claw  1.9.0
single_tweener.cpp
1 /*
2  CLAW - a C++ Library Absolutely Wonderful
3 
4  CLAW is a free library without any particular aim but being useful to
5  anyone.
6 
7  Copyright (C) 2005-2011 Julien Jorge
8 
9  This library is free software; you can redistribute it and/or
10  modify it under the terms of the GNU Lesser General Public
11  License as published by the Free Software Foundation; either
12  version 2.1 of the License, or (at your option) any later version.
13 
14  This library is distributed in the hope that it will be useful,
15  but WITHOUT ANY WARRANTY; without even the implied warranty of
16  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17  Lesser General Public License for more details.
18 
19  You should have received a copy of the GNU Lesser General Public
20  License along with this library; if not, write to the Free Software
21  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
22  contact: julien.jorge@stuff-o-matic.com
23 */
30 
31 #include <algorithm>
32 
37  : m_date(0)
38  , m_easing(easing_none::ease_in_out)
39 {}
40 
50  double duration,
51  update_function callback,
53  : m_init(init)
54  , m_end(end)
55  , m_date(0)
56  , m_duration(duration)
57  , m_callback(callback)
58  , m_easing(e)
59 {}
60 
69  double duration, easing_function e)
70  : m_init(val)
71  , m_end(end)
72  , m_date(0)
73  , m_duration(duration)
74  , m_easing(e)
75 {
76  m_callback = [&val](double v) -> void
77  {
78  val = v;
79  };
80 }
81 
86 {
87  return m_init;
88 }
89 
95 {
96  m_init = v;
97 }
98 
103 {
104  return m_end;
105 }
106 
112 {
113  m_end = v;
114 }
115 
120 {
121  return m_duration;
122 }
123 
129 {
130  m_duration = v;
131 }
132 
138 {
139  m_callback = f;
140 }
141 
147 {
148  m_easing = f;
149 }
150 
155 {
156  const double coeff = m_easing(m_date / m_duration);
157  return m_init + coeff * (m_end - m_init);
158 }
159 
163 claw::tween::single_tweener* claw::tween::single_tweener::do_clone() const
164 {
165  return new single_tweener(*this);
166 }
167 
171 bool claw::tween::single_tweener::do_is_finished() const
172 {
173  return m_date >= m_duration;
174 }
175 
180 double claw::tween::single_tweener::do_update(double dt)
181 {
182  const double t(std::min(m_duration - m_date, dt));
183  const double result = dt - t;
184  m_date += t;
185 
186  const double val(get_value());
187 
188  if(m_callback)
189  m_callback(val);
190 
191  return result;
192 }
void set_init(double v)
Sets the initial value.
double get_end() const
Gets the final value.
A single_tweener makes a value to evolve through time from a initial value to an end value according ...
void set_duration(double v)
Sets the total duration.
std::function< void(double)> update_function
The type of the function called when the single_tweener is updated.
double get_value() const
Gets the current value of the tweener.
std::function< double(double)> easing_function
The type of the function used to compute the new value.
void set_callback(update_function f)
The function called when the single_tweener is updated.
void set_end(double v)
Sets the final value.
double get_duration() const
Gets the total duration.
single_tweener()
Default constructor.
A single_tweener makes a value to evolve through time from a initial value to an end value according ...
double get_init() const
Gets the initial value.
Easing functions for the tweener. Those functions do nothing.
Definition: easing_none.hpp:40
void set_easing(easing_function f)
The function used to compute the new value.