1 /* This file is part of Evoral.
2 * Copyright (C) 2008 Dave Robillard <http://drobilla.net>
3 * Copyright (C) 2000-2008 Paul Davis
5 * Evoral is free software; you can redistribute it and/or modify it under the
6 * terms of the GNU General Public License as published by the Free Software
7 * Foundation; either version 2 of the License, or (at your option) any later
10 * Evoral is distributed in the hope that it will be useful, but WITHOUT ANY
11 * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
12 * FOR A PARTICULAR PURPOSE. See the GNU General Public License for details.
14 * You should have received a copy of the GNU General Public License along
15 * with this program; if not, write to the Free Software Foundation, Inc.,
16 * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
19 #ifndef EVORAL_PARAMETER_HPP
20 #define EVORAL_PARAMETER_HPP
24 #include <boost/shared_ptr.hpp>
25 #include <boost/format.hpp>
31 /** ID of a [play|record|automate]able parameter.
33 * A parameter is defined by (type, id, channel). Type is an integer which
34 * can be used in any way by the application (e.g. cast to a custom enum,
35 * map to/from a URI, etc). ID is type specific (e.g. MIDI controller #).
37 * This class defines a < operator which is a strict weak ordering, so
38 * Parameter may be stored in a std::set, used as a std::map key, etc.
43 Parameter(uint32_t type, uint8_t channel=0, uint32_t id=0)
44 : _type(type), _id(id), _channel(channel)
47 virtual ~Parameter() {}
49 inline uint32_t type() const { return _type; }
50 inline uint32_t id() const { return _id; }
51 inline uint8_t channel() const { return _channel; }
53 /** Equivalence operator
54 * It is obvious from the definition that this operator
55 * is transitive, as required by stict weak ordering
56 * (see: http://www.sgi.com/tech/stl/StrictWeakOrdering.html)
58 inline bool operator==(const Parameter& id) const {
59 return (_type == id._type && _id == id._id && _channel == id._channel);
62 /** Strict weak ordering
63 * See: http://www.sgi.com/tech/stl/StrictWeakOrdering.html
64 * Sort Parameters first according to type then to id and lastly to channel.
68 * <li>Irreflexivity: f(x, x) is false because of the irreflexivity of \c < in each branch.</li>
69 * <li>Antisymmetry: given x != y, f(x, y) implies !f(y, x) because of the same
70 * property of \c < in each branch and the symmetry of operator==. </li>
71 * <li>Transitivity: let f(x, y) and f(y, z) be true.
72 * We prove by contradiction, assuming the contrary (f(x, z) is false).
73 * That would imply exactly one of the following:
75 * <li> x == z which contradicts the assumption f(x, y) and f(y, x)
76 * because of antisymmetry.
78 * <li> f(z, x) is true. That would imply that one of the ivars (we call it i)
79 * of x is greater than the same ivar in z while all "previous" ivars
80 * are equal. That would imply that also in y all those "previous"
81 * ivars are equal and because if x.i > z.i it is impossible
82 * that there is an y that satisfies x.i < y.i < z.i at the same
83 * time which contradicts the assumption.
85 * Therefore f(x, z) is true (transitivity)
90 inline bool operator<(const Parameter& id) const {
91 if (_type < id._type) {
93 } else if (_type == id._type && _id < id._id) {
95 } else if (_id == id._id && _channel < id._channel) {
102 inline operator bool() const { return (_type != 0); }
104 /** Not used in indentity/comparison */
106 Metadata(double low=0.0, double high=1.0, double mid=0.0)
107 : min(low), max(high), normal(mid)
114 inline static void set_range(uint32_t type, double min, double max, double normal) {
115 _type_metadata[type] = Metadata(min, max, normal);
118 inline void set_range(double min, double max, double normal) {
119 _metadata = boost::shared_ptr<Metadata>(new Metadata(min, max, normal));
122 inline Metadata& metadata() const {
124 return *_metadata.get();
126 return _type_metadata[_type];
129 inline double min() const { return metadata().min; }
130 inline double max() const { return metadata().max; }
131 inline double normal() const { return metadata().normal; }
134 // Default copy constructor is ok
136 // ID (used in comparison)
141 boost::shared_ptr<Metadata> _metadata;
143 typedef std::map<uint32_t, Metadata> TypeMetadata;
144 static TypeMetadata _type_metadata;
148 } // namespace Evoral
150 #endif // EVORAL_PARAMETER_HPP