/* -*- 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 NSTEXTFRAMEUTILS_H_ #define NSTEXTFRAMEUTILS_H_ #include "gfxSkipChars.h" #include "nsBidiUtils.h" #include "nsUnicodeProperties.h" class nsIContent; struct nsStyleText; #define BIG_TEXT_NODE_SIZE 4096 #define CH_NBSP 160 #define CH_SHY 173 #define CH_CJKSP 12288 // U+3000 IDEOGRAPHIC SPACE (CJK Full-Width Space) class nsTextFrameUtils { public: // These constants are used as textrun flags for textframe textruns. enum { // The following flags are set by TransformText // the text has at least one untransformed tab character TEXT_HAS_TAB = 0x010000, // the original text has at least one soft hyphen character TEXT_HAS_SHY = 0x020000, TEXT_WAS_TRANSFORMED = 0x040000, TEXT_UNUSED_FLAG = 0x080000, // The following flags are set by nsTextFrame TEXT_IS_SIMPLE_FLOW = 0x100000, TEXT_INCOMING_WHITESPACE = 0x200000, TEXT_TRAILING_WHITESPACE = 0x400000, TEXT_COMPRESSED_LEADING_WHITESPACE = 0x800000, TEXT_NO_BREAKS = 0x1000000, TEXT_IS_TRANSFORMED = 0x2000000, // This gets set if there's a break opportunity at the end of the textrun. // We normally don't use this break opportunity because the following text // will have a break opportunity at the start, but it's useful for line // layout to know about it in case the following content is not text TEXT_HAS_TRAILING_BREAK = 0x4000000, // This is set if the textrun was created for a textframe whose // NS_FRAME_IS_IN_SINGLE_CHAR_MI flag is set. This occurs if the textframe // belongs to a MathML <mi> element whose embedded text consists of a // single character. TEXT_IS_SINGLE_CHAR_MI = 0x8000000, // This is set if the text run might be observing for glyph changes. TEXT_MIGHT_HAVE_GLYPH_CHANGES = 0x10000000, // The following are defined by gfxTextRunWordCache rather than here, // so that it also has access to the _INCOMING flag // TEXT_TRAILING_ARABICCHAR // TEXT_INCOMING_ARABICCHAR // This is defined in gfxTextRunFactory to allow access in gfxFont. // TEXT_USE_MATH_SCRIPT }; // These constants are used in TransformText to represent context information // from previous textruns. enum { INCOMING_NONE = 0, INCOMING_WHITESPACE = 1, INCOMING_ARABICCHAR = 2 }; /** * Returns true if aChars/aLength are something that make a space * character not be whitespace when they follow the space character * (combining mark or join control, ignoring intervening direction * controls). */ static bool IsSpaceCombiningSequenceTail(const char16_t* aChars, int32_t aLength) { return aLength > 0 && (mozilla::unicode::IsClusterExtender(aChars[0]) || (IsBidiControl(aChars[0]) && IsSpaceCombiningSequenceTail(aChars + 1, aLength - 1) ) ); } enum CompressionMode { COMPRESS_NONE, COMPRESS_WHITESPACE, COMPRESS_WHITESPACE_NEWLINE, COMPRESS_NONE_TRANSFORM_TO_SPACE }; /** * Create a text run from a run of Unicode text. The text may have whitespace * compressed. A preformatted tab is sent to the text run as a single space. * (Tab spacing must be performed by textframe later.) Certain other * characters are discarded. * * @param aCompressWhitespace control what is compressed to a * single space character: no compression, compress spaces (not followed * by combining mark) and tabs, compress those plus newlines, or * no compression except newlines are discarded. * @param aIncomingFlags a flag indicating whether there was whitespace * or an Arabic character preceding this text. We set it to indicate if * there's an Arabic character or whitespace preceding the end of this text. */ static char16_t* TransformText(const char16_t* aText, uint32_t aLength, char16_t* aOutput, CompressionMode aCompression, uint8_t * aIncomingFlags, gfxSkipChars* aSkipChars, uint32_t* aAnalysisFlags); static uint8_t* TransformText(const uint8_t* aText, uint32_t aLength, uint8_t* aOutput, CompressionMode aCompression, uint8_t * aIncomingFlags, gfxSkipChars* aSkipChars, uint32_t* aAnalysisFlags); static void AppendLineBreakOffset(nsTArray<uint32_t>* aArray, uint32_t aOffset) { if (aArray->Length() > 0 && (*aArray)[aArray->Length() - 1] == aOffset) return; aArray->AppendElement(aOffset); } static uint32_t ComputeApproximateLengthWithWhitespaceCompression(nsIContent *aContent, const nsStyleText *aStyleText); }; class nsSkipCharsRunIterator { public: enum LengthMode { LENGTH_UNSKIPPED_ONLY = false, LENGTH_INCLUDES_SKIPPED = true }; nsSkipCharsRunIterator(const gfxSkipCharsIterator& aStart, LengthMode aLengthIncludesSkipped, uint32_t aLength) : mIterator(aStart), mRemainingLength(aLength), mRunLength(0), mVisitSkipped(false), mLengthIncludesSkipped(aLengthIncludesSkipped) { } void SetVisitSkipped() { mVisitSkipped = true; } void SetOriginalOffset(int32_t aOffset) { mIterator.SetOriginalOffset(aOffset); } void SetSkippedOffset(uint32_t aOffset) { mIterator.SetSkippedOffset(aOffset); } // guaranteed to return only positive-length runs bool NextRun(); bool IsSkipped() const { return mSkipped; } // Always returns something > 0 int32_t GetRunLength() const { return mRunLength; } const gfxSkipCharsIterator& GetPos() const { return mIterator; } int32_t GetOriginalOffset() const { return mIterator.GetOriginalOffset(); } uint32_t GetSkippedOffset() const { return mIterator.GetSkippedOffset(); } private: gfxSkipCharsIterator mIterator; int32_t mRemainingLength; int32_t mRunLength; bool mSkipped; bool mVisitSkipped; bool mLengthIncludesSkipped; }; #endif /*NSTEXTFRAMEUTILS_H_*/