1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/layout/generic/nsTextRunTransformations.h Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,175 @@
1.4 +/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
1.5 + * This Source Code Form is subject to the terms of the Mozilla Public
1.6 + * License, v. 2.0. If a copy of the MPL was not distributed with this
1.7 + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
1.8 +
1.9 +#ifndef NSTEXTRUNTRANSFORMATIONS_H_
1.10 +#define NSTEXTRUNTRANSFORMATIONS_H_
1.11 +
1.12 +#include "mozilla/Attributes.h"
1.13 +#include "mozilla/MemoryReporting.h"
1.14 +#include "gfxFont.h"
1.15 +
1.16 +class nsTransformedTextRun;
1.17 +class nsStyleContext;
1.18 +
1.19 +class nsTransformingTextRunFactory {
1.20 +public:
1.21 + virtual ~nsTransformingTextRunFactory() {}
1.22 +
1.23 + // Default 8-bit path just transforms to Unicode and takes that path
1.24 + nsTransformedTextRun* MakeTextRun(const uint8_t* aString, uint32_t aLength,
1.25 + const gfxFontGroup::Parameters* aParams,
1.26 + gfxFontGroup* aFontGroup, uint32_t aFlags,
1.27 + nsStyleContext** aStyles, bool aOwnsFactory = true);
1.28 + nsTransformedTextRun* MakeTextRun(const char16_t* aString, uint32_t aLength,
1.29 + const gfxFontGroup::Parameters* aParams,
1.30 + gfxFontGroup* aFontGroup, uint32_t aFlags,
1.31 + nsStyleContext** aStyles, bool aOwnsFactory = true);
1.32 +
1.33 + virtual void RebuildTextRun(nsTransformedTextRun* aTextRun, gfxContext* aRefContext) = 0;
1.34 +};
1.35 +
1.36 +/**
1.37 + * Builds textruns that render their text using a font-variant (i.e.,
1.38 + * smallcaps).
1.39 + */
1.40 +class nsFontVariantTextRunFactory : public nsTransformingTextRunFactory {
1.41 +public:
1.42 + virtual void RebuildTextRun(nsTransformedTextRun* aTextRun, gfxContext* aRefContext) MOZ_OVERRIDE;
1.43 +};
1.44 +
1.45 +/**
1.46 + * Builds textruns that transform the text in some way (e.g., capitalize)
1.47 + * and then render the text using some other textrun implementation.
1.48 + */
1.49 +class nsCaseTransformTextRunFactory : public nsTransformingTextRunFactory {
1.50 +public:
1.51 + // We could add an optimization here so that when there is no inner
1.52 + // factory, no title-case conversion, and no upper-casing of SZLIG, we override
1.53 + // MakeTextRun (after making it virtual in the superclass) and have it
1.54 + // just convert the string to uppercase or lowercase and create the textrun
1.55 + // via the fontgroup.
1.56 +
1.57 + // Takes ownership of aInnerTransformTextRunFactory
1.58 + nsCaseTransformTextRunFactory(nsTransformingTextRunFactory* aInnerTransformingTextRunFactory,
1.59 + bool aAllUppercase = false)
1.60 + : mInnerTransformingTextRunFactory(aInnerTransformingTextRunFactory),
1.61 + mAllUppercase(aAllUppercase) {}
1.62 +
1.63 + virtual void RebuildTextRun(nsTransformedTextRun* aTextRun, gfxContext* aRefContext) MOZ_OVERRIDE;
1.64 +
1.65 +protected:
1.66 + nsAutoPtr<nsTransformingTextRunFactory> mInnerTransformingTextRunFactory;
1.67 + bool mAllUppercase;
1.68 +};
1.69 +
1.70 +/**
1.71 + * So that we can reshape as necessary, we store enough information
1.72 + * to fully rebuild the textrun contents.
1.73 + */
1.74 +class nsTransformedTextRun : public gfxTextRun {
1.75 +public:
1.76 + static nsTransformedTextRun *Create(const gfxTextRunFactory::Parameters* aParams,
1.77 + nsTransformingTextRunFactory* aFactory,
1.78 + gfxFontGroup* aFontGroup,
1.79 + const char16_t* aString, uint32_t aLength,
1.80 + const uint32_t aFlags, nsStyleContext** aStyles,
1.81 + bool aOwnsFactory);
1.82 +
1.83 + ~nsTransformedTextRun() {
1.84 + if (mOwnsFactory) {
1.85 + delete mFactory;
1.86 + }
1.87 + }
1.88 +
1.89 + void SetCapitalization(uint32_t aStart, uint32_t aLength,
1.90 + bool* aCapitalization,
1.91 + gfxContext* aRefContext);
1.92 + virtual bool SetPotentialLineBreaks(uint32_t aStart, uint32_t aLength,
1.93 + uint8_t* aBreakBefore,
1.94 + gfxContext* aRefContext);
1.95 + /**
1.96 + * Called after SetCapitalization and SetPotentialLineBreaks
1.97 + * are done and before we request any data from the textrun. Also always
1.98 + * called after a Create.
