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diff --git a/src/live_effects/lpe-pts2ellipse.h b/src/live_effects/lpe-pts2ellipse.h
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+++ b/src/live_effects/lpe-pts2ellipse.h
@@ -0,0 +1,108 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+#ifndef INKSCAPE_LPE_PTS_TO_ELLIPSE_H
+#define INKSCAPE_LPE_PTS_TO_ELLIPSE_H
+
+/** \file
+ * LPE "Points to Ellipse" implementation
+ */
+
+/*
+ * Authors:
+ *   Markus Schwienbacher
+ *
+ * Copyright (C) Markus Schwienbacher 2013 <mschwienbacher@gmail.com>
+ *
+ * Released under GNU GPL v2+, read the file 'COPYING' for more information.
+ */
+
+#include "live_effects/effect.h"
+#include "live_effects/parameter/bool.h"
+#include "live_effects/parameter/enum.h"
+
+#include <gsl/gsl_linalg.h>
+
+
+// struct gsl_vector;
+// struct gsl_permutation;
+
+namespace Inkscape {
+namespace LivePathEffect {
+
+enum EllipseMethod {
+    EM_AUTO,
+    EM_CIRCLE,
+    EM_ISOMETRIC_CIRCLE,
+    EM_PERSPECTIVE_CIRCLE,
+    EM_STEINER_ELLIPSE,
+    EM_STEINER_INELLIPSE,
+    EM_END
+};
+
+class LPEPts2Ellipse : public Effect {
+  public:
+    LPEPts2Ellipse(LivePathEffectObject *lpeobject);
+    ~LPEPts2Ellipse() override;
+
+    Geom::PathVector doEffect_path(Geom::PathVector const &path_in) override;
+
+  private:
+    LPEPts2Ellipse(const LPEPts2Ellipse &) = delete;
+    LPEPts2Ellipse &operator=(const LPEPts2Ellipse &) = delete;
+
+
+    int genIsometricEllipse(std::vector<Geom::Point> const &points_in, Geom::PathVector &path_out);
+
+    int genFitEllipse(std::vector<Geom::Point> const &points_in, Geom::PathVector &path_out);
+
+    int genSteinerEllipse(std::vector<Geom::Point> const &points_in, bool gen_inellipse, Geom::PathVector &path_out);
+
+    int genPerspectiveEllipse(std::vector<Geom::Point> const &points_in, Geom::PathVector &path_out);
+
+    // utility functions
+    static int unit_arc_path(Geom::Path &path_in, Geom::Affine &affine, double start = 0.0,
+                             double end = 2.0 * M_PI, // angles
+                             bool slice = false);
+    static void gen_iso_frame_paths(Geom::PathVector &path_out, const Geom::Affine &affine);
+    static void gen_perspective_frame_paths(Geom::PathVector &path_out, const double rot_angle,
+                                            double projmatrix[3][3]);
+    static void gen_axes_paths(Geom::PathVector &path_out, const Geom::Affine &affine);
+    static void gen_perspective_axes_paths(Geom::PathVector &path_out, const double rot_angle, double projmatrix[3][3]);
+    static bool is_ccw(const std::vector<Geom::Point> &pts);
+    static Geom::Point projectPoint(Geom::Point p, double m[][3]);
+
+    // GUI parameters
+    EnumParam<EllipseMethod> method;
+    BoolParam gen_isometric_frame;
+    BoolParam gen_perspective_frame;
+    BoolParam gen_arc;
+    BoolParam other_arc;
+    BoolParam slice_arc;
+    BoolParam draw_axes;
+    BoolParam draw_perspective_axes;
+    ScalarParam rot_axes;
+    BoolParam draw_ori_path;
+
+    // collect the points from the input paths
+    std::vector<Geom::Point> points;
+
+    // used for solving perspective circle
+    gsl_vector *gsl_x;
+    gsl_permutation *gsl_p;
+    std::vector<Geom::Point> five_pts;
+};
+
+} // namespace LivePathEffect
+} // namespace Inkscape
+
+#endif
+
+/*
+  Local Variables:
+  mode:c++
+  c-file-style:"stroustrup"
+  c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +))
+  indent-tabs-mode:nil
+  fill-column:99
+  End:
+*/
+// vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4 :