POKEY music

src/audio.js

@@ -191,16 +191,16 @@ var POKEYDeviceChannel = function() {
         if (d > 0 && d < 1 && v > 0) {
           var wav = waveforms[i];
           var cnt = counters[i] += d;
-          if (cnt > POLY17_SIZE+1) {
-            counters[i] -= POLY17_SIZE+1;
+          if (cnt > wav.length) {
+            cnt = counters[i] = cnt - Math.floor(cnt / wav.length) * wav.length;
           }
-          var on = wav[Math.floor(cnt % wav.length)];
+          var on = wav[Math.floor(cnt)];
           if (on) {
             sample += v;
           }
         }
       }
-      sample *= 273;
+      sample *= 128;
       buffer[s] = sample;
       buffer[s+1] = sample;
     }

src/platform/vector.js

@@ -7,6 +7,7 @@ var VECTOR_PRESETS = [
   {id:'font.c', name:'Vector Fonts'},
   {id:'threed.c', name:'3D Transformations'},
   {id:'game.c', name:'Space Game'},
+  {id:'music.c', name:'POKEY Music'},
 ]
 
 var ASTEROIDS_KEYCODE_MAP = makeKeycodeMap([

tools/mknotes.py

@@ -12,6 +12,7 @@ args = parser.parse_args()
 test_notes = args.upper
 final_notes = args.length
 basehz = args.freq
+bias = args.bias
 
 results = []
 
@@ -19,7 +20,7 @@ for a440 in range(4300,4500):
     error = 0
     for note in range(1,test_notes):
         notehz = a440 / 10.0 * math.pow(2.0, (note - 49) / 12.0);
-        period = int(round(basehz / notehz))
+        period = int(round(basehz / notehz)) 
         tonehz = basehz / period
         error += abs(notehz-tonehz)
         #print a440,note,notehz,notehz-tonehz,period
@@ -35,6 +36,6 @@ print '//', best_a440, best_error, test_notes
 print "const int note_table[%d] = {" % final_notes
 for note in range(0,final_notes):
     notehz = best_a440 * math.pow(2.0, (note - 49) / 12.0);
-    period = int(round(basehz / notehz))
+    period = int(round(basehz / notehz)) - bias
     print '%d,' % period,
 print "};"