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+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*-
+ * vim: set ts=4 et sw=4 tw=80:
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef GFX_FONT_H
+#define GFX_FONT_H
+
+#include "gfxTypes.h"
+#include "gfxFontEntry.h"
+#include "nsString.h"
+#include "gfxPoint.h"
+#include "gfxPattern.h"
+#include "nsTArray.h"
+#include "nsTHashtable.h"
+#include "nsHashKeys.h"
+#include "gfxRect.h"
+#include "nsExpirationTracker.h"
+#include "gfxPlatform.h"
+#include "nsIAtom.h"
+#include "mozilla/HashFunctions.h"
+#include "nsIMemoryReporter.h"
+#include "nsIObserver.h"
+#include "mozilla/MemoryReporting.h"
+#include "mozilla/Attributes.h"
+#include <algorithm>
+#include "DrawMode.h"
+#include "nsDataHashtable.h"
+#include "harfbuzz/hb.h"
+#include "mozilla/gfx/2D.h"
+#include "nsColor.h"
+
+typedef struct _cairo cairo_t;
+typedef struct _cairo_scaled_font cairo_scaled_font_t;
+//typedef struct gr_face gr_face;
+
+#ifdef DEBUG
+#include <stdio.h>
+#endif
+
+class gfxContext;
+class gfxTextRun;
+class gfxFont;
+class gfxGlyphExtents;
+class gfxShapedText;
+class gfxShapedWord;
+class gfxSkipChars;
+class gfxMathTable;
+
+#define FONT_MAX_SIZE 2000.0
+
+#define NO_FONT_LANGUAGE_OVERRIDE 0
+
+#define SMALL_CAPS_SCALE_FACTOR 0.8
+
+// The skew factor used for synthetic-italic [oblique] fonts;
+// we use a platform-dependent value to harmonize with the platform's own APIs.
+#ifdef XP_WIN
+#define OBLIQUE_SKEW_FACTOR 0.3
+#elif defined(MOZ_WIDGET_GTK)
+#define OBLIQUE_SKEW_FACTOR 0.2
+#else
+#define OBLIQUE_SKEW_FACTOR 0.25
+#endif
+
+struct gfxTextRunDrawCallbacks;
+
+namespace mozilla {
+class SVGContextPaint;
+namespace gfx {
+class GlyphRenderingOptions;
+} // namespace gfx
+} // namespace mozilla
+
+struct gfxFontStyle {
+ gfxFontStyle();
+ gfxFontStyle(uint8_t aStyle, uint16_t aWeight, int16_t aStretch,
+ gfxFloat aSize, nsIAtom *aLanguage, bool aExplicitLanguage,
+ float aSizeAdjust, bool aSystemFont,
+ bool aPrinterFont,
+ bool aWeightSynthesis, bool aStyleSynthesis,
+ const nsString& aLanguageOverride);
+ gfxFontStyle(const gfxFontStyle& aStyle);
+
+ // the language (may be an internal langGroup code rather than an actual
+ // language code) specified in the document or element's lang property,
+ // or inferred from the charset
+ RefPtr<nsIAtom> language;
+
+ // Features are composed of (1) features from style rules (2) features
+ // from feature setttings rules and (3) family-specific features. (1) and
+ // (3) are guaranteed to be mutually exclusive
+
+ // custom opentype feature settings
+ nsTArray<gfxFontFeature> featureSettings;
+
+ // Some font-variant property values require font-specific settings
+ // defined via @font-feature-values rules. These are resolved after
+ // font matching occurs.
+
+ // -- list of value tags for specific alternate features
+ nsTArray<gfxAlternateValue> alternateValues;
+
+ // -- object used to look these up once the font is matched
+ RefPtr<gfxFontFeatureValueSet> featureValueLookup;
+
+ // The logical size of the font, in pixels
+ gfxFloat size;
+
+ // The aspect-value (ie., the ratio actualsize:actualxheight) that any
+ // actual physical font created from this font structure must have when
+ // rendering or measuring a string. A value of -1.0 means no adjustment
+ // needs to be done; otherwise the value must be nonnegative.
+ float sizeAdjust;
+
+ // baseline offset, used when simulating sub/superscript glyphs
+ float baselineOffset;
+
+ // Language system tag, to override document language;
+ // an OpenType "language system" tag represented as a 32-bit integer
+ // (see http://www.microsoft.com/typography/otspec/languagetags.htm).
+ // Normally 0, so font rendering will use the document or element language
+ // (see above) to control any language-specific rendering, but the author
+ // can override this for cases where the options implemented in the font
+ // do not directly match the actual language. (E.g. lang may be Macedonian,
+ // but the font in use does not explicitly support this; the author can
+ // use font-language-override to request the Serbian option in the font
+ // in order to get correct glyph shapes.)
+ uint32_t languageOverride;
+
+ // The weight of the font: 100, 200, ... 900.
+ uint16_t weight;
+
+ // The stretch of the font (the sum of various NS_FONT_STRETCH_*
+ // constants; see gfxFontConstants.h).
+ int8_t stretch;
+
+ // Say that this font is a system font and therefore does not
+ // require certain fixup that we do for fonts from untrusted
+ // sources.
+ bool systemFont : 1;
+
+ // Say that this font is used for print or print preview.
+ bool printerFont : 1;
+
+ // Used to imitate -webkit-font-smoothing: antialiased
+ bool useGrayscaleAntialiasing : 1;
+
+ // The style of font (normal, italic, oblique)
+ uint8_t style : 2;
+
+ // Whether synthetic styles are allowed
+ bool allowSyntheticWeight : 1;
+ bool allowSyntheticStyle : 1;
+
+ // some variant features require fallback which complicates the shaping
+ // code, so set up a bool to indicate when shaping with fallback is needed
+ bool noFallbackVariantFeatures : 1;
+
+ // whether the |language| field comes from explicit lang tagging in the
+ // document, or was inferred from charset/system locale
+ bool explicitLanguage : 1;
+
+ // caps variant (small-caps, petite-caps, etc.)
+ uint8_t variantCaps;
+
+ // sub/superscript variant
+ uint8_t variantSubSuper;
+
+ // Return the final adjusted font size for the given aspect ratio.
+ // Not meant to be called when sizeAdjust = -1.0.
+ gfxFloat GetAdjustedSize(gfxFloat aspect) const {
+ NS_ASSERTION(sizeAdjust >= 0.0, "Not meant to be called when sizeAdjust = -1.0");
+ gfxFloat adjustedSize = std::max(NS_round(size*(sizeAdjust/aspect)), 1.0);
+ return std::min(adjustedSize, FONT_MAX_SIZE);
+ }
+
+ PLDHashNumber Hash() const {
+ return ((style + (systemFont << 7) +
+ (weight << 8)) + uint32_t(size*1000) + uint32_t(sizeAdjust*1000)) ^
+ nsISupportsHashKey::HashKey(language);
+ }
+
+ int8_t ComputeWeight() const;
+
+ // Adjust this style to simulate sub/superscript (as requested in the
+ // variantSubSuper field) using size and baselineOffset instead.
+ void AdjustForSubSuperscript(int32_t aAppUnitsPerDevPixel);
+
+ bool Equals(const gfxFontStyle& other) const {
+ return
+ (*reinterpret_cast<const uint64_t*>(&size) ==
+ *reinterpret_cast<const uint64_t*>(&other.size)) &&
+ (style == other.style) &&
+ (variantCaps == other.variantCaps) &&
+ (variantSubSuper == other.variantSubSuper) &&
+ (allowSyntheticWeight == other.allowSyntheticWeight) &&
+ (allowSyntheticStyle == other.allowSyntheticStyle) &&
+ (systemFont == other.systemFont) &&
+ (printerFont == other.printerFont) &&
+ (useGrayscaleAntialiasing == other.useGrayscaleAntialiasing) &&
+ (explicitLanguage == other.explicitLanguage) &&
+ (weight == other.weight) &&
+ (stretch == other.stretch) &&
+ (language == other.language) &&
+ (baselineOffset == other.baselineOffset) &&
+ (*reinterpret_cast<const uint32_t*>(&sizeAdjust) ==
+ *reinterpret_cast<const uint32_t*>(&other.sizeAdjust)) &&
+ (featureSettings == other.featureSettings) &&
+ (languageOverride == other.languageOverride) &&
+ (alternateValues == other.alternateValues) &&
+ (featureValueLookup == other.featureValueLookup);
+ }
+
+ static void ParseFontFeatureSettings(const nsString& aFeatureString,
+ nsTArray<gfxFontFeature>& aFeatures);
+
+ static uint32_t ParseFontLanguageOverride(const nsString& aLangTag);
+};
+
+struct gfxTextRange {
+ enum {
+ // flags for recording the kind of font-matching that was used
+ kFontGroup = 0x0001,
+ kPrefsFallback = 0x0002,
+ kSystemFallback = 0x0004
+ };
+ gfxTextRange(uint32_t aStart, uint32_t aEnd,
+ gfxFont* aFont, uint8_t aMatchType,
+ uint16_t aOrientation)
+ : start(aStart),
+ end(aEnd),
+ font(aFont),
+ matchType(aMatchType),
+ orientation(aOrientation)
+ { }
+ uint32_t Length() const { return end - start; }
+ uint32_t start, end;
+ RefPtr<gfxFont> font;
+ uint8_t matchType;
+ uint16_t orientation;
+};
+
+
+/**
+ * Font cache design:
+ *
+ * The mFonts hashtable contains most fonts, indexed by (gfxFontEntry*, style).
+ * It does not add a reference to the fonts it contains.
+ * When a font's refcount decreases to zero, instead of deleting it we
+ * add it to our expiration tracker.
+ * The expiration tracker tracks fonts with zero refcount. After a certain
+ * period of time, such fonts expire and are deleted.
+ *
+ * We're using 3 generations with a ten-second generation interval, so
+ * zero-refcount fonts will be deleted 20-30 seconds after their refcount
+ * goes to zero, if timer events fire in a timely manner.
+ *
+ * The font cache also handles timed expiration of cached ShapedWords
+ * for "persistent" fonts: it has a repeating timer, and notifies
+ * each cached font to "age" its shaped words. The words will be released
+ * by the fonts if they get aged three times without being re-used in the
+ * meantime.
+ *
+ * Note that the ShapedWord timeout is much larger than the font timeout,
+ * so that in the case of a short-lived font, we'll discard the gfxFont
+ * completely, with all its words, and avoid the cost of aging the words
+ * individually. That only happens with longer-lived fonts.
+ */
+struct FontCacheSizes {
+ FontCacheSizes()
+ : mFontInstances(0), mShapedWords(0)
+ { }
+
+ size_t mFontInstances; // memory used by instances of gfxFont subclasses
+ size_t mShapedWords; // memory used by the per-font shapedWord caches
+};
+
+class gfxFontCache final : public nsExpirationTracker<gfxFont,3> {
+public:
+ enum {
+ FONT_TIMEOUT_SECONDS = 10,
+ SHAPED_WORD_TIMEOUT_SECONDS = 60
+ };
+
+ gfxFontCache();
+ ~gfxFontCache();
+
+ /*
+ * Get the global gfxFontCache. You must call Init() before
+ * calling this method --- the result will not be null.
+ */
+ static gfxFontCache* GetCache() {
+ return gGlobalCache;
+ }
+
+ static nsresult Init();
+ // It's OK to call this even if Init() has not been called.
