| /* |
| ****************************************************************************** |
| * |
| * Copyright (C) 1999-2005, International Business Machines |
| * Corporation and others. All Rights Reserved. |
| * |
| ****************************************************************************** |
| * file name: ubidi.h |
| * encoding: US-ASCII |
| * tab size: 8 (not used) |
| * indentation:4 |
| * |
| * created on: 1999jul27 |
| * created by: Markus W. Scherer |
| */ |
| |
| #ifndef UBIDI_H |
| #define UBIDI_H |
| |
| #include "unicode/utypes.h" |
| #include "unicode/uchar.h" |
| |
| /* |
| * javadoc-style comments are intended to be transformed into HTML |
| * using DOC++ - see |
| * http://www.zib.de/Visual/software/doc++/index.html . |
| * |
| * The HTML documentation is created with |
| * doc++ -H ubidi.h |
| * |
| * The following #define trick allows us to do it all in one file |
| * and still be able to compile it. |
| */ |
| /*#define DOCXX_TAG*/ |
| /*#define BIDI_SAMPLE_CODE*/ |
| |
| /** |
| *\file |
| * \brief C API: BIDI algorithm |
| * |
| * <h2>BIDI algorithm for ICU</h2> |
| * |
| * This is an implementation of the Unicode Bidirectional algorithm. |
| * The algorithm is defined in the |
| * <a href="http://www.unicode.org/unicode/reports/tr9/">Unicode Standard Annex #9</a>, |
| * version 13, also described in The Unicode Standard, Version 4.0 .<p> |
| * |
| * Note: Libraries that perform a bidirectional algorithm and |
| * reorder strings accordingly are sometimes called "Storage Layout Engines". |
| * ICU's BiDi and shaping (u_shapeArabic()) APIs can be used at the core of such |
| * "Storage Layout Engines". |
| * |
| * <h3>General remarks about the API:</h3> |
| * |
| * In functions with an error code parameter, |
| * the <code>pErrorCode</code> pointer must be valid |
| * and the value that it points to must not indicate a failure before |
| * the function call. Otherwise, the function returns immediately. |
| * After the function call, the value indicates success or failure.<p> |
| * |
| * The "limit" of a sequence of characters is the position just after their |
| * last character, i.e., one more than that position.<p> |
| * |
| * Some of the API functions provide access to "runs". |
| * Such a "run" is defined as a sequence of characters |
| * that are at the same embedding level |
| * after performing the BIDI algorithm.<p> |
| * |
| * @author Markus W. Scherer |
| * @version 1.0 |
| * |
| * |
| * <h4> Sample code for the ICU BIDI API </h4> |
| * |
| * <h5>Rendering a paragraph with the ICU BiDi API</h5> |
| * |
| * This is (hypothetical) sample code that illustrates |
| * how the ICU BiDi API could be used to render a paragraph of text. |
| * Rendering code depends highly on the graphics system, |
| * therefore this sample code must make a lot of assumptions, |
| * which may or may not match any existing graphics system's properties. |
| * |
| * <p>The basic assumptions are:</p> |
| * <ul> |
| * <li>Rendering is done from left to right on a horizontal line.</li> |
| * <li>A run of single-style, unidirectional text can be rendered at once.</li> |
| * <li>Such a run of text is passed to the graphics system with |
| * characters (code units) in logical order.</li> |
| * <li>The line-breaking algorithm is very complicated |
| * and Locale-dependent - |
| * and therefore its implementation omitted from this sample code.</li> |
| * </ul> |
| * |
| * <pre> |
| * \code |
| *#include "unicode/ubidi.h" |
| * |
| *typedef enum { |
| * styleNormal=0, styleSelected=1, |
| * styleBold=2, styleItalics=4, |
| * styleSuper=8, styleSub=16 |
| *} Style; |
| * |
| *typedef struct { int32_t limit; Style style; } StyleRun; |
| * |
| *int getTextWidth(const UChar *text, int32_t start, int32_t limit, |
| * const StyleRun *styleRuns, int styleRunCount); |
| * |
| * // set *pLimit and *pStyleRunLimit for a line |
| * // from text[start] and from styleRuns[styleRunStart] |
| * // using ubidi_getLogicalRun(para, ...) |
| *void getLineBreak(const UChar *text, int32_t start, int32_t *pLimit, |
| * UBiDi *para, |
| * const StyleRun *styleRuns, int styleRunStart, int *pStyleRunLimit, |
| * int *pLineWidth); |
| * |
| * // render runs on a line sequentially, always from left to right |
| * |
| * // prepare rendering a new line |
| * void startLine(UBiDiDirection textDirection, int lineWidth); |
| * |
| * // render a run of text and advance to the right by the run width |
| * // the text[start..limit-1] is always in logical order |
| * void renderRun(const UChar *text, int32_t start, int32_t limit, |
| * UBiDiDirection textDirection, Style style); |
| * |
| * // We could compute a cross-product |
| * // from the style runs with the directional runs |
| * // and then reorder it. |
| * // Instead, here we iterate over each run type |
| * // and render the intersections - |
| * // with shortcuts in simple (and common) cases. |
| * // renderParagraph() is the main function. |
| * |
| * // render a directional run with |
| * // (possibly) multiple style runs intersecting with it |
| * void renderDirectionalRun(const UChar *text, |
| * int32_t start, int32_t limit, |
| * UBiDiDirection direction, |
| * const StyleRun *styleRuns, int styleRunCount) { |
| * int i; |
| * |
| * // iterate over style runs |
| * if(direction==UBIDI_LTR) { |
| * int styleLimit; |
| * |
| * for(i=0; i<styleRunCount; ++i) { |
| * styleLimit=styleRun[i].limit; |
| * if(start<styleLimit) { |
| * if(styleLimit>limit) { styleLimit=limit; } |
| * renderRun(text, start, styleLimit, |
| * direction, styleRun[i].style); |
| * if(styleLimit==limit) { break; } |
| * start=styleLimit; |
| * } |
| * } |
| * } else { |
| * int styleStart; |
| * |
| * for(i=styleRunCount-1; i>=0; --i) { |
| * if(i>0) { |
| * styleStart=styleRun[i-1].limit; |
| * } else { |
| * styleStart=0; |
| * } |
| * if(limit>=styleStart) { |
| * if(styleStart<start) { styleStart=start; } |
| * renderRun(text, styleStart, limit, |
| * direction, styleRun[i].style); |
| * if(styleStart==start) { break; } |
| * limit=styleStart; |
| * } |
| * } |
| * } |
| * } |
| * |
| * // the line object represents text[start..limit-1] |
| * void renderLine(UBiDi *line, const UChar *text, |
| * int32_t start, int32_t limit, |
