--- a/graphicsdeviceinterface/gdi/sgdi/BidiCopy.cpp Wed Aug 25 08:17:25 2010 +0300
+++ /dev/null Thu Jan 01 00:00:00 1970 +0000
@@ -1,341 +0,0 @@
-// Copyright (c) 2002-2009 Nokia Corporation and/or its subsidiary(-ies).
-// All rights reserved.
-// This component and the accompanying materials are made available
-// under the terms of "Eclipse Public License v1.0"
-// which accompanies this distribution, and is available
-// at the URL "http://www.eclipse.org/legal/epl-v10.html".
-//
-// Initial Contributors:
-// Nokia Corporation - initial contribution.
-//
-// Contributors:
-//
-// Description:
-//
-
-#include "BidiCopy.h"
-#include <e32std.h>
-#include "mglyphs.inl"
-
-TInt BidiCopy::Mirror(TInt a)
-/**
-Find the mirror image of a character.
-@internalComponent
-*/
- {
- TInt current = MirrorStart(a);
- unsigned long v = mGlyphArray[current];
- TInt key = v >> 16;
- // 1st easy-out: no steps at all for any at this key
- if (key == 0)
- return a;
- // 2nd easy-out: no steps at all but we have found it
- if (key == a)
- return v & 0xFFFF;
- TInt step = MirrorStep(a);
- do {
- current += step;
- current &= (KMirrorTableSize-1);
- key = mGlyphArray[current] >> 16;
- if (key == a)
- return mGlyphArray[current] & 0xFFFF;
- } while (key != 0);
- return a;
- }
-
-void BidiCopy::ReverseCodes(TText* aText, TInt aLength)
-/**
-Reverse the contents of aText[0..aLength], so that aText[0] holds the
-value previously found in aText[aLength - 1], aText[1] holds the value
-previously held in aText[aLength - 2] and so on.
-@internalComponent
-*/
- {
- TText *text = aText; // backup
-
- // reverse int16 by int16 (note: high surrogate + low surrogate will be reverse to low surrogate + high surrogate)
- TText* end = aText + aLength - 1;
- while (aText < end)
- {
- TText t = *aText;
- *aText = *end;
- *end = t;
- ++aText;
- --end;
- }
-
- CorrectSurrogatePairs(text, aLength);
- }
-
-void BidiCopy::DeleteUnreversedSurrogates(TText* aText, TInt aLength)
-/**
-Replaces all surrogates with 0xFFFF that are not paired up the wrong
-way round.
-@internalComponent
-*/
- {
- if (aLength < 1)
- return;
- TText* end = aText + aLength;
- while (aText < end)
- {
- if ((aText[0] & 0xF800) == 0xD800)
- {
- if ((aText[0] & 0xFC00) == 0xD800
- && aText + 1 != end
- && (aText[1] & 0xFC00) == 0xDC00)
- ++aText;
- else
- aText[0] = 0xFFFF;
- }
- ++aText;
- }
- }
-
-void BidiCopy::CorrectSurrogatePairs(TText* aText, TInt aLength)
-/**
-Corrects all reversed surrogate pairs. Assumes that no unpaired
-surrogates are present.
-@internalComponent
-*/
- {
- TText* end = aText + aLength;
- while (aText < end)
- {
- if ((aText[0] & 0xF800) == 0xD800)
- {
- // Surrogate pair discovered.
- // Do we need to swap it?
- ASSERT(aText + 1 < end);
- ASSERT((aText[1] & 0xF800) == 0xD800);
- if ((aText[0] & 0xFC00) == 0xDC00)
- {
- ASSERT((aText[1] & 0xFC00) == 0xD800);
- TText t = aText[0];
- aText[0] = aText[1];
- aText[1] = t;
- }
- ++aText;
- }
- ++aText;
- }
- }
-
-void BidiCopy::CorrectGroups(TText* aText, TInt aLength)
-/**
-Correct all reversed groups (non-combiner followed by combining
-characters). Surrogate pairs may be reversed by this operation.
-Assumes that no unpaired surrogates are present.
-Leading and trailing 0xFFFFs are left alone.
-@internalComponent
-*/
- {
- TText *end = aText + aLength;
- // Ignore leading 0xFFFFs. This helps Tagma's
- // RTmTextCache::GetDisplayedText with its sentinels.
- while (aText < end && *aText == 0xFFFF)
- ++aText;
- TText* groupStart = aText;
- while (aText < end)
- {
- TText* next = aText + 1;
- TInt c = aText[0];
- if ((c & 0xFC00) == 0xD800)
- {
- ASSERT(aText + 1 < end);
- ASSERT((aText[1] & 0xFC00) == 0xDC00);
- c = (c << 10) + (aText[1] & 0x3FF)
- + (0x10000 - 0xD800*0x400);
- ++next;
- }
- // ignore non-characters
- if ((c & 0xFFFE) != 0xFFFE)
- {
- // non-marks represent the end of groups that may need to
- // be reversed
- TChar ch = c;
- if ((ch.GetCategory() & 0xFFFFFFF0) != TChar::EMarkGroup)
- {
- if (aText != groupStart)
- ReverseCodes(groupStart, aText - groupStart + 1);
- groupStart = next;
- }
- }
- aText = next;
- }
- }
-
-void BidiCopy::SubstituteMirrorImages(TText* aText, TInt aLength)
-/**
-Reverse all mirror image characters. Will not change characters
-in the basic multilingual plane for surrogate pairs. Assumes
-that no unpaired surrogates are present.