+ static void Shutdown();
+
+ // Look up a font in the cache. Returns an addrefed pointer, or null
+ // if there's nothing matching in the cache
+ already_AddRefed<gfxFont>
+ Lookup(const gfxFontEntry* aFontEntry,
+ const gfxFontStyle* aStyle,
+ const gfxCharacterMap* aUnicodeRangeMap);
+
+ // We created a new font (presumably because Lookup returned null);
+ // put it in the cache. The font's refcount should be nonzero. It is
+ // allowable to add a new font even if there is one already in the
+ // cache with the same key; we'll forget about the old one.
+ void AddNew(gfxFont *aFont);
+
+ // The font's refcount has gone to zero; give ownership of it to
+ // the cache. We delete it if it's not acquired again after a certain
+ // amount of time.
+ void NotifyReleased(gfxFont *aFont);
+
+ // This gets called when the timeout has expired on a zero-refcount
+ // font; we just delete it.
+ virtual void NotifyExpired(gfxFont *aFont) override;
+
+ // Cleans out the hashtable and removes expired fonts waiting for cleanup.
+ // Other gfxFont objects may be still in use but they will be pushed
+ // into the expiration queues and removed.
+ void Flush() {
+ mFonts.Clear();
+ AgeAllGenerations();
+ }
+
+ void FlushShapedWordCaches();
+
+ void AddSizeOfExcludingThis(mozilla::MallocSizeOf aMallocSizeOf,
+ FontCacheSizes* aSizes) const;
+ void AddSizeOfIncludingThis(mozilla::MallocSizeOf aMallocSizeOf,
+ FontCacheSizes* aSizes) const;
+
+protected:
+ class MemoryReporter final : public nsIMemoryReporter
+ {
+ ~MemoryReporter() {}
+ public:
+ NS_DECL_ISUPPORTS
+ NS_DECL_NSIMEMORYREPORTER
+ };
+
+ // Observer for notifications that the font cache cares about
+ class Observer final
+ : public nsIObserver
+ {
+ ~Observer() {}
+ public:
+ NS_DECL_ISUPPORTS
+ NS_DECL_NSIOBSERVER
+ };
+
+ void DestroyFont(gfxFont *aFont);
+
+ static gfxFontCache *gGlobalCache;
+
+ struct Key {
+ const gfxFontEntry* mFontEntry;
+ const gfxFontStyle* mStyle;
+ const gfxCharacterMap* mUnicodeRangeMap;
+ Key(const gfxFontEntry* aFontEntry, const gfxFontStyle* aStyle,
+ const gfxCharacterMap* aUnicodeRangeMap)
+ : mFontEntry(aFontEntry), mStyle(aStyle),
+ mUnicodeRangeMap(aUnicodeRangeMap)
+ {}
+ };
+
+ class HashEntry : public PLDHashEntryHdr {
+ public:
+ typedef const Key& KeyType;
+ typedef const Key* KeyTypePointer;
+
+ // When constructing a new entry in the hashtable, we'll leave this
+ // blank. The caller of Put() will fill this in.
+ explicit HashEntry(KeyTypePointer aStr) : mFont(nullptr) { }
+ HashEntry(const HashEntry& toCopy) : mFont(toCopy.mFont) { }
+ ~HashEntry() { }
+
+ bool KeyEquals(const KeyTypePointer aKey) const;
+ static KeyTypePointer KeyToPointer(KeyType aKey) { return &aKey; }
+ static PLDHashNumber HashKey(const KeyTypePointer aKey) {
+ return mozilla::HashGeneric(aKey->mStyle->Hash(), aKey->mFontEntry,
+ aKey->mUnicodeRangeMap);
+ }
+ enum { ALLOW_MEMMOVE = true };
+
+ gfxFont* mFont;
+ };
+
+ nsTHashtable<HashEntry> mFonts;
+
+ static void WordCacheExpirationTimerCallback(nsITimer* aTimer, void* aCache);
+ nsCOMPtr<nsITimer> mWordCacheExpirationTimer;
+};
+
+class gfxTextPerfMetrics {
+public:
+
+ struct TextCounts {
+ uint32_t numContentTextRuns;
+ uint32_t numChromeTextRuns;
+ uint32_t numChars;
+ uint32_t maxTextRunLen;
+ uint32_t wordCacheSpaceRules;
+ uint32_t wordCacheLong;
+ uint32_t wordCacheHit;
+ uint32_t wordCacheMiss;
+ uint32_t fallbackPrefs;
+ uint32_t fallbackSystem;
+ uint32_t textrunConst;
+ uint32_t textrunDestr;
+ uint32_t genericLookups;
+ };
+
+ uint32_t reflowCount;
+
+ // counts per reflow operation
+ TextCounts current;
+
+ // totals for the lifetime of a document
+ TextCounts cumulative;
+
+ gfxTextPerfMetrics() {
+ memset(this, 0, sizeof(gfxTextPerfMetrics));
+ }
+
+ // add current totals to cumulative ones
+ void Accumulate() {
+ if (current.numChars == 0) {
+ return;
+ }
+ cumulative.numContentTextRuns += current.numContentTextRuns;
+ cumulative.numChromeTextRuns += current.numChromeTextRuns;
+ cumulative.numChars += current.numChars;
+ if (current.maxTextRunLen > cumulative.maxTextRunLen) {
+ cumulative.maxTextRunLen = current.maxTextRunLen;
+ }
+ cumulative.wordCacheSpaceRules += current.wordCacheSpaceRules;
+ cumulative.wordCacheLong += current.wordCacheLong;
+ cumulative.wordCacheHit += current.wordCacheHit;
+ cumulative.wordCacheMiss += current.wordCacheMiss;
+ cumulative.fallbackPrefs += current.fallbackPrefs;
+ cumulative.fallbackSystem += current.fallbackSystem;
+ cumulative.textrunConst += current.textrunConst;
+ cumulative.textrunDestr += current.textrunDestr;
+ cumulative.genericLookups += current.genericLookups;
+ memset(&current, 0, sizeof(current));
+ }
+};
+
+class gfxTextRunFactory {
+ NS_INLINE_DECL_REFCOUNTING(gfxTextRunFactory)
+
+public:
+ typedef mozilla::gfx::DrawTarget DrawTarget;
+
+ // Flags in the mask 0xFFFF0000 are reserved for textrun clients
+ // Flags in the mask 0x0000F000 are reserved for per-platform fonts
+ // Flags in the mask 0x00000FFF are set by the textrun creator.
+ enum {
+ CACHE_TEXT_FLAGS = 0xF0000000,
+ USER_TEXT_FLAGS = 0x0FFF0000,
+ TEXTRUN_TEXT_FLAGS = 0x0000FFFF,
+ SETTABLE_FLAGS = CACHE_TEXT_FLAGS | USER_TEXT_FLAGS,
+
+ /**
+ * When set, the text string pointer used to create the text run
+ * is guaranteed to be available during the lifetime of the text run.
+ */
+ TEXT_IS_PERSISTENT = 0x0001,
+ /**
+ * When set, the text is known to be all-ASCII (< 128).
+ */
+ TEXT_IS_ASCII = 0x0002,
+ /**
+ * When set, the text is RTL.
+ */
+ TEXT_IS_RTL = 0x0004,
+ /**
+ * When set, spacing is enabled and the textrun needs to call GetSpacing
+ * on the spacing provider.
+ */
+ TEXT_ENABLE_SPACING = 0x0008,
+ /**
+ * When set, GetHyphenationBreaks may return true for some character
+ * positions, otherwise it will always return false for all characters.
+ */
+ TEXT_ENABLE_HYPHEN_BREAKS = 0x0010,
+ /**
+ * When set, the text has no characters above 255 and it is stored
+ * in the textrun in 8-bit format.
+ */
+ TEXT_IS_8BIT = 0x0020,
+ /**
+ * When set, the RunMetrics::mBoundingBox field will be initialized
+ * properly based on glyph extents, in particular, glyph extents that
+ * overflow the standard font-box (the box defined by the ascent, descent
+ * and advance width of the glyph). When not set, it may just be the
+ * standard font-box even if glyphs overflow.
+ */
+ TEXT_NEED_BOUNDING_BOX = 0x0040,
+ /**
+ * When set, optional ligatures are disabled. Ligatures that are
+ * required for legible text should still be enabled.
+ */
+ TEXT_DISABLE_OPTIONAL_LIGATURES = 0x0080,
+ /**
+ * When set, the textrun should favour speed of construction over
+ * quality. This may involve disabling ligatures and/or kerning or
+ * other effects.
+ */
+ TEXT_OPTIMIZE_SPEED = 0x0100,
+ /**
+ * For internal use by the memory reporter when accounting for
+ * storage used by textruns.
+ * Because the reporter may visit each textrun multiple times while
+ * walking the frame trees and textrun cache, it needs to mark
+ * textruns that have been seen so as to avoid multiple-accounting.
+ */
+ TEXT_RUN_SIZE_ACCOUNTED = 0x0200,
+ /**
+ * When set, the textrun should discard control characters instead of
+ * turning them into hexboxes.
+ */
+ TEXT_HIDE_CONTROL_CHARACTERS = 0x0400,
+
+ /**
+ * Field for orientation of the textrun and glyphs within it.
+ * Possible values of the TEXT_ORIENT_MASK field:
+ * TEXT_ORIENT_HORIZONTAL
+ * TEXT_ORIENT_VERTICAL_UPRIGHT
+ * TEXT_ORIENT_VERTICAL_SIDEWAYS_RIGHT
+ * TEXT_ORIENT_VERTICAL_SIDEWAYS_LEFT
+ * TEXT_ORIENT_VERTICAL_MIXED
+ * For all VERTICAL settings, the x and y coordinates of glyph
+ * positions are exchanged, so that simple advances are vertical.
+ *
+ * The MIXED value indicates vertical textRuns for which the CSS
+ * text-orientation property is 'mixed', but is never used for
+ * individual glyphRuns; it will be resolved to either UPRIGHT
+ * or SIDEWAYS_RIGHT according to the UTR50 properties of the
+ * characters, and separate glyphRuns created for the resulting
+ * glyph orientations.
+ */
+ TEXT_ORIENT_MASK = 0xF000,
+ TEXT_ORIENT_HORIZONTAL = 0x0000,
+ TEXT_ORIENT_VERTICAL_UPRIGHT = 0x1000,
+ TEXT_ORIENT_VERTICAL_SIDEWAYS_RIGHT = 0x2000,
+ TEXT_ORIENT_VERTICAL_SIDEWAYS_LEFT = 0x4000,
+ TEXT_ORIENT_VERTICAL_MIXED = 0x8000,
+
+ /**
+ * nsTextFrameThebes sets these, but they're defined here rather than
+ * in nsTextFrameUtils.h because ShapedWord creation/caching also needs
+ * to check the _INCOMING flag
+ */
+ TEXT_TRAILING_ARABICCHAR = 0x20000000,
+ /**
+ * When set, the previous character for this textrun was an Arabic
+ * character. This is used for the context detection necessary for
+ * bidi.numeral implementation.
+ */
+ TEXT_INCOMING_ARABICCHAR = 0x40000000,
+
+ // Set if the textrun should use the OpenType 'math' script.
+ TEXT_USE_MATH_SCRIPT = 0x80000000,
+ };
+
+ /**
+ * This record contains all the parameters needed to initialize a textrun.
+ */
+ struct Parameters {
+ // Shape text params suggesting where the textrun will be rendered
+ DrawTarget *mDrawTarget;
+ // Pointer to arbitrary user data (which should outlive the textrun)
+ void *mUserData;
+ // A description of which characters have been stripped from the original
+ // DOM string to produce the characters in the textrun. May be null
+ // if that information is not relevant.
+ gfxSkipChars *mSkipChars;
+ // A list of where linebreaks are currently placed in the textrun. May
+ // be null if mInitialBreakCount is zero.