| * const StyleRun *styleRuns, int styleRunCount) { |
| * UBiDiDirection direction=ubidi_getDirection(line); |
| * if(direction!=UBIDI_MIXED) { |
| * // unidirectional |
| * if(styleRunCount<=1) { |
| * renderRun(text, start, limit, direction, styleRuns[0].style); |
| * } else { |
| * renderDirectionalRun(text, start, limit, |
| * direction, styleRuns, styleRunCount); |
| * } |
| * } else { |
| * // mixed-directional |
| * int32_t count, i, length; |
| * UBiDiLevel level; |
| * |
| * count=ubidi_countRuns(para, pErrorCode); |
| * if(U_SUCCESS(*pErrorCode)) { |
| * if(styleRunCount<=1) { |
| * Style style=styleRuns[0].style; |
| * |
| * // iterate over directional runs |
| * for(i=0; i<count; ++i) { |
| * direction=ubidi_getVisualRun(para, i, &start, &length); |
| * renderRun(text, start, start+length, direction, style); |
| * } |
| * } else { |
| * int32_t j; |
| * |
| * // iterate over both directional and style runs |
| * for(i=0; i<count; ++i) { |
| * direction=ubidi_getVisualRun(line, i, &start, &length); |
| * renderDirectionalRun(text, start, start+length, |
| * direction, styleRuns, styleRunCount); |
| * } |
| * } |
| * } |
| * } |
| * } |
| * |
| *void renderParagraph(const UChar *text, int32_t length, |
| * UBiDiDirection textDirection, |
| * const StyleRun *styleRuns, int styleRunCount, |
| * int lineWidth, |
| * UErrorCode *pErrorCode) { |
| * UBiDi *para; |
| * |
| * if(pErrorCode==NULL || U_FAILURE(*pErrorCode) || length<=0) { |
| * return; |
| * } |
| * |
| * para=ubidi_openSized(length, 0, pErrorCode); |
| * if(para==NULL) { return; } |
| * |
| * ubidi_setPara(para, text, length, |
| * textDirection ? UBIDI_DEFAULT_RTL : UBIDI_DEFAULT_LTR, |
| * NULL, pErrorCode); |
| * if(U_SUCCESS(*pErrorCode)) { |
| * UBiDiLevel paraLevel=1&ubidi_getParaLevel(para); |
| * StyleRun styleRun={ length, styleNormal }; |
| * int width; |
| * |
| * if(styleRuns==NULL || styleRunCount<=0) { |
| * styleRunCount=1; |
| * styleRuns=&styleRun; |
| * } |
| * |
| * // assume styleRuns[styleRunCount-1].limit>=length |
| * |
| * width=getTextWidth(text, 0, length, styleRuns, styleRunCount); |
| * if(width<=lineWidth) { |
| * // everything fits onto one line |
| * |
| * // prepare rendering a new line from either left or right |
| * startLine(paraLevel, width); |
| * |
| * renderLine(para, text, 0, length, |
| * styleRuns, styleRunCount); |
| * } else { |
| * UBiDi *line; |
| * |
| * // we need to render several lines |
| * line=ubidi_openSized(length, 0, pErrorCode); |
| * if(line!=NULL) { |
| * int32_t start=0, limit; |
| * int styleRunStart=0, styleRunLimit; |
| * |
| * for(;;) { |
| * limit=length; |
| * styleRunLimit=styleRunCount; |
| * getLineBreak(text, start, &limit, para, |
| * styleRuns, styleRunStart, &styleRunLimit, |
| * &width); |
| * ubidi_setLine(para, start, limit, line, pErrorCode); |
| * if(U_SUCCESS(*pErrorCode)) { |
| * // prepare rendering a new line |
| * // from either left or right |
| * startLine(paraLevel, width); |
| * |
| * renderLine(line, text, start, limit, |
| * styleRuns+styleRunStart, |
| * styleRunLimit-styleRunStart); |
| * } |
| * if(limit==length) { break; } |
| * start=limit; |
| * styleRunStart=styleRunLimit-1; |
| * if(start>=styleRuns[styleRunStart].limit) { |
| * ++styleRunStart; |
| * } |
| * } |
| * |
| * ubidi_close(line); |
| * } |
| * } |
| * } |
| * |
| * ubidi_close(para); |
| *} |
| *\endcode |
| * </pre> |
| */ |
| |
| /*DOCXX_TAG*/ |
| /*@{*/ |
| |
| /** |
| * UBiDiLevel is the type of the level values in this |
| * BiDi implementation. |
| * It holds an embedding level and indicates the visual direction |
| * by its bit 0 (even/odd value).<p> |
| * |
| * It can also hold non-level values for the |
| * <code>paraLevel</code> and <code>embeddingLevels</code> |
| * arguments of <code>ubidi_setPara()</code>; there: |
| * <ul> |
| * <li>bit 7 of an <code>embeddingLevels[]</code> |
| * value indicates whether the using application is |
| * specifying the level of a character to <i>override</i> whatever the |
| * BiDi implementation would resolve it to.</li> |
| * <li><code>paraLevel</code> can be set to the |
| * pseudo-level values <code>UBIDI_DEFAULT_LTR</code> |
| * and <code>UBIDI_DEFAULT_RTL</code>.</li> |
| * </ul> |
| * |
| * @see ubidi_setPara |
| * |
| * <p>The related constants are not real, valid level values. |
| * <code>UBIDI_DEFAULT_XXX</code> can be used to specify |
| * a default for the paragraph level for |
| * when the <code>ubidi_setPara()</code> function |
| * shall determine it but there is no |
| * strongly typed character in the input.<p> |
| * |
| * Note that the value for <code>UBIDI_DEFAULT_LTR</code> is even |
| * and the one for <code>UBIDI_DEFAULT_RTL</code> is odd, |
| * just like with normal LTR and RTL level values - |
| * these special values are designed that way. Also, the implementation |
| * assumes that UBIDI_MAX_EXPLICIT_LEVEL is odd. |
| * |
| * @see UBIDI_DEFAULT_LTR |
| * @see UBIDI_DEFAULT_RTL |
| * @see UBIDI_LEVEL_OVERRIDE |
| * @see UBIDI_MAX_EXPLICIT_LEVEL |
| * @stable ICU 2.0 |
| */ |
| typedef uint8_t UBiDiLevel; |
| |
| /** Paragraph level setting. |
| * If there is no strong character, then set the paragraph level to 0 (left-to-right). |
| * @stable ICU 2.0 |
| */ |
| #define UBIDI_DEFAULT_LTR 0xfe |
| |
| /** Paragraph level setting. |
| * If there is no strong character, then set the paragraph level to 1 (right-to-left). |
| * @stable ICU 2.0 |
| */ |
| #define UBIDI_DEFAULT_RTL 0xff |
| |
| /** |
| * Maximum explicit embedding level. |
| * (The maximum resolved level can be up to <code>UBIDI_MAX_EXPLICIT_LEVEL+1</code>). |
| * @stable ICU 2.0 |
| */ |
| #define UBIDI_MAX_EXPLICIT_LEVEL 61 |
| |
| /** Bit flag for level input. |
| * Overrides directional properties. |
| * @stable ICU 2.0 |
| */ |
| #define UBIDI_LEVEL_OVERRIDE 0x80 |
| |
| /** |
| * <code>UBiDiDirection</code> values indicate the text direction. |
| * @stable ICU 2.0 |
| */ |
| enum UBiDiDirection { |
| /** All left-to-right text. This is a 0 value. @stable ICU 2.0 */ |
| UBIDI_LTR, |
| /** All right-to-left text. This is a 1 value. @stable ICU 2.0 */ |
| UBIDI_RTL, |
| /** Mixed-directional text. @stable ICU 2.0 */ |
| UBIDI_MIXED |
