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gerrit-public.fairphone.software / platform / external / skia / 9a9eae21ed5235869702a66d6decddd6643792c3 / . / src / ports / SkFontHost_mac.cpp
blob: 21a2b956148b8ac53a17d2a3b94498ffdbf51e18 [file] [log] [blame]
/*
* Copyright 2006 The Android Open Source Project
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#include <vector>
#ifdef SK_BUILD_FOR_MAC
#import <ApplicationServices/ApplicationServices.h>
#endif
#ifdef SK_BUILD_FOR_IOS
#include <CoreText/CoreText.h>
#include <CoreText/CTFontManager.h>
#include <CoreGraphics/CoreGraphics.h>
#include <CoreFoundation/CoreFoundation.h>
#endif
#include "SkFontHost.h"
#include "SkCGUtils.h"
#include "SkColorPriv.h"
#include "SkDescriptor.h"
#include "SkEndian.h"
#include "SkFontDescriptor.h"
#include "SkFloatingPoint.h"
#include "SkGlyph.h"
#include "SkMaskGamma.h"
#include "SkSFNTHeader.h"
#include "SkOTTable_glyf.h"
#include "SkOTTable_head.h"
#include "SkOTTable_hhea.h"
#include "SkOTTable_loca.h"
#include "SkOTUtils.h"
#include "SkPaint.h"
#include "SkPath.h"
#include "SkString.h"
#include "SkStream.h"
#include "SkThread.h"
#include "SkTypeface_mac.h"
#include "SkUtils.h"
#include "SkTypefaceCache.h"
#include "SkFontMgr.h"
#include "SkUtils.h"
//#define HACK_COLORGLYPHS
class SkScalerContext_Mac;
// CTFontManagerCopyAvailableFontFamilyNames() is not always available, so we
// provide a wrapper here that will return an empty array if need be.
static CFArrayRef SkCTFontManagerCopyAvailableFontFamilyNames() {
#ifdef SK_BUILD_FOR_IOS
return CFArrayCreate(NULL, NULL, 0, NULL);
#else
return CTFontManagerCopyAvailableFontFamilyNames();
#endif
}
// Being templated and taking const T* prevents calling
// CFSafeRelease(autoCFRelease) through implicit conversion.
template <typename T> static void CFSafeRelease(/*CFTypeRef*/const T* cfTypeRef) {
if (cfTypeRef) {
CFRelease(cfTypeRef);
}
}
// Being templated and taking const T* prevents calling
// CFSafeRetain(autoCFRelease) through implicit conversion.
template <typename T> static void CFSafeRetain(/*CFTypeRef*/const T* cfTypeRef) {
if (cfTypeRef) {
CFRetain(cfTypeRef);
}
}
/** Acts like a CFRef, but calls CFSafeRelease when it goes out of scope. */
template<typename CFRef> class AutoCFRelease : private SkNoncopyable {
public:
explicit AutoCFRelease(CFRef cfRef = NULL) : fCFRef(cfRef) { }
~AutoCFRelease() { CFSafeRelease(fCFRef); }
void reset(CFRef that = NULL) {
CFSafeRetain(that);
CFSafeRelease(fCFRef);
fCFRef = that;
}
AutoCFRelease& operator =(CFRef that) {
reset(that);
return *this;
}
operator CFRef() const { return fCFRef; }
CFRef get() const { return fCFRef; }
CFRef* operator&() { SkASSERT(fCFRef == NULL); return &fCFRef; }
private:
CFRef fCFRef;
};
static CFStringRef make_CFString(const char str[]) {
return CFStringCreateWithCString(NULL, str, kCFStringEncodingUTF8);
}
template<typename T> class AutoCGTable : SkNoncopyable {
public:
AutoCGTable(CGFontRef font)
//Undocumented: the tag parameter in this call is expected in machine order and not BE order.
: fCFData(CGFontCopyTableForTag(font, SkSetFourByteTag(T::TAG0, T::TAG1, T::TAG2, T::TAG3)))
, fData(fCFData ? reinterpret_cast<const T*>(CFDataGetBytePtr(fCFData)) : NULL)
{ }
const T* operator->() const { return fData; }
private:
AutoCFRelease<CFDataRef> fCFData;
public:
const T* fData;
};
// inline versions of these rect helpers
static bool CGRectIsEmpty_inline(const CGRect& rect) {
return rect.size.width <= 0 || rect.size.height <= 0;
}
static CGFloat CGRectGetMinX_inline(const CGRect& rect) {
return rect.origin.x;
}
static CGFloat CGRectGetMaxX_inline(const CGRect& rect) {
return rect.origin.x + rect.size.width;
}
static CGFloat CGRectGetMinY_inline(const CGRect& rect) {
return rect.origin.y;
}
static CGFloat CGRectGetMaxY_inline(const CGRect& rect) {
return rect.origin.y + rect.size.height;
}
static CGFloat CGRectGetWidth_inline(const CGRect& rect) {
return rect.size.width;
}
///////////////////////////////////////////////////////////////////////////////
static void sk_memset_rect32(uint32_t* ptr, uint32_t value,
int width, int height, size_t rowBytes) {
SkASSERT(width);
SkASSERT(width * sizeof(uint32_t) <= rowBytes);
if (width >= 32) {
while (height) {
sk_memset32(ptr, value, width);
ptr = (uint32_t*)((char*)ptr + rowBytes);
height -= 1;
}
return;
}
rowBytes -= width * sizeof(uint32_t);
if (width >= 8) {
while (height) {
int w = width;
do {
*ptr++ = value; *ptr++ = value;
*ptr++ = value; *ptr++ = value;
*ptr++ = value; *ptr++ = value;
*ptr++ = value; *ptr++ = value;
w -= 8;
} while (w >= 8);
while (--w >= 0) {
*ptr++ = value;
}
ptr = (uint32_t*)((char*)ptr + rowBytes);
height -= 1;
}
} else {
while (height) {
int w = width;
do {
*ptr++ = value;
} while (--w > 0);
ptr = (uint32_t*)((char*)ptr + rowBytes);
height -= 1;
}
}
}
#include <sys/utsname.h>
typedef uint32_t CGRGBPixel;
static unsigned CGRGBPixel_getAlpha(CGRGBPixel pixel) {
return pixel & 0xFF;
}
// The calls to support subpixel are present in 10.5, but are not included in
// the 10.5 SDK. The needed calls have been extracted from the 10.6 SDK and are
// included below. To verify that CGContextSetShouldSubpixelQuantizeFonts, for
// instance, is present in the 10.5 CoreGraphics libary, use:
// cd /Developer/SDKs/MacOSX10.5.sdk/System/Library/Frameworks/
// cd ApplicationServices.framework/Frameworks/CoreGraphics.framework/
// nm CoreGraphics | grep CGContextSetShouldSubpixelQuantizeFonts
#if !defined(MAC_OS_X_VERSION_10_6) || (MAC_OS_X_VERSION_MAX_ALLOWED < MAC_OS_X_VERSION_10_6)
CG_EXTERN void CGContextSetAllowsFontSmoothing(CGContextRef context, bool value);
CG_EXTERN void CGContextSetAllowsFontSubpixelPositioning(CGContextRef context, bool value);
CG_EXTERN void CGContextSetShouldSubpixelPositionFonts(CGContextRef context, bool value);
CG_EXTERN void CGContextSetAllowsFontSubpixelQuantization(CGContextRef context, bool value);
CG_EXTERN void CGContextSetShouldSubpixelQuantizeFonts(CGContextRef context, bool value);
#endif
static const char FONT_DEFAULT_NAME[] = "Lucida Sans";
// See Source/WebKit/chromium/base/mac/mac_util.mm DarwinMajorVersionInternal for original source.
static int readVersion() {
struct utsname info;
if (uname(&info) != 0) {
SkDebugf("uname failed\n");
return 0;
}
if (strcmp(info.sysname, "Darwin") != 0) {
SkDebugf("unexpected uname sysname %s\n", info.sysname);
return 0;
}
char* dot = strchr(info.release, '.');
if (!dot) {
SkDebugf("expected dot in uname release %s\n", info.release);
return 0;
}
int version = atoi(info.release);
if (version == 0) {
SkDebugf("could not parse uname release %s\n", info.release);
}
return version;
}
static int darwinVersion() {
static int darwin_version = readVersion();
return darwin_version;
}
static bool isSnowLeopard() {
return darwinVersion() == 10;
}
static bool isLion() {
return darwinVersion() == 11;
}
static bool isMountainLion() {
return darwinVersion() == 12;
}
static bool isLCDFormat(unsigned format) {
return SkMask::kLCD16_Format == format || SkMask::kLCD32_Format == format;
}
static CGFloat ScalarToCG(SkScalar scalar) {
if (sizeof(CGFloat) == sizeof(float)) {
return SkScalarToFloat(scalar);
} else {
SkASSERT(sizeof(CGFloat) == sizeof(double));
return (CGFloat) SkScalarToDouble(scalar);
}
}
static SkScalar CGToScalar(CGFloat cgFloat) {
if (sizeof(CGFloat) == sizeof(float)) {
return cgFloat;
} else {
SkASSERT(sizeof(CGFloat) == sizeof(double));
return SkDoubleToScalar(cgFloat);
}
}
static CGAffineTransform MatrixToCGAffineTransform(const SkMatrix& matrix,
SkScalar sx = SK_Scalar1,
SkScalar sy = SK_Scalar1) {
return CGAffineTransformMake( ScalarToCG(matrix[SkMatrix::kMScaleX] * sx),
-ScalarToCG(matrix[SkMatrix::kMSkewY] * sy),
-ScalarToCG(matrix[SkMatrix::kMSkewX] * sx),
ScalarToCG(matrix[SkMatrix::kMScaleY] * sy),
ScalarToCG(matrix[SkMatrix::kMTransX] * sx),
ScalarToCG(matrix[SkMatrix::kMTransY] * sy));
}
///////////////////////////////////////////////////////////////////////////////
#define BITMAP_INFO_RGB (kCGImageAlphaNoneSkipFirst | kCGBitmapByteOrder32Host)
#define BITMAP_INFO_GRAY (kCGImageAlphaNone)
/**
* There does not appear to be a publicly accessable API for determining if lcd
* font smoothing will be applied if we request it. The main issue is that if
* smoothing is applied a gamma of 2.0 will be used, if not a gamma of 1.0.
