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dssictls

Writes a value to a plugin control input port.

These opcodes require the optional dssi4cs module on Linux. See DSSI and LADSPA plugins for build requirements and setup.

Syntax

dssictls(ihandle, iport, kvalue, ktrigger)

dssictls ihandle, iport, kvalue, ktrigger

Initialization

ihandle is the instance handle returned by dssiinit.

iport is a fixed, zero-based port number from the plugin's full port list. Audio ports count in this numbering too. Use the numbers printed by verbose dssiinit, and select a control input port. Do not use an audio port or an output port.

Performance

kvalue is the value to send. Use the plugin's units and allowed range. The opcode does not clamp values, round integer controls or convert decibels.

ktrigger must equal 1 to write the value. A constant 1 updates the control every cycle. Any other value leaves the stored control unchanged. This is a level test, not a rising-edge trigger.

For a port with the LADSPA sample-rate hint, the opcode multiplies kvalue by the sample rate before storing it. For example, a frequency of 440 Hz needs 440 / sr on such a port. Consult the plugin's range hints for these units.

Place control updates before dssiaudio to use them in the same control cycle. Set each required control explicitly before the first audio block. The opcode has no output and does not read control output ports.

Examples

The example changes the SDK mono amplifier gain from 0 to 1 over four seconds. Port 0 is its gain control. A constant trigger of 1 sends each new value. It requires amp.so and the Linux setup.

dssictls example
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<CsoundSynthesizer>
<CsOptions>
-odac -d
</CsOptions>
<CsInstruments>
sr = 48000
ksmps = 32
nchnls = 2
0dbfs = 1

giHandle = dssiinit("/usr/lib/ladspa/amp.so", 0, 1)

instr 1
  kGain = linseg(0, 4, 1, 2, 1)
  dssictls(giHandle, 0, kGain, 1)
  dssiactivate(giHandle, 1)
  aInput = oscili(0.1, 440)
  aOutput = dssiaudio(giHandle, aInput)
  out(aOutput, aOutput)
endin
</CsInstruments>
<CsScore>
i 1 0 6
e
</CsScore>
</CsoundSynthesizer>

See also

dssiinit, dssiactivate, dssictls, dssiaudio, dssilist, DSSI and LADSPA plugins

Credits

Author Andres Cabrera, 2005. Uses code from Richard Furse's LADSPA SDK.