1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
|
/*
Rosegarden
A sequencer and musical notation editor.
This program is Copyright 2000-2008
Guillaume Laurent <[email protected]>,
Chris Cannam <[email protected]>,
Richard Bown <[email protected]>
The moral right of the authors to claim authorship of this work
has been asserted.
This program 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. See the file
COPYING included with this distribution for more information.
*/
#ifndef _RULER_SCALE_H_
#define _RULER_SCALE_H_
#include "Event.h"
namespace Rosegarden {
class Composition;
/**
* RulerScale is a base for classes that may be queried in order to
* discover the correct x-coordinates for bar lines and bar
* subdivisions.
*
* RulerScale does not contain any methods that relate bar numbers
* to times, time signature or duration -- those are in Composition.
*
* The methods in RulerScale should return extrapolated (but valid)
* results even when passed a bar number outside the theoretically
* visible or existant bar range.
*
* Apart from getBarPosition, every method in this class has a
* default implementation, which should work correctly provided
* the subclass maintains spacing proportional to time within a
* bar, but which may not be an efficient implementation for any
* given subclass.
*
* (Potential to-do: At the moment all our RulerScales are used in
* contexts where spacing proportional to time within a bar is the
* only interpretation that makes sense, so this is okay. In
* theory though we should probably subclass out these "default"
* implementations into an intermediate abstract class.)
*/
class RulerScale
{
public:
virtual ~RulerScale();
Composition *getComposition() const { return m_composition; }
/**
* Return the number of the first visible bar.
*/
virtual int getFirstVisibleBar() const;
/**
* Return the number of the last visible bar. (The last
* visible bar_line_ will be at the end of this bar.)
*/
virtual int getLastVisibleBar() const;
/**
* Return the x-coordinate at which bar number n starts.
*/
virtual double getBarPosition(int n) const = 0;
/**
* Return the width of bar number n.
*/
virtual double getBarWidth(int n) const;
/**
* Return the width of each beat subdivision in bar n.
*/
virtual double getBeatWidth(int n) const;
/**
* Return the number of the bar containing the given x-coord.
*/
virtual int getBarForX(double x) const;
/**
* Return the nearest time value to the given x-coord.
*/
virtual timeT getTimeForX(double x) const;
/**
* Return the x-coord corresponding to the given time value.
*/
virtual double getXForTime(timeT time) const;
/**
* Return the duration corresponding to the given delta-x
* starting at the given x-coord.
*/
virtual timeT getDurationForWidth(double x, double width) const;
/**
* Return the width corresponding to the given duration
* starting at the given time.
*/
virtual double getWidthForDuration(timeT startTime, timeT duration) const;
/**
* Return the width of the entire scale.
*/
virtual double getTotalWidth() const;
protected:
RulerScale(Composition *c);
Composition *m_composition;
};
/**
* SimpleRulerScale is an implementation of RulerScale that maintains
* a strict proportional correspondence between x-coordinate and time.
*/
class SimpleRulerScale : public RulerScale
{
public:
/**
* Construct a SimpleRulerScale for the given Composition, with a
* given origin and x-coord/time ratio. (For example, a ratio of
* 10 means that one pixel equals 10 time units.)
*/
SimpleRulerScale(Composition *composition,
double origin, double unitsPerPixel);
virtual ~SimpleRulerScale();
double getOrigin() const { return m_origin; }
void setOrigin(double origin) { m_origin = origin; }
double getUnitsPerPixel() const { return m_ratio; }
void setUnitsPerPixel(double ratio) { m_ratio = ratio; }
virtual double getBarPosition(int n) const;
virtual double getBarWidth(int n) const;
virtual double getBeatWidth(int n) const;
virtual int getBarForX(double x) const;
virtual timeT getTimeForX(double x) const;
virtual double getXForTime(timeT time) const;
protected:
double m_origin;
double m_ratio;
private:
SimpleRulerScale(const SimpleRulerScale &ruler);
SimpleRulerScale &operator=(const SimpleRulerScale &ruler);
};
}
#endif
|
