wip: rewrite and cleanup

static/qrplay/v3b.min.html

@@ -0,0 +1,102 @@
+<META NAME=VIEWPORT CONTENT=INITIAL=SCALE=1>
+<CENTER>
+<P><A HREF=http://nycki.net/qrplay>qrplay v3b</A></P>
+<TEXTAREA ID=F STYLE=WIDTH:MIN(40EM,99%);HEIGHT:9LH>; drum samples!
+i 0000 1111 2222 4444 5555 6666 7777 8888 9999
+
+hx@
+
+; you can overwrite samples
+0[-c+c]
+00000000
+
+hx@
+
+; state is NOT preserved when playing samples
+0[cdefgab+]
+0000
+
+; state IS preserved during parallel play
+@q {-ggeec}
+     cdefg
+  
+hx@
+
+; infinite loop
+0[i9x9x6xxx0]
+0
+</textarea><p>
+<button onclick="
+F.A?.close();
+F.A=A=new AudioContext;
+S='@'+F.value;
+// stack
+B=[];
+// stack variables
+K=O=T=Z=L=0;
+U=137;
+V=40;
+// samples
+C=[];
+
+// main loop
+M=()=>{
+	[a,b,c]=S;
+	// next index into S
+	s=1;
+	// opcode
+	z='\n;+-@.3cdefgabx012456789jtsiqhwmuvo{}'.indexOf(a);
+
+	// no match
+	z<0?0:
+
+	// comment
+	z<2?K=z:K?0:
+	
+	// octave
+	z<4?O+=a+1|0:
+	
+	// reset octave and length
+	z<5?(O=0,L=1):
+	
+	// dots and triplets
+	z<6?L*=3/2:
+	z<7?L/=3:
+
+	// note or rest
+	z<13?(
+		z-=7,
+		o=new OscillatorNode(A,{
+			type:'square',
+			detune:100*(z*2-(z>2)-(b=='!')+(b=='#')+12*O-9)
+		}),
+		g=new GainNode(A,{gain:z<7&&.5**(12-V/5)}),
+		o.connect(g),
+		g.connect(A.destination),
+		o.start(T),
+		o.stop(T+=7.5*L/U)
+	):
+	
+	// store sample
+	z<22&&b=='['?(
+		m=0,
+		d=B.findIndex.call(S,c=>
+			c=='['?!++m:
+			c==']'?!--m:
+			0
+		),
+		C[a]=S.slice(s,d),
+		s=d+1
+	):
+
+	// play sample
+	z<22?S=C[a]+S.slice(s):
+
+	// do nothing
+	0;
+	
+	// loop
+	S=S.slice(s);
+	S&&setTimeout(M)
+};M()
+">#play</BUTTON>