1 |
/* |
2 |
Copyright (C) 2008 Christian Schoenebeck |
3 |
*/ |
4 |
|
5 |
#ifndef LS_VIRTUALMIDIDEVICE_H |
6 |
#define LS_VIRTUALMIDIDEVICE_H |
7 |
|
8 |
#include "../../common/global.h" |
9 |
|
10 |
namespace LinuxSampler { |
11 |
|
12 |
/** |
13 |
* Light-weight MIDI interface (for MIDI in & out) intended to be used by |
14 |
* pure software MIDI "devices", that is e.g. a graphical virtual MIDI |
15 |
* keyboard in an instrument editor or in a sampler frontend. This class |
16 |
* should not be used for regular MIDI input device drivers for the sampler. |
17 |
* This primitive interface by design doesn't care about jitter, fast event |
18 |
* delivery or masses and masses of events in a short time! |
19 |
*/ |
20 |
class VirtualMidiDevice { |
21 |
public: |
22 |
enum event_type_t { |
23 |
EVENT_TYPE_NOTEON = 1, |
24 |
EVENT_TYPE_NOTEOFF = 2 |
25 |
}; |
26 |
|
27 |
struct event_t { |
28 |
event_type_t Type; |
29 |
uint8_t Key; |
30 |
uint8_t Velocity; |
31 |
}; |
32 |
|
33 |
///////////////////////////////////////////////////////////////// |
34 |
// Device methods |
35 |
// (called by the VirtualMidiDevice implementation) |
36 |
|
37 |
/** |
38 |
* Sends a MIDI @e note @e on event to the sampler. |
39 |
* |
40 |
* @returns true on success, false if internal FIFO full |
41 |
* (or provided values invalid) |
42 |
*/ |
43 |
bool SendNoteOnToSampler(uint8_t Key, uint8_t Velocity); |
44 |
|
45 |
/** |
46 |
* Sends a MIDI @e note @e off event to the sampler. |
47 |
* |
48 |
* @returns true on success, false if internal FIFO full |
49 |
* (or provided values invalid) |
50 |
*/ |
51 |
bool SendNoteOffToSampler(uint8_t Key, uint8_t Velocity); |
52 |
|
53 |
/** |
54 |
* Can be called by the virtual MIDI device to check whether a new note |
55 |
* on or note off MIDI event arrived to the sampler during the last |
56 |
* call to this method. So this is a asynchronously, "polling" based |
57 |
* communication mechanism, which works in conjunction with the |
58 |
* NoteIsActive() method call. |
59 |
*/ |
60 |
bool NotesChanged(); |
61 |
|
62 |
/** |
63 |
* Can be called by the virtual MIDI device to check whether a new note |
64 |
* on or note off MIDI event arrived to the sampler for @a Key during |
65 |
* the last call to this method. So this is a asynchronously, |
66 |
* "polling" based communication mechanism, which works in |
67 |
* conjunction with the NoteIsActive() method call. |
68 |
*/ |
69 |
bool NoteChanged(uint8_t Key); |
70 |
|
71 |
/** |
72 |
* Can be called by the virtual MIDI device to check which key / note |
73 |
* is currently active by the sampler, e.g. to highlight the |
74 |
* respective keys on a graphical virtual keyboard. |
75 |
* |
76 |
* @see NotesChanged(), NoteChanged() |
77 |
*/ |
78 |
bool NoteIsActive(uint8_t Key); |
79 |
|
80 |
/** |
81 |
* Returns the velocity of the @e last note on event. No FIFO is used! |
82 |
*/ |
83 |
uint8_t NoteOnVelocity(uint8_t Key); |
84 |
|
85 |
/** |
86 |
* Returns the velocity of the @e last note off event. No FIFO is used! |
87 |
*/ |
88 |
uint8_t NoteOffVelocity(uint8_t Key); |
89 |
|
90 |
///////////////////////////////////////////////////////////////// |
91 |
// Sampler methods |
92 |
// (usually only called by the Sampler) |
93 |
|
94 |
/** |
95 |
* Informs the virtual MIDI device that a @e note @e on event occured |
96 |
* (e.g. caused by a MIDI keyboard connected to the sampler). |
97 |
* Communication acts asynchronously, that is this method call doesn't |
98 |
* lock in any way and returns immediately. It is thus realtime safe. |
99 |
* |
100 |
* @e Note: this method is usually only called by the sampler. |
101 |
* |
102 |
* @see ActiveNotesChanged(), NoteIsActive() |
103 |
*/ |
104 |
void SendNoteOnToDevice(uint8_t Key, uint8_t Velocity); |
105 |
|
106 |
/** |
107 |
* Informs the virtual MIDI device that a @e note @e off event occured |
108 |
* (e.g. caused by a MIDI keyboard connected to the sampler). |
109 |
* Communication acts asynchronously, that is this method call doesn't |
110 |
* lock in any way and returns immediately. It is thus realtime safe. |
111 |
* |
112 |
* @e Note: this method is usually only called by the sampler. |
113 |
* |
114 |
* @see ActiveNotesChanged(), NoteIsActive() |
115 |
*/ |
116 |
void SendNoteOffToDevice(uint8_t Key, uint8_t Velocity); |
117 |
|
118 |
/** |
119 |
* Gets the next pending MIDI event from the virtual MIDI device by |
120 |
* using a lockfree FIFO. |
121 |
* |
122 |
* @e Note: this method is usually only called by the sampler. |
123 |
* |
124 |
* @param Event - destination for writing the next event to |
125 |
* @returns true on success, false if no event pending |
126 |
*/ |
127 |
bool GetMidiEventFromDevice(event_t& Event); |
128 |
|
129 |
/** |
130 |
* Constructor |
131 |
*/ |
132 |
VirtualMidiDevice(); |
133 |
|
134 |
/** |
135 |
* Destructor |
136 |
*/ |
137 |
virtual ~VirtualMidiDevice(); |
138 |
|
139 |
private: |
140 |
struct private_data_t; |
141 |
private_data_t* const p; |
142 |
}; |
143 |
|
144 |
} // namespace LinuxSampler |
145 |
|
146 |
#endif // LS_VIRTUALMIDIDEVICE_H |