(Parameters& _m_params, double envelope_eps, int _num_threads = 0)
        : wmtk::TetOptimizerMesh(_m_params, nullptr)
        , m_sim_params(_m_params)
    {
        m_envelope_eps = envelope_eps;
        NUM_THREADS = _num_threads;
        p_tet_attrs = &m_tet_attribute;
        m_collapse_check_link_condition = false;
        m_collapse_check_manifold = false;
 
        // solver is lazily created on first use
 
        optimization::deactivate_opt_logger();
 
        m_s_envelope = 1. / (m_params.eps * m_params.eps);
 
        double& wa = m_params.w_amips;
        double& we = m_params.w_envelope;
        we = 1 - wa;
        logger().info("w_envelope = {}", we);
    }
 
    ~SimWildMesh() {}
    using TetAttCol = wmtk::AttributeCollection<TetAttributes>;
    TetAttCol m_tet_attribute;
 
    double cell_quality(const size_t tid) const override { return m_tet_attribute[tid].m_quality; }
    void set_cell_quality(const size_t tid, const double q) override
    {
        m_tet_attribute[tid].m_quality = q;
    }
    bool allow_surface_swap() const override { return m_sim_params.allow_surface_swap; }
    bool check_surface_topology() const override { return m_sim_params.check_surface_topology; }
 
    // only used with unit tests
    void create_mesh_attributes(
        const std::vector<VertexAttributes>& _vertex_attribute,
        const std::vector<TetAttributes>& _tet_attribute)
    {
        const size_t n_tet = _tet_attribute.size();
        m_vertex_attribute.resize(_vertex_attribute.size());
        m_face_attribute.resize(4 * n_tet);
        m_tet_attribute.resize(n_tet);
 
        for (size_t i = 0; i < _vertex_attribute.size(); i++)
            m_vertex_attribute[i] = _vertex_attribute[i];
 
        // Keep whatever init() reserved. AttributeCollection::resize only ever grows, so the
        // calls above cannot shrink a collection -- but assigning m_attributes directly does,
        // and it used to drop the tet attributes to exactly n_tet. The attributes have to stay
        // at least as large as the connectivity: an operation that creates a new element
        // indexes them by its id, and a 5->6 swap creates one. tetwild hit the same thing (see
        // the note on its copy); there the overrun wrote a double past the end and libc++ let
        // it pass, here it assigns a std::set and segfaults outright.
        const size_t tcap = std::max(n_tet, m_tet_attribute.size());
        m_tet_attribute.m_attributes = std::vector<TetAttributes>(tcap);
        for (size_t i = 0; i < n_tet; i++) m_tet_attribute[i] = _tet_attribute[i];
        for (size_t i = 0; i < n_tet; i++)
            m_tet_attribute[i].m_quality = get_quality(tuple_from_tet(i));
    }
 
    // TODO This should not be here but inside wmtk
    // TODO This should not be here but inside wmtk
    void init_envelope(const MatrixXd& V, const MatrixXi& F, const bool use_exact);
 
    CellTag string_set_to_cell_tag(const std::set<std::string>& str_set);
 
    void set_sizing_field(const nlohmann::json& sizing_field_json);
 
    void set_quality_field(const nlohmann::json& quality_field_json);
 
    double target_quality(const size_t tid) const;
    double target_quality(const Tuple& t) const;
    double quality_rel(const size_t tid) const override;
    double quality_rel(const Tuple& t) const;
    bool check_mesh_quality(double& max_rel_quality, const bool verbose = false) const;
    std::vector<size_t> active_vertices() const override;
 
 
 
    void write_msh(std::string file, const bool write_envelope = true);
 
public:
    void simplify();
 
    bool all_rounded() const;
 
