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<html> |
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<head> |
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<meta name="author" content="Christian Schoenebeck"> |
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<title>event_status() function</title> |
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<meta name="description" content="Returns the current status of a note."> |
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</head> |
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<body> |
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<h1>event_status()</h1> |
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<p> |
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Checks and returns the current status of the requested note. You can use |
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this function to check if a note is still "alive". A note is considered |
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"alive" as long as there are still active voices associated with it, which |
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might for example still be the case even long time after the respective |
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note's key had been released by the musician (i.e. because the voice uses |
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a very long release envelope stage). |
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</p> |
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<p> |
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If you are rather just interested whether a certain note key is currently |
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pressed down, then you can read the built-in array variable |
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<code lang="nksp">%KEY_DOWN[]</code> instead. |
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</p> |
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|
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<h3>Function Prototype</h3> |
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<p/> |
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<code lang="nksp"> |
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event_status(??note??) |
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</code> |
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|
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<h3>Arguments</h3> |
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<table> |
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<tr> |
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<th>Argument Name</th> <th>Data Type</th> <th>Description</th> |
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</tr> |
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<tr> |
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<td><code>??note??</code></td> |
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<td>Note ID Number</td> |
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<td>Status of this note will be checked.<br> |
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[required]</td> |
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</tr> |
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</table> |
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|
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<h3>Return Value</h3> |
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<p> |
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Returns either <code>$EVENT_STATUS_INACTIVE</code> if the requested note |
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is already dead and gone, or <code>$EVENT_STATUS_NOTE_QUEUE</code> if |
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the note is still alive. |
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</p> |
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<note> |
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Even though there are currently just two possible return values, |
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<code>$EVENT_STATUS_NOTE_QUEUE</code> is defined as bit flag though, and since |
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other bit flags might be added in future you should only compare bitwise with |
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<code>$EVENT_STATUS_NOTE_QUEUE</code>. See example below. |
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</note> |
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|
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<h3>Examples</h3> |
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<p> |
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The following example shows a simple stuttering effect. The script |
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runs in an endless loop and turns down and up the volume all 200ms. |
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To stop the endless loop once the respective note died, the return |
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value of <code>event_status()</code> is compared with built-in constant |
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bit flag <code>$EVENT_STATUS_INACTIVE</code>. |
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</p> |
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<code> |
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on note |
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while (1) |
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wait(200000) |
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if (event_status($EVENT_ID) = $EVENT_STATUS_INACTIVE) |
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exit() { note is no longer alive, so stop script here } |
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end if |
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change_vol($EVENT_ID, -20000) { Reduce volume by 20 dB. } |
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|
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wait(200000) |
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if (event_status($EVENT_ID) = $EVENT_STATUS_INACTIVE) |
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exit() { note is no longer alive, so stop script here } |
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end if |
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change_vol($EVENT_ID, 0) { Increase volume to 0 dB. } |
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end while |
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end on |
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</code> |
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<p> |
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Note: since the built-in constants returned by this function are actually bit flags, |
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and since further bit flags might be added in future for this function, the actual |
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long-term safe and correct way to check the return value of <code>event_status()</code> |
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is a bitwise comparison. So the recommended "correct" way for the example above would |
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actually be: |
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</p> |
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<code> |
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on note |
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while (1) |
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wait(200000) |
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if (not (event_status($EVENT_ID) .and. $EVENT_STATUS_NOTE_QUEUE)) |
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exit() { note is no longer alive, so stop script here } |
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end if |
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change_vol($EVENT_ID, -20000) { Reduce volume by 20 dB. } |
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|
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wait(200000) |
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if (not (event_status($EVENT_ID) .and. $EVENT_STATUS_NOTE_QUEUE)) |
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exit() { note is no longer alive, so stop script here } |
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end if |
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change_vol($EVENT_ID, 0) { Increase volume to 0 dB. } |
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end while |
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end on |
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</code> |
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<p> |
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In practice however, the first version of this example is much easier to |
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read (and write) though, and new bit flags will probably not be added to |
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this function in near future. But that's up to you to decide! |
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</p> |
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|
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<h3>Availability</h3> |
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<p>Since LinuxSampler 2.0.0.svn12.<p> |
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|
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<h3>See also</h3> |
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<p><code>callback_status()</code><p> |
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|
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<note> |
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LinuxSampler does currently not support KSP's <code>$EVENT_STATUS_MIDI_QUEUE</code> flag as return value. |
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</note> |
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|
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</body> |
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</html> |