| }; |
| |
| /** @stable ICU 2.0 */ |
| typedef enum UBiDiDirection UBiDiDirection; |
| |
| /** |
| * Forward declaration of the <code>UBiDi</code> structure for the declaration of |
| * the API functions. Its fields are implementation-specific.<p> |
| * This structure holds information about a paragraph (or multiple paragraphs) |
| * of text with BiDi-algorithm-related details, or about one line of |
| * such a paragraph.<p> |
| * Reordering can be done on a line, or on one or more paragraphs which are |
| * then interpreted each as one single line. |
| * @stable ICU 2.0 |
| */ |
| struct UBiDi; |
| |
| /** @stable ICU 2.0 */ |
| typedef struct UBiDi UBiDi; |
| |
| /** |
| * Allocate a <code>UBiDi</code> structure. |
| * Such an object is initially empty. It is assigned |
| * the BiDi properties of a piece of text containing one or more paragraphs |
| * by <code>ubidi_setPara()</code> |
| * or the BiDi properties of a line within a paragraph by |
| * <code>ubidi_setLine()</code>.<p> |
| * This object can be reused for as long as it is not deallocated |
| * by calling <code>ubidi_close()</code>.<p> |
| * <code>ubidi_setPara()</code> and <code>ubidi_setLine()</code> will allocate |
| * additional memory for internal structures as necessary. |
| * |
| * @return An empty <code>UBiDi</code> object. |
| * @stable ICU 2.0 |
| */ |
| U_STABLE UBiDi * U_EXPORT2 |
| ubidi_open(void); |
| |
| /** |
| * Allocate a <code>UBiDi</code> structure with preallocated memory |
| * for internal structures. |
| * This function provides a <code>UBiDi</code> object like <code>ubidi_open()</code> |
| * with no arguments, but it also preallocates memory for internal structures |
| * according to the sizings supplied by the caller.<p> |
| * Subsequent functions will not allocate any more memory, and are thus |
| * guaranteed not to fail because of lack of memory.<p> |
| * The preallocation can be limited to some of the internal memory |
| * by setting some values to 0 here. That means that if, e.g., |
| * <code>maxRunCount</code> cannot be reasonably predetermined and should not |
| * be set to <code>maxLength</code> (the only failproof value) to avoid |
| * wasting memory, then <code>maxRunCount</code> could be set to 0 here |
| * and the internal structures that are associated with it will be allocated |
| * on demand, just like with <code>ubidi_open()</code>. |
| * |
| * @param maxLength is the maximum text or line length that internal memory |
| * will be preallocated for. An attempt to associate this object with a |
| * longer text will fail, unless this value is 0, which leaves the allocation |
| * up to the implementation. |
| * |
| * @param maxRunCount is the maximum anticipated number of same-level runs |
| * that internal memory will be preallocated for. An attempt to access |
| * visual runs on an object that was not preallocated for as many runs |
| * as the text was actually resolved to will fail, |
| * unless this value is 0, which leaves the allocation up to the implementation.<p> |
| * The number of runs depends on the actual text and maybe anywhere between |
| * 1 and <code>maxLength</code>. It is typically small.<p> |
| * |
| * @param pErrorCode must be a valid pointer to an error code value. |
| * |
| * @return An empty <code>UBiDi</code> object with preallocated memory. |
| * @stable ICU 2.0 |
| */ |
| U_STABLE UBiDi * U_EXPORT2 |
| ubidi_openSized(int32_t maxLength, int32_t maxRunCount, UErrorCode *pErrorCode); |
| |
| /** |
| * <code>ubidi_close()</code> must be called to free the memory |
| * associated with a UBiDi object.<p> |
| * |
| * <strong>Important: </strong> |
| * A parent <code>UBiDi</code> object must not be destroyed or reused if |
| * it still has children. |
| * If a <code>UBiDi</code> object is the <i>child</i> |
| * of another one (its <i>parent</i>), after calling |
| * <code>ubidi_setLine()</code>, then the child object must |
| * be destroyed (closed) or reused (by calling |
| * <code>ubidi_setPara()</code> or <code>ubidi_setLine()</code>) |
| * before the parent object. |
| * |
| * @param pBiDi is a <code>UBiDi</code> object. |
| * |
| * @see ubidi_setPara |
| * @see ubidi_setLine |
| * @stable ICU 2.0 |
| */ |
| U_STABLE void U_EXPORT2 |
| ubidi_close(UBiDi *pBiDi); |
| |
| /** |
| * Modify the operation of the BiDi algorithm such that it |
| * approximates an "inverse BiDi" algorithm. This function |
| * must be called before <code>ubidi_setPara()</code>. |
| * |
| * <p>The normal operation of the BiDi algorithm as described |
| * in the Unicode Technical Report is to take text stored in logical |
| * (keyboard, typing) order and to determine the reordering of it for visual |
| * rendering. |
| * Some legacy systems store text in visual order, and for operations |
| * with standard, Unicode-based algorithms, the text needs to be transformed |
| * to logical order. This is effectively the inverse algorithm of the |
| * described BiDi algorithm. Note that there is no standard algorithm for |
| * this "inverse BiDi" and that the current implementation provides only an |
| * approximation of "inverse BiDi".</p> |
| * |
| * <p>With <code>isInverse</code> set to <code>TRUE</code>, |
| * this function changes the behavior of some of the subsequent functions |
| * in a way that they can be used for the inverse BiDi algorithm. |
| * Specifically, runs of text with numeric characters will be treated in a |
| * special way and may need to be surrounded with LRM characters when they are |
| * written in reordered sequence.</p> |
| * |
| * <p>Output runs should be retrieved using <code>ubidi_getVisualRun()</code>. |
| * Since the actual input for "inverse BiDi" is visually ordered text and |
| * <code>ubidi_getVisualRun()</code> gets the reordered runs, these are actually |
| * the runs of the logically ordered output.</p> |
| * |
| * @param pBiDi is a <code>UBiDi</code> object. |
| * |
| * @param isInverse specifies "forward" or "inverse" BiDi operation |
| * |
| * @see ubidi_setPara |
| * @see ubidi_writeReordered |
| * @stable ICU 2.0 |
| */ |
| U_STABLE void U_EXPORT2 |
| ubidi_setInverse(UBiDi *pBiDi, UBool isInverse); |
| |
| /** |
| * Is this BiDi object set to perform the inverse BiDi algorithm? |
