handle disconnected Scale inpput

CHANGELOG.md

@@ -3,6 +3,7 @@
 ## 2.7.0-beta2
 
 * Changed Harp output polyphony to 16 channels (was only 5 in beta1).
+* Handled unconnected Scale input in Harp - treat as a chromatic scale rooted at C4. 
 
 ## 2.7.0-beta1
 

README.md

@@ -371,7 +371,7 @@ This is that specialized software.
 
 Inputs:
 
-* **Scale** - Defines the notes of the scale to be strummed (V/Oct, polyphonic).  Channel 0 is treated as the "root" of the strum range.   The expected format is compatible with docB's Gen Scale and Aaron Static's ScaleCV modules.
+* **Scale** - Defines the notes of the scale to be strummed (V/Oct, polyphonic).  Channel 0 is treated as the "root" of the strum range.   The expected format is compatible with docB's Gen Scale and Aaron Static's ScaleCV modules.  If unconnected, the Harp uses a chromatic scale rooted at C4. 
 
 * **Pitch** - The CV signal from the control surface. Not V/Oct; just a continous range of voltage that corresponds to where the musicians fingers are touching the control surface.  Valid voltage range is determined by context menu (see below).
 

src/Harp.cpp

@@ -78,10 +78,22 @@ namespace Harp {
 		 auto inputCvMin = MIDIRecorder::CVRanges[cvConfigPitch].low;
 		 auto inputCvMax = MIDIRecorder::CVRanges[cvConfigPitch].high;
 		 int s = std::round((v - inputCvMin) / (inputCvMax - inputCvMin) * (noteRange-1));
-		 int degree = s % inputs[SCALE_INPUT].getChannels();
-		 int octave = s / inputs[SCALE_INPUT].getChannels();
+		 float scaledPitch;
+		 int scaleSize = 11; // default to chromatic
+		 if (inputs[SCALE_INPUT].isConnected()) {
+		     scaleSize = inputs[SCALE_INPUT].getChannels();
+		     scaledPitch = inputs[SCALE_INPUT].getPolyVoltage(degree);
+		 }
+		 int degree = s % scaleSize;
+	         int octave = s / scaleSize;
+		 if (! inputs[SCALE_INPUT].isConnected()) {
+		     // default is chromatic with root at C4
+		     const float C4 = 0.0f;
+		     const float SEMITONE = 1.0f/12.f;
+		     scaledPitch = C4 + (degree * SEMITONE);
+		 }
 		 //INFO("note: r:%d pi:%d s:%d d:%d o:%d",noteRange, cvConfigPitch,s,degree,octave);
-		 currNote = inputs[SCALE_INPUT].getPolyVoltage(degree) + (octave * 1.f);
+		 currNote = scaledPitch + (octave * 1.f);
 	    }
 
 	    if (notePlaying) {