add sequencer example

assets/.gitignore

@@ -1 +1,8 @@
-bitKlavierGrand_PianoBar
+bitKlavierGrand_PianoBar
+bass slide.wav
+Closed Hat.wav
+Crash2.wav
+House_Clap.wav
+kick.wav
+snare2.wav
+WaterDrop.wav

assets/sequencer.ck

@@ -0,0 +1,148 @@
+// number of tracks
+7 => int NUM_TRACKS;
+
+// TouchDesigner will set these global Event and int variables
+global Event notifier0;
+global Event notifier1;
+global Event notifier2;
+global Event notifier3;
+global Event notifier4;
+global Event notifier5;
+global Event notifier6;
+
+global int sequence0[4];
+global int sequence1[4];
+global int sequence2[4];
+global int sequence3[4];
+global int sequence4[8];
+global int sequence5[8];
+global int sequence6[16];
+
+// ChucK will own the following global variables,
+// and TouchDesigner will receive them in callbacks
+global float adsr_curves[NUM_TRACKS];
+
+// playheadPos loops between 0 and 1 every measure
+global float playheadPos;
+
+// Pick your own beats per minute.
+110. => float BPM;
+
+// Our video rate is 60 frames per second,
+// so we pick something less than (1000./60.)=16.6 ms
+10::ms => dur POS_RATE;
+
+// MEASURE_SEC is the amount of seconds in 4 quarter notes
+(240. / BPM)::second => dur MEASURE_SEC;
+
+// posInc is how much playheadPos needs to increment when now advances by POS_RATE
+POS_RATE/MEASURE_SEC => float posInc;
+
+class Track {
+
+    string myName;
+    int mySeq[];
+
+    SndBuf buf => Pan2 outlet;
+
+    0 => int trackID;
+
+    int previousZone;
+    float previousPlayhead;
+
+    -1 => previousZone;
+
+    Event myNotifier;
+
+    // ADSR adsr => blackhole;
+    // In order for the adsr to "cook",
+    // it needs something driving it,
+    // so we'll use a Step UGen whose value is set to 1.
+    Step step => ADSR adsr => blackhole;
+    1. => step.next;
+
+    .0625::second => dur minSustain;
+
+    time offTime;
+
+    fun void setup(int id, string name, string file_path, int seq[], Event notifier) {
+        id => trackID;
+        name => myName;
+        seq @=> mySeq;
+        me.dir() + file_path => buf.read;
+        0 => buf.pos;
+        0. => buf.rate;
+        notifier @=> myNotifier;
+
+        (62.5::ms, 20::ms, 1., 62.5::ms) => adsr.set;
+        0.2 => buf.gain;
+    }
+
+    fun void play() {
+
+        while (true) {
+
+            (playheadPos * mySeq.size()) $ int => int newZone;
+
+            if (newZone != previousZone || previousPlayhead > playheadPos) {
+                if (mySeq[newZone]) {
+                    // <<< "Note! " + myName>>>;
+                    now + minSustain => offTime;
+                    adsr.keyOn();
+                    0 => buf.pos;
+                    1. => buf.rate;
+                    myNotifier.broadcast();
+                }
+            }
+
+            if (now >= offTime) {
+                adsr.keyOff();
+            }
+
+            newZone => previousZone;
+            playheadPos => previousPlayhead;
+
+            adsr.last() => adsr_curves[trackID];
+
+            // <<< adsr.last() >>>;
+
+            POS_RATE => now;  
+        }
+    }
+}
+
+Track tracks[NUM_TRACKS];
+
+tracks[0].setup(0, "track0", "Crash2.wav",     sequence0, notifier0);
+tracks[1].setup(1, "track1", "House_Clap.wav", sequence1, notifier1);
+tracks[2].setup(2, "track2", "bass slide.wav", sequence2, notifier2);
+tracks[3].setup(3, "track3", "WaterDrop.wav",  sequence3, notifier3);
+tracks[4].setup(4, "track4", "kick.wav",       sequence4, notifier4);
+tracks[5].setup(5, "track5", "House_Clap.wav", sequence5, notifier5);
+tracks[6].setup(6, "track6", "Closed Hat.wav", sequence6, notifier6);
+
+Pan2 allTracks => dac;
+
+for (int i; i< NUM_TRACKS; i++) {
+    tracks[i].outlet => allTracks;
+    spork ~tracks[i].play();
+}
+
+// updates the global playheadPos with fine granularity,
+// for visualizing the playhead smoothly in TouchDesigner
+fun void playheadPosUpdate()
+{
+    while( true )
+    {
+        // increment
+        (playheadPos+posInc) % 1. => playheadPos;
+
+        // <<< playheadPos >>>;
+
+        // advance time
+        POS_RATE => now;
+    }
+}
+
+// this function will go forever
+playheadPosUpdate();