*/
static bool supports_LCD() {
static int gSupportsLCD = -1;
if (gSupportsLCD >= 0) {
return (bool) gSupportsLCD;
}
uint32_t rgb = 0;
AutoCFRelease<CGColorSpaceRef> colorspace(CGColorSpaceCreateDeviceRGB());
AutoCFRelease<CGContextRef> cgContext(CGBitmapContextCreate(&rgb, 1, 1, 8, 4,
colorspace, BITMAP_INFO_RGB));
CGContextSelectFont(cgContext, "Helvetica", 16, kCGEncodingMacRoman);
CGContextSetShouldSmoothFonts(cgContext, true);
CGContextSetShouldAntialias(cgContext, true);
CGContextSetTextDrawingMode(cgContext, kCGTextFill);
CGContextSetGrayFillColor(cgContext, 1, 1);
CGContextShowTextAtPoint(cgContext, -1, 0, "|", 1);
uint32_t r = (rgb >> 16) & 0xFF;
uint32_t g = (rgb >> 8) & 0xFF;
uint32_t b = (rgb >> 0) & 0xFF;
gSupportsLCD = (r != g || r != b);
return (bool) gSupportsLCD;
}
class Offscreen {
public:
Offscreen();
CGRGBPixel* getCG(const SkScalerContext_Mac& context, const SkGlyph& glyph,
CGGlyph glyphID, size_t* rowBytesPtr,
bool generateA8FromLCD);
private:
enum {
kSize = 32 * 32 * sizeof(CGRGBPixel)
};
SkAutoSMalloc<kSize> fImageStorage;
AutoCFRelease<CGColorSpaceRef> fRGBSpace;
// cached state
AutoCFRelease<CGContextRef> fCG;
SkISize fSize;
bool fDoAA;
bool fDoLCD;
static int RoundSize(int dimension) {
return SkNextPow2(dimension);
}
};
Offscreen::Offscreen() : fRGBSpace(NULL), fCG(NULL),
fDoAA(false), fDoLCD(false) {
fSize.set(0, 0);
}
///////////////////////////////////////////////////////////////////////////////
static SkTypeface::Style computeStyleBits(CTFontRef font, bool* isFixedPitch) {
unsigned style = SkTypeface::kNormal;
CTFontSymbolicTraits traits = CTFontGetSymbolicTraits(font);
if (traits & kCTFontBoldTrait) {
style |= SkTypeface::kBold;
}
if (traits & kCTFontItalicTrait) {
style |= SkTypeface::kItalic;
}
if (isFixedPitch) {
*isFixedPitch = (traits & kCTFontMonoSpaceTrait) != 0;
}
return (SkTypeface::Style)style;
}
static SkFontID CTFontRef_to_SkFontID(CTFontRef fontRef) {
SkFontID id = 0;
// CTFontGetPlatformFont and ATSFontRef are not supported on iOS, so we have to
// bracket this to be Mac only.
#ifdef SK_BUILD_FOR_MAC
ATSFontRef ats = CTFontGetPlatformFont(fontRef, NULL);
id = (SkFontID)ats;
if (id != 0) {
id &= 0x3FFFFFFF; // make top two bits 00
return id;
}
#endif
// CTFontGetPlatformFont returns NULL if the font is local
// (e.g., was created by a CSS3 @font-face rule).
AutoCFRelease<CGFontRef> cgFont(CTFontCopyGraphicsFont(fontRef, NULL));
AutoCGTable<SkOTTableHead> headTable(cgFont);
if (headTable.fData) {
id = (SkFontID) headTable->checksumAdjustment;
id = (id & 0x3FFFFFFF) | 0x40000000; // make top two bits 01
}
// well-formed fonts have checksums, but as a last resort, use the pointer.
if (id == 0) {
id = (SkFontID) (uintptr_t) fontRef;
id = (id & 0x3FFFFFFF) | 0x80000000; // make top two bits 10
}
return id;
}
static SkFontStyle stylebits2fontstyle(SkTypeface::Style styleBits) {
return SkFontStyle((styleBits & SkTypeface::kBold)
? SkFontStyle::kBold_Weight
: SkFontStyle::kNormal_Weight,
SkFontStyle::kNormal_Width,
(styleBits & SkTypeface::kItalic)
? SkFontStyle::kItalic_Slant
: SkFontStyle::kUpright_Slant);
}
#define WEIGHT_THRESHOLD ((SkFontStyle::kNormal_Weight + SkFontStyle::kBold_Weight)/2)
static SkTypeface::Style fontstyle2stylebits(const SkFontStyle& fs) {
unsigned style = 0;
if (fs.width() >= WEIGHT_THRESHOLD) {
style |= SkTypeface::kBold;
}
if (fs.isItalic()) {
style |= SkTypeface::kItalic;
}
return (SkTypeface::Style)style;
}
class SkTypeface_Mac : public SkTypeface {
public:
SkTypeface_Mac(SkTypeface::Style style, SkFontID fontID, bool isFixedPitch,
CTFontRef fontRef, const char name[], bool isLocalStream)
: SkTypeface(style, fontID, isFixedPitch)
, fName(name)
, fFontRef(fontRef) // caller has already called CFRetain for us
, fFontStyle(stylebits2fontstyle(style))
, fIsLocalStream(isLocalStream)
{
SkASSERT(fontRef);
}
SkTypeface_Mac(const SkFontStyle& fs, SkFontID fontID, bool isFixedPitch,
CTFontRef fontRef, const char name[], bool isLocalStream)
: SkTypeface(fontstyle2stylebits(fs), fontID, isFixedPitch)
, fName(name)
, fFontRef(fontRef) // caller has already called CFRetain for us
, fFontStyle(fs)
, fIsLocalStream(isLocalStream)
{
SkASSERT(fontRef);
}
SkString fName;
AutoCFRelease<CTFontRef> fFontRef;
SkFontStyle fFontStyle;
protected:
friend class SkFontHost; // to access our protected members for deprecated methods
virtual int onGetUPEM() const SK_OVERRIDE;
virtual SkStream* onOpenStream(int* ttcIndex) const SK_OVERRIDE;
virtual SkTypeface::LocalizedStrings* onCreateFamilyNameIterator() const SK_OVERRIDE;
virtual int onGetTableTags(SkFontTableTag tags[]) const SK_OVERRIDE;
virtual size_t onGetTableData(SkFontTableTag, size_t offset,
size_t length, void* data) const SK_OVERRIDE;
virtual SkScalerContext* onCreateScalerContext(const SkDescriptor*) const SK_OVERRIDE;
virtual void onFilterRec(SkScalerContextRec*) const SK_OVERRIDE;
virtual void onGetFontDescriptor(SkFontDescriptor*, bool*) const SK_OVERRIDE;
virtual SkAdvancedTypefaceMetrics* onGetAdvancedTypefaceMetrics(
SkAdvancedTypefaceMetrics::PerGlyphInfo,
const uint32_t*, uint32_t) const SK_OVERRIDE;
virtual int onCharsToGlyphs(const void* chars, Encoding, uint16_t glyphs[],
int glyphCount) const SK_OVERRIDE;
virtual int onCountGlyphs() const SK_OVERRIDE;
private:
bool fIsLocalStream;
typedef SkTypeface INHERITED;
};
static SkTypeface* NewFromFontRef(CTFontRef fontRef, const char name[], bool isLocalStream) {
SkASSERT(fontRef);
bool isFixedPitch;
SkTypeface::Style style = computeStyleBits(fontRef, &isFixedPitch);
SkFontID fontID = CTFontRef_to_SkFontID(fontRef);
return new SkTypeface_Mac(style, fontID, isFixedPitch, fontRef, name, isLocalStream);
}
static SkTypeface* NewFromName(const char familyName[], SkTypeface::Style theStyle) {
CTFontRef ctFont = NULL;
CTFontSymbolicTraits ctFontTraits = 0;
if (theStyle & SkTypeface::kBold) {
ctFontTraits |= kCTFontBoldTrait;
}
if (theStyle & SkTypeface::kItalic) {
ctFontTraits |= kCTFontItalicTrait;
}
// Create the font info
AutoCFRelease<CFStringRef> cfFontName(make_CFString(familyName));
AutoCFRelease<CFNumberRef> cfFontTraits(
CFNumberCreate(kCFAllocatorDefault, kCFNumberSInt32Type, &ctFontTraits));
AutoCFRelease<CFMutableDictionaryRef> cfAttributes(
CFDictionaryCreateMutable(kCFAllocatorDefault, 0,
&kCFTypeDictionaryKeyCallBacks,
&kCFTypeDictionaryValueCallBacks));
AutoCFRelease<CFMutableDictionaryRef> cfTraits(
CFDictionaryCreateMutable(kCFAllocatorDefault, 0,
&kCFTypeDictionaryKeyCallBacks,
&kCFTypeDictionaryValueCallBacks));
// Create the font
if (cfFontName != NULL && cfFontTraits != NULL && cfAttributes != NULL && cfTraits != NULL) {
CFDictionaryAddValue(cfTraits, kCTFontSymbolicTrait, cfFontTraits);
CFDictionaryAddValue(cfAttributes, kCTFontFamilyNameAttribute, cfFontName);
CFDictionaryAddValue(cfAttributes, kCTFontTraitsAttribute, cfTraits);
AutoCFRelease<CTFontDescriptorRef> ctFontDesc(
CTFontDescriptorCreateWithAttributes(cfAttributes));
if (ctFontDesc != NULL) {
ctFont = CTFontCreateWithFontDescriptor(ctFontDesc, 0, NULL);
}
}
return ctFont ? NewFromFontRef(ctFont, familyName, false) : NULL;
}
static SkTypeface* GetDefaultFace() {
SK_DECLARE_STATIC_MUTEX(gMutex);
SkAutoMutexAcquire ma(gMutex);
static SkTypeface* gDefaultFace;
if (NULL == gDefaultFace) {
gDefaultFace = NewFromName(FONT_DEFAULT_NAME, SkTypeface::kNormal);
SkTypefaceCache::Add(gDefaultFace, SkTypeface::kNormal);
}
return gDefaultFace;
}
///////////////////////////////////////////////////////////////////////////////
extern CTFontRef SkTypeface_GetCTFontRef(const SkTypeface* face);
CTFontRef SkTypeface_GetCTFontRef(const SkTypeface* face) {
const SkTypeface_Mac* macface = (const SkTypeface_Mac*)face;
return macface ? macface->fFontRef.get() : NULL;
}
/* This function is visible on the outside. It first searches the cache, and if
* not found, returns a new entry (after adding it to the cache).
*/
SkTypeface* SkCreateTypefaceFromCTFont(CTFontRef fontRef) {
SkFontID fontID = CTFontRef_to_SkFontID(fontRef);
SkTypeface* face = SkTypefaceCache::FindByID(fontID);
if (face) {
face->ref();
} else {
face = NewFromFontRef(fontRef, NULL, false);
SkTypefaceCache::Add(face, face->style());
// NewFromFontRef doesn't retain the parameter, but the typeface it
// creates does release it in its destructor, so we balance that with
// a retain call here.
CFRetain(fontRef);
}
SkASSERT(face->getRefCnt() > 1);
return face;
}
struct NameStyleRec {
const char* fName;
SkTypeface::Style fStyle;
};
static bool FindByNameStyle(SkTypeface* face, SkTypeface::Style style,
void* ctx) {
const SkTypeface_Mac* mface = reinterpret_cast<SkTypeface_Mac*>(face);
const NameStyleRec* rec = reinterpret_cast<const NameStyleRec*>(ctx);
return rec->fStyle == style && mface->fName.equals(rec->fName);
}
static const char* map_css_names(const char* name) {
static const struct {
const char* fFrom; // name the caller specified
const char* fTo; // "canonical" name we map to
} gPairs[] = {
{ "sans-serif", "Helvetica" },
{ "serif", "Times" },
{ "monospace", "Courier" }
};
for (size_t i = 0; i < SK_ARRAY_COUNT(gPairs); i++) {
if (strcmp(name, gPairs[i].fFrom) == 0) {
return gPairs[i].fTo;
}
}
return name; // no change
}
static SkTypeface* create_typeface(const SkTypeface* familyFace,
const char familyName[],
SkTypeface::Style style) {
if (familyName) {
familyName = map_css_names(familyName);
}
// Clone an existing typeface
// TODO: only clone if style matches the familyFace's style...
if (familyName == NULL && familyFace != NULL) {
familyFace->ref();
return const_cast<SkTypeface*>(familyFace);
}
if (!familyName || !*familyName) {
familyName = FONT_DEFAULT_NAME;
}
NameStyleRec rec = { familyName, style };
SkTypeface* face = SkTypefaceCache::FindByProcAndRef(FindByNameStyle, &rec);
if (NULL == face) {
face = NewFromName(familyName, style);
if (face) {
SkTypefaceCache::Add(face, style);
} else {
face = GetDefaultFace();
face->ref();
}
}
return face;
}
///////////////////////////////////////////////////////////////////////////////
/** GlyphRect is in FUnits (em space, y up). */
struct GlyphRect {
int16_t fMinX;
int16_t fMinY;
int16_t fMaxX;
int16_t fMaxY;
};
class SkScalerContext_Mac : public SkScalerContext {
public:
SkScalerContext_Mac(SkTypeface_Mac*, const SkDescriptor*);
protected:
unsigned generateGlyphCount(void) SK_OVERRIDE;
uint16_t generateCharToGlyph(SkUnichar uni) SK_OVERRIDE;
void generateAdvance(SkGlyph* glyph) SK_OVERRIDE;
void generateMetrics(SkGlyph* glyph) SK_OVERRIDE;
void generateImage(const SkGlyph& glyph) SK_OVERRIDE;
void generatePath(const SkGlyph& glyph, SkPath* path) SK_OVERRIDE;
void generateFontMetrics(SkPaint::FontMetrics*) SK_OVERRIDE;
private:
static void CTPathElement(void *info, const CGPathElement *element);
/** Returns the offset from the horizontal origin to the vertical origin in SkGlyph units. */
void getVerticalOffset(CGGlyph glyphID, SkPoint* offset) const;
/** Initializes and returns the value of fFBoundingBoxesGlyphOffset.
*
* For use with (and must be called before) generateBBoxes.
*/
uint16_t getFBoundingBoxesGlyphOffset();
/** Initializes fFBoundingBoxes and returns true on success.
*
* On Lion and Mountain Lion, CTFontGetBoundingRectsForGlyphs has a bug which causes it to
* return a bad value in bounds.origin.x for SFNT fonts whose hhea::numberOfHMetrics is
* less than its maxp::numGlyphs. When this is the case we try to read the bounds from the
* font directly.
*
* This routine initializes fFBoundingBoxes to an array of
* fGlyphCount - fFBoundingBoxesGlyphOffset GlyphRects which contain the bounds in FUnits
* (em space, y up) of glyphs with ids in the range [fFBoundingBoxesGlyphOffset, fGlyphCount).
*
* Returns true if fFBoundingBoxes is properly initialized. The table can only be properly
* initialized for a TrueType font with 'head', 'loca', and 'glyf' tables.
*
* TODO: A future optimization will compute fFBoundingBoxes once per fCTFont.
*/
bool generateBBoxes();
/** Converts from FUnits (em space, y up) to SkGlyph units (pixels, y down).
*
* Used on Snow Leopard to correct CTFontGetVerticalTranslationsForGlyphs.
* Used on Lion to correct CTFontGetBoundingRectsForGlyphs.
*/
SkMatrix fFUnitMatrix;
Offscreen fOffscreen;
AutoCFRelease<CTFontRef> fCTFont;
/** Vertical variant of fCTFont.
*
* CT vertical metrics are pre-rotated (in em space, before transform) 90deg clock-wise.
* This makes kCTFontDefaultOrientation dangerous, because the metrics from
* kCTFontHorizontalOrientation are in a different space from kCTFontVerticalOrientation.
* Use fCTVerticalFont with kCTFontVerticalOrientation to get metrics in the same space.
*/
AutoCFRelease<CTFontRef> fCTVerticalFont;
AutoCFRelease<CGFontRef> fCGFont;
SkAutoTMalloc<GlyphRect> fFBoundingBoxes;
uint16_t fFBoundingBoxesGlyphOffset;
uint16_t fGlyphCount;
bool fGeneratedFBoundingBoxes;
const bool fDoSubPosition;
const bool fVertical;
friend class Offscreen;
typedef SkScalerContext INHERITED;
};
SkScalerContext_Mac::SkScalerContext_Mac(SkTypeface_Mac* typeface,
const SkDescriptor* desc)
: INHERITED(typeface, desc)
, fFBoundingBoxes()
, fFBoundingBoxesGlyphOffset(0)
, fGeneratedFBoundingBoxes(false)
, fDoSubPosition(SkToBool(fRec.fFlags & kSubpixelPositioning_Flag))
, fVertical(SkToBool(fRec.fFlags & kVertical_Flag))
{
CTFontRef ctFont = typeface->fFontRef.get();
CFIndex numGlyphs = CTFontGetGlyphCount(ctFont);
SkASSERT(numGlyphs >= 1 && numGlyphs <= 0xFFFF);
fGlyphCount = SkToU16(numGlyphs);
fRec.getSingleMatrix(&fFUnitMatrix);
CGAffineTransform transform = MatrixToCGAffineTransform(fFUnitMatrix);
AutoCFRelease<CTFontDescriptorRef> ctFontDesc;
if (fVertical) {
AutoCFRelease<CFMutableDictionaryRef> cfAttributes(CFDictionaryCreateMutable(
kCFAllocatorDefault, 0,
&kCFTypeDictionaryKeyCallBacks,
&kCFTypeDictionaryValueCallBacks));
if (cfAttributes) {
CTFontOrientation ctOrientation = kCTFontVerticalOrientation;
AutoCFRelease<CFNumberRef> cfVertical(CFNumberCreate(
kCFAllocatorDefault, kCFNumberSInt32Type, &ctOrientation));
CFDictionaryAddValue(cfAttributes, kCTFontOrientationAttribute, cfVertical);
ctFontDesc = CTFontDescriptorCreateWithAttributes(cfAttributes);
}
}
// Since our matrix includes everything, we pass 1 for size.
fCTFont = CTFontCreateCopyWithAttributes(ctFont, 1, &transform, ctFontDesc);
fCGFont = CTFontCopyGraphicsFont(fCTFont, NULL);
if (fVertical) {
CGAffineTransform rotateLeft = CGAffineTransformMake(0, -1, 1, 0, 0, 0);
transform = CGAffineTransformConcat(rotateLeft, transform);
fCTVerticalFont = CTFontCreateCopyWithAttributes(ctFont, 1, &transform, NULL);
}
SkScalar emPerFUnit = SkScalarInvert(SkIntToScalar(CGFontGetUnitsPerEm(fCGFont)));
fFUnitMatrix.preScale(emPerFUnit, -emPerFUnit);
}
CGRGBPixel* Offscreen::getCG(const SkScalerContext_Mac& context, const SkGlyph& glyph,
CGGlyph glyphID, size_t* rowBytesPtr,
bool generateA8FromLCD) {
if (!fRGBSpace) {
//It doesn't appear to matter what color space is specified.
//Regular blends and antialiased text are always (s*a + d*(1-a))
//and smoothed text is always g=2.0.
fRGBSpace = CGColorSpaceCreateDeviceRGB();
}
// default to kBW_Format
bool doAA = false;
bool doLCD = false;
if (SkMask::kBW_Format != glyph.fMaskFormat) {
doLCD = true;
doAA = true;
}
// FIXME: lcd smoothed un-hinted rasterization unsupported.
if (!generateA8FromLCD && SkMask::kA8_Format == glyph.fMaskFormat) {
doLCD = false;
doAA = true;
}
size_t rowBytes = fSize.fWidth * sizeof(CGRGBPixel);
if (!fCG || fSize.fWidth < glyph.fWidth || fSize.fHeight < glyph.fHeight) {
if (fSize.fWidth < glyph.fWidth) {
fSize.fWidth = RoundSize(glyph.fWidth);
}
if (fSize.fHeight < glyph.fHeight) {
fSize.fHeight = RoundSize(glyph.fHeight);
}
rowBytes = fSize.fWidth * sizeof(CGRGBPixel);
void* image = fImageStorage.reset(rowBytes * fSize.fHeight);
fCG = CGBitmapContextCreate(image, fSize.fWidth, fSize.fHeight, 8,
rowBytes, fRGBSpace, BITMAP_INFO_RGB);
// skia handles quantization itself, so we disable this for cg to get
// full fractional data from them.
CGContextSetAllowsFontSubpixelQuantization(fCG, false);
CGContextSetShouldSubpixelQuantizeFonts(fCG, false);
CGContextSetTextDrawingMode(fCG, kCGTextFill);
CGContextSetFont(fCG, context.fCGFont);
CGContextSetFontSize(fCG, 1 /*CTFontGetSize(context.fCTFont)*/);
CGContextSetTextMatrix(fCG, CTFontGetMatrix(context.fCTFont));
// Because CG always draws from the horizontal baseline,
// if there is a non-integral translation from the horizontal origin to the vertical origin,
// then CG cannot draw the glyph in the correct location without subpixel positioning.
CGContextSetAllowsFontSubpixelPositioning(fCG, context.fDoSubPosition || context.fVertical);
CGContextSetShouldSubpixelPositionFonts(fCG, context.fDoSubPosition || context.fVertical);
// Draw white on black to create mask.
// TODO: Draw black on white and invert, CG has a special case codepath.
CGContextSetGrayFillColor(fCG, 1.0f, 1.0f);
// force our checks below to happen
fDoAA = !doAA;
fDoLCD = !doLCD;
}
if (fDoAA != doAA) {
CGContextSetShouldAntialias(fCG, doAA);
fDoAA = doAA;
}
if (fDoLCD != doLCD) {
CGContextSetShouldSmoothFonts(fCG, doLCD);
fDoLCD = doLCD;
}
CGRGBPixel* image = (CGRGBPixel*)fImageStorage.get();
// skip rows based on the glyph's height
image += (fSize.fHeight - glyph.fHeight) * fSize.fWidth;
// erase to black
sk_memset_rect32(image, 0, glyph.fWidth, glyph.fHeight, rowBytes);
float subX = 0;
float subY = 0;
if (context.fDoSubPosition) {
subX = SkFixedToFloat(glyph.getSubXFixed());
subY = SkFixedToFloat(glyph.getSubYFixed());
}
// CGContextShowGlyphsAtPoint always draws using the horizontal baseline origin.
if (context.fVertical) {
SkPoint offset;
context.getVerticalOffset(glyphID, &offset);
subX += offset.fX;
subY += offset.fY;
}
CGContextShowGlyphsAtPoint(fCG, -glyph.fLeft + subX,
glyph.fTop + glyph.fHeight - subY,
&glyphID, 1);
SkASSERT(rowBytesPtr);
*rowBytesPtr = rowBytes;
return image;
}
void SkScalerContext_Mac::getVerticalOffset(CGGlyph glyphID, SkPoint* offset) const {
// Snow Leopard returns cgVertOffset in completely un-transformed FUnits (em space, y up).
// Lion and Leopard return cgVertOffset in CG units (pixels, y up).