| * |
| * @param pBiDi is a <code>UBiDi</code> object. |
| * @return TRUE if the BiDi object is set to perform the inverse BiDi algorithm |
| * |
| * @see ubidi_setInverse |
| * @stable ICU 2.0 |
| */ |
| |
| U_STABLE UBool U_EXPORT2 |
| ubidi_isInverse(UBiDi *pBiDi); |
| |
| /** |
| * Specify whether block separators must be allocated level zero, |
| * so that successive paragraphs will progress from left to right. |
| * This function must be called before <code>ubidi_setPara()</code>. |
| * Paragraph separators (B) may appear in the text. Setting them to level zero |
| * means that all paragraph separators (including one possibly appearing |
| * in the last text position) are kept in the reordered text after the text |
| * that they follow in the source text. |
| * When this feature is not enabled, a paragraph separator at the last |
| * position of the text before reordering will go to the first position |
| * of the reordered text when the paragraph level is odd. |
| * |
| * @param pBiDi is a <code>UBiDi</code> object. |
| * |
| * @param orderParagraphsLTR specifies whether paragraph separators (B) must |
| * receive level 0, so that successive paragraphs progress from left to right. |
| * |
| * @see ubidi_setPara |
| * @stable ICU 3.4 |
| */ |
| U_STABLE void U_EXPORT2 |
| ubidi_orderParagraphsLTR(UBiDi *pBiDi, UBool orderParagraphsLTR); |
| |
| /** |
| * Is this BiDi object set to allocate level 0 to block separators so that |
| * successive paragraphs progress from left to right? |
| * |
| * @param pBiDi is a <code>UBiDi</code> object. |
| * @return TRUE if the BiDi object is set to allocate level 0 to block |
| * separators. |
| * |
| * @see ubidi_orderParagraphsLTR |
| * @stable ICU 3.4 |
| */ |
| U_STABLE UBool U_EXPORT2 |
| ubidi_isOrderParagraphsLTR(UBiDi *pBiDi); |
| |
| /** |
| * Perform the Unicode BiDi algorithm. It is defined in the |
| * <a href="http://www.unicode.org/unicode/reports/tr9/">Unicode Standard Anned #9</a>, |
| * version 13, |
| * also described in The Unicode Standard, Version 4.0 .<p> |
| * |
| * This function takes a piece of plain text containing one or more paragraphs, |
| * with or without externally specified embedding levels from <i>styled</i> |
| * text and computes the left-right-directionality of each character.<p> |
| * |
| * If the entire text is all of the same directionality, then |
| * the function may not perform all the steps described by the algorithm, |
| * i.e., some levels may not be the same as if all steps were performed. |
| * This is not relevant for unidirectional text.<br> |
| * For example, in pure LTR text with numbers the numbers would get |
| * a resolved level of 2 higher than the surrounding text according to |
| * the algorithm. This implementation may set all resolved levels to |
| * the same value in such a case.<p> |
| * |
| * The text can be composed of multiple paragraphs. Occurrence of a block |
| * separator in the text terminates a paragraph, and whatever comes next starts |
| * a new paragraph. The exception to this rule is when a Carriage Return (CR) |
| * is followed by a Line Feed (LF). Both CR and LF are block separators, but |
| * in that case, the pair of characters is considered as terminating the |
| * preceding paragraph, and a new paragraph will be started by a character |
| * coming after the LF. |
| * |
| * @param pBiDi A <code>UBiDi</code> object allocated with <code>ubidi_open()</code> |
| * which will be set to contain the reordering information, |
| * especially the resolved levels for all the characters in <code>text</code>. |
| * |
| * @param text is a pointer to the text that the |
| * BiDi algorithm will be performed on |
| * <strong>The text must be (at least) <code>length</code> long.</strong> |
| * This pointer is stored in the UBiDi object and can be retrieved |
| * with <code>ubidi_getText()</code>. |
| * |
| * @param length is the length of the text; if <code>length==-1</code> then |
| * the text must be zero-terminated. |
| * |
| * @param paraLevel specifies the default level for the text; |
| * it is typically 0 (LTR) or 1 (RTL). |
| * If the function shall determine the paragraph level from the text, |
| * then <code>paraLevel</code> can be set to |
| * either <code>UBIDI_DEFAULT_LTR</code> |
| * or <code>UBIDI_DEFAULT_RTL</code>; if the text contains multiple |
| * paragraphs, the paragraph level shall be determined separately for |
| * each paragraph; if a paragraph does not include any strongly typed |
| * character, then the desired default is used (0 for LTR or 1 for RTL). |
| * Any other value between 0 and <code>UBIDI_MAX_EXPLICIT_LEVEL</code> is also valid, |
| * with odd levels indicating RTL. |
| * |
| * @param embeddingLevels (in) may be used to preset the embedding and override levels, |
| * ignoring characters like LRE and PDF in the text. |
| * A level overrides the directional property of its corresponding |
| * (same index) character if the level has the |
| * <code>UBIDI_LEVEL_OVERRIDE</code> bit set.<p> |
| * Except for that bit, it must be |
| * <code>paraLevel<=embeddingLevels[]<=UBIDI_MAX_EXPLICIT_LEVEL</code>, |
| * with one exception: a level of zero may be specified for a paragraph |
| * separator even if <code>paraLevel>0</code> when multiple paragraphs |
| * are submitted in the same call to <code>ubidi_setPara()</code>.<p> |
| * <strong>Caution: </strong>A copy of this pointer, not of the levels, |
| * will be stored in the <code>UBiDi</code> object; |
| * the <code>embeddingLevels</code> array must not be |
| * deallocated before the <code>UBiDi</code> structure is destroyed or reused, |
| * and the <code>embeddingLevels</code> |
| * should not be modified to avoid unexpected results on subsequent BiDi operations. |
| * However, the <code>ubidi_setPara()</code> and |
| * <code>ubidi_setLine()</code> functions may modify some or all of the levels.<p> |
| * After the <code>UBiDi</code> object is reused or destroyed, the caller |
| * must take care of the deallocation of the <code>embeddingLevels</code> array.<p> |
| * <strong>The <code>embeddingLevels</code> array must be |
| * at least <code>length</code> long.</strong> |
| * |
| * @param pErrorCode must be a valid pointer to an error code value. |
