| /* |
| ****************************************************************************** |
| * |
| * Copyright (C) 1999-2011, 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, updated by Matitiahu Allouche |
| */ |
| |
| #ifndef UBIDI_H |
| #define UBIDI_H |
| |
| #include "unicode/utypes.h" |
| #include "unicode/uchar.h" |
| #include "unicode/localpointer.h" |
| |
| /** |
| *\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>.<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.<p> |
| * |
| * Constant indicating that the base direction depends on the first strong |
| * directional character in the text according to the Unicode Bidirectional |
| * Algorithm. If no strong directional character is present, |
| * then set the paragraph level to 0 (left-to-right).<p> |
| * |
| * If this value is used in conjunction with reordering modes |
| * <code>UBIDI_REORDER_INVERSE_LIKE_DIRECT</code> or |
| * <code>UBIDI_REORDER_INVERSE_FOR_NUMBERS_SPECIAL</code>, the text to reorder |
| * is assumed to be visual LTR, and the text after reordering is required |
| * to be the corresponding logical string with appropriate contextual |
| * direction. The direction of the result string will be RTL if either |
| * the righmost or leftmost strong character of the source text is RTL |
| * or Arabic Letter, the direction will be LTR otherwise.<p> |
| * |
| * If reordering option <code>UBIDI_OPTION_INSERT_MARKS</code> is set, an RLM may |
| * be added at the beginning of the result string to ensure round trip |
| * (that the result string, when reordered back to visual, will produce |
| * the original source text). |
| * @see UBIDI_REORDER_INVERSE_LIKE_DIRECT |
| * @see UBIDI_REORDER_INVERSE_FOR_NUMBERS_SPECIAL |
| * @stable ICU 2.0 |
| */ |
| #define UBIDI_DEFAULT_LTR 0xfe |
| |
| /** Paragraph level setting.<p> |
| * |
| * Constant indicating that the base direction depends on the first strong |
| * directional character in the text according to the Unicode Bidirectional |
| * Algorithm. If no strong directional character is present, |
| * then set the paragraph level to 1 (right-to-left).<p> |
| * |
| * If this value is used in conjunction with reordering modes |
| * <code>UBIDI_REORDER_INVERSE_LIKE_DIRECT</code> or |
| * <code>UBIDI_REORDER_INVERSE_FOR_NUMBERS_SPECIAL</code>, the text to reorder |
| * is assumed to be visual LTR, and the text after reordering is required |
| * to be the corresponding logical string with appropriate contextual |
| * direction. The direction of the result string will be RTL if either |
| * the righmost or leftmost strong character of the source text is RTL |
| * or Arabic Letter, or if the text contains no strong character; |
| * the direction will be LTR otherwise.<p> |
| * |
| * If reordering option <code>UBIDI_OPTION_INSERT_MARKS</code> is set, an RLM may |
| * be added at the beginning of the result string to ensure round trip |
| * (that the result string, when reordered back to visual, will produce |
| * the original source text). |
| * @see UBIDI_REORDER_INVERSE_LIKE_DIRECT |
| * @see UBIDI_REORDER_INVERSE_FOR_NUMBERS_SPECIAL |
| * @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 |
| |
| /** |
| * Special value which can be returned by the mapping functions when a logical |
| * index has no corresponding visual index or vice-versa. This may happen |
| * for the logical-to-visual mapping of a Bidi control when option |
| * <code>#UBIDI_OPTION_REMOVE_CONTROLS</code> is specified. This can also happen |
| * for the visual-to-logical mapping of a Bidi mark (LRM or RLM) inserted |
| * by option <code>#UBIDI_OPTION_INSERT_MARKS</code>. |
| * @see ubidi_getVisualIndex |
| * @see ubidi_getVisualMap |
| * @see ubidi_getLogicalIndex |
| * @see ubidi_getLogicalMap |
| * @stable ICU 3.6 |
| */ |
| #define UBIDI_MAP_NOWHERE (-1) |
| |
| /** |
| * <code>UBiDiDirection</code> values indicate the text direction. |
| * @stable ICU 2.0 |
| */ |
| enum UBiDiDirection { |
| /** Left-to-right text. This is a 0 value. |
| * <ul> |
| * <li>As return value for <code>ubidi_getDirection()</code>, it means |
| * that the source string contains no right-to-left characters, or |
| * that the source string is empty and the paragraph level is even. |
| * <li> As return value for <code>ubidi_getBaseDirection()</code>, it |
| * means that the first strong character of the source string has |
| * a left-to-right direction. |
| * </ul> |
| * @stable ICU 2.0 |
| */ |
| UBIDI_LTR, |
| /** Right-to-left text. This is a 1 value. |
| * <ul> |
| * <li>As return value for <code>ubidi_getDirection()</code>, it means |
| * that the source string contains no left-to-right characters, or |
| * that the source string is empty and the paragraph level is odd. |
| * <li> As return value for <code>ubidi_getBaseDirection()</code>, it |
| * means that the first strong character of the source string has |
| * a right-to-left direction. |
| * </ul> |
| * @stable ICU 2.0 |
| */ |
| UBIDI_RTL, |
| /** Mixed-directional text. |
| * <p>As return value for <code>ubidi_getDirection()</code>, it means |
| * that the source string contains both left-to-right and |
| * right-to-left characters. |
| * @stable ICU 2.0 |
| */ |
| UBIDI_MIXED, |
| /** No strongly directional text. |
| * <p>As return value for <code>ubidi_getBaseDirection()</code>, it means |
| * that the source string is missing or empty, or contains neither left-to-right |
| * nor right-to-left characters. |
| * @draft ICU 4.6 |
| */ |
| UBIDI_NEUTRAL |
| }; |
| |
| /** @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.<br><br> |
| * The number of runs depends on the actual text and maybe anywhere between |
| * 1 and <code>maxLength</code>. It is typically small. |
| * |
| * @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 has become the <i>child</i> |
| * of another one (its <i>parent</i>) by 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); |
| |
| #if U_SHOW_CPLUSPLUS_API |
| |
| U_NAMESPACE_BEGIN |
| |
| /** |
| * \class LocalUBiDiPointer |
| * "Smart pointer" class, closes a UBiDi via ubidi_close(). |
| * For most methods see the LocalPointerBase base class. |
| * |
| * @see LocalPointerBase |
| * @see LocalPointer |
| * @stable ICU 4.4 |
| */ |
| U_DEFINE_LOCAL_OPEN_POINTER(LocalUBiDiPointer, UBiDi, ubidi_close); |
| |
| U_NAMESPACE_END |
| |
| #endif |
| |
| /** |
| * 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> |
| * |
| * <p>Calling this function with argument <code>isInverse</code> set to |
| * <code>TRUE</code> is equivalent to calling |
| * <code>ubidi_setReorderingMode</code> with argument |
| * <code>reorderingMode</code> |
| * set to <code>#UBIDI_REORDER_INVERSE_NUMBERS_AS_L</code>.<br> |
| * Calling this function with argument <code>isInverse</code> set to |
| * <code>FALSE</code> is equivalent to calling |
| * <code>ubidi_setReorderingMode</code> with argument |
| * <code>reorderingMode</code> |
| * set to <code>#UBIDI_REORDER_DEFAULT</code>. |
| * |
| * @param pBiDi is a <code>UBiDi</code> object. |
| * |
| * @param isInverse specifies "forward" or "inverse" Bidi operation. |
| * |
| * @see ubidi_setPara |
| * @see ubidi_writeReordered |
| * @see ubidi_setReorderingMode |
| * @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? |
| * <p>Note: calling this function after setting the reordering mode with |
| * <code>ubidi_setReorderingMode</code> will return <code>TRUE</code> if the |
| * reordering mode was set to <code>#UBIDI_REORDER_INVERSE_NUMBERS_AS_L</code>, |
| * <code>FALSE</code> for all other values.</p> |
| * |
| * @param pBiDi is a <code>UBiDi</code> object. |
| * @return TRUE if the Bidi object is set to perform the inverse Bidi algorithm |
| * by handling numbers as L. |
| * |
| * @see ubidi_setInverse |
| * @see ubidi_setReorderingMode |
| * @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); |
| |
| /** |
| * <code>UBiDiReorderingMode</code> values indicate which variant of the Bidi |
| * algorithm to use. |
| * |
| * @see ubidi_setReorderingMode |
| * @stable ICU 3.6 |
| */ |
| typedef enum UBiDiReorderingMode { |
| /** Regular Logical to Visual Bidi algorithm according to Unicode. |
| * This is a 0 value. |
| * @stable ICU 3.6 */ |
| UBIDI_REORDER_DEFAULT = 0, |
| /** Logical to Visual algorithm which handles numbers in a way which |
| * mimicks the behavior of Windows XP. |
| * @stable ICU 3.6 */ |
| UBIDI_REORDER_NUMBERS_SPECIAL, |
| /** Logical to Visual algorithm grouping numbers with adjacent R characters |
| * (reversible algorithm). |
| * @stable ICU 3.6 */ |
| UBIDI_REORDER_GROUP_NUMBERS_WITH_R, |
| /** Reorder runs only to transform a Logical LTR string to the Logical RTL |
| * string with the same display, or vice-versa.<br> |
| * If this mode is set together with option |
| * <code>#UBIDI_OPTION_INSERT_MARKS</code>, some Bidi controls in the source |
| * text may be removed and other controls may be added to produce the |
| * minimum combination which has the required display. |
| * @stable ICU 3.6 */ |
| UBIDI_REORDER_RUNS_ONLY, |
| /** Visual to Logical algorithm which handles numbers like L |
| * (same algorithm as selected by <code>ubidi_setInverse(TRUE)</code>. |
| * @see ubidi_setInverse |
| * @stable ICU 3.6 */ |
| UBIDI_REORDER_INVERSE_NUMBERS_AS_L, |
| /** Visual to Logical algorithm equivalent to the regular Logical to Visual |
| * algorithm. |
| * @stable ICU 3.6 */ |
| UBIDI_REORDER_INVERSE_LIKE_DIRECT, |
| /** Inverse Bidi (Visual to Logical) algorithm for the |
| * <code>UBIDI_REORDER_NUMBERS_SPECIAL</code> Bidi algorithm. |
| * @stable ICU 3.6 */ |
| UBIDI_REORDER_INVERSE_FOR_NUMBERS_SPECIAL, |
| /** Number of values for reordering mode. |
| * @stable ICU 3.6 */ |
| UBIDI_REORDER_COUNT |
| } UBiDiReorderingMode; |
| |
| /** |
| * Modify the operation of the Bidi algorithm such that it implements some |
| * variant to the basic Bidi algorithm or approximates an "inverse Bidi" |
| * algorithm, depending on different values of the "reordering mode". |
| * This function must be called before <code>ubidi_setPara()</code>, and stays |
| * in effect until called again with a different argument. |
| * |
| * <p>The normal operation of the Bidi algorithm as described |
| * in the Unicode Standard Annex #9 is to take text stored in logical |
| * (keyboard, typing) order and to determine how to reorder it for visual |
| * rendering.</p> |
| * |
| * <p>With the reordering mode set to a value other than |
| * <code>#UBIDI_REORDER_DEFAULT</code>, this function changes the behavior of |
| * some of the subsequent functions in a way such that they implement an |
| * inverse Bidi algorithm or some other algorithm variants.</p> |
| * |
| * <p>Some legacy systems store text in visual order, and for operations |
| * with standard, Unicode-based algorithms, the text needs to be transformed |
| * into logical order. This is effectively the inverse algorithm of the |
| * described Bidi algorithm. Note that there is no standard algorithm for |
| * this "inverse Bidi", so a number of variants are implemented here.</p> |
| * |
| * <p>In other cases, it may be desirable to emulate some variant of the |
| * Logical to Visual algorithm (e.g. one used in MS Windows), or perform a |
| * Logical to Logical transformation.</p> |
| * |
| * <ul> |
| * <li>When the reordering mode is set to <code>#UBIDI_REORDER_DEFAULT</code>, |
| * the standard Bidi Logical to Visual algorithm is applied.</li> |
| * |
| * <li>When the reordering mode is set to |
| * <code>#UBIDI_REORDER_NUMBERS_SPECIAL</code>, |
| * the algorithm used to perform Bidi transformations when calling |
| * <code>ubidi_setPara</code> should approximate the algorithm used in |
| * Microsoft Windows XP rather than strictly conform to the Unicode Bidi |
| * algorithm. |
| * <br> |
| * The differences between the basic algorithm and the algorithm addressed |
| * by this option are as follows: |
| * <ul> |
| * <li>Within text at an even embedding level, the sequence "123AB" |
| * (where AB represent R or AL letters) is transformed to "123BA" by the |
| * Unicode algorithm and to "BA123" by the Windows algorithm.</li> |
| * <li>Arabic-Indic numbers (AN) are handled by the Windows algorithm just |
| * like regular numbers (EN).</li> |
| * </ul></li> |
| * |
| * <li>When the reordering mode is set to |
| * <code>#UBIDI_REORDER_GROUP_NUMBERS_WITH_R</code>, |
| * numbers located between LTR text and RTL text are associated with the RTL |
| * text. For instance, an LTR paragraph with content "abc 123 DEF" (where |
| * upper case letters represent RTL characters) will be transformed to |
