Question

我是IOS的新手。所以我的问题是，我需要在两个字形之间进行字距调整。首先我尝试这样：

NSString *text = @"AB";
NSDictionary* stringAttrs = @{ NSFontAttributeName : self.level.font,         
NSKernAttributeName:@0.0f };
CGSize size = [text sizeWithAttributes:stringAttrs];

//For better understanding
NSString *textA = @"A";
NSString *textB = @"B";
CGSize sizeA = [text sizeWithAttributes:stringAttrs];
CGSize sizeB = [text sizeWithAttributes:stringAttrs];
double kerning = size.width - sizeA.width - size.widthB;

我认为，对于单个符号宽度将没有提前。但是我错了。它对我没有帮助。比我尝试过CoreText。

CFStringRef str = (__bridge CFStringRef)@"A";
CFIndex count = CFStringGetLength(str);

CTFontRef font = CTFontCreateWithName((CFStringRef)@"Lora", 100, NULL);

UniChar *characters = (UniChar *)malloc(sizeof(UniChar) * count);
CGGlyph *glyphs = (CGGlyph *)malloc(sizeof(CGGlyph) * count);

CFStringGetCharacters(str, CFRangeMake(0, count), characters);
CTFontGetGlyphsForCharacters(font, characters, glyphs, count);

CGSize *sizeCore = malloc(count * sizeof(CGSize));
CGRect *rectCore = malloc(count * sizeof(CGRect));

double adv = CTFontGetAdvancesForGlyphs (font,
                                         kCTFontHorizontalOrientation,
                                         glyphs,
                                         sizeCore,
                                         count);

CGRect rect = CTFontGetBoundingRectsForGlyphs (font,
                                               kCTFontHorizontalOrientation,
                                               glyphs,
                                               rectCore,
                                               count);

double kerning = adv - rect.size.width; (== 0)

adv给出了与rect.size.width相同的价值，即使是第一次尝试也是如此size.width

你有什么好处吗？或链接我可以找到答案。抱歉错误。

Answer 1

我发现kerning不能使用ios 7中的某些字体。请参阅我对这个问题的回答： Why Does Kerning fail for NSAttributedString in IOS7

也许它适用于不同的字体......

在IOS 7中进行字距调整

1 个答案: