Core Text

<h2 id="features">Features</h2>
<p>Core Text provides the following opaque types:
</p>
<ul><li>CTFramesetter - creates CTFrame objects from given attributed string object and CGPath object using CTTypesetter.</li>
<li>CTTypesetter - performs line layouts; e.g., line breaking</li>
<li>CTFrame - represents an array of lines (i.e., CTLine objects).</li>
<li>CTLine - represents an array of glyph runs.</li>
<li>CTRun - an ordered collection of glyphs sharing the same attribute.</li>
<li>CTFont - represents a font.</li></ul>
<h2 id="example">Example</h2>
<p>The following code displays the text "Hello, World!" to the given graphics context in <a href="/facts/Objective-C/5mM557BW">Objective-C</a>.
</p>
// Prepare font
CTFontRef font = CTFontCreateWithName(CFSTR("Times"), 48, NULL);

// Create an attributed string
CFStringRef keys[] = { kCTFontAttributeName };
CFTypeRef values[] = { font };
CFDictionaryRef attr = CFDictionaryCreate(NULL, (const void **)&keys, (const void **)&values,
					  sizeof(keys) / sizeof(keys[0]), &kCFTypeDictionaryKeyCallBacks, &kCFTypeDictionaryValueCallBacks);
CFAttributedStringRef attrString = CFAttributedStringCreate(NULL, CFSTR("Hello, World!"), attr);
CFRelease(attr);

// Draw the string
CTLineRef line = CTLineCreateWithAttributedString(attrString);
CGContextSetTextMatrix(context, CGAffineTransformIdentity);  //Use this one when using standard view coordinates
//CGContextSetTextMatrix(context, CGAffineTransformMakeScale(1.0, -1.0)); //Use this one if the view's coordinates are flipped

CGContextSetTextPosition(context, 10, 20);
CTLineDraw(line, context);

// Clean up
CFRelease(line);
CFRelease(attrString);
CFRelease(font);

<h2 id="external-links">External links</h2>
<ul><li><a href="https://developer.apple.com/library/archive/documentation/StringsTextFonts/Conceptual/CoreText_Programming/Introduction/Introduction.html#//apple_ref/doc/uid/TP40005533">Core Text overview</a> at <a href="/facts/Apple_Developer_Connection/mHaKzeRs">Apple Developer Connection</a></li></ul>

<h2 id="references">References</h2>

<ol>
<li id="fn:1"><p>Core Text Programming Guide: Core Text Overview <a href="https://developer.apple.com/library/archive/documentation/StringsTextFonts/Conceptual/CoreText_Programming/Introduction/Introduction.html#//apple_ref/doc/uid/TP40005533" target="_blank">https://developer.apple.com/library/archive/documentation/StringsTextFonts/Conceptual/CoreText_Programming/Introduction/Introduction.html#//apple_ref/doc/uid/TP40005533</a> <a href="#fnref:1" class="footnote-back-ref">↩</a></p></li>
</ol>

Core Text open-in-new

Core Text