CGSize cgVertOffset;
CTFontGetVerticalTranslationsForGlyphs(fCTFont, &glyphID, &cgVertOffset, 1);
SkPoint skVertOffset = { CGToScalar(cgVertOffset.width), CGToScalar(cgVertOffset.height) };
if (isSnowLeopard()) {
// From FUnits (em space, y up) to SkGlyph units (pixels, y down).
fFUnitMatrix.mapPoints(&skVertOffset, 1);
} else {
// From CG units (pixels, y up) to SkGlyph units (pixels, y down).
skVertOffset.fY = -skVertOffset.fY;
}
*offset = skVertOffset;
}
uint16_t SkScalerContext_Mac::getFBoundingBoxesGlyphOffset() {
if (fFBoundingBoxesGlyphOffset) {
return fFBoundingBoxesGlyphOffset;
}
fFBoundingBoxesGlyphOffset = fGlyphCount; // fallback for all fonts
AutoCGTable<SkOTTableHorizontalHeader> hheaTable(fCGFont);
if (hheaTable.fData) {
fFBoundingBoxesGlyphOffset = SkEndian_SwapBE16(hheaTable->numberOfHMetrics);
}
return fFBoundingBoxesGlyphOffset;
}
bool SkScalerContext_Mac::generateBBoxes() {
if (fGeneratedFBoundingBoxes) {
return NULL != fFBoundingBoxes.get();
}
fGeneratedFBoundingBoxes = true;
AutoCGTable<SkOTTableHead> headTable(fCGFont);
if (!headTable.fData) {
return false;
}
AutoCGTable<SkOTTableIndexToLocation> locaTable(fCGFont);
if (!locaTable.fData) {
return false;
}
AutoCGTable<SkOTTableGlyph> glyfTable(fCGFont);
if (!glyfTable.fData) {
return false;
}
uint16_t entries = fGlyphCount - fFBoundingBoxesGlyphOffset;
fFBoundingBoxes.reset(entries);
SkOTTableHead::IndexToLocFormat locaFormat = headTable->indexToLocFormat;
SkOTTableGlyph::Iterator glyphDataIter(*glyfTable.fData, *locaTable.fData, locaFormat);
glyphDataIter.advance(fFBoundingBoxesGlyphOffset);
for (uint16_t boundingBoxesIndex = 0; boundingBoxesIndex < entries; ++boundingBoxesIndex) {
const SkOTTableGlyphData* glyphData = glyphDataIter.next();
GlyphRect& rect = fFBoundingBoxes[boundingBoxesIndex];
rect.fMinX = SkEndian_SwapBE16(glyphData->xMin);
rect.fMinY = SkEndian_SwapBE16(glyphData->yMin);
rect.fMaxX = SkEndian_SwapBE16(glyphData->xMax);
rect.fMaxY = SkEndian_SwapBE16(glyphData->yMax);
}
return true;
}
unsigned SkScalerContext_Mac::generateGlyphCount(void) {
return fGlyphCount;
}
uint16_t SkScalerContext_Mac::generateCharToGlyph(SkUnichar uni) {
CGGlyph cgGlyph[2];
UniChar theChar[2]; // UniChar is a UTF-16 16-bit code unit.
// Get the glyph
size_t numUniChar = SkUTF16_FromUnichar(uni, theChar);
SkASSERT(sizeof(CGGlyph) <= sizeof(uint16_t));
// Undocumented behavior of CTFontGetGlyphsForCharacters with non-bmp code points:
// When a surrogate pair is detected, the glyph index used is the index of the high surrogate.
// It is documented that if a mapping is unavailable, the glyph will be set to 0.
CTFontGetGlyphsForCharacters(fCTFont, theChar, cgGlyph, numUniChar);
return cgGlyph[0];
}
void SkScalerContext_Mac::generateAdvance(SkGlyph* glyph) {
this->generateMetrics(glyph);
}
void SkScalerContext_Mac::generateMetrics(SkGlyph* glyph) {
const CGGlyph cgGlyph = (CGGlyph) glyph->getGlyphID(fBaseGlyphCount);
glyph->zeroMetrics();
// The following block produces cgAdvance in CG units (pixels, y up).
CGSize cgAdvance;
if (fVertical) {
CTFontGetAdvancesForGlyphs(fCTVerticalFont, kCTFontVerticalOrientation,
&cgGlyph, &cgAdvance, 1);
} else {
CTFontGetAdvancesForGlyphs(fCTFont, kCTFontHorizontalOrientation,
&cgGlyph, &cgAdvance, 1);
}
glyph->fAdvanceX = SkFloatToFixed_Check(cgAdvance.width);
glyph->fAdvanceY = -SkFloatToFixed_Check(cgAdvance.height);
// The following produces skBounds in SkGlyph units (pixels, y down),
// or returns early if skBounds would be empty.
SkRect skBounds;
// On Mountain Lion, CTFontGetBoundingRectsForGlyphs with kCTFontVerticalOrientation and
// CTFontGetVerticalTranslationsForGlyphs do not agree when using OTF CFF fonts.
// For TTF fonts these two do agree and we can use CTFontGetBoundingRectsForGlyphs to get
// the bounding box and CTFontGetVerticalTranslationsForGlyphs to then draw the glyph
// inside that bounding box. However, with OTF CFF fonts this does not work. It appears that
// CTFontGetBoundingRectsForGlyphs with kCTFontVerticalOrientation on OTF CFF fonts tries
// to center the glyph along the vertical baseline and also perform some mysterious shift
// along the baseline. CTFontGetVerticalTranslationsForGlyphs does not appear to perform
// these steps.
//
// It is not known which is correct (or if either is correct). However, we must always draw
// from the horizontal origin and must use CTFontGetVerticalTranslationsForGlyphs to draw.
// As a result, we do not call CTFontGetBoundingRectsForGlyphs for vertical glyphs.
// On Snow Leopard, CTFontGetBoundingRectsForGlyphs ignores kCTFontVerticalOrientation and
// returns horizontal bounds.
// On Lion and Mountain Lion, CTFontGetBoundingRectsForGlyphs has a bug which causes it to
// return a bad value in cgBounds.origin.x for SFNT fonts whose hhea::numberOfHMetrics is
// less than its maxp::numGlyphs. When this is the case we try to read the bounds from the
// font directly.
if ((isLion() || isMountainLion()) &&
(cgGlyph < fGlyphCount && cgGlyph >= getFBoundingBoxesGlyphOffset() && generateBBoxes()))
{
const GlyphRect& gRect = fFBoundingBoxes[cgGlyph - fFBoundingBoxesGlyphOffset];
if (gRect.fMinX >= gRect.fMaxX || gRect.fMinY >= gRect.fMaxY) {
return;
}
skBounds = SkRect::MakeLTRB(gRect.fMinX, gRect.fMinY, gRect.fMaxX, gRect.fMaxY);
// From FUnits (em space, y up) to SkGlyph units (pixels, y down).
fFUnitMatrix.mapRect(&skBounds);
} else {
// CTFontGetBoundingRectsForGlyphs produces cgBounds in CG units (pixels, y up).
CGRect cgBounds;
CTFontGetBoundingRectsForGlyphs(fCTFont, kCTFontHorizontalOrientation,
&cgGlyph, &cgBounds, 1);
// BUG?
// 0x200B (zero-advance space) seems to return a huge (garbage) bounds, when
// it should be empty. So, if we see a zero-advance, we check if it has an
// empty path or not, and if so, we jam the bounds to 0. Hopefully a zero-advance
// is rare, so we won't incur a big performance cost for this extra check.
if (0 == cgAdvance.width && 0 == cgAdvance.height) {
AutoCFRelease<CGPathRef> path(CTFontCreatePathForGlyph(fCTFont, cgGlyph, NULL));
if (NULL == path || CGPathIsEmpty(path)) {
return;
}
}
if (CGRectIsEmpty_inline(cgBounds)) {
return;
}
// Convert cgBounds to SkGlyph units (pixels, y down).
skBounds = SkRect::MakeXYWH(cgBounds.origin.x, -cgBounds.origin.y - cgBounds.size.height,
cgBounds.size.width, cgBounds.size.height);
}
if (fVertical) {
// Due to all of the vertical bounds bugs, skBounds is always the horizontal bounds.
// Convert these horizontal bounds into vertical bounds.
SkPoint offset;
getVerticalOffset(cgGlyph, &offset);
skBounds.offset(offset);
}
// Currently the bounds are based on being rendered at (0,0).
// The top left must not move, since that is the base from which subpixel positioning is offset.
if (fDoSubPosition) {
skBounds.fRight += SkFixedToFloat(glyph->getSubXFixed());
skBounds.fBottom += SkFixedToFloat(glyph->getSubYFixed());
}
SkIRect skIBounds;
skBounds.roundOut(&skIBounds);
// Expand the bounds by 1 pixel, to give CG room for anti-aliasing.
// Note that this outset is to allow room for LCD smoothed glyphs. However, the correct outset
// is not currently known, as CG dilates the outlines by some percentage.
// Note that if this context is A8 and not back-forming from LCD, there is no need to outset.
skIBounds.outset(1, 1);
glyph->fLeft = SkToS16(skIBounds.fLeft);
glyph->fTop = SkToS16(skIBounds.fTop);
glyph->fWidth = SkToU16(skIBounds.width());
glyph->fHeight = SkToU16(skIBounds.height());
#ifdef HACK_COLORGLYPHS
glyph->fMaskFormat = SkMask::kARGB32_Format;
#endif
}
#include "SkColorPriv.h"
static void build_power_table(uint8_t table[], float ee) {
for (int i = 0; i < 256; i++) {
float x = i / 255.f;
x = sk_float_pow(x, ee);
int xx = SkScalarRoundToInt(x * 255);
table[i] = SkToU8(xx);
}
}
/**
* This will invert the gamma applied by CoreGraphics, so we can get linear
* values.
*
* CoreGraphics obscurely defaults to 2.0 as the smoothing gamma value.
* The color space used does not appear to affect this choice.
*/
static const uint8_t* getInverseGammaTableCoreGraphicSmoothing() {
static bool gInited;
static uint8_t gTableCoreGraphicsSmoothing[256];
if (!gInited) {
build_power_table(gTableCoreGraphicsSmoothing, 2.0f);
gInited = true;
}
return gTableCoreGraphicsSmoothing;
}
static void cgpixels_to_bits(uint8_t dst[], const CGRGBPixel src[], int count) {
while (count > 0) {
uint8_t mask = 0;
for (int i = 7; i >= 0; --i) {
mask |= (CGRGBPixel_getAlpha(*src++) >> 7) << i;
if (0 == --count) {
break;
}
}
*dst++ = mask;
}
}
template<bool APPLY_PREBLEND>
static inline uint8_t rgb_to_a8(CGRGBPixel rgb, const uint8_t* table8) {
U8CPU r = (rgb >> 16) & 0xFF;
U8CPU g = (rgb >> 8) & 0xFF;
U8CPU b = (rgb >> 0) & 0xFF;
return sk_apply_lut_if<APPLY_PREBLEND>(SkComputeLuminance(r, g, b), table8);
}
template<bool APPLY_PREBLEND>
static void rgb_to_a8(const CGRGBPixel* SK_RESTRICT cgPixels, size_t cgRowBytes,
const SkGlyph& glyph, const uint8_t* table8) {
const int width = glyph.fWidth;
size_t dstRB = glyph.rowBytes();
uint8_t* SK_RESTRICT dst = (uint8_t*)glyph.fImage;
for (int y = 0; y < glyph.fHeight; y++) {
for (int i = 0; i < width; ++i) {
dst[i] = rgb_to_a8<APPLY_PREBLEND>(cgPixels[i], table8);
}
cgPixels = (CGRGBPixel*)((char*)cgPixels + cgRowBytes);
dst += dstRB;
}
}
template<bool APPLY_PREBLEND>
static inline uint16_t rgb_to_lcd16(CGRGBPixel rgb, const uint8_t* tableR,
const uint8_t* tableG,
const uint8_t* tableB) {
U8CPU r = sk_apply_lut_if<APPLY_PREBLEND>((rgb >> 16) & 0xFF, tableR);
U8CPU g = sk_apply_lut_if<APPLY_PREBLEND>((rgb >> 8) & 0xFF, tableG);
U8CPU b = sk_apply_lut_if<APPLY_PREBLEND>((rgb >> 0) & 0xFF, tableB);
return SkPack888ToRGB16(r, g, b);
}
template<bool APPLY_PREBLEND>
static void rgb_to_lcd16(const CGRGBPixel* SK_RESTRICT cgPixels, size_t cgRowBytes, const SkGlyph& glyph,
const uint8_t* tableR, const uint8_t* tableG, const uint8_t* tableB) {
const int width = glyph.fWidth;
size_t dstRB = glyph.rowBytes();
uint16_t* SK_RESTRICT dst = (uint16_t*)glyph.fImage;
for (int y = 0; y < glyph.fHeight; y++) {
for (int i = 0; i < width; i++) {
dst[i] = rgb_to_lcd16<APPLY_PREBLEND>(cgPixels[i], tableR, tableG, tableB);
}
cgPixels = (CGRGBPixel*)((char*)cgPixels + cgRowBytes);
dst = (uint16_t*)((char*)dst + dstRB);
}
}
template<bool APPLY_PREBLEND>
static inline uint32_t rgb_to_lcd32(CGRGBPixel rgb, const uint8_t* tableR,
const uint8_t* tableG,
const uint8_t* tableB) {
U8CPU r = sk_apply_lut_if<APPLY_PREBLEND>((rgb >> 16) & 0xFF, tableR);
U8CPU g = sk_apply_lut_if<APPLY_PREBLEND>((rgb >> 8) & 0xFF, tableG);
U8CPU b = sk_apply_lut_if<APPLY_PREBLEND>((rgb >> 0) & 0xFF, tableB);
return SkPackARGB32(0xFF, r, g, b);
}
template<bool APPLY_PREBLEND>
static void rgb_to_lcd32(const CGRGBPixel* SK_RESTRICT cgPixels, size_t cgRowBytes, const SkGlyph& glyph,
const uint8_t* tableR, const uint8_t* tableG, const uint8_t* tableB) {
const int width = glyph.fWidth;
size_t dstRB = glyph.rowBytes();
uint32_t* SK_RESTRICT dst = (uint32_t*)glyph.fImage;
for (int y = 0; y < glyph.fHeight; y++) {
for (int i = 0; i < width; i++) {
dst[i] = rgb_to_lcd32<APPLY_PREBLEND>(cgPixels[i], tableR, tableG, tableB);
}
cgPixels = (CGRGBPixel*)((char*)cgPixels + cgRowBytes);
dst = (uint32_t*)((char*)dst + dstRB);
}
}
#ifdef HACK_COLORGLYPHS
// hack to colorize the output for testing kARGB32_Format
static SkPMColor cgpixels_to_pmcolor(CGRGBPixel rgb, const SkGlyph& glyph,
int x, int y) {
U8CPU r = (rgb >> 16) & 0xFF;
U8CPU g = (rgb >> 8) & 0xFF;
U8CPU b = (rgb >> 0) & 0xFF;
unsigned a = SkComputeLuminance(r, g, b);
// compute gradient from x,y
r = x * 255 / glyph.fWidth;
g = 0;
b = (glyph.fHeight - y) * 255 / glyph.fHeight;
return SkPreMultiplyARGB(a, r, g, b); // red
}
#endif
template <typename T> T* SkTAddByteOffset(T* ptr, size_t byteOffset) {
return (T*)((char*)ptr + byteOffset);
}
void SkScalerContext_Mac::generateImage(const SkGlyph& glyph) {
CGGlyph cgGlyph = (CGGlyph) glyph.getGlyphID(fBaseGlyphCount);
// FIXME: lcd smoothed un-hinted rasterization unsupported.
