-- Example 4 - Using Csound's Performance Thread

-- Author: Steven Yi <stevenyi@gmail.com>

-- 2013.10.28

--

-- In this example, we use a CsoundPerformanceThread to run Csound in

-- a native thread. Using a native thread is important to get the best

-- runtime performance for the audio engine. It is especially important

-- for languages such as Python that do not have true native threads

-- and that use a Global Interpreter Lock. CsoundPerformanceThread has

-- some convenient methods for handling events, but does not have

-- features for doing regular processing at block boundaries. In general,

-- use CsoundPerformanceThread when the only kinds of communication you

-- are doing with Csound are through events, and not using channels.

require "luaCsnd6"

-- from csnd6 import Csound, CsoundPerformanceThread

-- Our Orchestra for our project

local orc = [[

sr=44100

ksmps=32

nchnls=2

0dbfs=1

instr 1

aout vco2 0.5, 440

outs aout, aout

endin

]]

-- Our Score for our project

local sco = "i1 0 1"

local c = luaCsnd6.Csound() -- create an instance of Csound

c:SetOption("-odac") -- Set option for Csound

c:CompileOrc(orc) -- Compile Orchestra from String

c:ReadScore(sco) -- Read in Score from String

c:Start() -- When compiling from strings, this call is necessary before doing any performing

local t = luaCsnd6.CsoundPerformanceThread(c) -- Create a new CsoundPerformanceThread, passing in the Csound object

t:Play() -- starts the thread, which is now running separately from the main thread. This

-- call is asynchronous and will immediately return back here to continue code

-- execution.

t:Join() -- Join will wait for the other thread to complete. If we did not call Join(),

-- after t.Play() returns we would immediate move to the next line, c.Stop().

-- That would stop Csound without really giving it time to run.

c:Stop() -- stops Csound

c:Cleanup() -- clean up Csound; this is useful if you're going to reuse a Csound instance