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      1 /*
      2  * Copyright (C) 2006, 2007, 2008, 2009 Apple Inc. All rights reserved.
      3  * Copyright (C) 2007 Nicholas Shanks <webkit (at) nickshanks.com>
      4  *
      5  * Redistribution and use in source and binary forms, with or without
      6  * modification, are permitted provided that the following conditions
      7  * are met:
      8  *
      9  * 1.  Redistributions of source code must retain the above copyright
     10  *     notice, this list of conditions and the following disclaimer.
     11  * 2.  Redistributions in binary form must reproduce the above copyright
     12  *     notice, this list of conditions and the following disclaimer in the
     13  *     documentation and/or other materials provided with the distribution.
     14  * 3.  Neither the name of Apple Computer, Inc. ("Apple") nor the names of
     15  *     its contributors may be used to endorse or promote products derived
     16  *     from this software without specific prior written permission.
     17  *
     18  * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
     19  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
     20  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
     21  * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
     22  * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
     23  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
     24  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
     25  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
     26  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
     27  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
     28  */
     29 
     30 #import "config.h"
     31 #import "platform/fonts/FontCache.h"
     32 
     33 #import <AppKit/AppKit.h>
     34 #import "platform/LayoutTestSupport.h"
     35 #import "platform/RuntimeEnabledFeatures.h"
     36 #import "platform/fonts/FontDescription.h"
     37 #import "platform/fonts/FontFaceCreationParams.h"
     38 #import "platform/fonts/FontPlatformData.h"
     39 #import "platform/fonts/SimpleFontData.h"
     40 #import "platform/mac/WebFontCache.h"
     41 #import <wtf/MainThread.h>
     42 #import <wtf/StdLibExtras.h>
     43 
     44 // Forward declare Mac SPIs.
     45 // Request for public API: rdar://13803570
     46 @interface NSFont (WebKitSPI)
     47 + (NSFont*)findFontLike:(NSFont*)font forString:(NSString*)string withRange:(NSRange)range inLanguage:(id)useNil;
     48 + (NSFont*)findFontLike:(NSFont*)font forCharacter:(UniChar)uc inLanguage:(id)useNil;
     49 @end
     50 
     51 namespace blink {
     52 
     53 // The "void*" parameter makes the function match the prototype for callbacks from callOnMainThread.
     54 static void invalidateFontCache(void*)
     55 {
     56     if (!isMainThread()) {
     57         callOnMainThread(&invalidateFontCache, 0);
     58         return;
     59     }
     60     FontCache::fontCache()->invalidate();
     61 }
     62 
     63 static void fontCacheRegisteredFontsChangedNotificationCallback(CFNotificationCenterRef, void* observer, CFStringRef name, const void *, CFDictionaryRef)
     64 {
     65     ASSERT_UNUSED(observer, observer == FontCache::fontCache());
     66     ASSERT_UNUSED(name, CFEqual(name, kCTFontManagerRegisteredFontsChangedNotification));
     67     invalidateFontCache(0);
     68 }
     69 
     70 static bool useHinting()
     71 {
     72     // Enable hinting when subpixel font scaling is disabled or
     73     // when running the set of standard non-subpixel layout tests,
     74     // otherwise use subpixel glyph positioning.