bool generateA8FromLCD = fRec.getHinting() != SkPaint::kNo_Hinting;
// Draw the glyph
size_t cgRowBytes;
CGRGBPixel* cgPixels = fOffscreen.getCG(*this, glyph, cgGlyph, &cgRowBytes, generateA8FromLCD);
if (cgPixels == NULL) {
return;
}
//TODO: see if drawing black on white and inverting is faster (at least in
//lcd case) as core graphics appears to have special case code for drawing
//black text.
// Fix the glyph
const bool isLCD = isLCDFormat(glyph.fMaskFormat);
if (isLCD || (glyph.fMaskFormat == SkMask::kA8_Format && supports_LCD() && generateA8FromLCD)) {
const uint8_t* table = getInverseGammaTableCoreGraphicSmoothing();
//Note that the following cannot really be integrated into the
//pre-blend, since we may not be applying the pre-blend; when we aren't
//applying the pre-blend it means that a filter wants linear anyway.
//Other code may also be applying the pre-blend, so we'd need another
//one with this and one without.
CGRGBPixel* addr = cgPixels;
for (int y = 0; y < glyph.fHeight; ++y) {
for (int x = 0; x < glyph.fWidth; ++x) {
int r = (addr[x] >> 16) & 0xFF;
int g = (addr[x] >> 8) & 0xFF;
int b = (addr[x] >> 0) & 0xFF;
addr[x] = (table[r] << 16) | (table[g] << 8) | table[b];
}
addr = SkTAddByteOffset(addr, cgRowBytes);
}
}
// Convert glyph to mask
switch (glyph.fMaskFormat) {
case SkMask::kLCD32_Format: {
if (fPreBlend.isApplicable()) {
rgb_to_lcd32<true>(cgPixels, cgRowBytes, glyph,
fPreBlend.fR, fPreBlend.fG, fPreBlend.fB);
} else {
rgb_to_lcd32<false>(cgPixels, cgRowBytes, glyph,
fPreBlend.fR, fPreBlend.fG, fPreBlend.fB);
}
} break;
case SkMask::kLCD16_Format: {
if (fPreBlend.isApplicable()) {
rgb_to_lcd16<true>(cgPixels, cgRowBytes, glyph,
fPreBlend.fR, fPreBlend.fG, fPreBlend.fB);
} else {
rgb_to_lcd16<false>(cgPixels, cgRowBytes, glyph,
fPreBlend.fR, fPreBlend.fG, fPreBlend.fB);
}
} break;
case SkMask::kA8_Format: {
if (fPreBlend.isApplicable()) {
rgb_to_a8<true>(cgPixels, cgRowBytes, glyph, fPreBlend.fG);
} else {
rgb_to_a8<false>(cgPixels, cgRowBytes, glyph, fPreBlend.fG);
}
} break;
case SkMask::kBW_Format: {
const int width = glyph.fWidth;
size_t dstRB = glyph.rowBytes();
uint8_t* dst = (uint8_t*)glyph.fImage;
for (int y = 0; y < glyph.fHeight; y++) {
cgpixels_to_bits(dst, cgPixels, width);
cgPixels = (CGRGBPixel*)((char*)cgPixels + cgRowBytes);
dst += dstRB;
}
} break;
#ifdef HACK_COLORGLYPHS
case SkMask::kARGB32_Format: {
const int width = glyph.fWidth;
size_t dstRB = glyph.rowBytes();
SkPMColor* dst = (SkPMColor*)glyph.fImage;
for (int y = 0; y < glyph.fHeight; y++) {
for (int x = 0; x < width; ++x) {
dst[x] = cgpixels_to_pmcolor(cgPixels[x], glyph, x, y);
}
cgPixels = (CGRGBPixel*)((char*)cgPixels + cgRowBytes);
dst = (SkPMColor*)((char*)dst + dstRB);
}
} break;
#endif
default:
SkDEBUGFAIL("unexpected mask format");
break;
}
}
/*
* Our subpixel resolution is only 2 bits in each direction, so a scale of 4
* seems sufficient, and possibly even correct, to allow the hinted outline
* to be subpixel positioned.
*/
#define kScaleForSubPixelPositionHinting (4.0f)
void SkScalerContext_Mac::generatePath(const SkGlyph& glyph, SkPath* path) {
CTFontRef font = fCTFont;
SkScalar scaleX = SK_Scalar1;
SkScalar scaleY = SK_Scalar1;
/*
* For subpixel positioning, we want to return an unhinted outline, so it
* can be positioned nicely at fractional offsets. However, we special-case
* if the baseline of the (horizontal) text is axis-aligned. In those cases
* we want to retain hinting in the direction orthogonal to the baseline.
* e.g. for horizontal baseline, we want to retain hinting in Y.
* The way we remove hinting is to scale the font by some value (4) in that
* direction, ask for the path, and then scale the path back down.
*/
if (fRec.fFlags & SkScalerContext::kSubpixelPositioning_Flag) {
SkMatrix m;
fRec.getSingleMatrix(&m);
// start out by assuming that we want no hining in X and Y
scaleX = scaleY = kScaleForSubPixelPositionHinting;
// now see if we need to restore hinting for axis-aligned baselines
switch (SkComputeAxisAlignmentForHText(m)) {
case kX_SkAxisAlignment:
scaleY = SK_Scalar1; // want hinting in the Y direction
break;
case kY_SkAxisAlignment:
scaleX = SK_Scalar1; // want hinting in the X direction
break;
default:
break;
}
CGAffineTransform xform = MatrixToCGAffineTransform(m, scaleX, scaleY);
// need to release font when we're done
font = CTFontCreateCopyWithAttributes(fCTFont, 1, &xform, NULL);
}
CGGlyph cgGlyph = (CGGlyph)glyph.getGlyphID(fBaseGlyphCount);
AutoCFRelease<CGPathRef> cgPath(CTFontCreatePathForGlyph(font, cgGlyph, NULL));
path->reset();
if (cgPath != NULL) {
CGPathApply(cgPath, path, SkScalerContext_Mac::CTPathElement);
}
if (fDoSubPosition) {
SkMatrix m;
m.setScale(SkScalarInvert(scaleX), SkScalarInvert(scaleY));
path->transform(m);
// balance the call to CTFontCreateCopyWithAttributes
CFSafeRelease(font);
}
if (fVertical) {
SkPoint offset;
getVerticalOffset(cgGlyph, &offset);
path->offset(offset.fX, offset.fY);
}
}
void SkScalerContext_Mac::generateFontMetrics(SkPaint::FontMetrics* metrics) {
if (NULL == metrics) {
return;
}
CGRect theBounds = CTFontGetBoundingBox(fCTFont);
metrics->fTop = CGToScalar(-CGRectGetMaxY_inline(theBounds));
metrics->fAscent = CGToScalar(-CTFontGetAscent(fCTFont));
metrics->fDescent = CGToScalar( CTFontGetDescent(fCTFont));
metrics->fBottom = CGToScalar(-CGRectGetMinY_inline(theBounds));
metrics->fLeading = CGToScalar( CTFontGetLeading(fCTFont));
metrics->fAvgCharWidth = CGToScalar( CGRectGetWidth_inline(theBounds));
metrics->fXMin = CGToScalar( CGRectGetMinX_inline(theBounds));
metrics->fXMax = CGToScalar( CGRectGetMaxX_inline(theBounds));
metrics->fXHeight = CGToScalar( CTFontGetXHeight(fCTFont));
metrics->fUnderlineThickness = CGToScalar( CTFontGetUnderlineThickness(fCTFont));
metrics->fUnderlinePosition = -CGToScalar( CTFontGetUnderlinePosition(fCTFont));
metrics->fFlags |= SkPaint::FontMetrics::kUnderlineThinknessIsValid_Flag;
metrics->fFlags |= SkPaint::FontMetrics::kUnderlinePositionIsValid_Flag;
}
void SkScalerContext_Mac::CTPathElement(void *info, const CGPathElement *element) {
SkPath* skPath = (SkPath*)info;
// Process the path element
switch (element->type) {
case kCGPathElementMoveToPoint:
skPath->moveTo(element->points[0].x, -element->points[0].y);
break;
case kCGPathElementAddLineToPoint:
skPath->lineTo(element->points[0].x, -element->points[0].y);
break;
case kCGPathElementAddQuadCurveToPoint:
skPath->quadTo(element->points[0].x, -element->points[0].y,
element->points[1].x, -element->points[1].y);
break;
case kCGPathElementAddCurveToPoint:
skPath->cubicTo(element->points[0].x, -element->points[0].y,
element->points[1].x, -element->points[1].y,
element->points[2].x, -element->points[2].y);
break;
case kCGPathElementCloseSubpath:
skPath->close();
break;
default:
SkDEBUGFAIL("Unknown path element!");
break;
}
}
///////////////////////////////////////////////////////////////////////////////
// Returns NULL on failure
// Call must still manage its ownership of provider
static SkTypeface* create_from_dataProvider(CGDataProviderRef provider) {
AutoCFRelease<CGFontRef> cg(CGFontCreateWithDataProvider(provider));
if (NULL == cg) {
return NULL;
}
CTFontRef ct = CTFontCreateWithGraphicsFont(cg, 0, NULL, NULL);
return ct ? NewFromFontRef(ct, NULL, true) : NULL;
}
// Web fonts added to the the CTFont registry do not return their character set.