| * "abc FED 123" (and not "abc 123 FED"), "DEF 123 abc" will be transformed |
| * to "123 FED abc" and "123 FED abc" will be transformed to "DEF 123 abc". |
| * This makes the algorithm reversible and makes it useful when round trip |
| * (from visual to logical and back to visual) must be achieved without |
| * adding LRM characters. However, this is a variation from the standard |
| * Unicode Bidi algorithm.<br> |
| * The source text should not contain Bidi control characters other than LRM |
| * or RLM.</li> |
| * |
| * <li>When the reordering mode is set to |
| * <code>#UBIDI_REORDER_RUNS_ONLY</code>, |
| * a "Logical to Logical" transformation must be performed: |
| * <ul> |
| * <li>If the default text level of the source text (argument <code>paraLevel</code> |
| * in <code>ubidi_setPara</code>) is even, the source text will be handled as |
| * LTR logical text and will be transformed to the RTL logical text which has |
| * the same LTR visual display.</li> |
| * <li>If the default level of the source text is odd, the source text |
| * will be handled as RTL logical text and will be transformed to the |
| * LTR logical text which has the same LTR visual display.</li> |
| * </ul> |
| * This mode may be needed when logical text which is basically Arabic or |
| * Hebrew, with possible included numbers or phrases in English, has to be |
| * displayed as if it had an even embedding level (this can happen if the |
| * displaying application treats all text as if it was basically LTR). |
| * <br> |
| * This mode may also be needed in the reverse case, when logical text which is |
| * basically English, with possible included phrases in Arabic or Hebrew, has to |
| * be displayed as if it had an odd embedding level. |
| * <br> |
| * Both cases could be handled by adding LRE or RLE at the head of the text, |
| * if the display subsystem supports these formatting controls. If it does not, |
| * the problem may be handled by transforming the source text in this mode |
| * before displaying it, so that it will be displayed properly.<br> |
| * The source text should not contain Bidi control characters other than LRM |
| * or RLM.</li> |
| * |
| * <li>When the reordering mode is set to |
| * <code>#UBIDI_REORDER_INVERSE_NUMBERS_AS_L</code>, an "inverse Bidi" algorithm |
| * is applied. |
| * Runs of text with numeric characters will be treated like LTR letters and |
| * may need to be surrounded with LRM characters when they are written in |
| * reordered sequence (the option <code>#UBIDI_INSERT_LRM_FOR_NUMERIC</code> can |
| * be used with function <code>ubidi_writeReordered</code> to this end. This |
| * mode is equivalent to calling <code>ubidi_setInverse()</code> with |
| * argument <code>isInverse</code> set to <code>TRUE</code>.</li> |
| * |
| * <li>When the reordering mode is set to |
| * <code>#UBIDI_REORDER_INVERSE_LIKE_DIRECT</code>, the "direct" Logical to Visual |
| * Bidi algorithm is used as an approximation of an "inverse Bidi" algorithm. |
| * This mode is similar to mode <code>#UBIDI_REORDER_INVERSE_NUMBERS_AS_L</code> |
| * but is closer to the regular Bidi algorithm. |
| * <br> |
| * For example, an LTR paragraph with the content "FED 123 456 CBA" (where |
| * upper case represents RTL characters) will be transformed to |
| * "ABC 456 123 DEF", as opposed to "DEF 123 456 ABC" |
| * with mode <code>UBIDI_REORDER_INVERSE_NUMBERS_AS_L</code>.<br> |
| * When used in conjunction with option |
| * <code>#UBIDI_OPTION_INSERT_MARKS</code>, this mode generally |
| * adds Bidi marks to the output significantly more sparingly than mode |
| * <code>#UBIDI_REORDER_INVERSE_NUMBERS_AS_L</code> with option |
| * <code>#UBIDI_INSERT_LRM_FOR_NUMERIC</code> in calls to |
| * <code>ubidi_writeReordered</code>.</li> |
| * |
| * <li>When the reordering mode is set to |
| * <code>#UBIDI_REORDER_INVERSE_FOR_NUMBERS_SPECIAL</code>, the Logical to Visual |
| * Bidi algorithm used in Windows XP is used as an approximation of an "inverse Bidi" algorithm. |
| * <br> |
| * For example, an LTR paragraph with the content "abc FED123" (where |
| * upper case represents RTL characters) will be transformed to "abc 123DEF."</li> |
| * </ul> |
| * |
| * <p>In all the reordering modes specifying an "inverse Bidi" algorithm |
| * (i.e. those with a name starting with <code>UBIDI_REORDER_INVERSE</code>), |
| * output runs should be retrieved using |
| * <code>ubidi_getVisualRun()</code>, and the output text with |
| * <code>ubidi_writeReordered()</code>. The caller should keep in mind that in |
| * "inverse Bidi" modes the input is actually visually ordered text and |
| * reordered output returned by <code>ubidi_getVisualRun()</code> or |
| * <code>ubidi_writeReordered()</code> are actually runs or character string |
| * of logically ordered output.<br> |
| * For all the "inverse Bidi" modes, the source text should not contain |
| * Bidi control characters other than LRM or RLM.</p> |
| * |
| * <p>Note that option <code>#UBIDI_OUTPUT_REVERSE</code> of |
| * <code>ubidi_writeReordered</code> has no useful meaning and should not be |
| * used in conjunction with any value of the reordering mode specifying |
| * "inverse Bidi" or with value <code>UBIDI_REORDER_RUNS_ONLY</code>. |
| * |
| * @param pBiDi is a <code>UBiDi</code> object. |
| * @param reorderingMode specifies the required variant of the Bidi algorithm. |
| * |
| * @see UBiDiReorderingMode |
| * @see ubidi_setInverse |
| * @see ubidi_setPara |
| * @see ubidi_writeReordered |
| * @stable ICU 3.6 |
| */ |
| U_STABLE void U_EXPORT2 |
| ubidi_setReorderingMode(UBiDi *pBiDi, UBiDiReorderingMode reorderingMode); |
| |
| /** |
| * What is the requested reordering mode for a given Bidi object? |
| * |
| * @param pBiDi is a <code>UBiDi</code> object. |
| * @return the current reordering mode of the Bidi object |
| * @see ubidi_setReorderingMode |
| * @stable ICU 3.6 |
| */ |
| U_STABLE UBiDiReorderingMode U_EXPORT2 |
| ubidi_getReorderingMode(UBiDi *pBiDi); |
| |
| /** |
| * <code>UBiDiReorderingOption</code> values indicate which options are |
| * specified to affect the Bidi algorithm. |
| * |
| * @see ubidi_setReorderingOptions |
| * @stable ICU 3.6 |
| */ |
| typedef enum UBiDiReorderingOption { |
| /** |
| * option value for <code>ubidi_setReorderingOptions</code>: |