| * @stable ICU 2.0 |
| */ |
| U_STABLE void U_EXPORT2 |
| ubidi_setPara(UBiDi *pBiDi, const UChar *text, int32_t length, |
| UBiDiLevel paraLevel, UBiDiLevel *embeddingLevels, |
| UErrorCode *pErrorCode); |
| |
| /** |
| * <code>ubidi_setLine()</code> sets a <code>UBiDi</code> to |
| * contain the reordering information, especially the resolved levels, |
| * for all the characters in a line of text. This line of text is |
| * specified by referring to a <code>UBiDi</code> object representing |
| * this information for a piece of text containing one or more paragraphs, |
| * and by specifying a range of indexes in this text.<p> |
| * In the new line object, the indexes will range from 0 to <code>limit-start-1</code>.<p> |
| * |
| * This is used after calling <code>ubidi_setPara()</code> |
| * for a piece of text, and after line-breaking on that text. |
| * It is not necessary if each paragraph is treated as a single line.<p> |
| * |
| * After line-breaking, rules (L1) and (L2) for the treatment of |
| * trailing WS and for reordering are performed on |
| * a <code>UBiDi</code> object that represents a line.<p> |
| * |
| * <strong>Important: </strong><code>pLineBiDi</code> shares data with |
| * <code>pParaBiDi</code>. |
| * You must destroy or reuse <code>pLineBiDi</code> before <code>pParaBiDi</code>. |
| * In other words, you must destroy or reuse the <code>UBiDi</code> object for a line |
| * before the object for its parent paragraph.<p> |
| * |
| * The text pointer that was stored in <code>pParaBiDi</code> is also copied, |
| * and <code>start</code> is added to it so that it points to the beginning of the |
| * line for this object. |
| * |
| * @param pParaBiDi is the parent paragraph object. It must have been set |
| * by a successful call to ubidi_setPara. |
| * |
| * @param start is the line's first index into the text. |
| * |
| * @param limit is just behind the line's last index into the text |
| * (its last index +1).<br> |
| * It must be <code>0<=start<=limit<=</code>containing paragraph limit. |
| * If the specified line crosses a paragraph boundary, the function |
| * will terminate with error code U_ILLEGAL_ARGUMENT_ERROR. |
| * |
| * @param pLineBiDi is the object that will now represent a line of the text. |
| * |
| * @param pErrorCode must be a valid pointer to an error code value. |
| * |
| * @see ubidi_setPara |
| * @stable ICU 2.0 |
| */ |
| U_STABLE void U_EXPORT2 |
| ubidi_setLine(const UBiDi *pParaBiDi, |
| int32_t start, int32_t limit, |
| UBiDi *pLineBiDi, |
| UErrorCode *pErrorCode); |
| |
| /** |
| * Get the directionality of the text. |
| * |
| * @param pBiDi is the paragraph or line <code>UBiDi</code> object. |
| * |
| * @return A <code>UBIDI_XXX</code> value that indicates if the entire text |
| * represented by this object is unidirectional, |
| * and which direction, or if it is mixed-directional. |
| * |
| * @see UBiDiDirection |
| * @stable ICU 2.0 |
| */ |
| U_STABLE UBiDiDirection U_EXPORT2 |
| ubidi_getDirection(const UBiDi *pBiDi); |
| |
| /** |
| * Get the pointer to the text. |
| * |
| * @param pBiDi is the paragraph or line <code>UBiDi</code> object. |
| * |
| * @return The pointer to the text that the UBiDi object was created for. |
| * |
| * @see ubidi_setPara |
| * @see ubidi_setLine |
| * @stable ICU 2.0 |
| */ |
| U_STABLE const UChar * U_EXPORT2 |
| ubidi_getText(const UBiDi *pBiDi); |
| |
| /** |
| * Get the length of the text. |
| * |
| * @param pBiDi is the paragraph or line <code>UBiDi</code> object. |
| * |
| * @return The length of the text that the UBiDi object was created for. |
| * @stable ICU 2.0 |
| */ |
| U_STABLE int32_t U_EXPORT2 |
| ubidi_getLength(const UBiDi *pBiDi); |
| |
| /** |
| * Get the paragraph level of the text. |
| * |
| * @param pBiDi is the paragraph or line <code>UBiDi</code> object. |
| * |
| * @return The paragraph level. If there are multiple paragraphs, their |
| * level may vary if the required paraLevel is UBIDI_DEFAULT_LTR or |
| * UBIDI_DEFAULT_RTL. In that case, the level of the first paragraph |
| * is returned. |
| * |
| * @see UBiDiLevel |
| * @see ubidi_getParagraph |
| * @see ubidi_getParagraphByIndex |
| * @stable ICU 2.0 |
| */ |
| U_STABLE UBiDiLevel U_EXPORT2 |
| ubidi_getParaLevel(const UBiDi *pBiDi); |
| |
| /** |
| * Get the number of paragraphs. |
| * |
| * @param pBiDi is the paragraph or line <code>UBiDi</code> object. |
| * |
| * @return The number of paragraphs. |
| * @stable ICU 3.4 |
| */ |
| U_STABLE int32_t U_EXPORT2 |
| ubidi_countParagraphs(UBiDi *pBiDi); |
| |
| /** |
| * Get a paragraph, given a position within the text. |
| * This function returns information about a paragraph.<p> |
| * |
| * @param pBiDi is the paragraph or line <code>UBiDi</code> object. |
| * |
| * @param charIndex is the index of a character within the text, in the |
| * range <code>[0..ubidi_getLength(pBiDi)-1]</code>. |
| * |
| * @param pParaStart will receive the index of the first character of the |
| * paragraph in the text. |
| * This pointer can be <code>NULL</code> if this |
| * value is not necessary. |
| * |
| * @param pParaLimit will receive the limit of the paragraph. |
| * The l-value that you point to here may be the |
| * same expression (variable) as the one for |
| * <code>charIndex</code>. |
| * This pointer can be <code>NULL</code> if this |
| * value is not necessary. |
| * |
| * @param pParaLevel will receive the level of the paragraph. |
| * This pointer can be <code>NULL</code> if this |
| * value is not necessary. |
| * |
| * @param pErrorCode must be a valid pointer to an error code value. |
| * |
| * @return The index of the paragraph containing the specified position. |
| * @stable ICU 3.4 |
| */ |
| U_STABLE int32_t U_EXPORT2 |
| ubidi_getParagraph(const UBiDi *pBiDi, int32_t charIndex, int32_t *pParaStart, |
| int32_t *pParaLimit, UBiDiLevel *pParaLevel, |
| UErrorCode *pErrorCode); |
| |
| /** |
| * Get a paragraph, given the index of this paragraph. |
| * |
| * This function returns information about a paragraph.<p> |
| * |
| * @param pBiDi is the paragraph <code>UBiDi</code> object. |
| * |
| * @param paraIndex is the number of the paragraph, in the |