// Iterate through the font in this case. The existing caller caches the result,
// so the performance impact isn't too bad.
static void populate_glyph_to_unicode_slow(CTFontRef ctFont, CFIndex glyphCount,
SkTDArray<SkUnichar>* glyphToUnicode) {
glyphToUnicode->setCount(SkToInt(glyphCount));
SkUnichar* out = glyphToUnicode->begin();
sk_bzero(out, glyphCount * sizeof(SkUnichar));
UniChar unichar = 0;
while (glyphCount > 0) {
CGGlyph glyph;
if (CTFontGetGlyphsForCharacters(ctFont, &unichar, &glyph, 1)) {
out[glyph] = unichar;
--glyphCount;
}
if (++unichar == 0) {
break;
}
}
}
// Construct Glyph to Unicode table.
// Unicode code points that require conjugate pairs in utf16 are not
// supported.
static void populate_glyph_to_unicode(CTFontRef ctFont, CFIndex glyphCount,
SkTDArray<SkUnichar>* glyphToUnicode) {
AutoCFRelease<CFCharacterSetRef> charSet(CTFontCopyCharacterSet(ctFont));
if (!charSet) {
populate_glyph_to_unicode_slow(ctFont, glyphCount, glyphToUnicode);
return;
}
AutoCFRelease<CFDataRef> bitmap(CFCharacterSetCreateBitmapRepresentation(kCFAllocatorDefault,
charSet));
if (!bitmap) {
return;
}
CFIndex length = CFDataGetLength(bitmap);
if (!length) {
return;
}
if (length > 8192) {
// TODO: Add support for Unicode above 0xFFFF
// Consider only the BMP portion of the Unicode character points.
// The bitmap may contain other planes, up to plane 16.
// See http://developer.apple.com/library/ios/#documentation/CoreFoundation/Reference/CFCharacterSetRef/Reference/reference.html
length = 8192;
}
const UInt8* bits = CFDataGetBytePtr(bitmap);
glyphToUnicode->setCount(SkToInt(glyphCount));
SkUnichar* out = glyphToUnicode->begin();
sk_bzero(out, glyphCount * sizeof(SkUnichar));
for (int i = 0; i < length; i++) {
int mask = bits[i];
if (!mask) {
continue;
}
for (int j = 0; j < 8; j++) {
CGGlyph glyph;
UniChar unichar = static_cast<UniChar>((i << 3) + j);
if (mask & (1 << j) && CTFontGetGlyphsForCharacters(ctFont, &unichar, &glyph, 1)) {
out[glyph] = unichar;
}
}
}
}
static bool getWidthAdvance(CTFontRef ctFont, int gId, int16_t* data) {
CGSize advance;
advance.width = 0;
CGGlyph glyph = gId;
CTFontGetAdvancesForGlyphs(ctFont, kCTFontHorizontalOrientation, &glyph, &advance, 1);
*data = sk_float_round2int(advance.width);
return true;
}
/** Assumes src and dst are not NULL. */
static void CFStringToSkString(CFStringRef src, SkString* dst) {
// Reserve enough room for the worst-case string,
// plus 1 byte for the trailing null.
CFIndex length = CFStringGetMaximumSizeForEncoding(CFStringGetLength(src),
kCFStringEncodingUTF8) + 1;
dst->resize(length);
CFStringGetCString(src, dst->writable_str(), length, kCFStringEncodingUTF8);
// Resize to the actual UTF-8 length used, stripping the null character.
dst->resize(strlen(dst->c_str()));
}
SkAdvancedTypefaceMetrics* SkTypeface_Mac::onGetAdvancedTypefaceMetrics(
SkAdvancedTypefaceMetrics::PerGlyphInfo perGlyphInfo,
const uint32_t* glyphIDs,
uint32_t glyphIDsCount) const {
CTFontRef originalCTFont = fFontRef.get();
AutoCFRelease<CTFontRef> ctFont(CTFontCreateCopyWithAttributes(
originalCTFont, CTFontGetUnitsPerEm(originalCTFont), NULL, NULL));
SkAdvancedTypefaceMetrics* info = new SkAdvancedTypefaceMetrics;
{
AutoCFRelease<CFStringRef> fontName(CTFontCopyPostScriptName(ctFont));
if (fontName.get()) {
CFStringToSkString(fontName, &info->fFontName);
}
}
CFIndex glyphCount = CTFontGetGlyphCount(ctFont);
info->fLastGlyphID = SkToU16(glyphCount - 1);
info->fEmSize = CTFontGetUnitsPerEm(ctFont);
info->fFlags = SkAdvancedTypefaceMetrics::kEmpty_FontFlag;
info->fStyle = 0;
if (perGlyphInfo & SkAdvancedTypefaceMetrics::kToUnicode_PerGlyphInfo) {
populate_glyph_to_unicode(ctFont, glyphCount, &info->fGlyphToUnicode);
}
// If it's not a truetype font, mark it as 'other'. Assume that TrueType
// fonts always have both glyf and loca tables. At the least, this is what
// sfntly needs to subset the font. CTFontCopyAttribute() does not always
// succeed in determining this directly.
if (!this->getTableSize('glyf') || !this->getTableSize('loca')) {
info->fType = SkAdvancedTypefaceMetrics::kOther_Font;
info->fItalicAngle = 0;
info->fAscent = 0;
info->fDescent = 0;
info->fStemV = 0;
info->fCapHeight = 0;
info->fBBox = SkIRect::MakeEmpty();
return info;
}
info->fType = SkAdvancedTypefaceMetrics::kTrueType_Font;
CTFontSymbolicTraits symbolicTraits = CTFontGetSymbolicTraits(ctFont);
if (symbolicTraits & kCTFontMonoSpaceTrait) {
info->fStyle |= SkAdvancedTypefaceMetrics::kFixedPitch_Style;
}
if (symbolicTraits & kCTFontItalicTrait) {
info->fStyle |= SkAdvancedTypefaceMetrics::kItalic_Style;
}
CTFontStylisticClass stylisticClass = symbolicTraits & kCTFontClassMaskTrait;
if (stylisticClass >= kCTFontOldStyleSerifsClass && stylisticClass <= kCTFontSlabSerifsClass) {
info->fStyle |= SkAdvancedTypefaceMetrics::kSerif_Style;
} else if (stylisticClass & kCTFontScriptsClass) {
info->fStyle |= SkAdvancedTypefaceMetrics::kScript_Style;
}
info->fItalicAngle = (int16_t) CTFontGetSlantAngle(ctFont);
info->fAscent = (int16_t) CTFontGetAscent(ctFont);
info->fDescent = (int16_t) CTFontGetDescent(ctFont);
info->fCapHeight = (int16_t) CTFontGetCapHeight(ctFont);
CGRect bbox = CTFontGetBoundingBox(ctFont);
SkRect r;
r.set( CGToScalar(CGRectGetMinX_inline(bbox)), // Left
CGToScalar(CGRectGetMaxY_inline(bbox)), // Top
CGToScalar(CGRectGetMaxX_inline(bbox)), // Right
CGToScalar(CGRectGetMinY_inline(bbox))); // Bottom
r.roundOut(&(info->fBBox));
// Figure out a good guess for StemV - Min width of i, I, !, 1.
// This probably isn't very good with an italic font.
int16_t min_width = SHRT_MAX;
info->fStemV = 0;
static const UniChar stem_chars[] = {'i', 'I', '!', '1'};
const size_t count = sizeof(stem_chars) / sizeof(stem_chars[0]);
CGGlyph glyphs[count];
CGRect boundingRects[count];
if (CTFontGetGlyphsForCharacters(ctFont, stem_chars, glyphs, count)) {
CTFontGetBoundingRectsForGlyphs(ctFont, kCTFontHorizontalOrientation,
glyphs, boundingRects, count);
for (size_t i = 0; i < count; i++) {
int16_t width = (int16_t) boundingRects[i].size.width;
if (width > 0 && width < min_width) {
min_width = width;
info->fStemV = min_width;
}
}
}
if (perGlyphInfo & SkAdvancedTypefaceMetrics::kHAdvance_PerGlyphInfo) {
if (info->fStyle & SkAdvancedTypefaceMetrics::kFixedPitch_Style) {
skia_advanced_typeface_metrics_utils::appendRange(&info->fGlyphWidths, 0);
info->fGlyphWidths->fAdvance.append(1, &min_width);
skia_advanced_typeface_metrics_utils::finishRange(info->fGlyphWidths.get(), 0,
SkAdvancedTypefaceMetrics::WidthRange::kDefault);
} else {
info->fGlyphWidths.reset(
skia_advanced_typeface_metrics_utils::getAdvanceData(ctFont.get(),
SkToInt(glyphCount),
glyphIDs,
glyphIDsCount,
&getWidthAdvance));
}
}
return info;
}
///////////////////////////////////////////////////////////////////////////////
static SK_SFNT_ULONG get_font_type_tag(const SkTypeface_Mac* typeface) {
CTFontRef ctFont = typeface->fFontRef.get();
AutoCFRelease<CFNumberRef> fontFormatRef(
static_cast<CFNumberRef>(CTFontCopyAttribute(ctFont, kCTFontFormatAttribute)));
if (!fontFormatRef) {
return 0;
}
SInt32 fontFormatValue;
if (!CFNumberGetValue(fontFormatRef, kCFNumberSInt32Type, &fontFormatValue)) {
return 0;
}
switch (fontFormatValue) {
case kCTFontFormatOpenTypePostScript:
return SkSFNTHeader::fontType_OpenTypeCFF::TAG;
case kCTFontFormatOpenTypeTrueType:
return SkSFNTHeader::fontType_WindowsTrueType::TAG;
case kCTFontFormatTrueType:
return SkSFNTHeader::fontType_MacTrueType::TAG;
case kCTFontFormatPostScript:
return SkSFNTHeader::fontType_PostScript::TAG;
case kCTFontFormatBitmap:
return SkSFNTHeader::fontType_MacTrueType::TAG;
case kCTFontFormatUnrecognized:
default:
//CT seems to be unreliable in being able to obtain the type,
//even if all we want is the first four bytes of the font resource.
