// This file is part of libigl, a simple c++ geometry processing library.
// 
// Copyright (C) 2014 Alec Jacobson <alecjacobson@gmail.com>
// 
// This Source Code Form is subject to the terms of the Mozilla Public License 
// v. 2.0. If a copy of the MPL was not distributed with this file, You can 
// obtain one at http://mozilla.org/MPL/2.0/.
#ifndef IGL_SIGNED_DISTANCE_H
#define IGL_SIGNED_DISTANCE_H

#include "igl_inline.h"
#include "AABB.h"
#include "WindingNumberAABB.h"
#include "fast_winding_number.h"
#include <Eigen/Core>
#include <vector>
namespace igl
{
  /// Types of signing a distance field
  enum SignedDistanceType
  {
    /// Use fast pseudo-normal test [Bærentzen & Aanæs 2005]
    SIGNED_DISTANCE_TYPE_PSEUDONORMAL         = 0,
    /// Use winding number [Jacobson, Kavan Sorking-Hornug 2013]
    SIGNED_DISTANCE_TYPE_WINDING_NUMBER       = 1,
    /// Default
    SIGNED_DISTANCE_TYPE_DEFAULT              = 2,
    /// Unsigned (absolute value)
    SIGNED_DISTANCE_TYPE_UNSIGNED             = 3,
    /// Use Fast winding number [Barill, Dickson, Schmidt, Levin, Jacobson 2018]
    SIGNED_DISTANCE_TYPE_FAST_WINDING_NUMBER  = 4,
    /// Total number of signed distance types
    NUM_SIGNED_DISTANCE_TYPE                  = 5
  };
  /// Computes signed distance to a mesh
  ///
  /// @param[in] P  #P by (2|3) list of query point positions
  /// @param[in] V  #V by (2|3) list of vertex positions
  /// @param[in] F  #F by ss list of triangle indices, ss should be 3 unless
  ///   sign_type == SIGNED_DISTANCE_TYPE_UNSIGNED |
  ///   SIGNED_DISTANCE_TYPE_WINDING_NUMBER
  /// @param[in] sign_type  method for computing distance _sign_ S
  /// @param[in] lower_bound  lower bound of distances needed {std::numeric_limits::min}
  /// @param[in] upper_bound  lower bound of distances needed {std::numeric_limits::max}
  /// @param[out] S  #P list of smallest signed distances
  /// @param[out] I  #P list of facet indices corresponding to smallest distances
  /// @param[out] C  #P by (2|3) list of closest points
  /// @param[out] N  #P by (2|3) list of closest normals (only set if
  ///   sign_type=SIGNED_DISTANCE_TYPE_PSEUDONORMAL)
  ///
  /// \bug This only computes distances to triangles. So unreferenced
  /// vertices and degenerate triangles are ignored.
  template <
    typename DerivedP,
    typename DerivedV,
    typename DerivedF,
    typename DerivedS,
    typename DerivedI,
    typename DerivedC,
    typename DerivedN>
  IGL_INLINE void signed_distance(
    const Eigen::MatrixBase<DerivedP> & P,
    const Eigen::MatrixBase<DerivedV> & V,
    const Eigen::MatrixBase<DerivedF> & F,
    const SignedDistanceType sign_type,
    const typename DerivedV::Scalar lower_bound,
    const typename DerivedV::Scalar upper_bound,
    Eigen::PlainObjectBase<DerivedS> & S,
    Eigen::PlainObjectBase<DerivedI> & I,
    Eigen::PlainObjectBase<DerivedC> & C,
    Eigen::PlainObjectBase<DerivedN> & N);
  /// \overload
  template <
    typename DerivedP,
    typename DerivedV,
    typename DerivedF,
    typename DerivedS,
    typename DerivedI,
    typename DerivedC,
    typename DerivedN>
  IGL_INLINE void signed_distance(
    const Eigen::MatrixBase<DerivedP> & P,
    const Eigen::MatrixBase<DerivedV> & V,
    const Eigen::MatrixBase<DerivedF> & F,
    const SignedDistanceType sign_type,
    Eigen::PlainObjectBase<DerivedS> & S,
    Eigen::PlainObjectBase<DerivedI> & I,
    Eigen::PlainObjectBase<DerivedC> & C,
    Eigen::PlainObjectBase<DerivedN> & N);
  /// Computes signed distance to mesh using pseudonormal with precomputed AABB
  /// tree and edge/vertice normals
  ///
  /// @param[in] tree  AABB acceleration tree (see AABB.h)
  /// @param[in] F   #F by 3 list of triangle indices