-@internalComponent
-*/
- {
- TText *end = aText + aLength;
- while (aText < end)
- {
- TText* next = aText + 1;
- TInt c = aText[0];
- if ((c & 0xFC00) == 0xD800)
- {
- ASSERT(aText + 1 < end);
- ASSERT((aText[1] & 0xFC00) == 0xDC00);
- c = (c << 10) + (aText[1] & 0x3FF)
- + (0x10000 - 0xD800*0x400);
- ++next;
- }
- TInt m = Mirror(c);
- if (m != c)
- {
- if (m <= 0xFFFF)
- {
- aText[0] = static_cast<TText>(m);
- if (0xFFFF < c)
- aText[1] = 0xFFFF;
- }
- else if (0xFFFF < c)
- {
- aText[0] = static_cast<TText>((c >> 10) + 0xD760);
- aText[1] = static_cast<TText>((c & 0x3FF) + 0xDC00);
- }
- }
- aText = next;
- }
- }
-
-TText* BidiCopy::CopyMirror(TText* aDestination, const TText* aSource, TInt length)
-/**
-Copy some text, substituting mirrored characters.
-
-@return aDestination + number of TText codes output.
-@internalComponent
-*/
- {
- for (; length; --length, ++aDestination, ++aSource)
- *aDestination = static_cast<TText>(Mirror(*aSource));
- return aDestination;
- }
-
-TText* BidiCopy::OutputTChar(TText* aDestination, TInt aToOutput)
-/**
-Write out the input character as UTF16.
-
-@return aDestination + number of TText codes output.
-@internalComponent
-*/
- {
- if (aToOutput > 0xFFFF)
- {
- TInt c = aToOutput;
- aDestination[0] = static_cast<TText>((c >> 10) + 0xD760);
- aDestination[1] = static_cast<TText>((c & 0x3FF) + 0xDC00);
- return aDestination + 2;
- }
- *aDestination = static_cast<TText>(aToOutput);
- return aDestination + 1;
- }
-
-TText* BidiCopy::CopyBackwards(TText* aDestination,
- const TText* aSource, TInt aLength)
-/**
-Copy the text backwards without substituting mirrored characters,
-checking for surrogate pairs or combining characters.
-
-@return aDestination + number of TText codes output.
-@internalComponent
-*/
- {
- TText *end = aDestination + aLength;
- while (aDestination != end)
- {
- *--end = *aSource++;
- }
- return aDestination + aLength;
- }
-
-TText* BidiCopy::CopyBackwardsWithMirroring(TText* aDestination,
- const TText* aSource, TInt aLength)
-/**
-Copy the text backwards to the output without checking for surrogate
-pairs or combining characters, substituting mirrored characters.
-
-@return aDestination + number of TText codes output.
-@internalComponent
-*/
- {
- TText *end = aDestination + aLength;
- while (aDestination != end)
- {
- *--end = static_cast<TText>(Mirror(*aSource++));
- }
- return aDestination + aLength;
- }
-
-TText* BidiCopy::CopyGroupsBackwards(TText* aDestination,
- const TText* aSource, TInt aLength)
-/**
-Copy the text backwards, substituting mirrored characters and correctly
-handling all surrogate pairs and combining characters.
-
-@return aDestination + number of TText codes output.
-@internalComponent
-*/
- {
- TText* retval = CopyBackwards(aDestination, aSource, aLength);
- DeleteUnreversedSurrogates(aDestination, aLength);
- SubstituteMirrorImages(aDestination, aLength);
- CorrectGroups(aDestination, aLength);
- CorrectSurrogatePairs(aDestination, aLength);
- return retval;
- }
-
-TBool BidiCopy::ImplicitDirectionalityIsRightToLeft(
- const TText* aText, TInt aLength, TBool* aFound)
-/**
-Find out if the implicit directionality of a piece of text is right to
-left.
-
-@param aText Text to be examined, or the first portion of text to be examined.
-@param aLength Length of the text.
-@param aFound If non-null, returns ETrue if the directionality could be
-determined from aText. If not, and there is more text beyond, the function
-should be called with the next portion of text until aFound returns ETrue
-or there is no more text.
-@return ETrue if the directionality is right to left. If the directionality
-cannot be determined solely from this text, EFalse is returned. This is the
-implicit directionality of text that is composed entirely of neutrals.
-@internalComponent
-*/
- {
- if (aFound)
- *aFound = ETrue;
- const TText* end = aText + aLength;
- TInt lastUtf16 = 0;
- while (aText != end)
- {
- TInt code = *aText++;
- if ((code & 0xFFFFFC00) == 0xD800
- && (lastUtf16 & 0xFFFFFC00) == 0xDC00)
- {
- code = (code << 10) + (lastUtf16 & 0x3FF)
- + (0x10000 - 0xD800*0x400);
- }
- lastUtf16 = code;
- TChar c = code;
- switch(c.GetBdCategory())
- {
- case TChar::ELeftToRight:
- return EFalse;
- case TChar::ERightToLeft:
- case TChar::ERightToLeftArabic:
- return ETrue;
- default:
- break;
- }
- }
- if (aFound)
- *aFound = EFalse;
- return EFalse;
- }