+ uint32_t *mInitialBreaks;
+ uint32_t mInitialBreakCount;
+ // The ratio to use to convert device pixels to application layout units
+ int32_t mAppUnitsPerDevUnit;
+ };
+
+protected:
+ // Protected destructor, to discourage deletion outside of Release():
+ virtual ~gfxTextRunFactory() {}
+};
+
+/**
+ * gfxFontShaper
+ *
+ * This class implements text shaping (character to glyph mapping and
+ * glyph layout). There is a gfxFontShaper subclass for each text layout
+ * technology (uniscribe, core text, harfbuzz,....) we support.
+ *
+ * The shaper is responsible for setting up glyph data in gfxTextRuns.
+ *
+ * A generic, platform-independent shaper relies only on the standard
+ * gfxFont interface and can work with any concrete subclass of gfxFont.
+ *
+ * Platform-specific implementations designed to interface to platform
+ * shaping APIs such as Uniscribe or CoreText may rely on features of a
+ * specific font subclass to access native font references
+ * (such as CTFont, HFONT, DWriteFont, etc).
+ */
+
+class gfxFontShaper {
+public:
+ typedef mozilla::gfx::DrawTarget DrawTarget;
+ typedef mozilla::unicode::Script Script;
+
+ explicit gfxFontShaper(gfxFont *aFont)
+ : mFont(aFont)
+ {
+ NS_ASSERTION(aFont, "shaper requires a valid font!");
+ }
+
+ virtual ~gfxFontShaper() { }
+
+ // Shape a piece of text and store the resulting glyph data into
+ // aShapedText. Parameters aOffset/aLength indicate the range of
+ // aShapedText to be updated; aLength is also the length of aText.
+ virtual bool ShapeText(DrawTarget *aDrawTarget,
+ const char16_t *aText,
+ uint32_t aOffset,
+ uint32_t aLength,
+ Script aScript,
+ bool aVertical,
+ gfxShapedText *aShapedText) = 0;
+
+ gfxFont *GetFont() const { return mFont; }
+
+ static void
+ MergeFontFeatures(const gfxFontStyle *aStyle,
+ const nsTArray<gfxFontFeature>& aFontFeatures,
+ bool aDisableLigatures,
+ const nsAString& aFamilyName,
+ bool aAddSmallCaps,
+ void (*aHandleFeature)(const uint32_t&,
+ uint32_t&, void*),
+ void* aHandleFeatureData);
+
+protected:
+ // Work out whether cairo will snap inter-glyph spacing to pixels.
+ static void GetRoundOffsetsToPixels(DrawTarget* aDrawTarget,
+ bool* aRoundX, bool* aRoundY);
+
+ // the font this shaper is working with. The font owns a UniquePtr reference
+ // to this object, and will destroy it before it dies. Thus, mFont will always
+ // be valid.
+ gfxFont* MOZ_NON_OWNING_REF mFont;
+};
+
+
+/*
+ * gfxShapedText is an abstract superclass for gfxShapedWord and gfxTextRun.
+ * These are objects that store a list of zero or more glyphs for each character.
+ * For each glyph we store the glyph ID, the advance, and possibly x/y-offsets.
+ * The idea is that a string is rendered by a loop that draws each glyph
+ * at its designated offset from the current point, then advances the current
+ * point by the glyph's advance in the direction of the textrun (LTR or RTL).
+ * Each glyph advance is always rounded to the nearest appunit; this ensures
+ * consistent results when dividing the text in a textrun into multiple text
+ * frames (frame boundaries are always aligned to appunits). We optimize
+ * for the case where a character has a single glyph and zero xoffset and yoffset,
+ * and the glyph ID and advance are in a reasonable range so we can pack all
+ * necessary data into 32 bits.
+ *
+ * gfxFontShaper can shape text into either a gfxShapedWord (cached by a gfxFont)
+ * or directly into a gfxTextRun (for cases where we want to shape textruns in
+ * their entirety rather than using cached words, because there may be layout
+ * features that depend on the inter-word spaces).
+ */
+class gfxShapedText
+{
+public:
+ typedef mozilla::unicode::Script Script;
+
+ gfxShapedText(uint32_t aLength, uint32_t aFlags,
+ int32_t aAppUnitsPerDevUnit)
+ : mLength(aLength)
+ , mFlags(aFlags)
+ , mAppUnitsPerDevUnit(aAppUnitsPerDevUnit)
+ { }
+
+ virtual ~gfxShapedText() { }
+
+ /**
+ * This class records the information associated with a character in the
+ * input string. It's optimized for the case where there is one glyph
+ * representing that character alone.
+ *
+ * A character can have zero or more associated glyphs. Each glyph
+ * has an advance width and an x and y offset.
+ * A character may be the start of a cluster.
+ * A character may be the start of a ligature group.
+ * A character can be "missing", indicating that the system is unable
+ * to render the character.
+ *
+ * All characters in a ligature group conceptually share all the glyphs
+ * associated with the characters in a group.
+ */
+ class CompressedGlyph {
+ public:
+ CompressedGlyph() { mValue = 0; }
+
+ enum {
+ // Indicates that a cluster and ligature group starts at this
+ // character; this character has a single glyph with a reasonable
+ // advance and zero offsets. A "reasonable" advance
+ // is one that fits in the available bits (currently 12) (specified
+ // in appunits).
+ FLAG_IS_SIMPLE_GLYPH = 0x80000000U,
+
+ // Indicates whether a linebreak is allowed before this character;
+ // this is a two-bit field that holds a FLAG_BREAK_TYPE_xxx value
+ // indicating the kind of linebreak (if any) allowed here.
+ FLAGS_CAN_BREAK_BEFORE = 0x60000000U,
+
+ FLAGS_CAN_BREAK_SHIFT = 29,
+ FLAG_BREAK_TYPE_NONE = 0,
+ FLAG_BREAK_TYPE_NORMAL = 1,
+ FLAG_BREAK_TYPE_HYPHEN = 2,
+
+ FLAG_CHAR_IS_SPACE = 0x10000000U,
+
+ // The advance is stored in appunits
+ ADVANCE_MASK = 0x0FFF0000U,
+ ADVANCE_SHIFT = 16,
+
+ GLYPH_MASK = 0x0000FFFFU,
+
+ // Non-simple glyphs may or may not have glyph data in the
+ // corresponding mDetailedGlyphs entry. They have the following
+ // flag bits:
+
+ // When NOT set, indicates that this character corresponds to a
+ // missing glyph and should be skipped (or possibly, render the character
+ // Unicode value in some special way). If there are glyphs,
+ // the mGlyphID is actually the UTF16 character code. The bit is
+ // inverted so we can memset the array to zero to indicate all missing.
+ FLAG_NOT_MISSING = 0x01,
+ FLAG_NOT_CLUSTER_START = 0x02,
+ FLAG_NOT_LIGATURE_GROUP_START = 0x04,
+
+ FLAG_CHAR_IS_TAB = 0x08,
+ FLAG_CHAR_IS_NEWLINE = 0x10,
+ // Per CSS Text Decoration Module Level 3, emphasis marks are not
+ // drawn for any character in Unicode categories Z*, Cc, Cf, and Cn
+ // which is not combined with any combining characters. This flag is
+ // set for all those characters except 0x20 whitespace.
+ FLAG_CHAR_NO_EMPHASIS_MARK = 0x20,
+ CHAR_TYPE_FLAGS_MASK = 0x38,
+
+ GLYPH_COUNT_MASK = 0x00FFFF00U,
+ GLYPH_COUNT_SHIFT = 8
+ };
+
+ // "Simple glyphs" have a simple glyph ID, simple advance and their
+ // x and y offsets are zero. Also the glyph extents do not overflow
+ // the font-box defined by the font ascent, descent and glyph advance width.
+ // These case is optimized to avoid storing DetailedGlyphs.
+
+ // Returns true if the glyph ID aGlyph fits into the compressed representation
+ static bool IsSimpleGlyphID(uint32_t aGlyph) {
+ return (aGlyph & GLYPH_MASK) == aGlyph;
+ }
+ // Returns true if the advance aAdvance fits into the compressed representation.
+ // aAdvance is in appunits.
+ static bool IsSimpleAdvance(uint32_t aAdvance) {
+ return (aAdvance & (ADVANCE_MASK >> ADVANCE_SHIFT)) == aAdvance;
+ }
+
+ bool IsSimpleGlyph() const { return (mValue & FLAG_IS_SIMPLE_GLYPH) != 0; }
+ uint32_t GetSimpleAdvance() const { return (mValue & ADVANCE_MASK) >> ADVANCE_SHIFT; }
+ uint32_t GetSimpleGlyph() const { return mValue & GLYPH_MASK; }
+
+ bool IsMissing() const { return (mValue & (FLAG_NOT_MISSING|FLAG_IS_SIMPLE_GLYPH)) == 0; }
+ bool IsClusterStart() const {
+ return (mValue & FLAG_IS_SIMPLE_GLYPH) || !(mValue & FLAG_NOT_CLUSTER_START);
+ }
+ bool IsLigatureGroupStart() const {
+ return (mValue & FLAG_IS_SIMPLE_GLYPH) || !(mValue & FLAG_NOT_LIGATURE_GROUP_START);
+ }
+ bool IsLigatureContinuation() const {
+ return (mValue & FLAG_IS_SIMPLE_GLYPH) == 0 &&
+ (mValue & (FLAG_NOT_LIGATURE_GROUP_START | FLAG_NOT_MISSING)) ==
+ (FLAG_NOT_LIGATURE_GROUP_START | FLAG_NOT_MISSING);
+ }
+
+ // Return true if the original character was a normal (breakable,
+ // trimmable) space (U+0020). Not true for other characters that
+ // may happen to map to the space glyph (U+00A0).
+ bool CharIsSpace() const {
+ return (mValue & FLAG_CHAR_IS_SPACE) != 0;
+ }
+
+ bool CharIsTab() const {
+ return !IsSimpleGlyph() && (mValue & FLAG_CHAR_IS_TAB) != 0;
+ }
+ bool CharIsNewline() const {
+ return !IsSimpleGlyph() && (mValue & FLAG_CHAR_IS_NEWLINE) != 0;
+ }
+ bool CharMayHaveEmphasisMark() const {
+ return !CharIsSpace() &&
+ (IsSimpleGlyph() || !(mValue & FLAG_CHAR_NO_EMPHASIS_MARK));
+ }
+
+ uint32_t CharTypeFlags() const {
+ return IsSimpleGlyph() ? 0 : (mValue & CHAR_TYPE_FLAGS_MASK);
+ }
+
+ void SetClusterStart(bool aIsClusterStart) {
+ NS_ASSERTION(!IsSimpleGlyph(),
+ "can't call SetClusterStart on simple glyphs");
+ if (aIsClusterStart) {
+ mValue &= ~FLAG_NOT_CLUSTER_START;
+ } else {
+ mValue |= FLAG_NOT_CLUSTER_START;
+ }
+ }
+
+ uint8_t CanBreakBefore() const {
+ return (mValue & FLAGS_CAN_BREAK_BEFORE) >> FLAGS_CAN_BREAK_SHIFT;
+ }
+ // Returns FLAGS_CAN_BREAK_BEFORE if the setting changed, 0 otherwise
+ uint32_t SetCanBreakBefore(uint8_t aCanBreakBefore) {
+ NS_ASSERTION(aCanBreakBefore <= 2,
+ "Bogus break-before value!");
+ uint32_t breakMask = (uint32_t(aCanBreakBefore) << FLAGS_CAN_BREAK_SHIFT);
+ uint32_t toggle = breakMask ^ (mValue & FLAGS_CAN_BREAK_BEFORE);
+ mValue ^= toggle;
+ return toggle;
+ }
+
+ CompressedGlyph& SetSimpleGlyph(uint32_t aAdvanceAppUnits, uint32_t aGlyph) {
+ NS_ASSERTION(IsSimpleAdvance(aAdvanceAppUnits), "Advance overflow");
+ NS_ASSERTION(IsSimpleGlyphID(aGlyph), "Glyph overflow");
+ NS_ASSERTION(!CharTypeFlags(), "Char type flags lost");
+ mValue = (mValue & (FLAGS_CAN_BREAK_BEFORE | FLAG_CHAR_IS_SPACE)) |
+ FLAG_IS_SIMPLE_GLYPH |
+ (aAdvanceAppUnits << ADVANCE_SHIFT) | aGlyph;
+ return *this;
+ }
+ CompressedGlyph& SetComplex(bool aClusterStart, bool aLigatureStart,
+ uint32_t aGlyphCount) {
+ mValue = (mValue & (FLAGS_CAN_BREAK_BEFORE | FLAG_CHAR_IS_SPACE)) |
+ FLAG_NOT_MISSING |
+ CharTypeFlags() |
+ (aClusterStart ? 0 : FLAG_NOT_CLUSTER_START) |
+ (aLigatureStart ? 0 : FLAG_NOT_LIGATURE_GROUP_START) |
+ (aGlyphCount << GLYPH_COUNT_SHIFT);
+ return *this;
+ }
+ /**
+ * Missing glyphs are treated as ligature group starts; don't mess with
+ * the cluster-start flag (see bugs 618870 and 619286).
