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Diffstat (limited to 'layout/generic/nsTextRunTransformations.h')
| -rw-r--r-- | layout/generic/nsTextRunTransformations.h | 222 |
1 files changed, 222 insertions, 0 deletions
diff --git a/layout/generic/nsTextRunTransformations.h b/layout/generic/nsTextRunTransformations.h new file mode 100644 index 000000000..662a5d2f8 --- /dev/null +++ b/layout/generic/nsTextRunTransformations.h @@ -0,0 +1,222 @@ +/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- + * 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 NSTEXTRUNTRANSFORMATIONS_H_ +#define NSTEXTRUNTRANSFORMATIONS_H_ + +#include "mozilla/Attributes.h" +#include "mozilla/MemoryReporting.h" +#include "mozilla/UniquePtr.h" +#include "gfxTextRun.h" +#include "nsStyleContext.h" + +class nsTransformedTextRun; + +struct nsTransformedCharStyle final { + NS_INLINE_DECL_REFCOUNTING(nsTransformedCharStyle) + + explicit nsTransformedCharStyle(nsStyleContext* aContext) + : mFont(aContext->StyleFont()->mFont) + , mLanguage(aContext->StyleFont()->mLanguage) + , mPresContext(aContext->PresContext()) + , mScriptSizeMultiplier(aContext->StyleFont()->mScriptSizeMultiplier) + , mTextTransform(aContext->StyleText()->mTextTransform) + , mMathVariant(aContext->StyleFont()->mMathVariant) + , mExplicitLanguage(aContext->StyleFont()->mExplicitLanguage) {} + + nsFont mFont; + nsCOMPtr<nsIAtom> mLanguage; + RefPtr<nsPresContext> mPresContext; + float mScriptSizeMultiplier; + uint8_t mTextTransform; + uint8_t mMathVariant; + bool mExplicitLanguage; + bool mForceNonFullWidth = false; + +private: + ~nsTransformedCharStyle() {} + nsTransformedCharStyle(const nsTransformedCharStyle& aOther) = delete; + nsTransformedCharStyle& operator=(const nsTransformedCharStyle& aOther) = delete; +}; + +class nsTransformingTextRunFactory { +public: + virtual ~nsTransformingTextRunFactory() {} + + // Default 8-bit path just transforms to Unicode and takes that path + already_AddRefed<nsTransformedTextRun> + MakeTextRun(const uint8_t* aString, uint32_t aLength, + const gfxFontGroup::Parameters* aParams, + gfxFontGroup* aFontGroup, uint32_t aFlags, + nsTArray<RefPtr<nsTransformedCharStyle>>&& aStyles, + bool aOwnsFactory); + + already_AddRefed<nsTransformedTextRun> + MakeTextRun(const char16_t* aString, uint32_t aLength, + const gfxFontGroup::Parameters* aParams, + gfxFontGroup* aFontGroup, uint32_t aFlags, + nsTArray<RefPtr<nsTransformedCharStyle>>&& aStyles, + bool aOwnsFactory); + + virtual void RebuildTextRun(nsTransformedTextRun* aTextRun, + mozilla::gfx::DrawTarget* aRefDrawTarget, + gfxMissingFontRecorder* aMFR) = 0; +}; + +/** + * Builds textruns that transform the text in some way (e.g., capitalize) + * and then render the text using some other textrun implementation. + */ +class nsCaseTransformTextRunFactory : public nsTransformingTextRunFactory { +public: + // We could add an optimization here so that when there is no inner + // factory, no title-case conversion, and no upper-casing of SZLIG, we override + // MakeTextRun (after making it virtual in the superclass) and have it + // just convert the string to uppercase or lowercase and create the textrun + // via the fontgroup. + + // Takes ownership of aInnerTransformTextRunFactory + explicit nsCaseTransformTextRunFactory(UniquePtr<nsTransformingTextRunFactory> aInnerTransformingTextRunFactory, + bool aAllUppercase = false) + : mInnerTransformingTextRunFactory(Move(aInnerTransformingTextRunFactory)), + mAllUppercase(aAllUppercase) {} + + virtual void RebuildTextRun(nsTransformedTextRun* aTextRun, + mozilla::gfx::DrawTarget* aRefDrawTarget, + gfxMissingFontRecorder* aMFR) override; + + // Perform a transformation on the given string, writing the result into + // aConvertedString. If aAllUppercase is true, the transform is (global) + // upper-casing, and aLanguage is used to determine any language-specific + // behavior; otherwise, an nsTransformedTextRun should be passed in + // as aTextRun and its styles will be used to determine the transform(s) + // to be applied. + // If such an input textrun is provided, then its line-breaks and styles + // will be copied to the output arrays, which must also be provided by + // the caller. For the global upper-casing usage (no input textrun), + // these are ignored. + static bool TransformString(const nsAString& aString, + nsString& aConvertedString, + bool aAllUppercase, + const nsIAtom* aLanguage, + nsTArray<bool>& aCharsToMergeArray, + nsTArray<bool>& aDeletedCharsArray, + const