--- a/src/Document.h
+++ b/src/Document.h
@@ -279,6 +279,7 @@
 	int MovePositionOutsideChar(int pos, int moveDir, bool checkLineEnd=true);
 	int NextPosition(int pos, int moveDir) const;
 	bool NextCharacter(int &pos, int moveDir) const;	// Returns true if pos changed
+	int SCI_METHOD GetRelativePosition(int start, int characterOffset, int *character, int *width) const;
 	int SCI_METHOD CodePage() const;
 	bool SCI_METHOD IsDBCSLeadByte(char ch) const;
 	int SafeSegment(const char *text, int length, int lengthSegment) const;