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Asked: 2026-05-10T20:48:21+00:00

I want to display the infinity symbol using CGContextSelectFont(context, HelveticaNeue, textSize, kCGEncodingMacRoman); CGContextShowTextAtPoint(context, myCenter.x,

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I want to display the ‘infinity’ symbol using 

CGContextSelectFont(context, 'HelveticaNeue', textSize, kCGEncodingMacRoman);     CGContextShowTextAtPoint(context, myCenter.x, myCenter.y + textHeight, [sName     cStringUsingEncoding:NSMacOSRomanStringEncoding], [sName length]);

It is displayed as a square box, or a circle. I have found out this symbol is in decimal 176 and 221E in Hexadecimal format. I am using Helvetica as my font, and have tried others with no luck. Is this a problem with the encoding I am using?

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  1. It turns out that CGContextSelectFont only supports MacRoman encoding, which is basically has only a small set of characters. In order to display Unicode characters in a string, you have to use CGSetFont or the Cocoa drawing system. CGSetFont requires that you use Cocoa anyway to map characters to glyphs and then draw the glyphs using CGContextShowGlyphsAtPoint. I recommend that you look into other ways to draw these strings if you really need to display Unicode characters.

    This code basically will display the infinity symbol:

    - (void)drawRect:(CGRect)rect {     unichar inf = 0x221E; // infinity symbol     NSString* sName = [[NSString alloc] initWithCharacters:&inf length:1];     UIFont* font = [UIFont fontWithName:@'Helvetica' size:32.0];     [sName drawInRect:CGRectMake(20, 20, 40, 40)              withFont:font];     [sName release]; }

    Also note that on the iPhone (and on the Mac) Helvetica Neue actually does not exist… its name just maps back to standard Helvetica. See the table at http://daringfireball.net/misc/2007/07/iphone-osx-fonts for more information on available fonts on the iPhone.

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