| * range <code>[0..ubidi_countParagraphs(pBiDi)-1]</code>. |
| * |
| * @param pParaStart will receive the index of the first character of the |
| * paragraph in the text. |
| * This pointer can be <code>NULL</code> if this |
| * value is not necessary. |
| * |
| * @param pParaLimit will receive the limit of the paragraph. |
| * This pointer can be <code>NULL</code> if this |
| * value is not necessary. |
| * |
| * @param pParaLevel will receive the level of the paragraph. |
| * This pointer can be <code>NULL</code> if this |
| * value is not necessary. |
| * |
| * @param pErrorCode must be a valid pointer to an error code value. |
| * |
| * @stable ICU 3.4 |
| */ |
| U_STABLE void U_EXPORT2 |
| ubidi_getParagraphByIndex(const UBiDi *pBiDi, int32_t paraIndex, |
| int32_t *pParaStart, int32_t *pParaLimit, |
| UBiDiLevel *pParaLevel, UErrorCode *pErrorCode); |
| |
| /** |
| * Get the level for one character. |
| * |
| * @param pBiDi is the paragraph or line <code>UBiDi</code> object. |
| * |
| * @param charIndex the index of a character. |
| * |
| * @return The level for the character at charIndex. |
| * |
| * @see UBiDiLevel |
| * @stable ICU 2.0 |
| */ |
| U_STABLE UBiDiLevel U_EXPORT2 |
| ubidi_getLevelAt(const UBiDi *pBiDi, int32_t charIndex); |
| |
| /** |
| * Get an array of levels for each character.<p> |
| * |
| * Note that this function may allocate memory under some |
| * circumstances, unlike <code>ubidi_getLevelAt()</code>. |
| * |
| * @param pBiDi is the paragraph or line <code>UBiDi</code> object, whose |
| * text length must be strictly positive. |
| * |
| * @param pErrorCode must be a valid pointer to an error code value. |
| * |
| * @return The levels array for the text, |
| * or <code>NULL</code> if an error occurs. |
| * |
| * @see UBiDiLevel |
| * @stable ICU 2.0 |
| */ |
| U_STABLE const UBiDiLevel * U_EXPORT2 |
| ubidi_getLevels(UBiDi *pBiDi, UErrorCode *pErrorCode); |
| |
| /** |
| * Get a logical run. |
| * This function returns information about a run and is used |
| * to retrieve runs in logical order.<p> |
| * This is especially useful for line-breaking on a paragraph. |
| * |
| * @param pBiDi is the paragraph or line <code>UBiDi</code> object. |
| * |
| * @param logicalStart is the first character of the run. |
| * |
| * @param pLogicalLimit will receive the limit of the run. |
| * The l-value that you point to here may be the |
| * same expression (variable) as the one for |
| * <code>logicalStart</code>. |
| * This pointer can be <code>NULL</code> if this |
| * value is not necessary. |
| * |
| * @param pLevel will receive the level of the run. |
| * This pointer can be <code>NULL</code> if this |
| * value is not necessary. |
| * @stable ICU 2.0 |
| */ |
| U_STABLE void U_EXPORT2 |
| ubidi_getLogicalRun(const UBiDi *pBiDi, int32_t logicalStart, |
| int32_t *pLogicalLimit, UBiDiLevel *pLevel); |
| |
| /** |
| * Get the number of runs. |
| * This function may invoke the actual reordering on the |
| * <code>UBiDi</code> object, after <code>ubidi_setPara()</code> |
| * may have resolved only the levels of the text. Therefore, |
| * <code>ubidi_countRuns()</code> may have to allocate memory, |
| * and may fail doing so. |
| * |
| * @param pBiDi is the paragraph or line <code>UBiDi</code> object. |
| * |
| * @param pErrorCode must be a valid pointer to an error code value. |
| * |
| * @return The number of runs. |
| * @stable ICU 2.0 |
| */ |
| U_STABLE int32_t U_EXPORT2 |
| ubidi_countRuns(UBiDi *pBiDi, UErrorCode *pErrorCode); |
| |
| /** |
| * Get one run's logical start, length, and directionality, |
| * which can be 0 for LTR or 1 for RTL. |
| * In an RTL run, the character at the logical start is |
| * visually on the right of the displayed run. |
| * The length is the number of characters in the run.<p> |
| * <code>ubidi_countRuns()</code> should be called |
| * before the runs are retrieved. |
| * |
| * @param pBiDi is the paragraph or line <code>UBiDi</code> object. |
| * |
| * @param runIndex is the number of the run in visual order, in the |
| * range <code>[0..ubidi_countRuns(pBiDi)-1]</code>. |
| * |
| * @param pLogicalStart is the first logical character index in the text. |
| * The pointer may be <code>NULL</code> if this index is not needed. |
| * |
| * @param pLength is the number of characters (at least one) in the run. |
| * The pointer may be <code>NULL</code> if this is not needed. |
| * |
| * @return the directionality of the run, |
| * <code>UBIDI_LTR==0</code> or <code>UBIDI_RTL==1</code>, |
| * never <code>UBIDI_MIXED</code>. |
| * |
| * @see ubidi_countRuns |
| * |
| * Example: |
| * <pre> |
| * \code |
| * int32_t i, count=ubidi_countRuns(pBiDi), |
| * logicalStart, visualIndex=0, length; |
| * for(i=0; i<count; ++i) { |
| * if(UBIDI_LTR==ubidi_getVisualRun(pBiDi, i, &logicalStart, &length)) { |
| * do { // LTR |
| * show_char(text[logicalStart++], visualIndex++); |
| * } while(--length>0); |
| * } else { |
| * logicalStart+=length; // logicalLimit |
| * do { // RTL |
| * show_char(text[--logicalStart], visualIndex++); |
| * } while(--length>0); |
| * } |
| * } |
| *\endcode |
| * </pre> |
| * |
| * Note that in right-to-left runs, code like this places |
| * modifier letters before base characters and second surrogates |
| * before first ones. |
| * @stable ICU 2.0 |
| */ |
| U_STABLE UBiDiDirection U_EXPORT2 |
| ubidi_getVisualRun(UBiDi *pBiDi, int32_t runIndex, |
| int32_t *pLogicalStart, int32_t *pLength); |
| |
| /** |
| * Get the visual position from a logical text position. |
| * If such a mapping is used many times on the same |
| * <code>UBiDi</code> object, then calling |
| * <code>ubidi_getLogicalMap()</code> is more efficient.<p> |
| * |
| * Note that in right-to-left runs, this mapping places |
| * modifier letters before base characters and second surrogates |
| * before first ones. |
| * |
| * @param pBiDi is the paragraph or line <code>UBiDi</code> object. |
| * |
| * @param logicalIndex is the index of a character in the text. |
| * |
| * @param pErrorCode must be a valid pointer to an error code value. |
| * |
| * @return The visual position of this character. |
| * |
| * @see ubidi_getLogicalMap |
| * @see ubidi_getLogicalIndex |
| * @stable ICU 2.0 |
| */ |