+ */
+ CompressedGlyph& SetMissing(uint32_t aGlyphCount) {
+ mValue = (mValue & (FLAGS_CAN_BREAK_BEFORE | FLAG_NOT_CLUSTER_START |
+ FLAG_CHAR_IS_SPACE)) |
+ CharTypeFlags() |
+ (aGlyphCount << GLYPH_COUNT_SHIFT);
+ return *this;
+ }
+ uint32_t GetGlyphCount() const {
+ NS_ASSERTION(!IsSimpleGlyph(), "Expected non-simple-glyph");
+ return (mValue & GLYPH_COUNT_MASK) >> GLYPH_COUNT_SHIFT;
+ }
+
+ void SetIsSpace() {
+ mValue |= FLAG_CHAR_IS_SPACE;
+ }
+ void SetIsTab() {
+ NS_ASSERTION(!IsSimpleGlyph(), "Expected non-simple-glyph");
+ mValue |= FLAG_CHAR_IS_TAB;
+ }
+ void SetIsNewline() {
+ NS_ASSERTION(!IsSimpleGlyph(), "Expected non-simple-glyph");
+ mValue |= FLAG_CHAR_IS_NEWLINE;
+ }
+ void SetNoEmphasisMark() {
+ NS_ASSERTION(!IsSimpleGlyph(), "Expected non-simple-glyph");
+ mValue |= FLAG_CHAR_NO_EMPHASIS_MARK;
+ }
+
+ private:
+ uint32_t mValue;
+ };
+
+ // Accessor for the array of CompressedGlyph records, which will be in
+ // a different place in gfxShapedWord vs gfxTextRun
+ virtual const CompressedGlyph *GetCharacterGlyphs() const = 0;
+ virtual CompressedGlyph *GetCharacterGlyphs() = 0;
+
+ /**
+ * When the glyphs for a character don't fit into a CompressedGlyph record
+ * in SimpleGlyph format, we use an array of DetailedGlyphs instead.
+ */
+ struct DetailedGlyph {
+ /** The glyphID, or the Unicode character
+ * if this is a missing glyph */
+ uint32_t mGlyphID;
+ /** The advance, x-offset and y-offset of the glyph, in appunits
+ * mAdvance is in the text direction (RTL or LTR)
+ * mXOffset is always from left to right
+ * mYOffset is always from top to bottom */
+ int32_t mAdvance;
+ float mXOffset, mYOffset;
+ };
+
+ void SetGlyphs(uint32_t aCharIndex, CompressedGlyph aGlyph,
+ const DetailedGlyph *aGlyphs);
+
+ void SetMissingGlyph(uint32_t aIndex, uint32_t aChar, gfxFont *aFont);
+
+ void SetIsSpace(uint32_t aIndex) {
+ GetCharacterGlyphs()[aIndex].SetIsSpace();
+ }
+
+ bool HasDetailedGlyphs() const {
+ return mDetailedGlyphs != nullptr;
+ }
+
+ bool IsLigatureGroupStart(uint32_t aPos) {
+ NS_ASSERTION(aPos < GetLength(), "aPos out of range");
+ return GetCharacterGlyphs()[aPos].IsLigatureGroupStart();
+ }
+
+ // NOTE that this must not be called for a character offset that does
+ // not have any DetailedGlyph records; callers must have verified that
+ // GetCharacterGlyphs()[aCharIndex].GetGlyphCount() is greater than zero.
+ DetailedGlyph *GetDetailedGlyphs(uint32_t aCharIndex) const {
+ NS_ASSERTION(GetCharacterGlyphs() && HasDetailedGlyphs() &&
+ !GetCharacterGlyphs()[aCharIndex].IsSimpleGlyph() &&
+ GetCharacterGlyphs()[aCharIndex].GetGlyphCount() > 0,
+ "invalid use of GetDetailedGlyphs; check the caller!");
+ return mDetailedGlyphs->Get(aCharIndex);
+ }
+
+ void AdjustAdvancesForSyntheticBold(float aSynBoldOffset,
+ uint32_t aOffset, uint32_t aLength);
+
+ // Mark clusters in the CompressedGlyph records, starting at aOffset,
+ // based on the Unicode properties of the text in aString.
+ // This is also responsible to set the IsSpace flag for space characters.
+ void SetupClusterBoundaries(uint32_t aOffset,
+ const char16_t *aString,
+ uint32_t aLength);
+ // In 8-bit text, there won't actually be any clusters, but we still need
+ // the space-marking functionality.
+ void SetupClusterBoundaries(uint32_t aOffset,
+ const uint8_t *aString,
+ uint32_t aLength);
+
+ uint32_t GetFlags() const {
+ return mFlags;
+ }
+
+ bool IsVertical() const {
+ return (GetFlags() & gfxTextRunFactory::TEXT_ORIENT_MASK) !=
+ gfxTextRunFactory::TEXT_ORIENT_HORIZONTAL;
+ }
+
+ bool UseCenterBaseline() const {
+ uint32_t orient = GetFlags() & gfxTextRunFactory::TEXT_ORIENT_MASK;
+ return orient == gfxTextRunFactory::TEXT_ORIENT_VERTICAL_MIXED ||
+ orient == gfxTextRunFactory::TEXT_ORIENT_VERTICAL_UPRIGHT;
+ }
+
+ bool IsRightToLeft() const {
+ return (GetFlags() & gfxTextRunFactory::TEXT_IS_RTL) != 0;
+ }
+
+ bool IsSidewaysLeft() const {
+ return (GetFlags() & gfxTextRunFactory::TEXT_ORIENT_MASK) ==
+ gfxTextRunFactory::TEXT_ORIENT_VERTICAL_SIDEWAYS_LEFT;
+ }
+
+ // Return true if the logical inline direction is reversed compared to
+ // normal physical coordinates (i.e. if it is leftwards or upwards)
+ bool IsInlineReversed() const {
+ return IsSidewaysLeft() != IsRightToLeft();
+ }
+
+ gfxFloat GetDirection() const {
+ return IsInlineReversed() ? -1.0f : 1.0f;
+ }
+
+ bool DisableLigatures() const {
+ return (GetFlags() &
+ gfxTextRunFactory::TEXT_DISABLE_OPTIONAL_LIGATURES) != 0;
+ }
+
+ bool TextIs8Bit() const {
+ return (GetFlags() & gfxTextRunFactory::TEXT_IS_8BIT) != 0;
+ }
+
+ int32_t GetAppUnitsPerDevUnit() const {
+ return mAppUnitsPerDevUnit;
+ }
+
+ uint32_t GetLength() const {
+ return mLength;
+ }
+
+ bool FilterIfIgnorable(uint32_t aIndex, uint32_t aCh);
+
+protected:
+ // Allocate aCount DetailedGlyphs for the given index
+ DetailedGlyph *AllocateDetailedGlyphs(uint32_t aCharIndex,
+ uint32_t aCount);
+
+ // Ensure the glyph on the given index is complex glyph so that we can use
+ // it to record specific characters that layout may need to detect.
+ void EnsureComplexGlyph(uint32_t aIndex, CompressedGlyph& aGlyph)
+ {
+ MOZ_ASSERT(GetCharacterGlyphs() + aIndex == &aGlyph);
+ if (aGlyph.IsSimpleGlyph()) {
+ DetailedGlyph details = {
+ aGlyph.GetSimpleGlyph(),
+ (int32_t) aGlyph.GetSimpleAdvance(),
+ 0, 0
+ };
+ SetGlyphs(aIndex, CompressedGlyph().SetComplex(true, true, 1),
+ &details);
+ }
+ }
+
+ // For characters whose glyph data does not fit the "simple" glyph criteria
+ // in CompressedGlyph, we use a sorted array to store the association
+ // between the source character offset and an index into an array
+ // DetailedGlyphs. The CompressedGlyph record includes a count of
+ // the number of DetailedGlyph records that belong to the character,
+ // starting at the given index.
+ class DetailedGlyphStore {
+ public:
+ DetailedGlyphStore()
+ : mLastUsed(0)
+ { }
+
+ // This is optimized for the most common calling patterns:
+ // we rarely need random access to the records, access is most commonly
+ // sequential through the textRun, so we record the last-used index
+ // and check whether the caller wants the same record again, or the
+ // next; if not, it's most likely we're starting over from the start
+ // of the run, so we check the first entry before resorting to binary
+ // search as a last resort.
+ // NOTE that this must not be called for a character offset that does
+ // not have any DetailedGlyph records; callers must have verified that
+ // mCharacterGlyphs[aOffset].GetGlyphCount() is greater than zero
+ // before calling this, otherwise the assertions here will fire (in a
+ // debug build), and we'll probably crash.
+ DetailedGlyph* Get(uint32_t aOffset) {
+ NS_ASSERTION(mOffsetToIndex.Length() > 0,
+ "no detailed glyph records!");
+ DetailedGlyph* details = mDetails.Elements();
+ // check common cases (fwd iteration, initial entry, etc) first
+ if (mLastUsed < mOffsetToIndex.Length() - 1 &&
+ aOffset == mOffsetToIndex[mLastUsed + 1].mOffset) {
+ ++mLastUsed;
+ } else if (aOffset == mOffsetToIndex[0].mOffset) {
+ mLastUsed = 0;
+ } else if (aOffset == mOffsetToIndex[mLastUsed].mOffset) {
+ // do nothing
+ } else if (mLastUsed > 0 &&
+ aOffset == mOffsetToIndex[mLastUsed - 1].mOffset) {
+ --mLastUsed;
+ } else {
+ mLastUsed =
+ mOffsetToIndex.BinaryIndexOf(aOffset, CompareToOffset());
+ }
+ NS_ASSERTION(mLastUsed != nsTArray<DGRec>::NoIndex,
+ "detailed glyph record missing!");
+ return details + mOffsetToIndex[mLastUsed].mIndex;
+ }
+
+ DetailedGlyph* Allocate(uint32_t aOffset, uint32_t aCount) {
+ uint32_t detailIndex = mDetails.Length();
+ DetailedGlyph *details = mDetails.AppendElements(aCount);
+ // We normally set up glyph records sequentially, so the common case
+ // here is to append new records to the mOffsetToIndex array;
+ // test for that before falling back to the InsertElementSorted
+ // method.