//Just the presence of the FontForge 'FFTM' table seems to throw it off.
return SkSFNTHeader::fontType_WindowsTrueType::TAG;
}
}
SkStream* SkTypeface_Mac::onOpenStream(int* ttcIndex) const {
SK_SFNT_ULONG fontType = get_font_type_tag(this);
if (0 == fontType) {
return NULL;
}
// get table tags
int numTables = this->countTables();
SkTDArray<SkFontTableTag> tableTags;
tableTags.setCount(numTables);
this->getTableTags(tableTags.begin());
// calc total size for font, save sizes
SkTDArray<size_t> tableSizes;
size_t totalSize = sizeof(SkSFNTHeader) + sizeof(SkSFNTHeader::TableDirectoryEntry) * numTables;
for (int tableIndex = 0; tableIndex < numTables; ++tableIndex) {
size_t tableSize = this->getTableSize(tableTags[tableIndex]);
totalSize += (tableSize + 3) & ~3;
*tableSizes.append() = tableSize;
}
// reserve memory for stream, and zero it (tables must be zero padded)
SkMemoryStream* stream = new SkMemoryStream(totalSize);
char* dataStart = (char*)stream->getMemoryBase();
sk_bzero(dataStart, totalSize);
char* dataPtr = dataStart;
// compute font header entries
uint16_t entrySelector = 0;
uint16_t searchRange = 1;
while (searchRange < numTables >> 1) {
entrySelector++;
searchRange <<= 1;
}
searchRange <<= 4;
uint16_t rangeShift = (numTables << 4) - searchRange;
// write font header
SkSFNTHeader* header = (SkSFNTHeader*)dataPtr;
header->fontType = fontType;
header->numTables = SkEndian_SwapBE16(numTables);
header->searchRange = SkEndian_SwapBE16(searchRange);
header->entrySelector = SkEndian_SwapBE16(entrySelector);
header->rangeShift = SkEndian_SwapBE16(rangeShift);
dataPtr += sizeof(SkSFNTHeader);
// write tables
SkSFNTHeader::TableDirectoryEntry* entry = (SkSFNTHeader::TableDirectoryEntry*)dataPtr;
dataPtr += sizeof(SkSFNTHeader::TableDirectoryEntry) * numTables;
for (int tableIndex = 0; tableIndex < numTables; ++tableIndex) {
size_t tableSize = tableSizes[tableIndex];
this->getTableData(tableTags[tableIndex], 0, tableSize, dataPtr);
entry->tag = SkEndian_SwapBE32(tableTags[tableIndex]);
entry->checksum = SkEndian_SwapBE32(SkOTUtils::CalcTableChecksum((SK_OT_ULONG*)dataPtr,
tableSize));
entry->offset = SkEndian_SwapBE32(SkToU32(dataPtr - dataStart));
entry->logicalLength = SkEndian_SwapBE32(SkToU32(tableSize));
dataPtr += (tableSize + 3) & ~3;
++entry;
}
return stream;
}
///////////////////////////////////////////////////////////////////////////////
///////////////////////////////////////////////////////////////////////////////
int SkTypeface_Mac::onGetUPEM() const {
AutoCFRelease<CGFontRef> cgFont(CTFontCopyGraphicsFont(fFontRef, NULL));
return CGFontGetUnitsPerEm(cgFont);
}
SkTypeface::LocalizedStrings* SkTypeface_Mac::onCreateFamilyNameIterator() const {
SkTypeface::LocalizedStrings* nameIter =
SkOTUtils::LocalizedStrings_NameTable::CreateForFamilyNames(*this);
if (NULL == nameIter) {
AutoCFRelease<CFStringRef> cfLanguage;
AutoCFRelease<CFStringRef> cfFamilyName(
CTFontCopyLocalizedName(fFontRef, kCTFontFamilyNameKey, &cfLanguage));
SkString skLanguage;
SkString skFamilyName;
if (cfLanguage.get()) {
CFStringToSkString(cfLanguage.get(), &skLanguage);
} else {
skLanguage = "und"; //undetermined
}
if (cfFamilyName.get()) {
CFStringToSkString(cfFamilyName.get(), &skFamilyName);
}
nameIter = new SkOTUtils::LocalizedStrings_SingleName(skFamilyName, skLanguage);
}
return nameIter;
}
// If, as is the case with web fonts, the CTFont data isn't available,
// the CGFont data may work. While the CGFont may always provide the
// right result, leave the CTFont code path to minimize disruption.
static CFDataRef copyTableFromFont(CTFontRef ctFont, SkFontTableTag tag) {
CFDataRef data = CTFontCopyTable(ctFont, (CTFontTableTag) tag,
kCTFontTableOptionNoOptions);
if (NULL == data) {
AutoCFRelease<CGFontRef> cgFont(CTFontCopyGraphicsFont(ctFont, NULL));
data = CGFontCopyTableForTag(cgFont, tag);
}
return data;
}
int SkTypeface_Mac::onGetTableTags(SkFontTableTag tags[]) const {
AutoCFRelease<CFArrayRef> cfArray(CTFontCopyAvailableTables(fFontRef,
kCTFontTableOptionNoOptions));
if (NULL == cfArray) {
return 0;
}
int count = SkToInt(CFArrayGetCount(cfArray));
if (tags) {
for (int i = 0; i < count; ++i) {
uintptr_t fontTag = reinterpret_cast<uintptr_t>(CFArrayGetValueAtIndex(cfArray, i));
tags[i] = static_cast<SkFontTableTag>(fontTag);
}
}
return count;
}
size_t SkTypeface_Mac::onGetTableData(SkFontTableTag tag, size_t offset,
size_t length, void* dstData) const {
AutoCFRelease<CFDataRef> srcData(copyTableFromFont(fFontRef, tag));
if (NULL == srcData) {
return 0;
}
size_t srcSize = CFDataGetLength(srcData);
if (offset >= srcSize) {
return 0;
}
if (length > srcSize - offset) {
length = srcSize - offset;
}
if (dstData) {
memcpy(dstData, CFDataGetBytePtr(srcData) + offset, length);
}
return length;
}
SkScalerContext* SkTypeface_Mac::onCreateScalerContext(const SkDescriptor* desc) const {
return new SkScalerContext_Mac(const_cast<SkTypeface_Mac*>(this), desc);
}
void SkTypeface_Mac::onFilterRec(SkScalerContextRec* rec) const {
if (rec->fFlags & SkScalerContext::kLCD_BGROrder_Flag ||
rec->fFlags & SkScalerContext::kLCD_Vertical_Flag)
{
rec->fMaskFormat = SkMask::kA8_Format;
// Render the glyphs as close as possible to what was requested.
// The above turns off subpixel rendering, but the user requested it.
// Normal hinting will cause the A8 masks to be generated from CoreGraphics subpixel masks.
// See comments below for more details.
rec->setHinting(SkPaint::kNormal_Hinting);
}
unsigned flagsWeDontSupport = SkScalerContext::kDevKernText_Flag |
SkScalerContext::kForceAutohinting_Flag |
SkScalerContext::kLCD_BGROrder_Flag |
SkScalerContext::kLCD_Vertical_Flag;
rec->fFlags &= ~flagsWeDontSupport;
bool lcdSupport = supports_LCD();
// Only two levels of hinting are supported.
// kNo_Hinting means avoid CoreGraphics outline dilation.
// kNormal_Hinting means CoreGraphics outline dilation is allowed.
// If there is no lcd support, hinting (dilation) cannot be supported.
SkPaint::Hinting hinting = rec->getHinting();
if (SkPaint::kSlight_Hinting == hinting || !lcdSupport) {
hinting = SkPaint::kNo_Hinting;
} else if (SkPaint::kFull_Hinting == hinting) {
hinting = SkPaint::kNormal_Hinting;
}
rec->setHinting(hinting);
// FIXME: lcd smoothed un-hinted rasterization unsupported.
// Tracked by http://code.google.com/p/skia/issues/detail?id=915 .
// There is no current means to honor a request for unhinted lcd,
// so arbitrarilly ignore the hinting request and honor lcd.
// Hinting and smoothing should be orthogonal, but currently they are not.
// CoreGraphics has no API to influence hinting. However, its lcd smoothed
// output is drawn from auto-dilated outlines (the amount of which is
// determined by AppleFontSmoothing). Its regular anti-aliased output is
// drawn from un-dilated outlines.
// The behavior of Skia is as follows:
// [AA][no-hint]: generate AA using CoreGraphic's AA output.
// [AA][yes-hint]: use CoreGraphic's LCD output and reduce it to a single
// channel. This matches [LCD][yes-hint] in weight.
// [LCD][no-hint]: curently unable to honor, and must pick which to respect.
// Currenly side with LCD, effectively ignoring the hinting setting.
// [LCD][yes-hint]: generate LCD using CoreGraphic's LCD output.
if (isLCDFormat(rec->fMaskFormat)) {
if (lcdSupport) {
//CoreGraphics creates 555 masks for smoothed text anyway.
rec->fMaskFormat = SkMask::kLCD16_Format;
rec->setHinting(SkPaint::kNormal_Hinting);
} else {
rec->fMaskFormat = SkMask::kA8_Format;
}
}
// Unhinted A8 masks (those not derived from LCD masks) must respect SK_GAMMA_APPLY_TO_A8.
// All other masks can use regular gamma.
if (SkMask::kA8_Format == rec->fMaskFormat && SkPaint::kNo_Hinting == hinting) {
#ifndef SK_GAMMA_APPLY_TO_A8
rec->ignorePreBlend();
#endif
} else {
//CoreGraphics dialates smoothed text as needed.
rec->setContrast(0);
}
}
// we take ownership of the ref
static const char* get_str(CFStringRef ref, SkString* str) {
if (NULL == ref) {
return NULL;
}
CFStringToSkString(ref, str);
CFSafeRelease(ref);
return str->c_str();
}
void SkTypeface_Mac::onGetFontDescriptor(SkFontDescriptor* desc,
bool* isLocalStream) const {
SkString tmpStr;
desc->setFamilyName(get_str(CTFontCopyFamilyName(fFontRef), &tmpStr));
desc->setFullName(get_str(CTFontCopyFullName(fFontRef), &tmpStr));
desc->setPostscriptName(get_str(CTFontCopyPostScriptName(fFontRef), &tmpStr));
*isLocalStream = fIsLocalStream;
}
int SkTypeface_Mac::onCharsToGlyphs(const void* chars, Encoding encoding,
uint16_t glyphs[], int glyphCount) const
{
// Undocumented behavior of CTFontGetGlyphsForCharacters with non-bmp code points:
// When a surrogate pair is detected, the glyph index used is the index of the high surrogate.
// It is documented that if a mapping is unavailable, the glyph will be set to 0.
SkAutoSTMalloc<1024, UniChar> charStorage;
const UniChar* src; // UniChar is a UTF-16 16-bit code unit.
int srcCount;
switch (encoding) {
case kUTF8_Encoding: {
const char* utf8 = reinterpret_cast<const char*>(chars);
UniChar* utf16 = charStorage.reset(2 * glyphCount);
src = utf16;
for (int i = 0; i < glyphCount; ++i) {
SkUnichar uni = SkUTF8_NextUnichar(&utf8);
utf16 += SkUTF16_FromUnichar(uni, utf16);
}
srcCount = SkToInt(utf16 - src);
break;
}
case kUTF16_Encoding: {
src = reinterpret_cast<const UniChar*>(chars);
int extra = 0;
for (int i = 0; i < glyphCount; ++i) {
if (SkUTF16_IsHighSurrogate(src[i + extra])) {
++extra;
}
}
srcCount = glyphCount + extra;
break;
}
case kUTF32_Encoding: {
const SkUnichar* utf32 = reinterpret_cast<const SkUnichar*>(chars);
UniChar* utf16 = charStorage.reset(2 * glyphCount);
src = utf16;
for (int i = 0; i < glyphCount; ++i) {
utf16 += SkUTF16_FromUnichar(utf32[i], utf16);
}
srcCount = SkToInt(utf16 - src);
break;
}
}
// If glyphs is NULL, CT still needs glyph storage for finding the first failure.
// Also, if there are any non-bmp code points, the provided 'glyphs' storage will be inadequate.
SkAutoSTMalloc<1024, uint16_t> glyphStorage;
uint16_t* macGlyphs = glyphs;
if (NULL == macGlyphs || srcCount > glyphCount) {
macGlyphs = glyphStorage.reset(srcCount);
}
bool allEncoded = CTFontGetGlyphsForCharacters(fFontRef, src, macGlyphs, srcCount);
// If there were any non-bmp, then copy and compact.
// If 'glyphs' is NULL, then compact glyphStorage in-place.
