core-text

I have a very weird problem with core text, which sometimes randomly and sometimes reproducibly crashes my application. I use it to lay out and render a couple of pages. I do this asynchronously in the background to not block the user interface. While this works fine in general, it sometimes crashes. All these crashes happen on the very same line: framesetter = CTFramesetterCreateWithAttributedString((CFAttributedStringRef)myText); In fact, they also also seem to come from a similar point in the framework. I know you don't like it, but here's the head of a crash log: Thread 8 Crashed: 0 ???

I am using Core Text to draw some text. I would like to get the various run bounds, but when I call CTRunGetImageBounds , the rect that is returned is the correct size, but in the wrong location. Specifically, the line origin is at the end of the text as a whole. - (void)drawRect:(CGRect)rect { CGContextRef context = UIGraphicsGetCurrentContext(); self.transform = CGAffineTransformMakeScale(1.0, -1.0); CGContextSetTextMatrix(context, CGAffineTransformIdentity); [[UIColor whiteColor] set]; CGContextFillRect(context, self.bounds); NSMutableAttributedString* attrString = [

I have 2 attributed strings say 'A' and '.' I need to calculate the height of each of these strings. Currently the height returned is the same for both, it seems to return the maximum possible height for the tallest character in a given font (even if that character isn't present in the string). I would like to get the exact pixel height for each of these characters, so that I can resize a view around them that fits the character (glyph) snugly. I've tried using CTFramesetterSuggestFrameSizeWithConstraints() and CTLineGetTypographicBounds() but it returns a number similar to the attributed

I am a developing an iPad application in which i have to use CTRunDelegate . I have defined all the the callbacks that are required viz CTRunDelegateGetAscentCallback , CTRunDelegateGetDescentCallback , CTRunDelegateGetWidthCallback . I dont know how to use CTRunDelegateRef object that I am creating. Right now what is happening is that my callbacks are not getting called. Any pointers in this regard will be highly appreciated. Thanx in advance. You should add your run delegate as an attribute for a range of characters in your attributed string. See Core Text String Attributes . When drawing,

How would I get a CGRect from an NSRange for text rendered with Core Text? I am using Core Text with an NSAttributedString . It is an absolute pain but can be done. You need to get all of the lines in the frame using CTFrameGetLines() , check if their character range is in the range you're looking for using CTLineGetStringRange() , use CTLineGetTypographicBounds() to find how big the line itself would render as, and use CTLineGetOffsetForStringIndex() to determine the actual position of the start/end character of the range (if the line is just a subrange of the desired range). Combining all of

I need to draw centered text to a CGContext. I started with a Cocoa approach. I created a NSCell with the text and tried to draw it thus: NSGraphicsContext* newCtx = [NSGraphicsContext graphicsContextWithGraphicsPort:bitmapContext flipped:true]; [NSGraphicsContext saveGraphicsState]; [NSGraphicsContext setCurrentContext:newCtx]; [pCell setFont:font]; [pCell drawWithFrame:rect inView:nil]; [NSGraphicsContext restoreGraphicsState]; But the CGBitmapContext doesn't seem to have the text rendered on it. Possibly because I have to pass nil for the inView: parameter. So I tried switching text

Does CoreText have any facility for selecting a SmallCaps variant of a font, or for synthesizing small caps if the font doesn't have that feature? I can't find anything in the CoreText documentation that talks about small caps, though there are facilities for dealing with font variations/features. Has anyone done anything similar to this? It's generally easiest to use CTFontDescriptorCreateCopyWithFeature . As you mentioned in your own answer, this will only work for fonts that actually implement the feature you are requesting. The answer appears to be a qualified Yes. It supports fonts that