dust3d/third_party/libigl/include/igl/per_face_normals.h

52 lines
1.9 KiB
C++

// This file is part of libigl, a simple c++ geometry processing library.
//
// Copyright (C) 2013 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_PER_FACE_NORMALS_H
#define IGL_PER_FACE_NORMALS_H
#include "igl_inline.h"
#include <Eigen/Core>
namespace igl
{
// Compute face normals via vertex position list, face list
// Inputs:
// V #V by 3 eigen Matrix of mesh vertex 3D positions
// F #F by 3 eigen Matrix of face (triangle) indices
// Z 3 vector normal given to faces with degenerate normal.
// Output:
// N #F by 3 eigen Matrix of mesh face (triangle) 3D normals
//
// Example:
// // Give degenerate faces (1/3,1/3,1/3)^0.5
// per_face_normals(V,F,Vector3d(1,1,1).normalized(),N);
template <typename DerivedV, typename DerivedF, typename DerivedZ, typename DerivedN>
IGL_INLINE void per_face_normals(
const Eigen::MatrixBase<DerivedV>& V,
const Eigen::MatrixBase<DerivedF>& F,
const Eigen::MatrixBase<DerivedZ> & Z,
Eigen::PlainObjectBase<DerivedN> & N);
// Wrapper with Z = (0,0,0). Note that this means that row norms will be zero
// (i.e. not 1) for degenerate normals.
template <typename DerivedV, typename DerivedF, typename DerivedN>
IGL_INLINE void per_face_normals(
const Eigen::MatrixBase<DerivedV>& V,
const Eigen::MatrixBase<DerivedF>& F,
Eigen::PlainObjectBase<DerivedN> & N);
// Special version where order of face indices is guaranteed not to effect
// output.
template <typename DerivedV, typename DerivedF, typename DerivedN>
IGL_INLINE void per_face_normals_stable(
const Eigen::MatrixBase<DerivedV>& V,
const Eigen::MatrixBase<DerivedF>& F,
Eigen::PlainObjectBase<DerivedN> & N);
}
#ifndef IGL_STATIC_LIBRARY
# include "per_face_normals.cpp"
#endif
#endif