     75     return (LayoutTestSupport::isRunningLayoutTest() && !LayoutTestSupport::isFontAntialiasingEnabledForTest()) || !RuntimeEnabledFeatures::subpixelFontScalingEnabled();
     76 }
     77 
     78 void FontCache::platformInit()
     79 {
     80     CFNotificationCenterAddObserver(CFNotificationCenterGetLocalCenter(), this, fontCacheRegisteredFontsChangedNotificationCallback, kCTFontManagerRegisteredFontsChangedNotification, 0, CFNotificationSuspensionBehaviorDeliverImmediately);
     81 }
     82 
     83 static int toAppKitFontWeight(FontWeight fontWeight)
     84 {
     85     static int appKitFontWeights[] = {
     86         2,  // FontWeight100
     87         3,  // FontWeight200
     88         4,  // FontWeight300
     89         5,  // FontWeight400
     90         6,  // FontWeight500
     91         8,  // FontWeight600
     92         9,  // FontWeight700
     93         10, // FontWeight800
     94         12, // FontWeight900
     95     };
     96     return appKitFontWeights[fontWeight];
     97 }
     98 
     99 static inline bool isAppKitFontWeightBold(NSInteger appKitFontWeight)
    100 {
    101     return appKitFontWeight >= 7;
    102 }
    103 
    104 PassRefPtr<SimpleFontData> FontCache::fallbackFontForCharacter(const FontDescription& fontDescription, UChar32 character, const SimpleFontData* fontDataToSubstitute)
    105 {
    106     // FIXME: We should fix getFallbackFamily to take a UChar32
    107     // and remove this split-to-UChar16 code.
    108     UChar codeUnits[2];
    109     int codeUnitsLength;
    110     if (character <= 0xFFFF) {
    111         codeUnits[0] = character;
    112         codeUnitsLength = 1;
    113     } else {
    114         codeUnits[0] = U16_LEAD(character);
    115         codeUnits[1] = U16_TRAIL(character);
    116         codeUnitsLength = 2;
    117     }
    118 
    119     const FontPlatformData& platformData = fontDataToSubstitute->platformData();
    120     NSFont *nsFont = platformData.font();
    121 
    122     NSString *string = [[NSString alloc] initWithCharactersNoCopy:codeUnits length:codeUnitsLength freeWhenDone:NO];
    123     NSFont *substituteFont = [NSFont findFontLike:nsFont forString:string withRange:NSMakeRange(0, codeUnitsLength) inLanguage:nil];
    124     [string release];
    125 
    126     // FIXME: Remove this SPI usage: http://crbug.com/255122
    127     if (!substituteFont && codeUnitsLength == 1)
    128         substituteFont = [NSFont findFontLike:nsFont forCharacter:codeUnits[0] inLanguage:nil];
    129     if (!substituteFont)
    130         return nullptr;
    131 
    132     // Chromium can't render AppleColorEmoji.
    133     if ([[substituteFont familyName] isEqual:@"Apple Color Emoji"])
    134         return nullptr;
    135 
    136     // Use the family name from the AppKit-supplied substitute font, requesting the
    137     // traits, weight, and size we want. One way this does better than the original
    138     // AppKit request is that it takes synthetic bold and oblique into account.
    139     // But it does create the possibility that we could end up with a font that
    140     // doesn't actually cover the characters we need.
    141 
    142     NSFontManager *fontManager = [NSFontManager sharedFontManager];
    143 
    144     NSFontTraitMask traits;
    145     NSInteger weight;
    146     CGFloat size;
    147 
    148     if (nsFont) {
    149         traits = [fontManager traitsOfFont:nsFont];
    150         if (platformData.m_syntheticBold)
    151             traits |= NSBoldFontMask;
    152         if (platformData.m_syntheticItalic)
    153             traits |= NSFontItalicTrait;
    154         weight = [fontManager weightOfFont:nsFont];
    155         size = [nsFont pointSize];
    156     } else {
    157         // For custom fonts nsFont is nil.