+ if (mOffsetToIndex.Length() == 0 ||
+ aOffset > mOffsetToIndex[mOffsetToIndex.Length() - 1].mOffset) {
+ mOffsetToIndex.AppendElement(DGRec(aOffset, detailIndex));
+ } else {
+ mOffsetToIndex.InsertElementSorted(DGRec(aOffset, detailIndex),
+ CompareRecordOffsets());
+ }
+ return details;
+ }
+
+ size_t SizeOfIncludingThis(mozilla::MallocSizeOf aMallocSizeOf) {
+ return aMallocSizeOf(this) +
+ mDetails.ShallowSizeOfExcludingThis(aMallocSizeOf) +
+ mOffsetToIndex.ShallowSizeOfExcludingThis(aMallocSizeOf);
+ }
+
+ private:
+ struct DGRec {
+ DGRec(const uint32_t& aOffset, const uint32_t& aIndex)
+ : mOffset(aOffset), mIndex(aIndex) { }
+ uint32_t mOffset; // source character offset in the textrun
+ uint32_t mIndex; // index where this char's DetailedGlyphs begin
+ };
+
+ struct CompareToOffset {
+ bool Equals(const DGRec& a, const uint32_t& b) const {
+ return a.mOffset == b;
+ }
+ bool LessThan(const DGRec& a, const uint32_t& b) const {
+ return a.mOffset < b;
+ }
+ };
+
+ struct CompareRecordOffsets {
+ bool Equals(const DGRec& a, const DGRec& b) const {
+ return a.mOffset == b.mOffset;
+ }
+ bool LessThan(const DGRec& a, const DGRec& b) const {
+ return a.mOffset < b.mOffset;
+ }
+ };
+
+ // Concatenated array of all the DetailedGlyph records needed for the
+ // textRun; individual character offsets are associated with indexes
+ // into this array via the mOffsetToIndex table.
+ nsTArray<DetailedGlyph> mDetails;
+
+ // For each character offset that needs DetailedGlyphs, we record the
+ // index in mDetails where the list of glyphs begins. This array is
+ // sorted by mOffset.
+ nsTArray<DGRec> mOffsetToIndex;
+
+ // Records the most recently used index into mOffsetToIndex, so that
+ // we can support sequential access more quickly than just doing
+ // a binary search each time.
+ nsTArray<DGRec>::index_type mLastUsed;
+ };
+
+ mozilla::UniquePtr<DetailedGlyphStore> mDetailedGlyphs;
+
+ // Number of char16_t characters and CompressedGlyph glyph records
+ uint32_t mLength;
+
+ // Shaping flags (direction, ligature-suppression)
+ uint32_t mFlags;
+
+ int32_t mAppUnitsPerDevUnit;
+};
+
+/*
+ * gfxShapedWord: an individual (space-delimited) run of text shaped with a
+ * particular font, without regard to external context.
+ *
+ * The glyph data is copied into gfxTextRuns as needed from the cache of
+ * ShapedWords associated with each gfxFont instance.
+ */
+class gfxShapedWord final : public gfxShapedText
+{
+public:
+ typedef mozilla::unicode::Script Script;
+
+ // Create a ShapedWord that can hold glyphs for aLength characters,
+ // with mCharacterGlyphs sized appropriately.
+ //
+ // Returns null on allocation failure (does NOT use infallible alloc)
+ // so caller must check for success.
+ //
+ // This does NOT perform shaping, so the returned word contains no
+ // glyph data; the caller must call gfxFont::ShapeText() with appropriate
+ // parameters to set up the glyphs.
+ static gfxShapedWord* Create(const uint8_t *aText, uint32_t aLength,
+ Script aRunScript,
+ int32_t aAppUnitsPerDevUnit,
+ uint32_t aFlags) {
+ NS_ASSERTION(aLength <= gfxPlatform::GetPlatform()->WordCacheCharLimit(),
+ "excessive length for gfxShapedWord!");
+
+ // Compute size needed including the mCharacterGlyphs array
+ // and a copy of the original text
+ uint32_t size =
+ offsetof(gfxShapedWord, mCharGlyphsStorage) +
+ aLength * (sizeof(CompressedGlyph) + sizeof(uint8_t));
+ void *storage = malloc(size);
+ if (!storage) {
+ return nullptr;
+ }
+
+ // Construct in the pre-allocated storage, using placement new
+ return new (storage) gfxShapedWord(aText, aLength, aRunScript,
+ aAppUnitsPerDevUnit, aFlags);
+ }
+
+ static gfxShapedWord* Create(const char16_t *aText, uint32_t aLength,
+ Script aRunScript,
+ int32_t aAppUnitsPerDevUnit,
+ uint32_t aFlags) {
+ NS_ASSERTION(aLength <= gfxPlatform::GetPlatform()->WordCacheCharLimit(),
+ "excessive length for gfxShapedWord!");
+
+ // In the 16-bit version of Create, if the TEXT_IS_8BIT flag is set,
+ // then we convert the text to an 8-bit version and call the 8-bit
+ // Create function instead.
+ if (aFlags & gfxTextRunFactory::TEXT_IS_8BIT) {
+ nsAutoCString narrowText;
+ LossyAppendUTF16toASCII(nsDependentSubstring(aText, aLength),
+ narrowText);
+ return Create((const uint8_t*)(narrowText.BeginReading()),
+ aLength, aRunScript, aAppUnitsPerDevUnit, aFlags);
+ }
+
+ uint32_t size =
+ offsetof(gfxShapedWord, mCharGlyphsStorage) +
+ aLength * (sizeof(CompressedGlyph) + sizeof(char16_t));
+ void *storage = malloc(size);
+ if (!storage) {
+ return nullptr;
+ }
+
+ return new (storage) gfxShapedWord(aText, aLength, aRunScript,
+ aAppUnitsPerDevUnit, aFlags);
+ }
+
+ // Override operator delete to properly free the object that was
+ // allocated via malloc.
+ void operator delete(void* p) {
+ free(p);
+ }
+
+ virtual const CompressedGlyph *GetCharacterGlyphs() const override {
+ return &mCharGlyphsStorage[0];
+ }
+ virtual CompressedGlyph *GetCharacterGlyphs() override {
+ return &mCharGlyphsStorage[0];
+ }
+
+ const uint8_t* Text8Bit() const {
+ NS_ASSERTION(TextIs8Bit(), "invalid use of Text8Bit()");
+ return reinterpret_cast<const uint8_t*>(mCharGlyphsStorage + GetLength());
+ }
+
+ const char16_t* TextUnicode() const {
+ NS_ASSERTION(!TextIs8Bit(), "invalid use of TextUnicode()");
+ return reinterpret_cast<const char16_t*>(mCharGlyphsStorage + GetLength());
+ }
+
+ char16_t GetCharAt(uint32_t aOffset) const {
+ NS_ASSERTION(aOffset < GetLength(), "aOffset out of range");
+ return TextIs8Bit() ?
+ char16_t(Text8Bit()[aOffset]) : TextUnicode()[aOffset];
+ }
+
+ Script GetScript() const {
+ return mScript;
+ }
+
+ void ResetAge() {
+ mAgeCounter = 0;
+ }
+ uint32_t IncrementAge() {
+ return ++mAgeCounter;
+ }
+
+ // Helper used when hashing a word for the shaped-word caches
+ static uint32_t HashMix(uint32_t aHash, char16_t aCh)
+ {
+ return (aHash >> 28) ^ (aHash << 4) ^ aCh;
+ }
+
+private:
+ // so that gfxTextRun can share our DetailedGlyphStore class
+ friend class gfxTextRun;
+
+ // Construct storage for a ShapedWord, ready to receive glyph data
+ gfxShapedWord(const uint8_t *aText, uint32_t aLength,
+ Script aRunScript,
+ int32_t aAppUnitsPerDevUnit, uint32_t aFlags)
+ : gfxShapedText(aLength, aFlags | gfxTextRunFactory::TEXT_IS_8BIT,
+ aAppUnitsPerDevUnit)
+ , mScript(aRunScript)
+ , mAgeCounter(0)
+ {
+ memset(mCharGlyphsStorage, 0, aLength * sizeof(CompressedGlyph));
+ uint8_t *text = reinterpret_cast<uint8_t*>(&mCharGlyphsStorage[aLength]);
+ memcpy(text, aText, aLength * sizeof(uint8_t));
+ }
+
+ gfxShapedWord(const char16_t *aText, uint32_t aLength,
+ Script aRunScript,
+ int32_t aAppUnitsPerDevUnit, uint32_t aFlags)
+ : gfxShapedText(aLength, aFlags, aAppUnitsPerDevUnit)
+ , mScript(aRunScript)
+ , mAgeCounter(0)
+ {
+ memset(mCharGlyphsStorage, 0, aLength * sizeof(CompressedGlyph));
+ char16_t *text = reinterpret_cast<char16_t*>(&mCharGlyphsStorage[aLength]);
+ memcpy(text, aText, aLength * sizeof(char16_t));
+ SetupClusterBoundaries(0, aText, aLength);
+ }
+
+ Script mScript;
+
+ uint32_t mAgeCounter;
+
+ // The mCharGlyphsStorage array is actually a variable-size member;
+ // when the ShapedWord is created, its size will be increased as necessary
+ // to allow the proper number of glyphs to be stored.
+ // The original text, in either 8-bit or 16-bit form, will be stored
+ // immediately following the CompressedGlyphs.
+ CompressedGlyph mCharGlyphsStorage[1];
+};
+
+class GlyphBufferAzure;
+struct TextRunDrawParams;
+struct FontDrawParams;
+struct EmphasisMarkDrawParams;
+
+class gfxFont {
+
+ friend class gfxHarfBuzzShaper;
+ friend class gfxGraphiteShaper;
+
+protected:
+ typedef mozilla::gfx::DrawTarget DrawTarget;
+ typedef mozilla::unicode::Script Script;
+ typedef mozilla::SVGContextPaint SVGContextPaint;
+
+public:
+ nsrefcnt AddRef(void) {
+ NS_PRECONDITION(int32_t(mRefCnt) >= 0, "illegal refcnt");
+ if (mExpirationState.IsTracked()) {
+ gfxFontCache::GetCache()->RemoveObject(this);
+ }
+ ++mRefCnt;
+ NS_LOG_ADDREF(this, mRefCnt, "gfxFont", sizeof(*this));
+ return mRefCnt;
+ }
+ nsrefcnt Release(void) {
+ NS_PRECONDITION(0 != mRefCnt, "dup release");
+ --mRefCnt;
+ NS_LOG_RELEASE(this, mRefCnt, "gfxFont");
+ if (mRefCnt == 0) {
+ NotifyReleased();
+ // |this| may have been deleted.
+ return 0;
+ }
+ return mRefCnt;
+ }
+
+ int32_t GetRefCount() { return mRefCnt; }
+
+ // options to specify the kind of AA to be used when creating a font
+ typedef enum {
+ kAntialiasDefault,
+ kAntialiasNone,
+ kAntialiasGrayscale,
+ kAntialiasSubpixel
+ } AntialiasOption;
+
+protected:
+ nsAutoRefCnt mRefCnt;
+ cairo_scaled_font_t *mScaledFont;
+
+ void NotifyReleased() {
+ gfxFontCache *cache = gfxFontCache::GetCache();
+ if (cache) {
+ // Don't delete just yet; return the object to the cache for
+ // possibly recycling within some time limit
+ cache->NotifyReleased(this);
+ } else {
+ // The cache may have already been shut down.