nsTransformedTextRun* aTextRun = nullptr, + uint32_t aOffsetInTextRun = 0, + nsTArray<uint8_t>* aCanBreakBeforeArray = nullptr, + nsTArray<RefPtr<nsTransformedCharStyle>>* aStyleArray = nullptr); + +protected: + mozilla::UniquePtr<nsTransformingTextRunFactory> mInnerTransformingTextRunFactory; + bool mAllUppercase; +}; + +/** + * So that we can reshape as necessary, we store enough information + * to fully rebuild the textrun contents. + */ +class nsTransformedTextRun final : public gfxTextRun { +public: + + static already_AddRefed<nsTransformedTextRun> + Create(const gfxTextRunFactory::Parameters* aParams, + nsTransformingTextRunFactory* aFactory, + gfxFontGroup* aFontGroup, + const char16_t* aString, uint32_t aLength, + const uint32_t aFlags, + nsTArray<RefPtr<nsTransformedCharStyle>>&& aStyles, + bool aOwnsFactory); + + ~nsTransformedTextRun() { + if (mOwnsFactory) { + delete mFactory; + } + } + + void SetCapitalization(uint32_t aStart, uint32_t aLength, + bool* aCapitalization); + virtual bool SetPotentialLineBreaks(Range aRange, + const uint8_t* aBreakBefore); + /** + * Called after SetCapitalization and SetPotentialLineBreaks + * are done and before we request any data from the textrun. Also always + * called after a Create. + */ + void FinishSettingProperties(mozilla::gfx::DrawTarget* aRefDrawTarget, + gfxMissingFontRecorder* aMFR) + { + if (mNeedsRebuild) { + mNeedsRebuild = false; + mFactory->RebuildTextRun(this, aRefDrawTarget, aMFR); + } + } + + // override the gfxTextRun impls to account for additional members here + virtual size_t SizeOfExcludingThis(mozilla::MallocSizeOf aMallocSizeOf) MOZ_MUST_OVERRIDE; + virtual size_t SizeOfIncludingThis(mozilla::MallocSizeOf aMallocSizeOf) MOZ_MUST_OVERRIDE; + + nsTransformingTextRunFactory *mFactory; + nsTArray<RefPtr<nsTransformedCharStyle>> mStyles; + nsTArray<bool> mCapitalize; + nsString mString; + bool mOwnsFactory; + bool mNeedsRebuild; + +private: + nsTransformedTextRun(const gfxTextRunFactory::Parameters* aParams, + nsTransformingTextRunFactory* aFactory, + gfxFontGroup* aFontGroup, + const char16_t* aString, uint32_t aLength, + const uint32_t aFlags, + nsTArray<RefPtr<nsTransformedCharStyle>>&& aStyles, + bool aOwnsFactory) + : gfxTextRun(aParams, aLength, aFontGroup, aFlags), + mFactory(aFactory), mStyles(aStyles), mString(aString, aLength), + mOwnsFactory(aOwnsFactory), mNeedsRebuild(true) + { + mCharacterGlyphs = reinterpret_cast<CompressedGlyph*>(this + 1); + } +}; + +/** + * Copy a given textrun, but merge certain characters into a single logical + * character. Glyphs for a character are added to the glyph list for the previous + * character and then the merged character is eliminated. Visually the results + * are identical. + * + * This is used for text-transform:uppercase when we encounter a SZLIG, + * whose uppercase form is "SS", or other ligature or precomposed form + * that expands to multiple codepoints during case transformation, + * and for Greek text when combining diacritics have been deleted. + * + * This function is unable to merge characters when they occur in different + * glyph runs. This only happens in tricky edge cases where a character was + * decomposed by case-mapping (e.g. there's no precomposed uppercase version + * of an accented lowercase letter), and then font-matching caused the + * diacritics to be assigned to a different font than the base character. + * In this situation, the diacritic(s) get discarded, which is less than + * ideal, but they probably weren't going to render very well anyway. + * Bug 543200 will improve this by making font-matching operate on entire + * clusters instead of individual codepoints. + * + * For simplicity, this produces a textrun containing all DetailedGlyphs, + * no simple glyphs. So don't call it unless you really have merging to do. + * + * @param aCharsToMerge when aCharsToMerge[i] is true, this character in aSrc + * is merged into the previous character + * + * @param aDeletedChars when aDeletedChars[i] is true, the character at this + * position in aDest was deleted (has no corresponding char in aSrc) + */ +void +MergeCharactersInTextRun(gfxTextRun* aDest, gfxTextRun* aSrc, + const bool* aCharsToMerge, const bool* aDeletedChars); + +gfxTextRunFactory::Parameters +GetParametersForInner(nsTransformedTextRun* aTextRun, uint32_t* aFlags, + mozilla::gfx::DrawTarget* aRefDrawTarget); + + +#endif /*NSTEXTRUNTRANSFORMATIONS_H_*/ |