| * disable all the options which can be set with this function |
| * @see ubidi_setReorderingOptions |
| * @stable ICU 3.6 |
| */ |
| UBIDI_OPTION_DEFAULT = 0, |
| |
| /** |
| * option bit for <code>ubidi_setReorderingOptions</code>: |
| * insert Bidi marks (LRM or RLM) when needed to ensure correct result of |
| * a reordering to a Logical order |
| * |
| * <p>This option must be set or reset before calling |
| * <code>ubidi_setPara</code>.</p> |
| * |
| * <p>This option is significant only with reordering modes which generate |
| * a result with Logical order, specifically:</p> |
| * <ul> |
| * <li><code>#UBIDI_REORDER_RUNS_ONLY</code></li> |
| * <li><code>#UBIDI_REORDER_INVERSE_NUMBERS_AS_L</code></li> |
| * <li><code>#UBIDI_REORDER_INVERSE_LIKE_DIRECT</code></li> |
| * <li><code>#UBIDI_REORDER_INVERSE_FOR_NUMBERS_SPECIAL</code></li> |
| * </ul> |
| * |
| * <p>If this option is set in conjunction with reordering mode |
| * <code>#UBIDI_REORDER_INVERSE_NUMBERS_AS_L</code> or with calling |
| * <code>ubidi_setInverse(TRUE)</code>, it implies |
| * option <code>#UBIDI_INSERT_LRM_FOR_NUMERIC</code> |
| * in calls to function <code>ubidi_writeReordered()</code>.</p> |
| * |
| * <p>For other reordering modes, a minimum number of LRM or RLM characters |
| * will be added to the source text after reordering it so as to ensure |
| * round trip, i.e. when applying the inverse reordering mode on the |
| * resulting logical text with removal of Bidi marks |
| * (option <code>#UBIDI_OPTION_REMOVE_CONTROLS</code> set before calling |
| * <code>ubidi_setPara()</code> or option <code>#UBIDI_REMOVE_BIDI_CONTROLS</code> |
| * in <code>ubidi_writeReordered</code>), the result will be identical to the |
| * source text in the first transformation. |
| * |
| * <p>This option will be ignored if specified together with option |
| * <code>#UBIDI_OPTION_REMOVE_CONTROLS</code>. It inhibits option |
| * <code>UBIDI_REMOVE_BIDI_CONTROLS</code> in calls to function |
| * <code>ubidi_writeReordered()</code> and it implies option |
| * <code>#UBIDI_INSERT_LRM_FOR_NUMERIC</code> in calls to function |
| * <code>ubidi_writeReordered()</code> if the reordering mode is |
| * <code>#UBIDI_REORDER_INVERSE_NUMBERS_AS_L</code>.</p> |
| * |
| * @see ubidi_setReorderingMode |
| * @see ubidi_setReorderingOptions |
| * @stable ICU 3.6 |
| */ |
| UBIDI_OPTION_INSERT_MARKS = 1, |
| |
| /** |
| * option bit for <code>ubidi_setReorderingOptions</code>: |
| * remove Bidi control characters |
| * |
| * <p>This option must be set or reset before calling |
| * <code>ubidi_setPara</code>.</p> |
| * |
| * <p>This option nullifies option <code>#UBIDI_OPTION_INSERT_MARKS</code>. |
| * It inhibits option <code>#UBIDI_INSERT_LRM_FOR_NUMERIC</code> in calls |
| * to function <code>ubidi_writeReordered()</code> and it implies option |
| * <code>#UBIDI_REMOVE_BIDI_CONTROLS</code> in calls to that function.</p> |
| * |
| * @see ubidi_setReorderingMode |
| * @see ubidi_setReorderingOptions |
| * @stable ICU 3.6 |
| */ |
| UBIDI_OPTION_REMOVE_CONTROLS = 2, |
| |
| /** |
| * option bit for <code>ubidi_setReorderingOptions</code>: |
| * process the output as part of a stream to be continued |
| * |
| * <p>This option must be set or reset before calling |
| * <code>ubidi_setPara</code>.</p> |
| * |
| * <p>This option specifies that the caller is interested in processing large |
| * text object in parts. |
| * The results of the successive calls are expected to be concatenated by the |
| * caller. Only the call for the last part will have this option bit off.</p> |
| * |
| * <p>When this option bit is on, <code>ubidi_setPara()</code> may process |
| * less than the full source text in order to truncate the text at a meaningful |
| * boundary. The caller should call <code>ubidi_getProcessedLength()</code> |
| * immediately after calling <code>ubidi_setPara()</code> in order to |
| * determine how much of the source text has been processed. |
| * Source text beyond that length should be resubmitted in following calls to |
| * <code>ubidi_setPara</code>. The processed length may be less than |
| * the length of the source text if a character preceding the last character of |
| * the source text constitutes a reasonable boundary (like a block separator) |
| * for text to be continued.<br> |
| * If the last character of the source text constitutes a reasonable |
| * boundary, the whole text will be processed at once.<br> |
| * If nowhere in the source text there exists |
| * such a reasonable boundary, the processed length will be zero.<br> |
| * The caller should check for such an occurrence and do one of the following: |
| * <ul><li>submit a larger amount of text with a better chance to include |
| * a reasonable boundary.</li> |
| * <li>resubmit the same text after turning off option |
| * <code>UBIDI_OPTION_STREAMING</code>.</li></ul> |
| * In all cases, this option should be turned off before processing the last |
| * part of the text.</p> |
| * |
| * <p>When the <code>UBIDI_OPTION_STREAMING</code> option is used, |
| * it is recommended to call <code>ubidi_orderParagraphsLTR()</code> with |
| * argument <code>orderParagraphsLTR</code> set to <code>TRUE</code> before |
| * calling <code>ubidi_setPara</code> so that later paragraphs may be |
| * concatenated to previous paragraphs on the right.</p> |
| * |
| * @see ubidi_setReorderingMode |
| * @see ubidi_setReorderingOptions |
| * @see ubidi_getProcessedLength |
| * @see ubidi_orderParagraphsLTR |
| * @stable ICU 3.6 |
| */ |
| UBIDI_OPTION_STREAMING = 4 |
| } UBiDiReorderingOption; |
| |
| /** |
| * Specify which of the reordering options |
| * should be applied during Bidi transformations. |
| * |
| * @param pBiDi is a <code>UBiDi</code> object. |
| * @param reorderingOptions is a combination of zero or more of the following |
| * options: |
| * <code>#UBIDI_OPTION_DEFAULT</code>, <code>#UBIDI_OPTION_INSERT_MARKS</code>, |
| * <code>#UBIDI_OPTION_REMOVE_CONTROLS</code>, <code>#UBIDI_OPTION_STREAMING</code>. |
| * |
| * @see ubidi_getReorderingOptions |
| * @stable ICU 3.6 |
| */ |
| U_STABLE void U_EXPORT2 |
| ubidi_setReorderingOptions(UBiDi *pBiDi, uint32_t reorderingOptions); |
| |
| /** |
| * What are the reordering options applied to a given Bidi object? |
| * |
