1 files changed, 55 insertions, 0 deletions
diff --git a/src/helper/geom-curves.h b/src/helper/geom-curves.h
new file mode 100644
index 0000000..08403e2
--- /dev/null
+++ b/src/helper/geom-curves.h
@@ -0,0 +1,55 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+#ifndef INKSCAPE_HELPER_GEOM_CURVES_H
+#define INKSCAPE_HELPER_GEOM_CURVES_H
+
+/**
+ * @file
+ * Specific curve type functions for Inkscape, not provided by lib2geom.
+ */
+/*
+ * Author:
+ *   Johan Engelen <goejendaagh@zonnet.nl>
+ *
+ * Copyright (C) 2008-2009 Johan Engelen
+ *
+ * Released under GNU GPL v2+, read the file 'COPYING' for more information.
+ */
+
+#include <2geom/line.h>
+#include <2geom/bezier-curve.h>
+
+/// \todo un-inline this function
+inline bool is_straight_curve(Geom::Curve const & c)
+{
+    if( dynamic_cast<Geom::LineSegment const*>(&c) )
+    {
+        return true;
+    }
+    // the curve can be a quad/cubic bezier, but could still be a perfect straight line
+    // if the control points are exactly on the line connecting the initial and final points.
+    Geom::BezierCurve const *curve = dynamic_cast<Geom::BezierCurve const *>(&c);
+    if (curve) {
+        Geom::Line line(curve->initialPoint(), curve->finalPoint());
+        std::vector<Geom::Point> pts = curve->controlPoints();
+        for (unsigned i = 1; i < pts.size() - 1; ++i) {
+            if (!are_near(pts[i], line))
+                return false;
+        }
+        return true;
+    }
+
+    return false;
+}
+
+#endif  // INKSCAPE_HELPER_GEOM_CURVES_H
+
+/*
+  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:fileencoding=utf-8:textwidth=99 :