vu meter (re)added

esp-pixelbox.ino

@@ -77,6 +77,39 @@ bool onSetPixel(const HomieRange& range, const String& value) {
   homieNode.setProperty("pixel_" + String(range.index)).send(value);
 }
 
+bool onSetVU(const HomieRange& range, const String& value) {
+  strip.Stop(); // Do not show any "effects" anymore
+  strip.clear(); // All pixels to black
+  String remaining = value;
+  String current;
+  int i = 0;
+  do
+  {
+    if (remaining.length() == 1)
+    {
+      current = remaining.substring(0,1);
+    } else {
+      current = remaining.substring(0,2);
+    }
+    int currentvalue = (int) strtol(&current[0], NULL, 10);
+    // White peak
+    strip.setPixelColor(strip.numToPos(56+i-currentvalue*8), 16777215); // White dot
+    // Shaded bar "below" the peak
+    if (currentvalue>0)
+    {
+      for (int j=currentvalue-1;j>-1;j--)
+      {
+        strip.setPixelColor(strip.numToPos(56+i-j*8), 4276545); // Greyscale
+      }
+    }
+    i++;
+    remaining = remaining.substring(2);
+  } while (remaining.length()>0); // TODO: Not bigger than strip
+  strip.show();
+  homieNode.setProperty("VU_" + String(range.index)).send(value);
+}
+
+
 bool onSetBrightness(const HomieRange& range, const String& value) {
   long brightness = value.toInt();
   if (brightness < 0 || brightness > 255) {
@@ -320,7 +353,7 @@ void setup() {
   homieNode.advertise("icon").settable(onSetIcon);
   homieNode.advertise("next").settable(onSetNext);
   homieNode.advertiseRange("pixels", 0, (NUMPIXELS - 1) * 7).settable(onSetPixels);
-
+  homieNode.advertiseRange("vu", 0, sqrt(NUMPIXELS)-1).settable(onSetVU);
 
   strip.begin();
   strip.clear();