Core Text

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Core Text is a CoreFoundation style API in Mac OS X, first introduced in Mac OS X 10.4 Tiger and made public in Mac OS X 10.5 Leopard. Written in C, it replaces the text rendering abilities of the now-deprecated QuickDraw and ATSUI frameworks in previous versions of Mac OS X. According to Apple, Core Text is "designed for high performance and ease of use" and its layout API is "simple, consistent, and tightly integrated with Core Foundation, Core Graphics, and Cocoa."^[1]

1 Features
2 Example
3 References
4 External links

[edit] Features

Core Text provides the following opaque types:

CTFramesetter - creates CTFrame objects from given attributed string object and CGPath object using CTTypesetter.
CTTypesetter - performs line layouts; e.g., line breaking
CTFrame - represents an array of lines (i.e., CTLine objects).
CTLine - represents an array of glyph runs; a glyph run is an array of glyphs sharing the same attribute.
CTFont - represents a font.

[edit] Example

The following code displays the text "Hello, World!" to the given graphics context.

// 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]), NULL, NULL);
CFAttributedStringRef attrString = CFAttributedStringCreate(NULL, CFSTR("Hello, World!"), attr);
CFRelease(attr);

// Draw the string
CTLineRef line = CTLineCreateWithAttributedString(attrString);
CGContextSetTextMatrix(context, CGAffineTransformIdentity);
CGContextSetTextPosition(context, 10, 20);
CTLineDraw(line, context);

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