    158         traits = fontDescription.style() ? NSFontItalicTrait : 0;
    159         weight = toAppKitFontWeight(fontDescription.weight());
    160         size = fontDescription.computedPixelSize();
    161     }
    162 
    163     NSFontTraitMask substituteFontTraits = [fontManager traitsOfFont:substituteFont];
    164     NSInteger substituteFontWeight = [fontManager weightOfFont:substituteFont];
    165 
    166     if (traits != substituteFontTraits || weight != substituteFontWeight || !nsFont) {
    167         if (NSFont *bestVariation = [fontManager fontWithFamily:[substituteFont familyName] traits:traits weight:weight size:size]) {
    168             if ((!nsFont || [fontManager traitsOfFont:bestVariation] != substituteFontTraits || [fontManager weightOfFont:bestVariation] != substituteFontWeight)
    169                 && [[bestVariation coveredCharacterSet] longCharacterIsMember:character])
    170                 substituteFont = bestVariation;
    171         }
    172     }
    173 
    174     substituteFont = useHinting() ? [substituteFont screenFont] : [substituteFont printerFont];
    175 
    176     substituteFontTraits = [fontManager traitsOfFont:substituteFont];
    177     substituteFontWeight = [fontManager weightOfFont:substituteFont];
    178 
    179     FontPlatformData alternateFont(substituteFont, platformData.size(),
    180         isAppKitFontWeightBold(weight) && !isAppKitFontWeightBold(substituteFontWeight),
    181         (traits & NSFontItalicTrait) && !(substituteFontTraits & NSFontItalicTrait),
    182         platformData.orientation());
    183 
    184     return fontDataFromFontPlatformData(&alternateFont, DoNotRetain);
    185 }
    186 
    187 PassRefPtr<SimpleFontData> FontCache::getLastResortFallbackFont(const FontDescription& fontDescription, ShouldRetain shouldRetain)
    188 {
    189     DEFINE_STATIC_LOCAL(AtomicString, timesStr, ("Times", AtomicString::ConstructFromLiteral));
    190 
    191     // FIXME: Would be even better to somehow get the user's default font here.  For now we'll pick
    192     // the default that the user would get without changing any prefs.
    193     RefPtr<SimpleFontData> simpleFontData = getFontData(fontDescription, timesStr, false, shouldRetain);
    194     if (simpleFontData)
    195         return simpleFontData.release();
    196 
    197     // The Times fallback will almost always work, but in the highly unusual case where
    198     // the user doesn't have it, we fall back on Lucida Grande because that's
    199     // guaranteed to be there, according to Nathan Taylor. This is good enough
    200     // to avoid a crash at least.
    201     DEFINE_STATIC_LOCAL(AtomicString, lucidaGrandeStr, ("Lucida Grande", AtomicString::ConstructFromLiteral));
    202     return getFontData(fontDescription, lucidaGrandeStr, false, shouldRetain);
    203 }
    204 
    205 FontPlatformData* FontCache::createFontPlatformData(const FontDescription& fontDescription, const FontFaceCreationParams& creationParams, float fontSize)
    206 {
    207     NSFontTraitMask traits = fontDescription.style() ? NSFontItalicTrait : 0;
    208     NSInteger weight = toAppKitFontWeight(fontDescription.weight());
    209     float size = fontSize;
    210 
    211     NSFont *nsFont = [WebFontCache fontWithFamily:creationParams.family() traits:traits weight:weight size:size];
    212     if (!nsFont)
    213         return 0;
    214 
    215     NSFontManager *fontManager = [NSFontManager sharedFontManager];
    216     NSFontTraitMask actualTraits = 0;
    217     if (fontDescription.style())
    218         actualTraits = [fontManager traitsOfFont:nsFont];
    219     NSInteger actualWeight = [fontManager weightOfFont:nsFont];
    220 
    221     NSFont *platformFont = useHinting() ? [nsFont screenFont] : [nsFont printerFont];
    222     bool syntheticBold = (isAppKitFontWeightBold(weight) && !isAppKitFontWeightBold(actualWeight)) || fontDescription.isSyntheticBold();
    223     bool syntheticItalic = ((traits & NSFontItalicTrait) && !(actualTraits & NSFontItalicTrait)) || fontDescription.isSyntheticItalic();
    224 
    225     // FontPlatformData::font() can be null for the case of Chromium out-of-process font loading.
    226     // In that case, we don't want to use the platformData.
    227     OwnPtr<FontPlatformData> platformData = adoptPtr(new FontPlatformData(platformFont, size, syntheticBold, syntheticItalic, fontDescription.orientation(), fontDescription.widthVariant()));
    228     if (!platformData->font())
    229         return 0;
    230     return platformData.leakPtr();
    231 }
    232 
    233 } // namespace blink
    234