Merge pull request #64 from jr0dsgarage/fixScaleCorruption

Fix possible Scale Corruption in Midi Mode; disallow Lock and Group changes when scale is off

OMX-27-firmware/src/config.h

@@ -345,7 +345,9 @@ struct ScaleConfig
 	int scaleRoot = 0;
 	int scalePattern = -1;
 	bool lockScale = false; // If Scale is locked you will be unable to play notes out of the scale.
+	bool lockedState = false; // for holding previous scale lock state
 	bool group16 = false;	// If group16 is active, all notes in scale will be grouped into lower 16 notes.
+	bool groupedState = false;	// for holding previous group16 state
 	bool scaleSelectHold;
 	bool showScaleInSeq = false;
 };

OMX-27-firmware/src/modes/omx_mode_midi_keyboard.cpp

@@ -425,14 +425,39 @@ void OmxModeMidiKeyboard::onEncoderChanged(Encoder::Update enc)
 				omxDisp.displayMessage(musicScale->getScaleName(scaleConfig.scalePattern));
 				musicScale->calculateScale(scaleConfig.scaleRoot, scaleConfig.scalePattern);
 			}
+
+			if (scaleConfig.scalePattern == -1)
+			{ // record locked and grouped states, then set the current lockScale and group16 to off
+				if (prevPat != -1)
+				{
+					scaleConfig.lockedState = scaleConfig.lockScale;
+					scaleConfig.groupedState = scaleConfig.group16;
+				}
+				scaleConfig.lockScale = 0;
+				scaleConfig.group16 = 0;
+			}
+			else
+			{ // restore locked and grouped states if the scale was previously set to off
+				if (prevPat == -1)
+				{
+					scaleConfig.lockScale = scaleConfig.lockedState;
+					scaleConfig.group16 = scaleConfig.groupedState;
+				}
+			}
 		}
 		if (selParam == 3)
 		{
-			scaleConfig.lockScale = constrain(scaleConfig.lockScale + amt, 0, 1);
+			if (scaleConfig.scalePattern != -1)
+			{
+				scaleConfig.lockScale = constrain(scaleConfig.lockScale + amt, 0, 1);
+			}
 		}
 		if (selParam == 4)
 		{
-			scaleConfig.group16 = constrain(scaleConfig.group16 + amt, 0, 1);
+			if (scaleConfig.scalePattern != -1)
+			{
+				scaleConfig.group16 = constrain(scaleConfig.group16 + amt, 0, 1);
+			}
 		}
 	}
 	else if(selPage == MIPAGE_CFG)