    //
    //
    // debug use
    std::atomic<int> cnt_split = 0, cnt_collapse = 0;
 
protected:
    std::tuple<double, double> optimization_quality_stats() override;
    double optimization_stop_metric() const override { return 1.; }
    bool optimization_stop_at_float() const override { return m_sim_params.stop_at_float; }
    void write_optimization_debug_output(const std::string& path) override { write_vtu(path); }
 
    bool collapse_before_vertex(size_t v1, size_t v2, double edge_length) override;
    bool collapse_quality_allowed(size_t v1, double quality, double ring_max) const override;
    bool collapse_is_order_2_edge(const std::array<size_t, 2>& e) override;
    bool collapse_after_connectivity(
        size_t v1,
        size_t v2,
        const std::vector<std::array<size_t, 2>>& boundary_edges) override;
    void collapse_after_vertex(size_t v1, size_t v2) override;
 
    bool split_before_cells(const Tuple& edge, const std::vector<Tuple>& parents) override;
    bool split_after_cells(size_t v1, size_t v2, size_t v_new, const std::vector<Tuple>& children)
        override;
    bool split_adjust_position(size_t v_new, const std::vector<Tuple>& children) override;
 
    bool swap_before_interior(const std::vector<size_t>& tids) override;
    bool swap_before_surface(
        const std::vector<size_t>& tids,
        size_t a,
        size_t b,
        size_t c,
        size_t d) override;
    bool swap_after_cells(const std::vector<size_t>& tids, bool is_surface_flip) override;
 
private:
 
    struct SplitTagCache
    {
        size_t v_new = 0;
        std::map<simplex::Edge, TetAttributes> tets;
    };
    wmtk::threading::enumerable_thread_specific<SplitTagCache> split_tag_cache;
 
    struct SwapTagCache
    {
        CellTag tet_tags;
        std::map<size_t, CellTag> ring_tags;
    };
    wmtk::threading::enumerable_thread_specific<SwapTagCache> swap_tag_cache;
 
public:
    void init_from_image(
        const MatrixXr& V,
        const MatrixXi& T,
        const MatrixSi& T_tags,
        const std::vector<std::string>& tag_names);
    void init_from_image(
        const MatrixXd& V,
        const MatrixXi& T,
        const MatrixSi& T_tags,
        const std::vector<std::string>& tag_names);
 
    void init_surfaces_and_boundaries();
 
 
    size_t refine_sizing_around_worst(double max_metric = 0.) override;
 
 
    void find_order_2_edges();
    bool is_order_2_edge(const Tuple& e) const;
    bool is_order_2_edge(const std::array<size_t, 2>& e) const;
 
    void write_vtu(const std::string& path);
 
    void write_surface(const std::string& path) const;
 
public:
    // substructure functions
 
    void init_vertex_order();
 
public:
    // Annotations
 
    double tet_volume(const size_t tid) const;
 
    std::vector<ConnectedComponent> compute_connected_components(const CellTag& tag_in) const;
    std::vector<ConnectedComponent> compute_connected_components(const ExprPtr& expr) const;
 
    std::vector<ConnectedComponent> find_holes(const std::vector<CellTag>& tag_in) const;
 
    void compute_tag_boundary(const CellTag& tag, MatrixXd& V, MatrixXi& F) const;
 
    void keep_largest_connected_component(
        const std::vector<CellTag>& lcc_tags,
        const size_t n_lcc = 1);
 
    void fill_holes_topo(
        const std::vector<CellTag>& fill_holes_tags,
        double threshold = std::numeric_limits<double>::infinity());
 
    void seal_connected_components(
        const std::vector<CellTag>& tag_sets,
        const std::vector<ConnectedComponent>& components);
 
    void tight_seal_topo(
        const std::vector<std::vector<CellTag>>& tight_seal_tag_sets,
        double threshold = std::numeric_limits<double>::infinity());
 
    void resolve_overlaps(const std::vector<std::array<ExprPtr, 2>>& intersecting_tags);
 
    void replace_tags(const std::vector<CellTag>& tags_in, const std::vector<CellTag>& tags_out);
 
    void tag_priority(const std::vector<int64_t>& tags);
};
 
} // namespace wmtk::components::simwild