  /// @param[in] FN  #F by 3 list of triangle normals 
  /// @param[in] VN  #V by 3 list of vertex normals (ANGLE WEIGHTING)
  /// @param[in] EN  #E by 3 list of edge normals (UNIFORM WEIGHTING)
  /// @param[in] EMAP  #F*3 mapping edges in F to E
  /// @param[in] q  Query point
  /// @return signed distance to mesh
  ///
  /// \fileinfo
  template <
    typename DerivedV,
    typename DerivedF,
    typename DerivedFN,
    typename DerivedVN,
    typename DerivedEN,
    typename DerivedEMAP,
    typename Derivedq>
  IGL_INLINE typename DerivedV::Scalar signed_distance_pseudonormal(
    const AABB<DerivedV,3> & tree,
    const Eigen::MatrixBase<DerivedV> & V,
    const Eigen::MatrixBase<DerivedF> & F,
    const Eigen::MatrixBase<DerivedFN> & FN,
    const Eigen::MatrixBase<DerivedVN> & VN,
    const Eigen::MatrixBase<DerivedEN> & EN,
    const Eigen::MatrixBase<DerivedEMAP> & EMAP,
    const Eigen::MatrixBase<Derivedq> & q);
  /// \overload
  ///
  /// \fileinfo
  template <
    typename DerivedP,
    typename DerivedV,
    typename DerivedF,
    typename DerivedFN,
    typename DerivedVN,
    typename DerivedEN,
    typename DerivedEMAP,
    typename DerivedS,
    typename DerivedI,
    typename DerivedC,
    typename DerivedN>
  IGL_INLINE void signed_distance_pseudonormal(
    const Eigen::MatrixBase<DerivedP> & P,
    const Eigen::MatrixBase<DerivedV> & V,
    const Eigen::MatrixBase<DerivedF> & F,
    const AABB<DerivedV,3> & tree,
    const Eigen::MatrixBase<DerivedFN> & FN,
    const Eigen::MatrixBase<DerivedVN> & VN,
    const Eigen::MatrixBase<DerivedEN> & EN,
    const Eigen::MatrixBase<DerivedEMAP> & EMAP,
    Eigen::PlainObjectBase<DerivedS> & S,
    Eigen::PlainObjectBase<DerivedI> & I,
    Eigen::PlainObjectBase<DerivedC> & C,
    Eigen::PlainObjectBase<DerivedN> & N);
  /// \overload
  ///
  /// @param[out] s  sign
  /// @param[out] sqrd  squared distance
  /// @param[out] i  closest primitive
  /// @param[out] c  closest point
  /// @param[out] n  normal
  ///
  /// \fileinfo
  template <
    typename DerivedV,
    typename DerivedF,
    typename DerivedFN,
    typename DerivedVN,
    typename DerivedEN,
    typename DerivedEMAP,
    typename Derivedq,
    typename Scalar,
    typename Derivedc,
    typename Derivedn>
  IGL_INLINE void signed_distance_pseudonormal(
    const AABB<DerivedV,3> & tree,
    const Eigen::MatrixBase<DerivedV> & V,
    const Eigen::MatrixBase<DerivedF> & F,
    const Eigen::MatrixBase<DerivedFN> & FN,
    const Eigen::MatrixBase<DerivedVN> & VN,
    const Eigen::MatrixBase<DerivedEN> & EN,
    const Eigen::MatrixBase<DerivedEMAP> & EMAP,
    const Eigen::MatrixBase<Derivedq> & q,
    Scalar & s,
    Scalar & sqrd,
    int & i,
    Eigen::PlainObjectBase<Derivedc> & c,
    Eigen::PlainObjectBase<Derivedn> & n);
  /// \overload
  template <
    typename DerivedV,
    typename DerivedE,
    typename DerivedEN,
    typename DerivedVN,
    typename Derivedq,
    typename Scalar,
    typename Derivedc,
    typename Derivedn>
  IGL_INLINE void signed_distance_pseudonormal(
    const AABB<DerivedV,2> & tree,
    const Eigen::MatrixBase<DerivedV> & V,
    const Eigen::MatrixBase<DerivedE> & E,
    const Eigen::MatrixBase<DerivedEN> & EN,
    const Eigen::MatrixBase<DerivedVN> & VN,
    const Eigen::MatrixBase<Derivedq> & q,
    Scalar & s,
    Scalar & sqrd,
    int & i,
    Eigen::PlainObjectBase<Derivedc> & c,
    Eigen::PlainObjectBase<Derivedn> & n);
  /// Computes signed distance to mesh using winding number with precomputed AABB
  ///
  /// @param[in] tree  AABB acceleration tree (see cgal/point_mesh_squared_distance.h)
  /// @param[in] hier  Winding number evaluation hierarchy
  /// @param[in] q  Query point