| * @param pBiDi is a <code>UBiDi</code> object. |
| * @return the current reordering options of the Bidi object |
| * @see ubidi_setReorderingOptions |
| * @stable ICU 3.6 |
| */ |
| U_STABLE uint32_t U_EXPORT2 |
| ubidi_getReorderingOptions(UBiDi *pBiDi); |
| |
| /** |
| * Set the context before a call to ubidi_setPara().<p> |
| * |
| * ubidi_setPara() computes the left-right directionality for a given piece |
| * of text which is supplied as one of its arguments. Sometimes this piece |
| * of text (the "main text") should be considered in context, because text |
| * appearing before ("prologue") and/or after ("epilogue") the main text |
| * may affect the result of this computation.<p> |
| * |
| * This function specifies the prologue and/or the epilogue for the next |
| * call to ubidi_setPara(). The characters specified as prologue and |
| * epilogue should not be modified by the calling program until the call |
| * to ubidi_setPara() has returned. If successive calls to ubidi_setPara() |
| * all need specification of a context, ubidi_setContext() must be called |
| * before each call to ubidi_setPara(). In other words, a context is not |
| * "remembered" after the following successful call to ubidi_setPara().<p> |
| * |
| * If a call to ubidi_setPara() specifies UBIDI_DEFAULT_LTR or |
| * UBIDI_DEFAULT_RTL as paraLevel and is preceded by a call to |
| * ubidi_setContext() which specifies a prologue, the paragraph level will |
| * be computed taking in consideration the text in the prologue.<p> |
| * |
| * When ubidi_setPara() is called without a previous call to |
| * ubidi_setContext, the main text is handled as if preceded and followed |
| * by strong directional characters at the current paragraph level. |
| * Calling ubidi_setContext() with specification of a prologue will change |
| * this behavior by handling the main text as if preceded by the last |
| * strong character appearing in the prologue, if any. |
| * Calling ubidi_setContext() with specification of an epilogue will change |
| * the behavior of ubidi_setPara() by handling the main text as if followed |
| * by the first strong character or digit appearing in the epilogue, if any.<p> |
| * |
| * Note 1: if <code>ubidi_setContext</code> is called repeatedly without |
| * calling <code>ubidi_setPara</code>, the earlier calls have no effect, |
| * only the last call will be remembered for the next call to |
| * <code>ubidi_setPara</code>.<p> |
| * |
| * Note 2: calling <code>ubidi_setContext(pBiDi, NULL, 0, NULL, 0, &errorCode)</code> |
| * cancels any previous setting of non-empty prologue or epilogue. |
| * The next call to <code>ubidi_setPara()</code> will process no |
| * prologue or epilogue.<p> |
| * |
| * Note 3: users must be aware that even after setting the context |
| * before a call to ubidi_setPara() to perform e.g. a logical to visual |
| * transformation, the resulting string may not be identical to what it |
| * would have been if all the text, including prologue and epilogue, had |
| * been processed together.<br> |
| * Example (upper case letters represent RTL characters):<br> |
| * prologue = "<code>abc DE</code>"<br> |
| * epilogue = none<br> |
| * main text = "<code>FGH xyz</code>"<br> |
| * paraLevel = UBIDI_LTR<br> |
| * display without prologue = "<code>HGF xyz</code>" |
| * ("HGF" is adjacent to "xyz")<br> |
| * display with prologue = "<code>abc HGFED xyz</code>" |
| * ("HGF" is not adjacent to "xyz")<br> |
| * |
| * @param pBiDi is a paragraph <code>UBiDi</code> object. |
| * |
| * @param prologue is a pointer to the text which precedes the text that |
| * will be specified in a coming call to ubidi_setPara(). |
| * If there is no prologue to consider, then <code>proLength</code> |
| * must be zero and this pointer can be NULL. |
| * |
| * @param proLength is the length of the prologue; if <code>proLength==-1</code> |
| * then the prologue must be zero-terminated. |
| * Otherwise proLength must be >= 0. If <code>proLength==0</code>, it means |
| * that there is no prologue to consider. |
| * |
| * @param epilogue is a pointer to the text which follows the text that |
| * will be specified in a coming call to ubidi_setPara(). |
| * If there is no epilogue to consider, then <code>epiLength</code> |
| * must be zero and this pointer can be NULL. |
| * |
| * @param epiLength is the length of the epilogue; if <code>epiLength==-1</code> |
| * then the epilogue must be zero-terminated. |
| * Otherwise epiLength must be >= 0. If <code>epiLength==0</code>, it means |
| * that there is no epilogue to consider. |
| * |
| * @param pErrorCode must be a valid pointer to an error code value. |
| * |
| * @see ubidi_setPara |
| * @draft ICU 4.8 |
| */ |
| U_DRAFT void U_EXPORT2 |
| ubidi_setContext(UBiDi *pBiDi, |
| const UChar *prologue, int32_t proLength, |
| const UChar *epilogue, int32_t epiLength, |
| UErrorCode *pErrorCode); |
| |
| /** |
| * 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. |
| * This pointer is stored in the UBiDi object and can be retrieved |
| * with <code>ubidi_getText()</code>.<br> |
| * <strong>Note:</strong> the text must be (at least) <code>length</code> long. |
| * |
| * @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.<br><br> |
| * 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>.<br><br> |
| * <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.<br><br> |
| * After the <code>UBiDi</code> object is reused or destroyed, the caller |
| * must take care of the deallocation of the <code>embeddingLevels</code> array.<br><br> |
| * <strong>Note:</strong> the <code>embeddingLevels</code> array must be |
| * at least <code>length</code> long. |
| * 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 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 |
| * @see ubidi_getProcessedLength |
| * @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 value of <code>UBIDI_LTR</code>, <code>UBIDI_RTL</code> |
| * or <code>UBIDI_MIXED</code> |
| * that indicates if the entire text |
| * represented by this object is unidirectional, |
| * and which direction, or if it is mixed-directional. |
| * Note - The value <code>UBIDI_NEUTRAL</code> is never returned from this method. |
| * |
| * @see UBiDiDirection |
| * @stable ICU 2.0 |
| */ |
| U_STABLE UBiDiDirection U_EXPORT2 |
