Add further examples

Author: ideoforms

examples/buffer-read.py

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+#!/usr/bin/env python3 
+
+"""
+Example: Read and play an audio file.
+
+Before running this script, the SC server must be started, and the following
+SynthDef stored:
+
+SynthDef(\playbuf, { |out = 0, bufnum = 0, gain = 0.0|
+    var data = PlayBuf.ar(1, bufnum, loop: 1) * gain.dbamp;
+    Out.ar(out, Pan2.ar(data));
+}).store;
+
+You will also need to download some sample audio:
+curl https://nssdc.gsfc.nasa.gov/planetary/sound/apollo_13_problem.wav -o apollo.wav
+"""
+
+AUDIO_FILE = "apollo.wav"
+
+from supercollider import Server, Synth, Buffer
+import time
+
+#-------------------------------------------------------------------------------
+# Create connection to default server on localhost:57110
+#-------------------------------------------------------------------------------
+server = Server()
+
+#-------------------------------------------------------------------------------
+# Read sample data into a Buffer.
+#-------------------------------------------------------------------------------
+buf = Buffer.read(server, AUDIO_FILE)
+buf_info = buf.info
+print("Read buffer, sample rate %d, duration %.1fs" % (buf_info["sample_rate"], buf_info["num_frames"] / buf_info["sample_rate"]))
+
+#-------------------------------------------------------------------------------
+# Calculate the required playback rate (akin to SC BufRateScale.kr)
+# and begin playback.
+#-------------------------------------------------------------------------------
+server_sample_rate = server.status["sample_rate_nominal"]
+buffer_sample_rate = buf_info["sample_rate"]
+rate = buffer_sample_rate / server_sample_rate
+synth = Synth(server, 'playbuf', { "buffer" : buf, "rate": rate })
+
+try:
+    while True:
+        time.sleep(0.1)
+except KeyboardInterrupt:
+    synth.free()
+    buf.free()

examples/buffer-write.py

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+#!/usr/bin/env python3 
+
+"""
+Example: Write the contents of a Buffer to disk.
+"""
+
+from supercollider import Server, Synth, Buffer, HEADER_FORMAT_WAV
+import math
+
+OUTPUT_FILE = "/tmp/440.wav"
+
+#-------------------------------------------------------------------------------
+# Create connection to default server on localhost:57110
+#-------------------------------------------------------------------------------
+server = Server()
+
+#-------------------------------------------------------------------------------
+# Create a Buffer, generate a 440Hz sine, and write to a .wav.
+#-------------------------------------------------------------------------------
+length = 1024
+buf = Buffer.alloc(server, length)
+buf.set([ math.sin(n * math.pi * 2.0 * 440.0 / sample_rate) for n in range(int(length)) ])
+buf.write(OUTPUT_FILE, HEADER_FORMAT_WAV)

examples/bus-example.py

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+#!/usr/bin/env python3 
+
+"""
+Example: Audio routing with buses.
+
+Before running this script, the SC server must be started, and the following
+SynthDefs stored:
+
+SynthDef(\dust, { |out = 0, gain = 0.0|
+	var data = Dust.ar(10) * gain.dbamp;
+	Out.ar(out, Pan2.ar(data));
+}).store;
+
+SynthDef(\reverb, { |in = 0, out = 2|
+	var data = In.ar(in, 2);
+	data = FreeVerb.ar(data, 0.7, 0.8, 0.5);
+	Out.ar(out, data);
+}).store;
+"""
+
+from supercollider import Server, Synth, Buffer, AudioBus, ADD_TO_TAIL
+
+import time
+
+#-------------------------------------------------------------------------------
+# Create connection to default server on localhost:57110
+#-------------------------------------------------------------------------------
+server = Server()
+
+#-------------------------------------------------------------------------------
+# Create a Buffer, read and play a sample.
+#-------------------------------------------------------------------------------
+bus = AudioBus(server, 2)
+synth = Synth(server, 'dust', { "out": bus })
+reverb = Synth(server, 'reverb', { "in": bus, "out": 0 }, target=server, action=ADD_TO_TAIL)
+
+try:
+    while True:
+        time.sleep(0.1)
+except KeyboardInterrupt:
+    bus.free()
+    synth.free()
+    reverb.free()