// If all are bmp and 'glyphs' is non-NULL, 'glyphs' already contains the compact glyphs.
// If some are non-bmp and 'glyphs' is non-NULL, copy and compact into 'glyphs'.
uint16_t* compactedGlyphs = glyphs;
if (NULL == compactedGlyphs) {
compactedGlyphs = macGlyphs;
}
if (srcCount > glyphCount) {
int extra = 0;
for (int i = 0; i < glyphCount; ++i) {
if (SkUTF16_IsHighSurrogate(src[i + extra])) {
++extra;
}
compactedGlyphs[i] = macGlyphs[i + extra];
}
}
if (allEncoded) {
return glyphCount;
}
// If we got false, then we need to manually look for first failure.
for (int i = 0; i < glyphCount; ++i) {
if (0 == compactedGlyphs[i]) {
return i;
}
}
// Odd to get here, as we expected CT to have returned true up front.
return glyphCount;
}
int SkTypeface_Mac::onCountGlyphs() const {
return SkToInt(CTFontGetGlyphCount(fFontRef));
}
///////////////////////////////////////////////////////////////////////////////
///////////////////////////////////////////////////////////////////////////////
#if 1
static bool find_desc_str(CTFontDescriptorRef desc, CFStringRef name, SkString* value) {
AutoCFRelease<CFStringRef> ref((CFStringRef)CTFontDescriptorCopyAttribute(desc, name));
if (NULL == ref.get()) {
return false;
}
CFStringToSkString(ref, value);
return true;
}
static bool find_dict_float(CFDictionaryRef dict, CFStringRef name, float* value) {
CFNumberRef num;
return CFDictionaryGetValueIfPresent(dict, name, (const void**)&num)
&& CFNumberIsFloatType(num)
&& CFNumberGetValue(num, kCFNumberFloatType, value);
}
#include "SkFontMgr.h"
static int unit_weight_to_fontstyle(float unit) {
float value;
if (unit < 0) {
value = 100 + (1 + unit) * 300;
} else {
value = 400 + unit * 500;
}
return sk_float_round2int(value);
}
static int unit_width_to_fontstyle(float unit) {
float value;
if (unit < 0) {
value = 1 + (1 + unit) * 4;
} else {
value = 5 + unit * 4;
}
return sk_float_round2int(value);
}
static inline int sqr(int value) {
SkASSERT(SkAbs32(value) < 0x7FFF); // check for overflow
return value * value;
}
// We normalize each axis (weight, width, italic) to be base-900
static int compute_metric(const SkFontStyle& a, const SkFontStyle& b) {
return sqr(a.weight() - b.weight()) +
sqr((a.width() - b.width()) * 100) +
sqr((a.isItalic() != b.isItalic()) * 900);
}
static SkFontStyle desc2fontstyle(CTFontDescriptorRef desc) {
AutoCFRelease<CFDictionaryRef> dict(
(CFDictionaryRef)CTFontDescriptorCopyAttribute(desc,
kCTFontTraitsAttribute));
if (NULL == dict.get()) {
return SkFontStyle();
}
float weight, width, slant;
if (!find_dict_float(dict, kCTFontWeightTrait, &weight)) {
weight = 0;
}
if (!find_dict_float(dict, kCTFontWidthTrait, &width)) {
width = 0;
}
if (!find_dict_float(dict, kCTFontSlantTrait, &slant)) {
slant = 0;
}
return SkFontStyle(unit_weight_to_fontstyle(weight),
unit_width_to_fontstyle(width),
slant ? SkFontStyle::kItalic_Slant
: SkFontStyle::kUpright_Slant);
}
struct NameFontStyleRec {
SkString fFamilyName;
SkFontStyle fFontStyle;
};
static bool nameFontStyleProc(SkTypeface* face, SkTypeface::Style,
void* ctx) {
SkTypeface_Mac* macFace = (SkTypeface_Mac*)face;
const NameFontStyleRec* rec = (const NameFontStyleRec*)ctx;
return macFace->fFontStyle == rec->fFontStyle &&
macFace->fName == rec->fFamilyName;
}
static SkTypeface* createFromDesc(CFStringRef cfFamilyName,
CTFontDescriptorRef desc) {
NameFontStyleRec rec;
CFStringToSkString(cfFamilyName, &rec.fFamilyName);
rec.fFontStyle = desc2fontstyle(desc);
SkTypeface* face = SkTypefaceCache::FindByProcAndRef(nameFontStyleProc,
&rec);
if (face) {
return face;
}
AutoCFRelease<CFDictionaryRef> fontFamilyNameDictionary(
CFDictionaryCreate(kCFAllocatorDefault,
(const void**)&kCTFontFamilyNameAttribute, (const void**)&cfFamilyName,
1, &kCFTypeDictionaryKeyCallBacks, &kCFTypeDictionaryValueCallBacks));
AutoCFRelease<CTFontDescriptorRef> fontDescriptor(
CTFontDescriptorCreateWithAttributes(fontFamilyNameDictionary));
AutoCFRelease<CTFontRef> ctNamed(CTFontCreateWithFontDescriptor(fontDescriptor, 0, NULL));
CTFontRef ctFont = CTFontCreateCopyWithAttributes(ctNamed, 1, NULL, desc);
if (NULL == ctFont) {
return NULL;
}
SkString str;
CFStringToSkString(cfFamilyName, &str);
bool isFixedPitch;
(void)computeStyleBits(ctFont, &isFixedPitch);
SkFontID fontID = CTFontRef_to_SkFontID(ctFont);
face = SkNEW_ARGS(SkTypeface_Mac, (rec.fFontStyle, fontID, isFixedPitch,
ctFont, str.c_str(), false));
SkTypefaceCache::Add(face, face->style());
return face;
}
class SkFontStyleSet_Mac : public SkFontStyleSet {
public:
SkFontStyleSet_Mac(CFStringRef familyName, CTFontDescriptorRef desc)
: fArray(CTFontDescriptorCreateMatchingFontDescriptors(desc, NULL))
, fFamilyName(familyName)
, fCount(0) {
CFRetain(familyName);
if (NULL == fArray) {
fArray = CFArrayCreate(NULL, NULL, 0, NULL);
}
fCount = SkToInt(CFArrayGetCount(fArray));
}
virtual ~SkFontStyleSet_Mac() {
CFRelease(fArray);
CFRelease(fFamilyName);
}
virtual int count() SK_OVERRIDE {
return fCount;
}
virtual void getStyle(int index, SkFontStyle* style,
SkString* name) SK_OVERRIDE {
SkASSERT((unsigned)index < (unsigned)fCount);
CTFontDescriptorRef desc = (CTFontDescriptorRef)CFArrayGetValueAtIndex(fArray, index);
if (style) {
*style = desc2fontstyle(desc);
}
if (name) {
if (!find_desc_str(desc, kCTFontStyleNameAttribute, name)) {
name->reset();
}
}
}
virtual SkTypeface* createTypeface(int index) SK_OVERRIDE {
SkASSERT((unsigned)index < (unsigned)CFArrayGetCount(fArray));
CTFontDescriptorRef desc = (CTFontDescriptorRef)CFArrayGetValueAtIndex(fArray, index);
return createFromDesc(fFamilyName, desc);
}
virtual SkTypeface* matchStyle(const SkFontStyle& pattern) SK_OVERRIDE {
if (0 == fCount) {
return NULL;
}
return createFromDesc(fFamilyName, findMatchingDesc(pattern));
}
private:
CFArrayRef fArray;
CFStringRef fFamilyName;
int fCount;
CTFontDescriptorRef findMatchingDesc(const SkFontStyle& pattern) const {
int bestMetric = SK_MaxS32;
CTFontDescriptorRef bestDesc = NULL;
for (int i = 0; i < fCount; ++i) {
CTFontDescriptorRef desc = (CTFontDescriptorRef)CFArrayGetValueAtIndex(fArray, i);
int metric = compute_metric(pattern, desc2fontstyle(desc));
if (0 == metric) {
return desc;
}
if (metric < bestMetric) {
bestMetric = metric;
bestDesc = desc;
}
}
SkASSERT(bestDesc);
return bestDesc;
}
};
class SkFontMgr_Mac : public SkFontMgr {
CFArrayRef fNames;
int fCount;
CFStringRef stringAt(int index) const {
SkASSERT((unsigned)index < (unsigned)fCount);
return (CFStringRef)CFArrayGetValueAtIndex(fNames, index);
}
static SkFontStyleSet* CreateSet(CFStringRef cfFamilyName) {
AutoCFRelease<CFMutableDictionaryRef> cfAttr(
CFDictionaryCreateMutable(kCFAllocatorDefault, 0,
&kCFTypeDictionaryKeyCallBacks,
&kCFTypeDictionaryValueCallBacks));
CFDictionaryAddValue(cfAttr, kCTFontFamilyNameAttribute, cfFamilyName);
AutoCFRelease<CTFontDescriptorRef> desc(
CTFontDescriptorCreateWithAttributes(cfAttr));
return SkNEW_ARGS(SkFontStyleSet_Mac, (cfFamilyName, desc));
}
public:
SkFontMgr_Mac()
: fNames(SkCTFontManagerCopyAvailableFontFamilyNames())
, fCount(fNames ? SkToInt(CFArrayGetCount(fNames)) : 0) {}
virtual ~SkFontMgr_Mac() {
CFSafeRelease(fNames);
}
protected:
virtual int onCountFamilies() const SK_OVERRIDE {
return fCount;
}
virtual void onGetFamilyName(int index, SkString* familyName) const SK_OVERRIDE {
if ((unsigned)index < (unsigned)fCount) {
CFStringToSkString(this->stringAt(index), familyName);
} else {
familyName->reset();
}
}
virtual SkFontStyleSet* onCreateStyleSet(int index) const SK_OVERRIDE {
if ((unsigned)index >= (unsigned)fCount) {
return NULL;
}
return CreateSet(this->stringAt(index));
}
virtual SkFontStyleSet* onMatchFamily(const char familyName[]) const SK_OVERRIDE {
AutoCFRelease<CFStringRef> cfName(make_CFString(familyName));
return CreateSet(cfName);
}
virtual SkTypeface* onMatchFamilyStyle(const char familyName[],
const SkFontStyle&) const SK_OVERRIDE {
return NULL;
}
virtual SkTypeface* onMatchFaceStyle(const SkTypeface* familyMember,
const SkFontStyle&) const SK_OVERRIDE {
return NULL;
}
virtual SkTypeface* onCreateFromData(SkData* data,
int ttcIndex) const SK_OVERRIDE {
AutoCFRelease<CGDataProviderRef> pr(SkCreateDataProviderFromData(data));
if (NULL == pr) {
return NULL;
}
return create_from_dataProvider(pr);
}
virtual SkTypeface* onCreateFromStream(SkStream* stream,
int ttcIndex) const SK_OVERRIDE {
AutoCFRelease<CGDataProviderRef> pr(SkCreateDataProviderFromStream(stream));
if (NULL == pr) {
return NULL;
}
return create_from_dataProvider(pr);
}
virtual SkTypeface* onCreateFromFile(const char path[],
int ttcIndex) const SK_OVERRIDE {
AutoCFRelease<CGDataProviderRef> pr(CGDataProviderCreateWithFilename(path));
if (NULL == pr) {
return NULL;
}
return create_from_dataProvider(pr);
}
virtual SkTypeface* onLegacyCreateTypeface(const char familyName[],
unsigned styleBits) const SK_OVERRIDE {
return create_typeface(NULL, familyName, (SkTypeface::Style)styleBits);
}
};
///////////////////////////////////////////////////////////////////////////////
SkFontMgr* SkFontMgr::Factory() {
return SkNEW(SkFontMgr_Mac);
}
#endif