Merged branch 'dev_native' into lm_sla_supports_auto

Added igl library files

src/igl/ramer_douglas_peucker.cpp

@@ -0,0 +1,150 @@
+#include "ramer_douglas_peucker.h"
+
+#include "LinSpaced.h"
+#include "find.h"
+#include "cumsum.h"
+#include "histc.h"
+#include "slice.h"
+#include "project_to_line.h"
+#include "EPS.h"
+#include "slice_mask.h"
+
+template <typename DerivedP, typename DerivedS, typename DerivedJ>
+IGL_INLINE void igl::ramer_douglas_peucker(
+  const Eigen::MatrixBase<DerivedP> & P,
+  const typename DerivedP::Scalar tol,
+  Eigen::PlainObjectBase<DerivedS> & S,
+  Eigen::PlainObjectBase<DerivedJ> & J)
+{
+  typedef typename DerivedP::Scalar Scalar;
+  // number of vertices
+  const int n = P.rows();
+  // Trivial base case
+  if(n <= 1)
+  {
+    J = DerivedJ::Zero(n);
+    S = P;
+    return;
+  }
+  // number of dimensions
+  const int m = P.cols();
+  Eigen::Array<bool,Eigen::Dynamic,1> I =
+    Eigen::Array<bool,Eigen::Dynamic,1>::Constant(n,1,true);
+  const auto stol = tol*tol;
+  std::function<void(const int,const int)> simplify;
+  simplify = [&I,&P,&stol,&simplify](const int ixs, const int ixe)->void
+  {
+    assert(ixe>ixs);
+    Scalar sdmax = 0;
+    typename Eigen::Matrix<Scalar,Eigen::Dynamic,1>::Index ixc = -1;
+    if((ixe-ixs)>1)
+    {
+      Scalar sdes = (P.row(ixe)-P.row(ixs)).squaredNorm();
+      Eigen::Matrix<Scalar,Eigen::Dynamic,1> sD;
+      const auto & Pblock = P.block(ixs+1,0,((ixe+1)-ixs)-2,P.cols());
+      if(sdes<=EPS<Scalar>())
+      {
+        sD = (Pblock.rowwise()-P.row(ixs)).rowwise().squaredNorm();
+      }else
+      {
+        Eigen::Matrix<Scalar,Eigen::Dynamic,1> T;
+        project_to_line(Pblock,P.row(ixs).eval(),P.row(ixe).eval(),T,sD);
+      }
+      sdmax = sD.maxCoeff(&ixc);
+      // Index full P
+      ixc = ixc+(ixs+1);
+    }
+    if(sdmax <= stol)
+    {
+      if(ixs != ixe-1)
+      {
+        I.block(ixs+1,0,((ixe+1)-ixs)-2,1).setConstant(false);
+      }
+    }else
+    {
+      simplify(ixs,ixc);
+      simplify(ixc,ixe);
+    }
+  };
+  simplify(0,n-1);
+  slice_mask(P,I,1,S);
+  find(I,J);
+}
+
+template <
+  typename DerivedP, 
+  typename DerivedS, 
+  typename DerivedJ,
+  typename DerivedQ>
+IGL_INLINE void igl::ramer_douglas_peucker(
+  const Eigen::MatrixBase<DerivedP> & P,
+  const typename DerivedP::Scalar tol,
+  Eigen::PlainObjectBase<DerivedS> & S,
+  Eigen::PlainObjectBase<DerivedJ> & J,
+  Eigen::PlainObjectBase<DerivedQ> & Q)
+{
+  typedef typename DerivedP::Scalar Scalar;
+  ramer_douglas_peucker(P,tol,S,J);
+  const int n = P.rows();
+  assert(n>=2 && "Curve should be at least 2 points");
+  typedef Eigen::Matrix<Scalar,Eigen::Dynamic,1> VectorXS;
+  // distance traveled along high-res curve
+  VectorXS L(n);
+  L(0) = 0;
+  L.block(1,0,n-1,1) = (P.bottomRows(n-1)-P.topRows(n-1)).rowwise().norm();
+  // Give extra on end
+  VectorXS T;
+  cumsum(L,1,T);
+  T.conservativeResize(T.size()+1);
+  T(T.size()-1) = T(T.size()-2);
+  // index of coarse point before each fine vertex
+  Eigen::VectorXi B;
+  {
+    Eigen::VectorXi N;
+    histc(igl::LinSpaced<Eigen::VectorXi >(n,0,n-1),J,N,B);
+  }
+  // Add extra point at end
+  J.conservativeResize(J.size()+1);
+  J(J.size()-1) = J(J.size()-2);
+  Eigen::VectorXi s,d;
+  // Find index in original list of "start" vertices
+  slice(J,B,s);
+  // Find index in original list of "destination" vertices
+  slice(J,(B.array()+1).eval(),d);
+  // Parameter between start and destination is linear in arc-length
+  VectorXS Ts,Td;
+  slice(T,s,Ts);
+  slice(T,d,Td);
+  T = ((T.head(T.size()-1)-Ts).array()/(Td-Ts).array()).eval();
+  for(int t =0;t<T.size();t++)
+  {
+    if(!std::isfinite(T(t)) || T(t)!=T(t))
+    {
+      T(t) = 0;
+    }
+  }
+  DerivedS SB;
+  slice(S,B,1,SB);
+  Eigen::VectorXi MB = B.array()+1;
+  for(int b = 0;b<MB.size();b++)
+  {
+    if(MB(b) >= S.rows())
+    {
+      MB(b) = S.rows()-1;
+    }
+  }
+  DerivedS SMB;
+  slice(S,MB,1,SMB);
+  Q = SB.array() + ((SMB.array()-SB.array()).colwise()*T.array());
+
+  // Remove extra point at end
+  J.conservativeResize(J.size()-1);
+}
+
+#ifdef IGL_STATIC_LIBRARY
+// Explicit template instantiation
+// generated by autoexplicit.sh
+template void igl::ramer_douglas_peucker<Eigen::Matrix<double, -1, -1, 0, -1, -1>, Eigen::Matrix<double, -1, -1, 0, -1, -1>, Eigen::Matrix<int, -1, 1, 0, -1, 1>, Eigen::Matrix<double, -1, -1, 0, -1, -1> >(Eigen::MatrixBase<Eigen::Matrix<double, -1, -1, 0, -1, -1> > const&, Eigen::Matrix<double, -1, -1, 0, -1, -1>::Scalar, Eigen::PlainObjectBase<Eigen::Matrix<double, -1, -1, 0, -1, -1> >&, Eigen::PlainObjectBase<Eigen::Matrix<int, -1, 1, 0, -1, 1> >&, Eigen::PlainObjectBase<Eigen::Matrix<double, -1, -1, 0, -1, -1> >&);
+// generated by autoexplicit.sh
+template void igl::ramer_douglas_peucker<Eigen::Matrix<double, -1, 2, 0, -1, 2>, Eigen::Matrix<double, -1, 2, 0, -1, 2>, Eigen::Matrix<int, -1, 1, 0, -1, 1>, Eigen::Matrix<double, -1, 2, 0, -1, 2> >(Eigen::MatrixBase<Eigen::Matrix<double, -1, 2, 0, -1, 2> > const&, Eigen::Matrix<double, -1, 2, 0, -1, 2>::Scalar, Eigen::PlainObjectBase<Eigen::Matrix<double, -1, 2, 0, -1, 2> >&, Eigen::PlainObjectBase<Eigen::Matrix<int, -1, 1, 0, -1, 1> >&, Eigen::PlainObjectBase<Eigen::Matrix<double, -1, 2, 0, -1, 2> >&);
+#endif