| ubidi_getDirection(const UBiDi *pBiDi); |
| |
| /** |
| * Gets the base direction of the text provided according |
| * to the Unicode Bidirectional Algorithm. The base direction |
| * is derived from the first character in the string with bidirectional |
| * character type L, R, or AL. If the first such character has type L, |
| * <code>UBIDI_LTR</code> is returned. If the first such character has |
| * type R or AL, <code>UBIDI_RTL</code> is returned. If the string does |
| * not contain any character of these types, then |
| * <code>UBIDI_NEUTRAL</code> is returned. |
| * |
| * This is a lightweight function for use when only the base direction |
| * is needed and no further bidi processing of the text is needed. |
| * |
| * @param text is a pointer to the text whose base |
| * direction is needed. |
| * Note: the text must be (at least) @c length long. |
| * |
| * @param length is the length of the text; |
| * if <code>length==-1</code> then the text |
| * must be zero-terminated. |
| * |
| * @return <code>UBIDI_LTR</code>, <code>UBIDI_RTL</code>, |
| * <code>UBIDI_NEUTRAL</code> |
| * |
| * @see UBiDiDirection |
| * @draft ICU 4.6 |
| */ |
| U_DRAFT UBiDiDirection U_EXPORT2 |
| ubidi_getBaseDirection(const UChar *text, int32_t length ); |
| |
| /** |
| * 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.<br> |
| * Note: if the paragraph index is known, it is more efficient to |
| * retrieve the paragraph information using ubidi_getParagraphByIndex().<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_getProcessedLength(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. |
| * |
| * @see ubidi_getProcessedLength |
| * @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. It must be in the range |
| * [0..ubidi_getProcessedLength(pBiDi)]. |
| * |
| * @return The level for the character at charIndex (0 if charIndex is not |
| * in the valid range). |
| * |
| * @see UBiDiLevel |
| * @see ubidi_getProcessedLength |
| * @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 |
| * @see ubidi_getProcessedLength |
| * @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 logicalPosition is a logical position within the source text. |
| * |
| * @param pLogicalLimit will receive the limit of the corresponding run. |
| * The l-value that you point to here may be the |
| * same expression (variable) as the one for |
| * <code>logicalPosition</code>. |
| * This pointer can be <code>NULL</code> if this |
| * value is not necessary. |
| * |
| * @param pLevel will receive the level of the corresponding run. |
| * This pointer can be <code>NULL</code> if this |
| * value is not necessary. |
| * |
| * @see ubidi_getProcessedLength |
| * @stable ICU 2.0 |
| */ |
| U_STABLE void U_EXPORT2 |
| ubidi_getLogicalRun(const UBiDi *pBiDi, int32_t logicalPosition, |
| 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>, |
| * never <code>UBIDI_NEUTRAL</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 |
| * second surrogates before first ones (which is generally a bad idea) |
| * and combining characters before base characters. |
| * <p> |
| * Use of <code>ubidi_writeReordered()</code>, optionally with the |
| * <code>#UBIDI_KEEP_BASE_COMBINING</code> option, can be considered in order |
| * to avoid these issues. |
| * @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> |
| * |
| * The value returned may be <code>#UBIDI_MAP_NOWHERE</code> if there is no |
| * visual position because the corresponding text character is a Bidi control |
| * removed from output by the option <code>#UBIDI_OPTION_REMOVE_CONTROLS</code>. |
| * <p> |
| * When the visual output is altered by using options of |
| * <code>ubidi_writeReordered()</code> such as <code>UBIDI_INSERT_LRM_FOR_NUMERIC</code>, |
| * <code>UBIDI_KEEP_BASE_COMBINING</code>, <code>UBIDI_OUTPUT_REVERSE</code>, |
| * <code>UBIDI_REMOVE_BIDI_CONTROLS</code>, the visual position returned may not |
| * be correct. It is advised to use, when possible, reordering options |
| * such as <code>UBIDI_OPTION_INSERT_MARKS</code> and <code>UBIDI_OPTION_REMOVE_CONTROLS</code>. |
| * <p> |
| * Note that in right-to-left runs, this mapping places |
| * second surrogates before first ones (which is generally a bad idea) |
| * and combining characters before base characters. |
| * Use of <code>ubidi_writeReordered()</code>, optionally with the |
| * <code>#UBIDI_KEEP_BASE_COMBINING</code> option can be considered instead |
| * of using the mapping, in order to avoid these issues. |
| * |
| * @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 |
| * @see ubidi_getProcessedLength |
| * @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> |
| * |
| * The value returned may be <code>#UBIDI_MAP_NOWHERE</code> if there is no |
| * logical position because the corresponding text character is a Bidi mark |
| * inserted in the output by option <code>#UBIDI_OPTION_INSERT_MARKS</code>. |
| * <p> |
| * This is the inverse function to <code>ubidi_getVisualIndex()</code>. |
| * <p> |
| * When the visual output is altered by using options of |
| * <code>ubidi_writeReordered()</code> such as <code>UBIDI_INSERT_LRM_FOR_NUMERIC</code>, |
| * <code>UBIDI_KEEP_BASE_COMBINING</code>, <code>UBIDI_OUTPUT_REVERSE</code>, |
| * <code>UBIDI_REMOVE_BIDI_CONTROLS</code>, the logical position returned may not |
| * be correct. It is advised to use, when possible, reordering options |
| * such as <code>UBIDI_OPTION_INSERT_MARKS</code> and <code>UBIDI_OPTION_REMOVE_CONTROLS</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 |
| * @see ubidi_getResultLength |
| * @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. |
| * <p> |
| * Some values in the map may be <code>#UBIDI_MAP_NOWHERE</code> if the |
| * corresponding text characters are Bidi controls removed from the visual |
| * output by the option <code>#UBIDI_OPTION_REMOVE_CONTROLS</code>. |
| * <p> |
| * When the visual output is altered by using options of |
| * <code>ubidi_writeReordered()</code> such as <code>UBIDI_INSERT_LRM_FOR_NUMERIC</code>, |
| * <code>UBIDI_KEEP_BASE_COMBINING</code>, <code>UBIDI_OUTPUT_REVERSE</code>, |
| * <code>UBIDI_REMOVE_BIDI_CONTROLS</code>, the visual positions returned may not |
| * be correct. It is advised to use, when possible, reordering options |
