--- /dev/null
+/* === S Y N F I G ========================================================= */
+/*! \file valuenode_segcalctangent.cpp
+** \brief Implementation of the "Segment Tangent" valuenode conversion.
+**
+** $Id$
+**
+** \legal
+** Copyright (c) 2002-2005 Robert B. Quattlebaum Jr., Adrian Bentley
+** Copyright (c) 2007, 2008 Chris Moore
+**
+** This package is free software; you can redistribute it and/or
+** modify it under the terms of the GNU General Public License as
+** published by the Free Software Foundation; either version 2 of
+** the License, or (at your option) any later version.
+**
+** This package is distributed in the hope that it will be useful,
+** but WITHOUT ANY WARRANTY; without even the implied warranty of
+** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+** General Public License for more details.
+** \endlegal
+*/
+/* ========================================================================= */
+
+/* === H E A D E R S ======================================================= */
+
+#ifdef USING_PCH
+# include "pch.h"
+#else
+#ifdef HAVE_CONFIG_H
+# include <config.h>
+#endif
+
+#include "valuenode_segcalctangent.h"
+#include "valuenode_const.h"
+#include "valuenode_composite.h"
+#include "general.h"
+#include "exception.h"
+#include <ETL/hermite>
+#include <ETL/calculus>
+#include "segment.h"
+
+#endif
+
+/* === U S I N G =========================================================== */
+
+using namespace std;
+using namespace etl;
+using namespace synfig;
+
+/* === M A C R O S ========================================================= */
+
+/* === G L O B A L S ======================================================= */
+
+/* === P R O C E D U R E S ================================================= */
+
+/* === M E T H O D S ======================================================= */
+
+ValueNode_SegCalcTangent::ValueNode_SegCalcTangent(const ValueBase::Type &x):
+ LinkableValueNode(x)
+{
+ if(x!=ValueBase::TYPE_VECTOR)
+ throw Exception::BadType(ValueBase::type_local_name(x));
+
+ set_link("segment",ValueNode_Const::create(ValueBase::TYPE_SEGMENT));
+ set_link("amount",ValueNode_Const::create(Real(0.5)));
+}
+
+ValueNode_SegCalcTangent*
+ValueNode_SegCalcTangent::create(const ValueBase &x)
+{
+ return new ValueNode_SegCalcTangent(x.get_type());
+}
+
+ValueNode_SegCalcTangent::~ValueNode_SegCalcTangent()
+{
+ unlink_all();
+}
+
+ValueBase
+ValueNode_SegCalcTangent::operator()(Time t)const
+{
+ if (getenv("SYNFIG_DEBUG_VALUENODE_OPERATORS"))
+ printf("%s:%d operator()\n", __FILE__, __LINE__);
+
+ Segment segment((*segment_)(t).get(Segment()));
+
+ etl::hermite<Vector> curve(segment.p1,segment.p2,segment.t1,segment.t2);
+ etl::derivative< etl::hermite<Vector> > deriv(curve);
+
+ return deriv((*amount_)(t).get(Real()));
+}
+
+
+String
+ValueNode_SegCalcTangent::get_name()const
+{
+ return "segcalctangent";
+}
+
+String
+ValueNode_SegCalcTangent::get_local_name()const
+{
+ return _("Segment Tangent");
+}
+
+bool
+ValueNode_SegCalcTangent::check_type(ValueBase::Type type)
+{
+ return type==ValueBase::TYPE_VECTOR;
+}
+
+bool
+ValueNode_SegCalcTangent::set_link_vfunc(int i,ValueNode::Handle value)
+{
+ assert(i>=0 && i<link_count());
+
+ switch(i)
+ {
+ case 0: CHECK_TYPE_AND_SET_VALUE(segment_, ValueBase::TYPE_SEGMENT);
+ case 1: CHECK_TYPE_AND_SET_VALUE(amount_, ValueBase::TYPE_REAL);
+ }
+ return false;
+}
+
+ValueNode::LooseHandle
+ValueNode_SegCalcTangent::get_link_vfunc(int i)const
+{
+ assert(i>=0 && i<link_count());
+
+ if(i==0)
+ return segment_;
+ if(i==1)
+ return amount_;
+
+ return 0;
+}
+
+int
+ValueNode_SegCalcTangent::link_count()const
+{
+ return 2;
+}
+
+String
+ValueNode_SegCalcTangent::link_name(int i)const
+{
+ assert(i>=0 && i<link_count());
+
+ if(i==0)
+ return "segment";
+ if(i==1)
+ return "amount";
+ return String();
+}
+
+String
+ValueNode_SegCalcTangent::link_local_name(int i)const
+{
+ assert(i>=0 && i<link_count());
+
+ if(i==0)
+ return _("Segment");
+ if(i==1)
+ return _("Amount");
+ return String();
+}
+
+int
+ValueNode_SegCalcTangent::get_link_index_from_name(const String &name)const
+{
+ if(name=="segment")
+ return 0;
+ if(name=="amount")
+ return 1;
+
+ throw Exception::BadLinkName(name);
+}
+
+LinkableValueNode*
+ValueNode_SegCalcTangent::create_new()const
+{
+ return new ValueNode_SegCalcTangent(ValueBase::TYPE_VECTOR);
+}