1.99 + */
1.100 + void FinishSettingProperties(gfxContext* aRefContext)
1.101 + {
1.102 + if (mNeedsRebuild) {
1.103 + mNeedsRebuild = false;
1.104 + mFactory->RebuildTextRun(this, aRefContext);
1.105 + }
1.106 + }
1.107 +
1.108 + // override the gfxTextRun impls to account for additional members here
1.109 + virtual size_t SizeOfExcludingThis(mozilla::MallocSizeOf aMallocSizeOf) MOZ_MUST_OVERRIDE;
1.110 + virtual size_t SizeOfIncludingThis(mozilla::MallocSizeOf aMallocSizeOf) MOZ_MUST_OVERRIDE;
1.111 +
1.112 + nsTransformingTextRunFactory *mFactory;
1.113 + nsTArray<nsRefPtr<nsStyleContext> > mStyles;
1.114 + nsTArray<bool> mCapitalize;
1.115 + nsString mString;
1.116 + bool mOwnsFactory;
1.117 + bool mNeedsRebuild;
1.118 +
1.119 +private:
1.120 + nsTransformedTextRun(const gfxTextRunFactory::Parameters* aParams,
1.121 + nsTransformingTextRunFactory* aFactory,
1.122 + gfxFontGroup* aFontGroup,
1.123 + const char16_t* aString, uint32_t aLength,
1.124 + const uint32_t aFlags, nsStyleContext** aStyles,
1.125 + bool aOwnsFactory)
1.126 + : gfxTextRun(aParams, aLength, aFontGroup, aFlags),
1.127 + mFactory(aFactory), mString(aString, aLength),
1.128 + mOwnsFactory(aOwnsFactory), mNeedsRebuild(true)
1.129 + {
1.130 + mCharacterGlyphs = reinterpret_cast<CompressedGlyph*>(this + 1);
1.131 +
1.132 + uint32_t i;
1.133 + for (i = 0; i < aLength; ++i) {
1.134 + mStyles.AppendElement(aStyles[i]);
1.135 + }
1.136 + }
1.137 +};
1.138 +
1.139 +/**
1.140 + * Copy a given textrun, but merge certain characters into a single logical
1.141 + * character. Glyphs for a character are added to the glyph list for the previous
1.142 + * character and then the merged character is eliminated. Visually the results
1.143 + * are identical.
1.144 + *
1.145 + * This is used for text-transform:uppercase when we encounter a SZLIG,
1.146 + * whose uppercase form is "SS", or other ligature or precomposed form
1.147 + * that expands to multiple codepoints during case transformation,
1.148 + * and for Greek text when combining diacritics have been deleted.
1.149 + *
1.150 + * This function is unable to merge characters when they occur in different
1.151 + * glyph runs. This only happens in tricky edge cases where a character was
1.152 + * decomposed by case-mapping (e.g. there's no precomposed uppercase version
1.153 + * of an accented lowercase letter), and then font-matching caused the
1.154 + * diacritics to be assigned to a different font than the base character.
1.155 + * In this situation, the diacritic(s) get discarded, which is less than
1.156 + * ideal, but they probably weren't going to render very well anyway.
1.157 + * Bug 543200 will improve this by making font-matching operate on entire
1.158 + * clusters instead of individual codepoints.
1.159 + *
1.160 + * For simplicity, this produces a textrun containing all DetailedGlyphs,
1.161 + * no simple glyphs. So don't call it unless you really have merging to do.
1.162 + *
1.163 + * @param aCharsToMerge when aCharsToMerge[i] is true, this character in aSrc
1.164 + * is merged into the previous character
1.165 + *
1.166 + * @param aDeletedChars when aDeletedChars[i] is true, the character at this
1.167 + * position in aDest was deleted (has no corresponding char in aSrc)
1.168 + */
1.169 +void
1.170 +MergeCharactersInTextRun(gfxTextRun* aDest, gfxTextRun* aSrc,
1.171 + const bool* aCharsToMerge, const bool* aDeletedChars);
1.172 +
1.173 +gfxTextRunFactory::Parameters
1.174 +GetParametersForInner(nsTransformedTextRun* aTextRun, uint32_t* aFlags,
1.175 + gfxContext* aRefContext);
1.176 +
1.177 +
1.178 +#endif /*NSTEXTRUNTRANSFORMATIONS_H_*/