| * such as <code>UBIDI_OPTION_INSERT_MARKS</code> and <code>UBIDI_OPTION_REMOVE_CONTROLS</code>. |
| * <p> |
| * Note that in right-to-left runs, this mapping places |
| * second surrogates before first ones (which is generally a bad idea) |
| * and combining characters before base characters. |
| * Use of <code>ubidi_writeReordered()</code>, optionally with the |
| * <code>#UBIDI_KEEP_BASE_COMBINING</code> option can be considered instead |
| * of using the mapping, in order to avoid these issues. |
| * |
| * @param pBiDi is the paragraph or line <code>UBiDi</code> object. |
| * |
| * @param indexMap is a pointer to an array of <code>ubidi_getProcessedLength()</code> |
| * indexes which will reflect the reordering of the characters. |
| * If option <code>#UBIDI_OPTION_INSERT_MARKS</code> is set, the number |
| * of elements allocated in <code>indexMap</code> must be no less than |
| * <code>ubidi_getResultLength()</code>. |
| * The array does not need to be initialized.<br><br> |
| * The index map will result in <code>indexMap[logicalIndex]==visualIndex</code>. |
| * |
| * @param pErrorCode must be a valid pointer to an error code value. |
| * |
| * @see ubidi_getVisualMap |
| * @see ubidi_getVisualIndex |
| * @see ubidi_getProcessedLength |
| * @see ubidi_getResultLength |
| * @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. |
| * <p> |
| * Some values in the map may be <code>#UBIDI_MAP_NOWHERE</code> if the |
| * corresponding text characters are Bidi marks inserted in the visual output |
| * by the option <code>#UBIDI_OPTION_INSERT_MARKS</code>. |
| * <p> |
| * When the visual output is altered by using options of |
| * <code>ubidi_writeReordered()</code> such as <code>UBIDI_INSERT_LRM_FOR_NUMERIC</code>, |
| * <code>UBIDI_KEEP_BASE_COMBINING</code>, <code>UBIDI_OUTPUT_REVERSE</code>, |
| * <code>UBIDI_REMOVE_BIDI_CONTROLS</code>, the logical positions returned may not |
| * be correct. It is advised to use, when possible, reordering options |
| * such as <code>UBIDI_OPTION_INSERT_MARKS</code> and <code>UBIDI_OPTION_REMOVE_CONTROLS</code>. |
| * |
| * @param pBiDi is the paragraph or line <code>UBiDi</code> object. |
| * |
| * @param indexMap is a pointer to an array of <code>ubidi_getResultLength()</code> |
| * indexes which will reflect the reordering of the characters. |
| * If option <code>#UBIDI_OPTION_REMOVE_CONTROLS</code> is set, the number |
| * of elements allocated in <code>indexMap</code> must be no less than |
| * <code>ubidi_getProcessedLength()</code>. |
| * The array does not need to be initialized.<br><br> |
| * The index map will result in <code>indexMap[visualIndex]==logicalIndex</code>. |
| * |
| * @param pErrorCode must be a valid pointer to an error code value. |
| * |
| * @see ubidi_getLogicalMap |
| * @see ubidi_getLogicalIndex |
| * @see ubidi_getProcessedLength |
| * @see ubidi_getResultLength |
| * @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 index mapping of the first map is inverted and written to |
| * the second one. |
| * |
| * @param srcMap is an array with <code>length</code> elements |
| * which defines the original mapping from a source array containing |
| * <code>length</code> elements to a destination array. |
| * Some elements of the source array may have no mapping in the |
| * destination array. In that case, their value will be |
| * the special value <code>UBIDI_MAP_NOWHERE</code>. |
| * All elements must be >=0 or equal to <code>UBIDI_MAP_NOWHERE</code>. |
| * Some elements may have a value >= <code>length</code>, if the |
| * destination array has more elements than the source array. |
| * There must be no duplicate indexes (two or more elements with the |
| * same value except <code>UBIDI_MAP_NOWHERE</code>). |
| * |
| * @param destMap is an array with a number of elements equal to 1 + the highest |
| * value in <code>srcMap</code>. |
| * <code>destMap</code> will be filled with the inverse mapping. |
| * If element with index i in <code>srcMap</code> has a value k different |
| * from <code>UBIDI_MAP_NOWHERE</code>, this means that element i of |
| * the source array maps to element k in the destination array. |
| * The inverse map will have value i in its k-th element. |
| * For all elements of the destination array which do not map to |
| * an element in the source array, the corresponding element in the |
| * inverse map will have a value equal to <code>UBIDI_MAP_NOWHERE</code>. |
| * |
| * @param length is the length of each array. |
| * @see UBIDI_MAP_NOWHERE |
| * @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 |
| * |
| * <p>This option does not imply corresponding adjustment of the index |
| * mappings.</p> |
| * |
| * @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) |
| * |
| * <p>This option does not imply corresponding adjustment of the index |
| * mappings.</p> |
| * |
| * @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 |
| |
| /** |
| * Get the length of the source text processed by the last call to |
| * <code>ubidi_setPara()</code>. This length may be different from the length |
| * of the source text if option <code>#UBIDI_OPTION_STREAMING</code> |
| * has been set. |
| * <br> |
| * Note that whenever the length of the text affects the execution or the |
| * result of a function, it is the processed length which must be considered, |
| * except for <code>ubidi_setPara</code> (which receives unprocessed source |
| * text) and <code>ubidi_getLength</code> (which returns the original length |
| * of the source text).<br> |
| * In particular, the processed length is the one to consider in the following |
| * cases: |
| * <ul> |
| * <li>maximum value of the <code>limit</code> argument of |
| * <code>ubidi_setLine</code></li> |
| * <li>maximum value of the <code>charIndex</code> argument of |
| * <code>ubidi_getParagraph</code></li> |
| * <li>maximum value of the <code>charIndex</code> argument of |
| * <code>ubidi_getLevelAt</code></li> |
| * <li>number of elements in the array returned by <code>ubidi_getLevels</code></li> |
| * <li>maximum value of the <code>logicalStart</code> argument of |
| * <code>ubidi_getLogicalRun</code></li> |
| * <li>maximum value of the <code>logicalIndex</code> argument of |
| * <code>ubidi_getVisualIndex</code></li> |
