More comment edits

1 files changed, 12 insertions, 9 deletions

diff --git a/macosx/tkMacOSXPrivate.h b/macosx/tkMacOSXPrivate.h
index 7903c6a..384a0df 100644
--- a/macosx/tkMacOSXPrivate.h
+++ b/macosx/tkMacOSXPrivate.h
@@ -129,13 +129,16 @@
 
 typedef struct keycode_v_t {
     unsigned keychar: 22;    /* UCS-32 character */
-    unsigned o_s: 2;         /* state of Option and Shift keys */
-    unsigned virtual: 8;     /* virtual keycode */
+    unsigned o_s: 2;         /* State of Option and Shift keys. */
+    unsigned virtual: 8;     /* 8-bit virtual keycode - identifies a key. */
 } keycode_v;
 
 typedef struct keycode_x_t {
     unsigned keychar: 22;     /* UCS-32 character */
-    unsigned xvirtual: 10;    /* lookup key for key maps */
+    unsigned xvirtual: 10;    /* Combines o_s and virtual. This 10-bit integer
+			       * is used as a key for looking up the character
+			       * produced when pressing a key with a particular
+			       * Shift and Option modifier state. */
 } keycode_x;
 
 typedef union MacKeycode_t {
@@ -150,7 +153,7 @@ typedef union MacKeycode_t {
  */
 
 #define ON_KEYPAD(virtual) ((virtual >= 0x41) && (virtual <= 0x5C))
-#define IS_PRINTABLE(keychar) ((keychar >= 0x20) && (keychar != 0x7f) &&\
+#define IS_PRINTABLE(keychar) ((keychar >= 0x20) && (keychar != 0x7f) && \
                                ((keychar < 0xF700) || keychar >= 0xF8FF))
 
 /*
@@ -169,17 +172,17 @@ typedef union MacKeycode_t {
 			    (state & Mod2Mask ? INDEX_OPTION : 0))
 
 /*
- * Special values for the virtual bitfield.
+ * Special values for the virtual bitfield.  Actual virtual keycodes are < 128.
  */
 
-#define NO_VIRTUAL 0xFF /* No virtual keycode could be deduced. */
+#define NO_VIRTUAL 0xFF /* Not generated by a key or the NSText"InputClient. */
 #define REPLACEMENT_VIRTUAL 0x80 /* A BMP char sent by the NSTextInputClient. */
 #define NON_BMP_VIRTUAL 0x81 /* A non-BMP char sent by the NSTextInputClient. */
 
 /*
- * A special character used in the keycode for modifier KeyPress or KeyRelease
- * XEvents.  It is near the end of the private-use range but different from the
- * UniChar 0xF8FF which Apple uses for their logo character.
+ * A special character is used in the keycode for simulated modifier KeyPress
+ * or KeyRelease XEvents.  It is near the end of the private-use range but
+ * different from the UniChar 0xF8FF which Apple uses for their logo character.
  */
 
 #define MOD_KEYCHAR 0xF8FE