use enum for readability, fixes, tweaks, new chip cases

src/gui/guiConst.h

@@ -19,6 +19,27 @@
 
 // guiConst: constants used in the GUI like arrays, strings and other stuff
 
+enum FurnaceGUIChanTypes {
+  // the first five match DivChanTypes, do not change order!
+
+  CHANNEL_TYPE_FM,
+  CHANNEL_TYPE_PULSE,
+  CHANNEL_TYPE_NOISE,
+  CHANNEL_TYPE_WAVETABLE,
+  CHANNEL_TYPE_SAMPLE, 
+
+  CHANNEL_TYPE_SQUARE,
+  CHANNEL_TYPE_TRIANGLE,
+  CHANNEL_TYPE_SAW,
+  CHANNEL_TYPE_OPERATOR,
+  CHANNEL_TYPE_DRUMS,
+  CHANNEL_TYPE_SLOPE,
+  CHANNEL_TYPE_WAVE,
+  CHANNEL_TYPE_OTHER,
+
+  CHANNEL_TYPE_MAX
+};
+
 struct FurnaceGUIActionDef {
   const char* name;
   const char* friendlyName;