ImplicitSurfaceNetwork/primitive_process/interface/subface/simple/sphere_face.hpp

#pragma once

#include <base/subface.hpp>

namespace internal
{
// local: a sphere with center at (0, 0, 0) and radius 1
struct sphere_face_t final : subface {
    static constexpr uint64_t             max_degree  = 2;
    static constexpr equation_system_type eq_sys_type = equation_system_type::implicit;

    std::function<double(Eigen::Vector3d)>          fetch_sdf_evaluator() const override;
    std::function<Eigen::Vector3d(Eigen::Vector3d)> fetch_sdf_grad_evaluator() const override;

    // u: planar angle from x-axis to z-axis
    // v: polar angle from xz-plane to y-axis
    std::function<Eigen::Vector4d(Eigen::Vector2d)> fetch_point_by_param_evaluator() const override;
    std::function<Eigen::Vector2d(Eigen::Vector4d)> fetch_param_mapping_evaluator() const override;

    std::function<constraint_curve_intermediate(double)> fetch_curve_constraint_evaluator(parameter_u_t constraint_var_type,
                                                                                          double        u) const override;
    std::function<constraint_curve_intermediate(double)> fetch_curve_constraint_evaluator(parameter_v_t constraint_var_type,
                                                                                          double        v) const override;
    std::function<equation_intermediate_t(constraint_curve_intermediate &&)> fetch_solver_evaluator() const override;

    Eigen::AlignedBox3d local_aabb() const override
    {
        return Eigen::AlignedBox3d(Eigen::Vector3d(-1, -1, -1), Eigen::Vector3d(1, 1, 1));
    }
};
} // namespace internal

namespace detail
{
template <>
struct default_elem_ctor<internal::paired_model_matrix *, internal::sphere_face_t> {
    internal::sphere_face_t operator()(const internal::paired_model_matrix *k) const
    {
        internal::sphere_face_t res{};
        res.model_matrices = const_cast<internal::paired_model_matrix *>(k);
        return res;
    }
};
} // namespace detail