Shape text with system font.

systemfont.m

// systemfont.m

#import <Cocoa/Cocoa.h>

int main(int argc, char const *argv[]) {
    NSFont* font = [NSFont menuFontOfSize:18.0];

    CTFontRef ctFont = (CTFontRef)font;
    CFStringRef str = CFSTR("Opera");

    UniChar characters[5];
    CFStringGetCharacters(str, CFRangeMake(0, 5), characters);

    CGGlyph glyphs[5];
    CTFontGetGlyphsForCharacters(ctFont, characters, glyphs, 5);

    CGSize advances[5];
    CTFontGetAdvancesForGlyphs(ctFont, kCTFontHorizontalOrientation, glyphs, advances, 5);

    for (int i = 0; i < 5; i++)
        printf("%d [%g] ", glyphs[i], advances[i].width);

    printf("\n");

    CFAttributedStringRef attrStr =
        CFAttributedStringCreate(NULL, str,
            (CFDictionaryRef)@{(NSString*)kCTFontAttributeName: font});

    CTLineRef line = CTLineCreateWithAttributedString(attrStr);
    CFArrayRef runs = CTLineGetGlyphRuns(line);

    for (int i = 0; i < CFArrayGetCount(runs); i++) {
        CTRunRef run = CFArrayGetValueAtIndex(runs, i);
        CFIndex count = CTRunGetGlyphCount(run);
        CGGlyph glyphs[100];
        CTRunGetGlyphs(run, CFRangeMake(0, count), glyphs);

        CGSize advances[100];
        CTRunGetAdvances(run, CFRangeMake(0, count), advances);

        for (int j = 0; j < count; j++)
            printf("%d [%g] ", glyphs[j], advances[j].width);

        printf("\n");
    }

    return 0;
}