Inconsistent Unicode Characters Emoji Glyphs / Symbols

Question

I am trying to use Unicode characters for astrology in products for Apple and iOS. I get inconsistent results as shown below:

Most of them come out as I like, but for some reason the Taurus symbol appears in one direction on the first line, following the Moon, and in a completely different way, with a purple button reminiscent of Emoji when it follows Mars. These results are consistent across Apple characters and hardware; here the screen shot from my phone shows the same problem with some other signs - Scorpio comes out well, but Libra and Cancer are buttons.

The strings are extremely simple; "Moon Taurus" in the first image \u263D for the Moon, \u2649 for Taurus, basically compiled as [NSString stringWithFormat:@"%@%@", @"\u263D", @"\u2649"] . The image of "Mars Taurus" is the same, only with \u2642 for Mars. Formatting strings is identical across OSX table cells and iOS AttributedString.

Any idea what makes these characters appear differently and in a different way at another time?

Answer 1

Unicode uses variational sequences to choose between different visualizations for specific code points listed in the StandardizedVariants.txt file. In your case, astrological symbols have the options "text style" and "emoji style", which are selected between U+FEOE (text style) or U+FE0F (emoji style) after the code point:

U+2650 U+FE0E : ♐︎

U+2650 U+FE0F : ♐️

Please note that the correct interpretation of the variation selector depends on the support of both the application / frame and the fonts used. In Chrome (42) there is no difference between my examples above, but in Safari (8) they are different.