Returns the baseline position of a given character relative to the origin of rectangle returned by firstRectForCharacterRange:actualRange:.
Original signature is '- (CGFloat)baselineDeltaForCharacterAtIndex:(NSUInteger)anIndex'
Available in Mac OS X v10.5 and later.
- anIndex (NSUInteger)
- Index of the character whose baseline is tested.
- Available in Monobjc Bridge: 10.6 (For Mac OS X 10.6 and later), 10.5 (For Mac OS X 10.5 and later)