+ delete this;
+ }
+ }
+
+ gfxFont(gfxFontEntry *aFontEntry, const gfxFontStyle *aFontStyle,
+ AntialiasOption anAAOption = kAntialiasDefault,
+ cairo_scaled_font_t *aScaledFont = nullptr);
+
+public:
+ virtual ~gfxFont();
+
+ bool Valid() const {
+ return mIsValid;
+ }
+
+ // options for the kind of bounding box to return from measurement
+ typedef enum {
+ LOOSE_INK_EXTENTS,
+ // A box that encloses all the painted pixels, and may
+ // include sidebearings and/or additional ascent/descent
+ // within the glyph cell even if the ink is smaller.
+ TIGHT_INK_EXTENTS,
+ // A box that tightly encloses all the painted pixels
+ // (although actually on Windows, at least, it may be
+ // slightly larger than strictly necessary because
+ // we can't get precise extents with ClearType).
+ TIGHT_HINTED_OUTLINE_EXTENTS
+ // A box that tightly encloses the glyph outline,
+ // ignoring possible antialiasing pixels that extend
+ // beyond this.
+ // NOTE: The default implementation of gfxFont::Measure(),
+ // which works with the glyph extents cache, does not
+ // differentiate between this and TIGHT_INK_EXTENTS.
+ // Whether the distinction is important depends on the
+ // antialiasing behavior of the platform; currently the
+ // distinction is only implemented in the gfxWindowsFont
+ // subclass, because of ClearType's tendency to paint
+ // outside the hinted outline.
+ // Also NOTE: it is relatively expensive to request this,
+ // as it does not use cached glyph extents in the font.
+ } BoundingBoxType;
+
+ const nsString& GetName() const { return mFontEntry->Name(); }
+ const gfxFontStyle *GetStyle() const { return &mStyle; }
+
+ virtual cairo_scaled_font_t* GetCairoScaledFont() { return mScaledFont; }
+
+ virtual gfxFont* CopyWithAntialiasOption(AntialiasOption anAAOption) {
+ // platforms where this actually matters should override
+ return nullptr;
+ }
+
+ gfxFloat GetAdjustedSize() const {
+ return mAdjustedSize > 0.0
+ ? mAdjustedSize
+ : (mStyle.sizeAdjust == 0.0 ? 0.0 : mStyle.size);
+ }
+
+ float FUnitsToDevUnitsFactor() const {
+ // check this was set up during font initialization
+ NS_ASSERTION(mFUnitsConvFactor >= 0.0f, "mFUnitsConvFactor not valid");
+ return mFUnitsConvFactor;
+ }
+
+ // check whether this is an sfnt we can potentially use with harfbuzz
+ bool FontCanSupportHarfBuzz() {
+ return mFontEntry->HasCmapTable();
+ }
+
+ // check whether this is an sfnt we can potentially use with Graphite
+ bool FontCanSupportGraphite() {
+ return mFontEntry->HasGraphiteTables();
+ }
+
+ // Whether this is a font that may be doing full-color rendering,
+ // and therefore needs us to use a mask for text-shadow even when
+ // we're not actually blurring.
+ bool AlwaysNeedsMaskForShadow() {
+ return mFontEntry->TryGetColorGlyphs() ||
+ mFontEntry->TryGetSVGData(this) ||
+ mFontEntry->HasFontTable(TRUETYPE_TAG('C','B','D','T')) ||
+ mFontEntry->HasFontTable(TRUETYPE_TAG('s','b','i','x'));
+ }
+
+ // whether a feature is supported by the font (limited to a small set
+ // of features for which some form of fallback needs to be implemented)
+ bool SupportsFeature(Script aScript, uint32_t aFeatureTag);
+
+ // whether the font supports "real" small caps, petite caps etc.
+ // aFallbackToSmallCaps true when petite caps should fallback to small caps
+ bool SupportsVariantCaps(Script aScript, uint32_t aVariantCaps,
+ bool& aFallbackToSmallCaps,
+ bool& aSyntheticLowerToSmallCaps,
+ bool& aSyntheticUpperToSmallCaps);
+
+ // whether the font supports subscript/superscript feature
+ // for fallback, need to verify that all characters in the run
+ // have variant substitutions
+ bool SupportsSubSuperscript(uint32_t aSubSuperscript,
+ const uint8_t *aString,
+ uint32_t aLength,
+ Script aRunScript);
+
+ bool SupportsSubSuperscript(uint32_t aSubSuperscript,
+ const char16_t *aString,
+ uint32_t aLength,
+ Script aRunScript);
+
+ // Subclasses may choose to look up glyph ids for characters.
+ // If they do not override this, gfxHarfBuzzShaper will fetch the cmap
+ // table and use that.
+ virtual bool ProvidesGetGlyph() const {
+ return false;
+ }
+ // Map unicode character to glyph ID.
+ // Only used if ProvidesGetGlyph() returns true.
+ virtual uint32_t GetGlyph(uint32_t unicode, uint32_t variation_selector) {
+ return 0;
+ }
+ // Return the horizontal advance of a glyph.
+ gfxFloat GetGlyphHAdvance(DrawTarget* aDrawTarget, uint16_t aGID);
+
+ // Return Azure GlyphRenderingOptions for drawing this font.
+ virtual already_AddRefed<mozilla::gfx::GlyphRenderingOptions>
+ GetGlyphRenderingOptions(const TextRunDrawParams* aRunParams = nullptr)
+ { return nullptr; }
+
+ gfxFloat SynthesizeSpaceWidth(uint32_t aCh);
+
+ // Font metrics
+ struct Metrics {
+ gfxFloat capHeight;
+ gfxFloat xHeight;
+ gfxFloat strikeoutSize;
+ gfxFloat strikeoutOffset;
+ gfxFloat underlineSize;
+ gfxFloat underlineOffset;
+
+ gfxFloat internalLeading;
+ gfxFloat externalLeading;
+
+ gfxFloat emHeight;
+ gfxFloat emAscent;
+ gfxFloat emDescent;
+ gfxFloat maxHeight;
+ gfxFloat maxAscent;
+ gfxFloat maxDescent;
+ gfxFloat maxAdvance;
+
+ gfxFloat aveCharWidth;
+ gfxFloat spaceWidth;
+ gfxFloat zeroOrAveCharWidth; // width of '0', or if there is
+ // no '0' glyph in this font,
+ // equal to .aveCharWidth
+ };
+
+ enum Orientation {
+ eHorizontal,
+ eVertical
+ };
+
+ const Metrics& GetMetrics(Orientation aOrientation)
+ {
+ if (aOrientation == eHorizontal) {
+ return GetHorizontalMetrics();
+ }
+ if (!mVerticalMetrics) {
+ mVerticalMetrics.reset(CreateVerticalMetrics());
+ }
+ return *mVerticalMetrics;
+ }
+
+ /**
+ * We let layout specify spacing on either side of any
+ * character. We need to specify both before and after
+ * spacing so that substring measurement can do the right things.
+ * These values are in appunits. They're always an integral number of
+ * appunits, but we specify them in floats in case very large spacing
+ * values are required.
+ */
+ struct Spacing {
+ gfxFloat mBefore;
+ gfxFloat mAfter;
+ };
+ /**
+ * Metrics for a particular string
+ */
+ struct RunMetrics {
+ RunMetrics() {
+ mAdvanceWidth = mAscent = mDescent = 0.0;
+ }
+
+ void CombineWith(const RunMetrics& aOther, bool aOtherIsOnLeft);
+
+ // can be negative (partly due to negative spacing).
+ // Advance widths should be additive: the advance width of the
+ // (offset1, length1) plus the advance width of (offset1 + length1,
+ // length2) should be the advance width of (offset1, length1 + length2)
+ gfxFloat mAdvanceWidth;
+
+ // For zero-width substrings, these must be zero!
+ gfxFloat mAscent; // always non-negative
+ gfxFloat mDescent; // always non-negative
+
+ // Bounding box that is guaranteed to include everything drawn.
+ // If a tight boundingBox was requested when these metrics were
+ // generated, this will tightly wrap the glyphs, otherwise it is
+ // "loose" and may be larger than the true bounding box.
+ // Coordinates are relative to the baseline left origin, so typically
+ // mBoundingBox.y == -mAscent
+ gfxRect mBoundingBox;
+ };
+
+ /**
+ * Draw a series of glyphs to aContext. The direction of aTextRun must
+ * be honoured.
+ * @param aStart the first character to draw
+ * @param aEnd draw characters up to here
+ * @param aPt the baseline origin; the left end of the baseline
+ * for LTR textruns, the right end for RTL textruns.
+ * On return, this will be updated to the other end of the baseline.
+ * In application units, really!
+ * @param aRunParams record with drawing parameters, see TextRunDrawParams.
+ * Particular fields of interest include
+ * .spacing spacing to insert before and after characters (for RTL
+ * glyphs, before-spacing is inserted to the right of characters). There
+ * are aEnd - aStart elements in this array, unless it's null to indicate
+ * that there is no spacing.
+ * .drawMode specifies whether the fill or stroke of the glyph should be
+ * drawn, or if it should be drawn into the current path
+ * .contextPaint information about how to construct the fill and
+ * stroke pattern. Can be nullptr if we are not stroking the text, which
+ * indicates that the current source from context should be used for fill
+ * .context the Thebes graphics context to which we're drawing
+ * .dt Moz2D DrawTarget to which we're drawing
+ *
+ * Callers guarantee:
+ * -- aStart and aEnd are aligned to cluster and ligature boundaries
+ * -- all glyphs use this font
+ */
+ void Draw(const gfxTextRun *aTextRun, uint32_t aStart, uint32_t aEnd,
+ gfxPoint *aPt, const TextRunDrawParams& aRunParams,
+ uint16_t aOrientation);
+
+ /**
+ * Draw the emphasis marks for the given text run. Its prerequisite
+ * and output are similiar to the method Draw().
+ * @param aPt the baseline origin of the emphasis marks.
+ * @param aParams some drawing parameters, see EmphasisMarkDrawParams.
+ */
+ void DrawEmphasisMarks(const gfxTextRun* aShapedText, gfxPoint* aPt,
+ uint32_t aOffset, uint32_t aCount,
+ const EmphasisMarkDrawParams& aParams);
+
+ /**
+ * Measure a run of characters. See gfxTextRun::Metrics.
+ * @param aTight if false, then return the union of the glyph extents
+ * with the font-box for the characters (the rectangle with x=0,width=
+ * the advance width for the character run,y=-(font ascent), and height=
+ * font ascent + font descent). Otherwise, we must return as tight as possible
+ * an approximation to the area actually painted by glyphs.
+ * @param aDrawTargetForTightBoundingBox when aTight is true, this must
+ * be non-null.
+ * @param aSpacing spacing to insert before and after glyphs. The bounding box
+ * need not include the spacing itself, but the spacing affects the glyph
+ * positions. null if there is no spacing.
+ *
+ * Callers guarantee:
+ * -- aStart and aEnd are aligned to cluster and ligature boundaries
+ * -- all glyphs use this font
+ *
+ * The default implementation just uses font metrics and aTextRun's
+ * advances, and assumes no characters fall outside the font box. In
+ * general this is insufficient, because that assumption is not always true.
+ */
+ virtual RunMetrics Measure(const gfxTextRun *aTextRun,
+ uint32_t aStart, uint32_t aEnd,
+ BoundingBoxType aBoundingBoxType,
+ DrawTarget* aDrawTargetForTightBoundingBox,
+ Spacing *aSpacing, uint16_t aOrientation);
+ /**
+ * Line breaks have been changed at the beginning and/or end of a substring
+ * of the text. Reshaping may be required; glyph updating is permitted.