| U_STABLE int32_t U_EXPORT2 |
| ubidi_getVisualIndex(UBiDi *pBiDi, int32_t logicalIndex, UErrorCode *pErrorCode); |
| |
| /** |
| * Get the logical text position from a visual position. |
| * If such a mapping is used many times on the same |
| * <code>UBiDi</code> object, then calling |
| * <code>ubidi_getVisualMap()</code> is more efficient.<p> |
| * |
| * This is the inverse function to <code>ubidi_getVisualIndex()</code>. |
| * |
| * @param pBiDi is the paragraph or line <code>UBiDi</code> object. |
| * |
| * @param visualIndex is the visual position of a character. |
| * |
| * @param pErrorCode must be a valid pointer to an error code value. |
| * |
| * @return The index of this character in the text. |
| * |
| * @see ubidi_getVisualMap |
| * @see ubidi_getVisualIndex |
| * @stable ICU 2.0 |
| */ |
| U_STABLE int32_t U_EXPORT2 |
| ubidi_getLogicalIndex(UBiDi *pBiDi, int32_t visualIndex, UErrorCode *pErrorCode); |
| |
| /** |
| * Get a logical-to-visual index map (array) for the characters in the UBiDi |
| * (paragraph or line) object. |
| * |
| * @param pBiDi is the paragraph or line <code>UBiDi</code> object. |
| * |
| * @param indexMap is a pointer to an array of <code>ubidi_getLength()</code> |
| * indexes which will reflect the reordering of the characters. |
| * The array does not need to be initialized.<p> |
| * The index map will result in <code>indexMap[logicalIndex]==visualIndex</code>.<p> |
| * |
| * @param pErrorCode must be a valid pointer to an error code value. |
| * |
| * @see ubidi_getVisualMap |
| * @see ubidi_getVisualIndex |
| * @stable ICU 2.0 |
| */ |
| U_STABLE void U_EXPORT2 |
| ubidi_getLogicalMap(UBiDi *pBiDi, int32_t *indexMap, UErrorCode *pErrorCode); |
| |
| /** |
| * Get a visual-to-logical index map (array) for the characters in the UBiDi |
| * (paragraph or line) object. |
| * |
| * @param pBiDi is the paragraph or line <code>UBiDi</code> object. |
| * |
| * @param indexMap is a pointer to an array of <code>ubidi_getLength()</code> |
| * indexes which will reflect the reordering of the characters. |
| * The array does not need to be initialized.<p> |
| * The index map will result in <code>indexMap[visualIndex]==logicalIndex</code>.<p> |
| * |
| * @param pErrorCode must be a valid pointer to an error code value. |
| * |
| * @see ubidi_getLogicalMap |
| * @see ubidi_getLogicalIndex |
| * @stable ICU 2.0 |
| */ |
| U_STABLE void U_EXPORT2 |
| ubidi_getVisualMap(UBiDi *pBiDi, int32_t *indexMap, UErrorCode *pErrorCode); |
| |
| /** |
| * This is a convenience function that does not use a UBiDi object. |
| * It is intended to be used for when an application has determined the levels |
| * of objects (character sequences) and just needs to have them reordered (L2). |
| * This is equivalent to using <code>ubidi_getLogicalMap</code> on a |
| * <code>UBiDi</code> object. |
| * |
| * @param levels is an array with <code>length</code> levels that have been determined by |
| * the application. |
| * |
| * @param length is the number of levels in the array, or, semantically, |
| * the number of objects to be reordered. |
| * It must be <code>length>0</code>. |
| * |
| * @param indexMap is a pointer to an array of <code>length</code> |
| * indexes which will reflect the reordering of the characters. |
| * The array does not need to be initialized.<p> |
| * The index map will result in <code>indexMap[logicalIndex]==visualIndex</code>. |
| * @stable ICU 2.0 |
| */ |
| U_STABLE void U_EXPORT2 |
| ubidi_reorderLogical(const UBiDiLevel *levels, int32_t length, int32_t *indexMap); |
| |
| /** |
| * This is a convenience function that does not use a UBiDi object. |
| * It is intended to be used for when an application has determined the levels |
| * of objects (character sequences) and just needs to have them reordered (L2). |
| * This is equivalent to using <code>ubidi_getVisualMap</code> on a |
| * <code>UBiDi</code> object. |
| * |
| * @param levels is an array with <code>length</code> levels that have been determined by |
| * the application. |
| * |
| * @param length is the number of levels in the array, or, semantically, |
| * the number of objects to be reordered. |
| * It must be <code>length>0</code>. |
| * |
| * @param indexMap is a pointer to an array of <code>length</code> |
| * indexes which will reflect the reordering of the characters. |
| * The array does not need to be initialized.<p> |
| * The index map will result in <code>indexMap[visualIndex]==logicalIndex</code>. |
| * @stable ICU 2.0 |
| */ |
| U_STABLE void U_EXPORT2 |
| ubidi_reorderVisual(const UBiDiLevel *levels, int32_t length, int32_t *indexMap); |
| |
| /** |
| * Invert an index map. |
| * The one-to-one index mapping of the first map is inverted and written to |
| * the second one. |
| * |
| * @param srcMap is an array with <code>length</code> indexes |
| * which define the original mapping. |
| * |
| * @param destMap is an array with <code>length</code> indexes |
| * which will be filled with the inverse mapping. |
| * |
| * @param length is the length of each array. |
| * @stable ICU 2.0 |
| */ |
| U_STABLE void U_EXPORT2 |
| ubidi_invertMap(const int32_t *srcMap, int32_t *destMap, int32_t length); |
| |
| /** option flags for ubidi_writeReordered() */ |
| |
| /** |
| * option bit for ubidi_writeReordered(): |
| * keep combining characters after their base characters in RTL runs |
| * |
| * @see ubidi_writeReordered |
| * @stable ICU 2.0 |
| */ |
| #define UBIDI_KEEP_BASE_COMBINING 1 |
| |
| /** |
| * option bit for ubidi_writeReordered(): |
| * replace characters with the "mirrored" property in RTL runs |
| * by their mirror-image mappings |
| * |
| * @see ubidi_writeReordered |
| * @stable ICU 2.0 |
| */ |
| #define UBIDI_DO_MIRRORING 2 |
| |
| /** |
| * option bit for ubidi_writeReordered(): |
| * surround the run with LRMs if necessary; |
| * this is part of the approximate "inverse BiDi" algorithm |
| * |
| * @see ubidi_setInverse |
| * @see ubidi_writeReordered |
| * @stable ICU 2.0 |
| */ |
| #define UBIDI_INSERT_LRM_FOR_NUMERIC 4 |
| |
| /** |
| * option bit for ubidi_writeReordered(): |
| * remove BiDi control characters |
| * (this does not affect UBIDI_INSERT_LRM_FOR_NUMERIC) |
| * |
| * @see ubidi_writeReordered |
