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//
// GlyphDrawing.h
//
// Created by Masashi Ono on 07/07/10.
// http://akisute.com
// Original file created by Jens Egeblad on 11/16/09.
// http://mexircus.com/blog//blog4.php/2009/11/16/cgfontgetglyphsforunichars-alternatives
// http://www.mexircus.com/codes/GlyphDrawing.mm
//
//
// Purpose: Reimplement CGFontGetGlyphsForUnichars(CGFontRef, unichar[], CGGlyph[], size_t)
//
// The function that does that:
// size_t CMFontGetGlyphsForUnichars(CGFontRef cgFont, const UniChar buffer[], CGGlyph glyphs[], size_t numGlyphs)
//
// (returns number of glyps put in glyphs)
//
// Why?: We are not allowed to use it on the iPhone. Apple rejects apps with it.
//
// Why do we need it?:
// 1. UIString drawing is not thread safe
// 2. PDF drawing doesn't embeded fonts, and is therefore impossible with UIString drawing
//
// Another work-around for UIString drawing: Make sure it always occurs in main-thread with e.g. performSelector
//
// How does it work?:
// Fetch cmap (character map) table of font
// Find the right segment (We only look for platform 0 and 3 and format 4 and 12)
// Pick a platform+format for all subsequent lookups.
// Cache selection
//
// For each unichar look for character in selected cmap segment (either format 4 or 12)
//
// How well does it work?:
// This files contains testing code. All 65536 unichars are tested with our function
// and Apples. Testing generally gives perfect results for all
// current fonts except:
// + AppleGothic where there are about 300 character mismatches from char 55424 and up
// + STHeitiTC-Light and STHeitiTC-Medium which has one character mismatch
//
// Why those anomalies?: I don't know...
//
// Possible improvements:
// + cache better:
// We cache the fonttables and never release them. Consider release strateies
/// + Search faster:
// It may be possible to do binary searching in the tables if they are sorted
// which I don't know if they are
// + Add more formats: Only format 4 and 12 supported. That handles all present iPhone fonts.
// + Fix current minor issues.
//
//
// This code was mainly based on:
// http://github.com/jamesjhu/CMGlyphDrawing
//
// Other reading:
// Apple document on truetype format: http://developer.apple.com/textfonts/TTRefMan/RM06/Chap6cmap.html
// Another code: http://code.google.com/p/cocos2d-iphone/source/browse/trunk/external/FontLabel/FontLabelStringDrawing.m?spec=svn1358&r=1358
#import <Foundation/Foundation.h>
UIKIT_EXTERN size_t CMFontGetGlyphsForUnichars(CGFontRef cgFont, const UniChar buffer[], CGGlyph glyphs[], size_t numGlyphs);
// Usage: just import "GlyphDrawing.h" in GlyphDrawing.mm instead of <Foundation/Foundation.h>
@bagusflyer

Hello, can you post the GlyphDrawing.mm? because the original one from http://www.mexircus.com/codes/GlyphDrawing.mm can't be found already. Thanks

@bagusflyer

Or please email to me. My email address is bagusflyer@gmail.com. Thank you so much.

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