+ * @return true if anything was changed, false otherwise
+ */
+ bool NotifyLineBreaksChanged(gfxTextRun *aTextRun,
+ uint32_t aStart, uint32_t aLength)
+ { return false; }
+
+ // Expiration tracking
+ nsExpirationState *GetExpirationState() { return &mExpirationState; }
+
+ // Get the glyphID of a space
+ virtual uint32_t GetSpaceGlyph() = 0;
+
+ gfxGlyphExtents *GetOrCreateGlyphExtents(int32_t aAppUnitsPerDevUnit);
+
+ // You need to call SetupCairoFont on aDrawTarget just before calling this.
+ virtual void SetupGlyphExtents(DrawTarget* aDrawTarget, uint32_t aGlyphID,
+ bool aNeedTight, gfxGlyphExtents *aExtents);
+
+ // This is called by the default Draw() implementation above.
+ virtual bool SetupCairoFont(DrawTarget* aDrawTarget) = 0;
+
+ virtual bool AllowSubpixelAA() { return true; }
+
+ bool IsSyntheticBold() { return mApplySyntheticBold; }
+
+ // Amount by which synthetic bold "fattens" the glyphs:
+ // For size S up to a threshold size T, we use (0.25 + 3S / 4T),
+ // so that the result ranges from 0.25 to 1.0; thereafter,
+ // simply use (S / T).
+ gfxFloat GetSyntheticBoldOffset() {
+ gfxFloat size = GetAdjustedSize();
+ const gfxFloat threshold = 48.0;
+ return size < threshold ? (0.25 + 0.75 * size / threshold) :
+ (size / threshold);
+ }
+
+ gfxFontEntry *GetFontEntry() const { return mFontEntry.get(); }
+ bool HasCharacter(uint32_t ch) {
+ if (!mIsValid ||
+ (mUnicodeRangeMap && !mUnicodeRangeMap->test(ch))) {
+ return false;
+ }
+ return mFontEntry->HasCharacter(ch);
+ }
+
+ const gfxCharacterMap* GetUnicodeRangeMap() const {
+ return mUnicodeRangeMap.get();
+ }
+
+ void SetUnicodeRangeMap(gfxCharacterMap* aUnicodeRangeMap) {
+ mUnicodeRangeMap = aUnicodeRangeMap;
+ }
+
+ uint16_t GetUVSGlyph(uint32_t aCh, uint32_t aVS) {
+ if (!mIsValid) {
+ return 0;
+ }
+ return mFontEntry->GetUVSGlyph(aCh, aVS);
+ }
+
+ template<typename T>
+ bool InitFakeSmallCapsRun(DrawTarget *aDrawTarget,
+ gfxTextRun *aTextRun,
+ const T *aText,
+ uint32_t aOffset,
+ uint32_t aLength,
+ uint8_t aMatchType,
+ uint16_t aOrientation,
+ Script aScript,
+ bool aSyntheticLower,
+ bool aSyntheticUpper);
+
+ // call the (virtual) InitTextRun method to do glyph generation/shaping,
+ // limiting the length of text passed by processing the run in multiple
+ // segments if necessary
+ template<typename T>
+ bool SplitAndInitTextRun(DrawTarget *aDrawTarget,
+ gfxTextRun *aTextRun,
+ const T *aString,
+ uint32_t aRunStart,
+ uint32_t aRunLength,
+ Script aRunScript,
+ bool aVertical);
+
+ // Get a ShapedWord representing the given text (either 8- or 16-bit)
+ // for use in setting up a gfxTextRun.
+ template<typename T>
+ gfxShapedWord* GetShapedWord(DrawTarget *aDrawTarget,
+ const T *aText,
+ uint32_t aLength,
+ uint32_t aHash,
+ Script aRunScript,
+ bool aVertical,
+ int32_t aAppUnitsPerDevUnit,
+ uint32_t aFlags,
+ gfxTextPerfMetrics *aTextPerf);
+
+ // Ensure the ShapedWord cache is initialized. This MUST be called before
+ // any attempt to use GetShapedWord().
+ void InitWordCache() {
+ if (!mWordCache) {
+ mWordCache = mozilla::MakeUnique<nsTHashtable<CacheHashEntry>>();
+ }
+ }
+
+ // Called by the gfxFontCache timer to increment the age of all the words,
+ // so that they'll expire after a sufficient period of non-use
+ void AgeCachedWords();
+
+ // Discard all cached word records; called on memory-pressure notification.
+ void ClearCachedWords() {
+ if (mWordCache) {
+ mWordCache->Clear();
+ }
+ }
+
+ // Glyph rendering/geometry has changed, so invalidate data as necessary.
+ void NotifyGlyphsChanged();
+
+ virtual void AddSizeOfExcludingThis(mozilla::MallocSizeOf aMallocSizeOf,
+ FontCacheSizes* aSizes) const;
+ virtual void AddSizeOfIncludingThis(mozilla::MallocSizeOf aMallocSizeOf,
+ FontCacheSizes* aSizes) const;
+
+ typedef enum {
+ FONT_TYPE_DWRITE,
+ FONT_TYPE_GDI,
+ FONT_TYPE_FT2,
+ FONT_TYPE_MAC,
+ FONT_TYPE_OS2,
+ FONT_TYPE_CAIRO,
+ FONT_TYPE_FONTCONFIG
+ } FontType;
+
+ virtual FontType GetType() const = 0;
+
+ virtual already_AddRefed<mozilla::gfx::ScaledFont> GetScaledFont(DrawTarget* aTarget)
+ { return gfxPlatform::GetPlatform()->GetScaledFontForFont(aTarget, this); }
+
+ bool KerningDisabled() {
+ return mKerningSet && !mKerningEnabled;
+ }
+
+ /**
+ * Subclass this object to be notified of glyph changes. Delete the object
+ * when no longer needed.
+ */
+ class GlyphChangeObserver {
+ public:
+ virtual ~GlyphChangeObserver()
+ {
+ if (mFont) {
+ mFont->RemoveGlyphChangeObserver(this);
+ }
+ }
+ // This gets called when the gfxFont dies.
+ void ForgetFont() { mFont = nullptr; }
+ virtual void NotifyGlyphsChanged() = 0;
+ protected:
+ explicit GlyphChangeObserver(gfxFont *aFont) : mFont(aFont)
+ {
+ mFont->AddGlyphChangeObserver(this);
+ }
+ // This pointer is nulled by ForgetFont in the gfxFont's
+ // destructor. Before the gfxFont dies.
+ gfxFont* MOZ_NON_OWNING_REF mFont;
+ };
+ friend class GlyphChangeObserver;
+
+ bool GlyphsMayChange()
+ {
+ // Currently only fonts with SVG glyphs can have animated glyphs
+ return mFontEntry->TryGetSVGData(this);
+ }
+
+ static void DestroySingletons() {
+ delete sScriptTagToCode;
+ delete sDefaultFeatures;
+ }
+
+ // Call TryGetMathTable() to try and load the Open Type MATH table.
+ // If (and ONLY if) TryGetMathTable() has returned true, the MathTable()
+ // method may be called to access the gfxMathTable data.
+ bool TryGetMathTable();
+ gfxMathTable* MathTable() {
+ MOZ_RELEASE_ASSERT(mMathTable, "A successful call to TryGetMathTable() must be performed before calling this function");
+ return mMathTable.get();
+ }
+
+ // return a cloned font resized and offset to simulate sub/superscript glyphs
+ virtual already_AddRefed<gfxFont>
+ GetSubSuperscriptFont(int32_t aAppUnitsPerDevPixel);
+
+ /**
+ * Return the reference cairo_t object from aDT.
+ */
+ static cairo_t* RefCairo(mozilla::gfx::DrawTarget* aDT);
+
+protected:
+ virtual const Metrics& GetHorizontalMetrics() = 0;
+
+ const Metrics* CreateVerticalMetrics();
+
+ // Output a single glyph at *aPt, which is updated by the glyph's advance.
+ // Normal glyphs are simply accumulated in aBuffer until it is full and
+ // gets flushed, but SVG or color-font glyphs will instead be rendered
+ // directly to the destination (found from the buffer's parameters).
+ void DrawOneGlyph(uint32_t aGlyphID,
+ double aAdvance,
+ gfxPoint *aPt,
+ GlyphBufferAzure& aBuffer,
+ bool *aEmittedGlyphs) const;
+
+ // Output a run of glyphs at *aPt, which is updated to follow the last glyph
+ // in the run. This method also takes account of any letter-spacing provided
+ // in aRunParams.
+ bool DrawGlyphs(const gfxShapedText *aShapedText,
+ uint32_t aOffset, // offset in the textrun
+ uint32_t aCount, // length of run to draw
+ gfxPoint *aPt,
+ const TextRunDrawParams& aRunParams,
+ const FontDrawParams& aFontParams);
+
+ // set the font size and offset used for
+ // synthetic subscript/superscript glyphs
+ void CalculateSubSuperSizeAndOffset(int32_t aAppUnitsPerDevPixel,
+ gfxFloat& aSubSuperSizeRatio,
+ float& aBaselineOffset);
+
+ // Return a font that is a "clone" of this one, but reduced to 80% size
+ // (and with variantCaps set to normal).
+ // Default implementation relies on gfxFontEntry::CreateFontInstance;
+ // backends that don't implement that will need to override this and use
+ // an alternative technique. (gfxFontconfigFonts, I'm looking at you...)
+ virtual already_AddRefed<gfxFont> GetSmallCapsFont();
+
+ // subclasses may provide (possibly hinted) glyph widths (in font units);
+ // if they do not override this, harfbuzz will use unhinted widths
+ // derived from the font tables
+ virtual bool ProvidesGlyphWidths() const {
+ return false;
+ }
+
+ // The return value is interpreted as a horizontal advance in 16.16 fixed
+ // point format.
+ virtual int32_t GetGlyphWidth(DrawTarget& aDrawTarget, uint16_t aGID) {
+ return -1;
+ }
+
+ bool IsSpaceGlyphInvisible(DrawTarget* aRefDrawTarget,
+ const gfxTextRun* aTextRun);
+
+ void AddGlyphChangeObserver(GlyphChangeObserver *aObserver);
+ void RemoveGlyphChangeObserver(GlyphChangeObserver *aObserver);
+
+ // whether font contains substitution lookups containing spaces
+ bool HasSubstitutionRulesWithSpaceLookups(Script aRunScript);
+
+ // do spaces participate in shaping rules? if so, can't used word cache
+ bool SpaceMayParticipateInShaping(Script aRunScript);
+
+ // For 8-bit text, expand to 16-bit and then call the following method.
+ bool ShapeText(DrawTarget *aContext,
+ const uint8_t *aText,
+ uint32_t aOffset, // dest offset in gfxShapedText
+ uint32_t aLength,
+ Script aScript,
+ bool aVertical,
+ gfxShapedText *aShapedText); // where to store the result
+
+ // Call the appropriate shaper to generate glyphs for aText and store
+ // them into aShapedText.
+ virtual bool ShapeText(DrawTarget *aContext,
+ const char16_t *aText,
+ uint32_t aOffset,
+ uint32_t aLength,
+ Script aScript,
+ bool aVertical,
+ gfxShapedText *aShapedText);
+
+ // Helper to adjust for synthetic bold and set character-type flags
+ // in the shaped text; implementations of ShapeText should call this
+ // after glyph shaping has been completed.
+ void PostShapingFixup(DrawTarget* aContext,
+ const char16_t* aText,
+ uint32_t aOffset, // position within aShapedText
+ uint32_t aLength,
+ bool aVertical,
+ gfxShapedText* aShapedText);
+
+ // Shape text directly into a range within a textrun, without using the
+ // font's word cache. Intended for use when the font has layout features
+ // that involve space, and therefore require shaping complete runs rather
+ // than isolated words, or for long strings that are inefficient to cache.
