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* NKSP: Added built-in functions get_event_par() and set_event_par().
* NKSP: Added built-in constants $EVENT_PAR_NOTE, $EVENT_PAR_TUNE,
  $EVENT_PAR_VELOCITY, $EVENT_PAR_VOLUME and $EVENT_PAR_0 to $EVENT_PAR_3.

1 <html>
2 <head>
3 <meta name="author" content="Christian Schoenebeck">
4 <title>event_status() function</title>
5 <meta name="description" content="Returns the current status of a note.">
6 </head>
7 <body>
8 <h1>event_status()</h1>
9 <p>
10 Checks and returns the current status of the requested note. You can use
11 this function to check if a note is still "alive". A note is considered
12 "alive" as long as there are still active voices associated with it, which
13 might for example still be the case even long time after the respective
14 note's key had been released by the musician (i.e. because the voice uses
15 a very long release envelope stage).
16 </p>
17 <p>
18 If you are rather just interested whether a certain note key is currently
19 pressed down, then you can read the built-in array variable
20 <code lang="nksp">%KEY_DOWN[]</code> instead.
21 </p>
22
23 <h3>Function Prototype</h3>
24 <p/>
25 <code lang="nksp">
26 event_status(??note??)
27 </code>
28
29 <h3>Arguments</h3>
30 <table>
31 <tr>
32 <th>Argument Name</th> <th>Data Type</th> <th>Description</th>
33 </tr>
34 <tr>
35 <td><code>??note??</code></td>
36 <td>Note ID Number</td>
37 <td>Status of this note will be checked.<br>
38 [required]</td>
39 </tr>
40 </table>
41
42 <h3>Return Value</h3>
43 <p>
44 Returns either <code>$EVENT_STATUS_INACTIVE</code> if the requested note
45 is already dead and gone, or <code>$EVENT_STATUS_NOTE_QUEUE</code> if
46 the note is still alive.
47 </p>
48 <note>
49 Even though there are currently just two possible return values,
50 <code>$EVENT_STATUS_NOTE_QUEUE</code> is defined as bit flag though, and since
51 other bit flags might be added in future you should only compare bitwise with
52 <code>$EVENT_STATUS_NOTE_QUEUE</code>. See example below.
53 </note>
54
55 <h3>Examples</h3>
56 <p>
57 The following example shows a simple stuttering effect. The script
58 runs in an endless loop and turns down and up the volume all 200ms.
59 To stop the endless loop once the respective note died, the return
60 value of <code>event_status()</code> is compared with built-in constant
61 bit flag <code>$EVENT_STATUS_INACTIVE</code>.
62 </p>
63 <code>
64 on note
65 while (1)
66 wait(200000)
67 if (event_status($EVENT_ID) = $EVENT_STATUS_INACTIVE)
68 exit() { note is no longer alive, so stop script here }
69 end if
70 change_vol($EVENT_ID, -20000) { Reduce volume by 20 dB. }
71
72 wait(200000)
73 if (event_status($EVENT_ID) = $EVENT_STATUS_INACTIVE)
74 exit() { note is no longer alive, so stop script here }
75 end if
76 change_vol($EVENT_ID, 0) { Increase volume to 0 dB. }
77 end while
78 end on
79 </code>
80 <p>
81 Note: since the built-in constants returned by this function are actually bit flags,
82 and since further bit flags might be added in future for this function, the actual
83 long-term safe and correct way to check the return value of <code>event_status()</code>
84 is a bitwise comparison. So the recommended "correct" way for the example above would
85 actually be:
86 </p>
87 <code>
88 on note
89 while (1)
90 wait(200000)
91 if (not (event_status($EVENT_ID) .and. $EVENT_STATUS_NOTE_QUEUE))
92 exit() { note is no longer alive, so stop script here }
93 end if
94 change_vol($EVENT_ID, -20000) { Reduce volume by 20 dB. }
95
96 wait(200000)
97 if (not (event_status($EVENT_ID) .and. $EVENT_STATUS_NOTE_QUEUE))
98 exit() { note is no longer alive, so stop script here }
99 end if
100 change_vol($EVENT_ID, 0) { Increase volume to 0 dB. }
101 end while
102 end on
103 </code>
104 <p>
105 In practice however, the first version of this example is much easier to
106 read (and write) though, and new bit flags will probably not be added to
107 this function in near future. But that's up to you to decide!
108 </p>
109
110 <h3>Availabilty</h3>
111 <p>Since LinuxSampler 2.0.0.svn12.<p>
112
113 <note>
114 LinuxSampler does currently not support KSP's <code>$EVENT_STATUS_MIDI_QUEUE</code> flag as return value.
115 </note>
116
117 </body>
118 </html>

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