| * <li>number of elements filled in the <code>*indexMap</code> argument of |
| * <code>ubidi_getLogicalMap</code></li> |
| * <li>length of text processed by <code>ubidi_writeReordered</code></li> |
| * </ul> |
| * |
| * @param pBiDi is the paragraph <code>UBiDi</code> object. |
| * |
| * @return The length of the part of the source text processed by |
| * the last call to <code>ubidi_setPara</code>. |
| * @see ubidi_setPara |
| * @see UBIDI_OPTION_STREAMING |
| * @stable ICU 3.6 |
| */ |
| U_STABLE int32_t U_EXPORT2 |
| ubidi_getProcessedLength(const UBiDi *pBiDi); |
| |
| /** |
| * Get the length of the reordered text resulting from the last call to |
| * <code>ubidi_setPara()</code>. This length may be different from the length |
| * of the source text if option <code>#UBIDI_OPTION_INSERT_MARKS</code> |
| * or option <code>#UBIDI_OPTION_REMOVE_CONTROLS</code> has been set. |
| * <br> |
| * This resulting length is the one to consider in the following cases: |
| * <ul> |
| * <li>maximum value of the <code>visualIndex</code> argument of |
| * <code>ubidi_getLogicalIndex</code></li> |
| * <li>number of elements of the <code>*indexMap</code> argument of |
| * <code>ubidi_getVisualMap</code></li> |
| * </ul> |
| * Note that this length stays identical to the source text length if |
| * Bidi marks are inserted or removed using option bits of |
| * <code>ubidi_writeReordered</code>, or if option |
| * <code>#UBIDI_REORDER_INVERSE_NUMBERS_AS_L</code> has been set. |
| * |
| * @param pBiDi is the paragraph <code>UBiDi</code> object. |
| * |
| * @return The length of the reordered text resulting from |
| * the last call to <code>ubidi_setPara</code>. |
| * @see ubidi_setPara |
| * @see UBIDI_OPTION_INSERT_MARKS |
| * @see UBIDI_OPTION_REMOVE_CONTROLS |
| * @stable ICU 3.6 |
| */ |
| U_STABLE int32_t U_EXPORT2 |
| ubidi_getResultLength(const UBiDi *pBiDi); |
| |
| U_CDECL_BEGIN |
| /** |
| * value returned by <code>UBiDiClassCallback</code> callbacks when |
| * there is no need to override the standard Bidi class for a given code point. |
| * @see UBiDiClassCallback |
| * @stable ICU 3.6 |
| */ |
| #define U_BIDI_CLASS_DEFAULT U_CHAR_DIRECTION_COUNT |
| |
| /** |
| * Callback type declaration for overriding default Bidi class values with |
| * custom ones. |
| * <p>Usually, the function pointer will be propagated to a <code>UBiDi</code> |
| * object by calling the <code>ubidi_setClassCallback()</code> function; |
| * then the callback will be invoked by the UBA implementation any time the |
| * class of a character is to be determined.</p> |
| * |
| * @param context is a pointer to the callback private data. |
| * |
| * @param c is the code point to get a Bidi class for. |
| * |
| * @return The directional property / Bidi class for the given code point |
| * <code>c</code> if the default class has been overridden, or |
| * <code>#U_BIDI_CLASS_DEFAULT</code> if the standard Bidi class value |
| * for <code>c</code> is to be used. |
| * @see ubidi_setClassCallback |
| * @see ubidi_getClassCallback |
| * @stable ICU 3.6 |
| */ |
| typedef UCharDirection U_CALLCONV |
| UBiDiClassCallback(const void *context, UChar32 c); |
| |
| U_CDECL_END |
| |
| /** |
| * Retrieve the Bidi class for a given code point. |
| * <p>If a <code>#UBiDiClassCallback</code> callback is defined and returns a |
| * value other than <code>#U_BIDI_CLASS_DEFAULT</code>, that value is used; |
| * otherwise the default class determination mechanism is invoked.</p> |
| * |
| * @param pBiDi is the paragraph <code>UBiDi</code> object. |
| * |
| * @param c is the code point whose Bidi class must be retrieved. |
| * |
| * @return The Bidi class for character <code>c</code> based |
| * on the given <code>pBiDi</code> instance. |
| * @see UBiDiClassCallback |
| * @stable ICU 3.6 |
| */ |
| U_STABLE UCharDirection U_EXPORT2 |
| ubidi_getCustomizedClass(UBiDi *pBiDi, UChar32 c); |
| |
| /** |
| * Set the callback function and callback data used by the UBA |
| * implementation for Bidi class determination. |
| * <p>This may be useful for assigning Bidi classes to PUA characters, or |
| * for special application needs. For instance, an application may want to |
| * handle all spaces like L or R characters (according to the base direction) |
| * when creating the visual ordering of logical lines which are part of a report |
| * organized in columns: there should not be interaction between adjacent |
| * cells.<p> |
| * |
| * @param pBiDi is the paragraph <code>UBiDi</code> object. |
| * |
| * @param newFn is the new callback function pointer. |
| * |
| * @param newContext is the new callback context pointer. This can be NULL. |
| * |
| * @param oldFn fillin: Returns the old callback function pointer. This can be |
| * NULL. |
| * |
| * @param oldContext fillin: Returns the old callback's context. This can be |
| * NULL. |
| * |
| * @param pErrorCode must be a valid pointer to an error code value. |
| * |
| * @see ubidi_getClassCallback |
| * @stable ICU 3.6 |
| */ |
| U_STABLE void U_EXPORT2 |
| ubidi_setClassCallback(UBiDi *pBiDi, UBiDiClassCallback *newFn, |
| const void *newContext, UBiDiClassCallback **oldFn, |
| const void **oldContext, UErrorCode *pErrorCode); |
| |
| /** |
| * Get the current callback function used for Bidi class determination. |
| * |
| * @param pBiDi is the paragraph <code>UBiDi</code> object. |
| * |
| * @param fn fillin: Returns the callback function pointer. |
| * |
| * @param context fillin: Returns the callback's private context. |
| * |
| * @see ubidi_setClassCallback |
| * @stable ICU 3.6 |
| */ |
| U_STABLE void U_EXPORT2 |
| ubidi_getClassCallback(UBiDi *pBiDi, UBiDiClassCallback **fn, const void **context); |
| |
| /** |
| * 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) combining characters. |
| * 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. |
| * |
| * @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.<br><br> |
| * 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. |
| * |
| * @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_getProcessedLength(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. |
| * |
| * @see ubidi_getProcessedLength |
| * @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) combining characters. |
| * 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 |