+ // This will split the text on "invalid" characters (tab/newline) that are
+ // not handled via normal shaping, but does not otherwise divide up the
+ // text.
+ template<typename T>
+ bool ShapeTextWithoutWordCache(DrawTarget *aDrawTarget,
+ const T *aText,
+ uint32_t aOffset,
+ uint32_t aLength,
+ Script aScript,
+ bool aVertical,
+ gfxTextRun *aTextRun);
+
+ // Shape a fragment of text (a run that is known to contain only
+ // "valid" characters, no newlines/tabs/other control chars).
+ // All non-wordcache shaping goes through here; this is the function
+ // that will ensure we don't pass excessively long runs to the various
+ // platform shapers.
+ template<typename T>
+ bool ShapeFragmentWithoutWordCache(DrawTarget *aDrawTarget,
+ const T *aText,
+ uint32_t aOffset,
+ uint32_t aLength,
+ Script aScript,
+ bool aVertical,
+ gfxTextRun *aTextRun);
+
+ void CheckForFeaturesInvolvingSpace();
+
+ // whether a given feature is included in feature settings from both the
+ // font and the style. aFeatureOn set if resolved feature value is non-zero
+ bool HasFeatureSet(uint32_t aFeature, bool& aFeatureOn);
+
+ // used when analyzing whether a font has space contextual lookups
+ static nsDataHashtable<nsUint32HashKey,Script> *sScriptTagToCode;
+ static nsTHashtable<nsUint32HashKey> *sDefaultFeatures;
+
+ RefPtr<gfxFontEntry> mFontEntry;
+
+ struct CacheHashKey {
+ union {
+ const uint8_t *mSingle;
+ const char16_t *mDouble;
+ } mText;
+ uint32_t mLength;
+ uint32_t mFlags;
+ Script mScript;
+ int32_t mAppUnitsPerDevUnit;
+ PLDHashNumber mHashKey;
+ bool mTextIs8Bit;
+
+ CacheHashKey(const uint8_t *aText, uint32_t aLength,
+ uint32_t aStringHash,
+ Script aScriptCode, int32_t aAppUnitsPerDevUnit,
+ uint32_t aFlags)
+ : mLength(aLength),
+ mFlags(aFlags),
+ mScript(aScriptCode),
+ mAppUnitsPerDevUnit(aAppUnitsPerDevUnit),
+ mHashKey(aStringHash + static_cast<int32_t>(aScriptCode) +
+ aAppUnitsPerDevUnit * 0x100 + aFlags * 0x10000),
+ mTextIs8Bit(true)
+ {
+ NS_ASSERTION(aFlags & gfxTextRunFactory::TEXT_IS_8BIT,
+ "8-bit flag should have been set");
+ mText.mSingle = aText;
+ }
+
+ CacheHashKey(const char16_t *aText, uint32_t aLength,
+ uint32_t aStringHash,
+ Script aScriptCode, int32_t aAppUnitsPerDevUnit,
+ uint32_t aFlags)
+ : mLength(aLength),
+ mFlags(aFlags),
+ mScript(aScriptCode),
+ mAppUnitsPerDevUnit(aAppUnitsPerDevUnit),
+ mHashKey(aStringHash + static_cast<int32_t>(aScriptCode) +
+ aAppUnitsPerDevUnit * 0x100 + aFlags * 0x10000),
+ mTextIs8Bit(false)
+ {
+ // We can NOT assert that TEXT_IS_8BIT is false in aFlags here,
+ // because this might be an 8bit-only word from a 16-bit textrun,
+ // in which case the text we're passed is still in 16-bit form,
+ // and we'll have to use an 8-to-16bit comparison in KeyEquals.
+ mText.mDouble = aText;
+ }
+ };
+
+ class CacheHashEntry : public PLDHashEntryHdr {
+ public:
+ typedef const CacheHashKey &KeyType;
+ typedef const CacheHashKey *KeyTypePointer;
+
+ // When constructing a new entry in the hashtable, the caller of Put()
+ // will fill us in.
+ explicit CacheHashEntry(KeyTypePointer aKey) { }
+ CacheHashEntry(const CacheHashEntry& toCopy) { NS_ERROR("Should not be called"); }
+ ~CacheHashEntry() { }
+
+ bool KeyEquals(const KeyTypePointer aKey) const;
+
+ static KeyTypePointer KeyToPointer(KeyType aKey) { return &aKey; }
+
+ static PLDHashNumber HashKey(const KeyTypePointer aKey) {
+ return aKey->mHashKey;
+ }
+
+ size_t SizeOfExcludingThis(mozilla::MallocSizeOf aMallocSizeOf) const
+ {
+ return aMallocSizeOf(mShapedWord.get());
+ }
+
+ enum { ALLOW_MEMMOVE = true };
+
+ mozilla::UniquePtr<gfxShapedWord> mShapedWord;
+ };
+
+ mozilla::UniquePtr<nsTHashtable<CacheHashEntry> > mWordCache;
+
+ static const uint32_t kShapedWordCacheMaxAge = 3;
+
+ bool mIsValid;
+
+ // use synthetic bolding for environments where this is not supported
+ // by the platform
+ bool mApplySyntheticBold;
+
+ bool mKerningSet; // kerning explicitly set?
+ bool mKerningEnabled; // if set, on or off?
+
+ bool mMathInitialized; // TryGetMathTable() called?
+
+ nsExpirationState mExpirationState;
+ gfxFontStyle mStyle;
+ nsTArray<mozilla::UniquePtr<gfxGlyphExtents>> mGlyphExtentsArray;
+ mozilla::UniquePtr<nsTHashtable<nsPtrHashKey<GlyphChangeObserver>>>
+ mGlyphChangeObservers;
+
+ gfxFloat mAdjustedSize;
+
+ // Conversion factor from font units to dev units; note that this may be
+ // zero (in the degenerate case where mAdjustedSize has become zero).
+ // This is OK because we only multiply by this factor, never divide.
+ float mFUnitsConvFactor;
+
+ // the AA setting requested for this font - may affect glyph bounds
+ AntialiasOption mAntialiasOption;
+
+ // a copy of the font without antialiasing, if needed for separate
+ // measurement by mathml code
+ mozilla::UniquePtr<gfxFont> mNonAAFont;
+
+ // we create either or both of these shapers when needed, depending
+ // whether the font has graphite tables, and whether graphite shaping
+ // is actually enabled
+ mozilla::UniquePtr<gfxFontShaper> mHarfBuzzShaper;
+ mozilla::UniquePtr<gfxFontShaper> mGraphiteShaper;
+
+ // if a userfont with unicode-range specified, contains map of *possible*
+ // ranges supported by font
+ RefPtr<gfxCharacterMap> mUnicodeRangeMap;
+
+ RefPtr<mozilla::gfx::ScaledFont> mAzureScaledFont;
+
+ // For vertical metrics, created on demand.
+ mozilla::UniquePtr<const Metrics> mVerticalMetrics;
+
+ // Table used for MathML layout.
+ mozilla::UniquePtr<gfxMathTable> mMathTable;
+
+ // Helper for subclasses that want to initialize standard metrics from the
+ // tables of sfnt (TrueType/OpenType) fonts.
+ // This will use mFUnitsConvFactor if it is already set, else compute it
+ // from mAdjustedSize and the unitsPerEm in the font's 'head' table.
+ // Returns TRUE and sets mIsValid=TRUE if successful;
+ // Returns TRUE but leaves mIsValid=FALSE if the font seems to be broken.
+ // Returns FALSE if the font does not appear to be an sfnt at all,
+ // and should be handled (if possible) using other APIs.
+ bool InitMetricsFromSfntTables(Metrics& aMetrics);
+
+ // Helper to calculate various derived metrics from the results of
+ // InitMetricsFromSfntTables or equivalent platform code
+ void CalculateDerivedMetrics(Metrics& aMetrics);
+
+ // some fonts have bad metrics, this method sanitize them.
+ // if this font has bad underline offset, aIsBadUnderlineFont should be true.
+ void SanitizeMetrics(Metrics *aMetrics, bool aIsBadUnderlineFont);
+
+ bool RenderSVGGlyph(gfxContext *aContext, gfxPoint aPoint,
+ uint32_t aGlyphId, SVGContextPaint* aContextPaint) const;
+ bool RenderSVGGlyph(gfxContext *aContext, gfxPoint aPoint,
+ uint32_t aGlyphId, SVGContextPaint* aContextPaint,
+ gfxTextRunDrawCallbacks *aCallbacks,
+ bool& aEmittedGlyphs) const;
+
+ bool RenderColorGlyph(DrawTarget* aDrawTarget,
+ gfxContext* aContext,
+ mozilla::gfx::ScaledFont* scaledFont,
+ mozilla::gfx::GlyphRenderingOptions* renderingOptions,
+ mozilla::gfx::DrawOptions drawOptions,
+ const mozilla::gfx::Point& aPoint,
+ uint32_t aGlyphId) const;
+
+ // Bug 674909. When synthetic bolding text by drawing twice, need to
+ // render using a pixel offset in device pixels, otherwise text
+ // doesn't appear bolded, it appears as if a bad text shadow exists
+ // when a non-identity transform exists. Use an offset factor so that
+ // the second draw occurs at a constant offset in device pixels.
+ // This helper calculates the scale factor we need to apply to the
+ // synthetic-bold offset.
+ static double CalcXScale(DrawTarget* aDrawTarget);
+};
+
+// proportion of ascent used for x-height, if unable to read value from font
+#define DEFAULT_XHEIGHT_FACTOR 0.56f
+
+// Parameters passed to gfxFont methods for drawing glyphs from a textrun.
+// The TextRunDrawParams are set up once per textrun; the FontDrawParams
+// are dependent on the specific font, so they are set per GlyphRun.
+
+struct TextRunDrawParams {
+ RefPtr<mozilla::gfx::DrawTarget> dt;
+ gfxContext *context;
+ gfxFont::Spacing *spacing;
+ gfxTextRunDrawCallbacks *callbacks;
+ mozilla::SVGContextPaint *runContextPaint;
+ mozilla::gfx::Color fontSmoothingBGColor;
+ gfxFloat direction;
+ double devPerApp;
+ nscolor textStrokeColor;
+ gfxPattern *textStrokePattern;
+ const mozilla::gfx::StrokeOptions *strokeOpts;
+ const mozilla::gfx::DrawOptions *drawOpts;
+ DrawMode drawMode;
+ bool isVerticalRun;
+ bool isRTL;
+ bool paintSVGGlyphs;
+};
+
+struct FontDrawParams {
+ RefPtr<mozilla::gfx::ScaledFont> scaledFont;
+ RefPtr<mozilla::gfx::GlyphRenderingOptions> renderingOptions;
+ mozilla::SVGContextPaint *contextPaint;
+ mozilla::gfx::Matrix *passedInvMatrix;
+ mozilla::gfx::Matrix matInv;
+ double synBoldOnePixelOffset;
+ int32_t extraStrikes;
+ mozilla::gfx::DrawOptions drawOptions;
+ bool isVerticalFont;
+ bool haveSVGGlyphs;
+ bool haveColorGlyphs;
+};
+
+struct EmphasisMarkDrawParams {
+ gfxContext* context;
+ gfxFont::Spacing* spacing;
+ gfxTextRun* mark;
+ gfxFloat advance;
+ gfxFloat direction;
+ bool isVertical;
+};
+
+#endif
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-24 12:29:06 +0000