  /// @return signed distance to mesh
  ///
  /// \fileinfo
  template <
    typename DerivedV,
    typename DerivedF,
    typename Derivedq>
  IGL_INLINE typename DerivedV::Scalar signed_distance_winding_number(
    const AABB<DerivedV,3> & tree,
    const Eigen::MatrixBase<DerivedV> & V,
    const Eigen::MatrixBase<DerivedF> & F,
    const igl::WindingNumberAABB<Derivedq,DerivedV,DerivedF> & hier,
    const Eigen::MatrixBase<Derivedq> & q);
  /// \overload
  /// @param[out] s  sign
  /// @param[out] sqrd  squared distance
  /// @param[out] pp  closest point and primitve
  /// \fileinfo
  template <
    typename DerivedV,
    typename DerivedF,
    typename Derivedq,
    typename Scalar,
    typename Derivedc>
  IGL_INLINE void signed_distance_winding_number(
    const AABB<DerivedV,3> & tree,
    const Eigen::MatrixBase<DerivedV> & V,
    const Eigen::MatrixBase<DerivedF> & F,
    const igl::WindingNumberAABB<Derivedq,DerivedV,DerivedF> & hier,
    const Eigen::MatrixBase<Derivedq> & q,
    Scalar & s,
    Scalar & sqrd,
    int & i,
    Eigen::PlainObjectBase<Derivedc> & c);
  /// \overload
  template <
    typename DerivedV,
    typename DerivedF,
    typename Derivedq,
    typename Scalar,
    typename Derivedc>
  IGL_INLINE void signed_distance_winding_number(
    const AABB<DerivedV,2> & tree,
    const Eigen::MatrixBase<DerivedV> & V,
    const Eigen::MatrixBase<DerivedF> & F,
    const Eigen::MatrixBase<Derivedq> & q,
    Scalar & s,
    Scalar & sqrd,
    int & i,
    Eigen::PlainObjectBase<Derivedc> & c);
  /// Calculates signed distance at query points P, using fast winding number
  /// for sign.
  ///
  /// #### Usage:
  ///     VectorXd S;  
  ///     VectorXd V, P; //where V is mesh vertices, P are query points
  ///     VectorXi F;  
  ///     igl::FastWindingNumberBVH fwn_bvh;
  ///     igl::fast_winding_number(V.cast<float>(), F, 2, fwn_bvh);
  ///     igl::signed_distance_fast_winding_number(P,V,F,tree,fwn_bvh,S);
  ///
  /// @param[in] P  #P by 3 list of query point positions
  /// @param[in] V  #V by 3 list of triangle indices
  /// @param[in] F  #F by 3 list of triangle normals 
  /// @param[in] tree  AABB acceleration tree (see AABB.h)
  /// @param[in] bvh fast winding precomputation (see Fast_Winding_Number.h)   
  /// @param[out] S  #P list of signed distances of each point in P
  ///
  /// \fileinfo
  template <
    typename DerivedP,
    typename DerivedV,
    typename DerivedF,
    typename DerivedS>
  IGL_INLINE void signed_distance_fast_winding_number(
    const Eigen::MatrixBase<DerivedP> & P,
    const Eigen::MatrixBase<DerivedV> & V,
    const Eigen::MatrixBase<DerivedF> & F,
    const AABB<DerivedV,3> & tree,
    const igl::FastWindingNumberBVH & fwn_bvh,
    Eigen::PlainObjectBase<DerivedS> & S
  );
  /// Calculates signed distance at query point q, using fast winding number for
  /// sign.
  ///
  /// @param[in] tree  AABB acceleration tree (see AABB.h)
  /// @param[in] V  #V by 3 list of triangle indices
  /// @param[in] F  #F by 3 list of triangle normals 
  /// @param[in] bvh fast winding precomputation (see Fast_Winding_Number.h)   
  /// @param[in] q  1 by 3 list of query point positions
  /// @param[out] S  #P list of signed distances of each point in P
  ///
  /// \fileinfo
  template <
    typename Derivedq,
    typename DerivedV,
    typename DerivedF>
  IGL_INLINE typename DerivedV::Scalar signed_distance_fast_winding_number(
    const Eigen::MatrixBase<Derivedq> & q,
    const Eigen::MatrixBase<DerivedV> & V,
    const Eigen::MatrixBase<DerivedF> & F,
    const AABB<DerivedV,3> & tree,
    const igl::FastWindingNumberBVH & fwn_bvh
  );
}

#ifndef IGL_STATIC_LIBRARY
#  include "signed_distance.cpp"
#endif

#endif