| * @stable ICU 2.0 |
| */ |
| #define UBIDI_REMOVE_BIDI_CONTROLS 8 |
| |
| /** |
| * option bit for ubidi_writeReordered(): |
| * write the output in reverse order |
| * |
| * <p>This has the same effect as calling <code>ubidi_writeReordered()</code> |
| * first without this option, and then calling |
| * <code>ubidi_writeReverse()</code> without mirroring. |
| * Doing this in the same step is faster and avoids a temporary buffer. |
| * An example for using this option is output to a character terminal that |
| * is designed for RTL scripts and stores text in reverse order.</p> |
| * |
| * @see ubidi_writeReordered |
| * @stable ICU 2.0 |
| */ |
| #define UBIDI_OUTPUT_REVERSE 16 |
| |
| /** |
| * Take a <code>UBiDi</code> object containing the reordering |
| * information for a piece of text (one or more paragraphs) set by |
| * <code>ubidi_setPara()</code> or for a line of text set by <code>ubidi_setLine()</code> |
| * and write a reordered string to the destination buffer. |
| * |
| * This function preserves the integrity of characters with multiple |
| * code units and (optionally) modifier letters. |
| * Characters in RTL runs can be replaced by mirror-image characters |
| * in the destination buffer. Note that "real" mirroring has |
| * to be done in a rendering engine by glyph selection |
| * and that for many "mirrored" characters there are no |
| * Unicode characters as mirror-image equivalents. |
| * There are also options to insert or remove BiDi control |
| * characters; see the description of the <code>destSize</code> |
| * and <code>options</code> parameters and of the option bit flags. |
| * |
| * @see UBIDI_DO_MIRRORING |
| * @see UBIDI_INSERT_LRM_FOR_NUMERIC |
| * @see UBIDI_KEEP_BASE_COMBINING |
| * @see UBIDI_OUTPUT_REVERSE |
| * @see UBIDI_REMOVE_BIDI_CONTROLS |
| * |
| * @param pBiDi A pointer to a <code>UBiDi</code> object that |
| * is set by <code>ubidi_setPara()</code> or |
| * <code>ubidi_setLine()</code> and contains the reordering |
| * information for the text that it was defined for, |
| * as well as a pointer to that text. |
| * <p>The text was aliased (only the pointer was stored |
| * without copying the contents) and must not have been modified |
| * since the <code>ubidi_setPara()</code> call.</p> |
| * |
| * @param dest A pointer to where the reordered text is to be copied. |
| * The source text and <code>dest[destSize]</code> |
| * must not overlap. |
| * |
| * @param destSize The size of the <code>dest</code> buffer, |
| * in number of UChars. |
| * If the <code>UBIDI_INSERT_LRM_FOR_NUMERIC</code> |
| * option is set, then the destination length could be |
| * as large as |
| * <code>ubidi_getLength(pBiDi)+2*ubidi_countRuns(pBiDi)</code>. |
| * If the <code>UBIDI_REMOVE_BIDI_CONTROLS</code> option |
| * is set, then the destination length may be less than |
| * <code>ubidi_getLength(pBiDi)</code>. |
| * If none of these options is set, then the destination length |
| * will be exactly <code>ubidi_getLength(pBiDi)</code>. |
| * |
| * @param options A bit set of options for the reordering that control |
| * how the reordered text is written. |
| * The options include mirroring the characters on a code |
| * point basis and inserting LRM characters, which is used |
| * especially for transforming visually stored text |
| * to logically stored text (although this is still an |
| * imperfect implementation of an "inverse BiDi" algorithm |
| * because it uses the "forward BiDi" algorithm at its core). |
| * The available options are: |
| * <code>#UBIDI_DO_MIRRORING</code>, |
| * <code>#UBIDI_INSERT_LRM_FOR_NUMERIC</code>, |
| * <code>#UBIDI_KEEP_BASE_COMBINING</code>, |
| * <code>#UBIDI_OUTPUT_REVERSE</code>, |
| * <code>#UBIDI_REMOVE_BIDI_CONTROLS</code> |
| * |
| * @param pErrorCode must be a valid pointer to an error code value. |
| * |
| * @return The length of the output string. |
| * @stable ICU 2.0 |
| */ |
| U_STABLE int32_t U_EXPORT2 |
| ubidi_writeReordered(UBiDi *pBiDi, |
| UChar *dest, int32_t destSize, |
| uint16_t options, |
| UErrorCode *pErrorCode); |
| |
| /** |
| * Reverse a Right-To-Left run of Unicode text. |
| * |
| * This function preserves the integrity of characters with multiple |
| * code units and (optionally) modifier letters. |
| * Characters can be replaced by mirror-image characters |
| * in the destination buffer. Note that "real" mirroring has |
| * to be done in a rendering engine by glyph selection |
| * and that for many "mirrored" characters there are no |
| * Unicode characters as mirror-image equivalents. |
| * There are also options to insert or remove BiDi control |
| * characters. |
| * |
| * This function is the implementation for reversing RTL runs as part |
| * of <code>ubidi_writeReordered()</code>. For detailed descriptions |
| * of the parameters, see there. |
| * Since no BiDi controls are inserted here, the output string length |
| * will never exceed <code>srcLength</code>. |
| * |
| * @see ubidi_writeReordered |
| * |
| * @param src A pointer to the RTL run text. |
| * |
| * @param srcLength The length of the RTL run. |
| * |
| * @param dest A pointer to where the reordered text is to be copied. |
| * <code>src[srcLength]</code> and <code>dest[destSize]</code> |
| * must not overlap. |
| * |
| * @param destSize The size of the <code>dest</code> buffer, |
| * in number of UChars. |
| * If the <code>UBIDI_REMOVE_BIDI_CONTROLS</code> option |
| * is set, then the destination length may be less than |
| * <code>srcLength</code>. |
| * If this option is not set, then the destination length |
| * will be exactly <code>srcLength</code>. |
| * |
| * @param options A bit set of options for the reordering that control |
| * how the reordered text is written. |
| * See the <code>options</code> parameter in <code>ubidi_writeReordered()</code>. |
| * |
| * @param pErrorCode must be a valid pointer to an error code value. |
| * |
| * @return The length of the output string. |
| * @stable ICU 2.0 |
| */ |
| U_STABLE int32_t U_EXPORT2 |
| ubidi_writeReverse(const UChar *src, int32_t srcLength, |
| UChar *dest, int32_t destSize, |
| uint16_t options, |
| UErrorCode *pErrorCode); |
| |
| /*#define BIDI_SAMPLE_CODE*/ |
| /*@}*/ |
| |
| #endif |