1 /* === S Y N F I G ========================================================= */
2 /*! \file valuenode_pow.cpp
3 ** \brief Implementation of the "Power" valuenode conversion.
8 ** Copyright (c) 2002-2005 Robert B. Quattlebaum Jr., Adrian Bentley
9 ** Copyright (c) 2007, 2008 Chris Moore
10 ** Copyright (c) 2009 Nikita Kitaev
12 ** This package is free software; you can redistribute it and/or
13 ** modify it under the terms of the GNU General Public License as
14 ** published by the Free Software Foundation; either version 2 of
15 ** the License, or (at your option) any later version.
17 ** This package is distributed in the hope that it will be useful,
18 ** but WITHOUT ANY WARRANTY; without even the implied warranty of
19 ** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
20 ** General Public License for more details.
23 /* ========================================================================= */
25 /* === H E A D E R S ======================================================= */
34 #include "valuenode_pow.h"
35 #include "valuenode_const.h"
40 /* === U S I N G =========================================================== */
44 using namespace synfig;
46 /* === M A C R O S ========================================================= */
48 /* === G L O B A L S ======================================================= */
50 /* === P R O C E D U R E S ================================================= */
52 /* === M E T H O D S ======================================================= */
54 ValueNode_Pow::ValueNode_Pow(const ValueBase &x):
55 LinkableValueNode(x.get_type())
57 Vocab ret(get_children_vocab());
58 set_children_vocab(ret);
59 Real value(x.get(Real()));
60 Real infinity(999999.0);
61 Real epsilon(0.000001);
63 set_link("base", ValueNode_Const::create(Real(value)));
64 set_link("power", ValueNode_Const::create(Real(1)));
65 set_link("epsilon", ValueNode_Const::create(Real(epsilon)));
66 set_link("infinite", ValueNode_Const::create(Real(infinity)));
70 ValueNode_Pow::create(const ValueBase &x)
72 return new ValueNode_Pow(x);
76 ValueNode_Pow::create_new()const
78 return new ValueNode_Pow(get_type());
81 ValueNode_Pow::~ValueNode_Pow()
87 ValueNode_Pow::set_link_vfunc(int i,ValueNode::Handle value)
89 assert(i>=0 && i<link_count());
93 case 0: CHECK_TYPE_AND_SET_VALUE(base_, ValueBase::TYPE_REAL);
94 case 1: CHECK_TYPE_AND_SET_VALUE(power_, ValueBase::TYPE_REAL);
95 case 2: CHECK_TYPE_AND_SET_VALUE(epsilon_, ValueBase::TYPE_REAL);
96 case 3: CHECK_TYPE_AND_SET_VALUE(infinite_, ValueBase::TYPE_REAL);
101 ValueNode::LooseHandle
102 ValueNode_Pow::get_link_vfunc(int i)const
104 assert(i>=0 && i<link_count());
106 if(i==0) return base_;
107 if(i==1) return power_;
108 if(i==2) return epsilon_;
109 if(i==3) return infinite_;
114 ValueNode_Pow::link_count()const
120 ValueNode_Pow::link_local_name(int i)const
122 assert(i>=0 && i<link_count());
124 if(i==0) return _("Base");
125 if(i==1) return _("Power");
126 if(i==2) return _("Epsilon");
127 if(i==3) return _("Infinite");
132 ValueNode_Pow::link_name(int i)const
134 assert(i>=0 && i<link_count());
136 if(i==0) return "base";
137 if(i==1) return "power";
138 if(i==2) return "epsilon";
139 if(i==3) return "infinite";
144 ValueNode_Pow::get_link_index_from_name(const String &name)const
146 if(name=="base") return 0;
147 if(name=="power") return 1;
148 if(name=="epsilon") return 2;
149 if(name=="infinite") return 3;
151 throw Exception::BadLinkName(name);
155 ValueNode_Pow::operator()(Time t)const
157 if (getenv("SYNFIG_DEBUG_VALUENODE_OPERATORS"))
158 printf("%s:%d operator()\n", __FILE__, __LINE__);
160 Real base = (*base_) (t).get(Real());
161 Real power = (*power_) (t).get(Real());
162 Real epsilon = (*epsilon_) (t).get(Real());
163 Real infinite = (*infinite_)(t).get(Real());
167 if (epsilon < 0.00000001)
168 epsilon = 0.00000001;
170 //Filters for special/undefined cases
172 if (abs(power) < epsilon) //x^0 = 1
174 if (abs(base) < epsilon)
176 if (power > 0) //0^x=0
180 if ( ( ((int) power) % 2 != 0) && (base < 0) ) //(-0)^(-odd)=-inf
186 if (base <= epsilon && ((int) power) != power) //negative number to fractional power -> undefined
187 power = ((int) power); //so round off power to nearest integer
189 return pow(base,power);
194 ValueNode_Pow::get_name()const
200 ValueNode_Pow::get_local_name()const
206 ValueNode_Pow::check_type(ValueBase::Type type)
208 return type==ValueBase::TYPE_REAL;
211 LinkableValueNode::Vocab
212 ValueNode_Pow::get_children_vocab_vfunc()const
214 if(children_vocab.size())
215 return children_vocab;
217 LinkableValueNode::Vocab ret;
219 ret.push_back(ParamDesc(ValueBase(),"base")
220 .set_local_name(_("Base"))
221 .set_description(_("The base to be raised to the power"))
224 ret.push_back(ParamDesc(ValueBase(),"power")
225 .set_local_name(_("Power"))
226 .set_description(_("The power used to raise the base"))
229 ret.push_back(ParamDesc(ValueBase(),"epsilon")
230 .set_local_name(_("Epsilon"))
231 .set_description(_("Value used to compare base or power with zero "))
234 ret.push_back(ParamDesc(ValueBase(),"infinite")
235 .set_local_name(_("Infinite"))
236 .set_description(_("Returned value when result tends to infinite"))