update examples to use math.randomstate

examples/assets/hihat.lua

@@ -1,24 +1,28 @@
-math.randomseed(0x12345)
-
 return rhythm {
   unit = "1/8",
   pattern = function(context)
-    if math.imod(context.pulse_step, 8) == 1 then
-      return { 0.8, 0.2, 0.9, 0.2 }
-    else
-      if math.random() > 0.9 then
-        return { 0.8, 0.9 }
-      else 
-        return { 1 }
+    local rand = math.randomstate(0x12345)
+    return function(context)
+      if math.imod(context.pulse_step, 8) == 1 then
+        return { 0.8, 0.2, 0.9, 0.2 }
+      else
+        if rand() > 0.9 then
+          return { 0.8, 0.9 }
+        else
+          return { 1 }
+        end
       end
     end
   end,
   emit = function(context)
-    local note = "c6"
-    local _, fraction = math.modf(context.pulse_time_step)
-    if fraction == 1.0/2.0 then
-      note = "c5 v0.3"
+    local rand = math.randomstate(0x8879)
+    return function(context)
+      local note = rand(1, 10) >= 8 and "c6" or "c7"
+      local _, fraction = math.modf(context.pulse_time_step)
+      if fraction == 1.0 / 2.0 then
+        note = "c5 v0.3"
+      end
+      return note
     end
-    return note
   end
-}
+}