/*
*
* (C) Copyright IBM Corp. 1998-2011 - All Rights Reserved
*
*/
#ifndef __LOENGINE_H
#define __LOENGINE_H
#include "LETypes.h"
#ifndef U_HIDE_INTERNAL_API
/**
* \file
* \brief C API for complex text layout.
* \internal
*
* This is a technology preview. The API may
* change significantly.
*
*/
/**
* The opaque type for a LayoutEngine.
*
* @internal
*/
typedef void le_engine;
/**
* The opaque type for a font instance.
*
* @internal
*/
typedef void le_font;
/**
* This function returns an le_engine capable of laying out text
* in the given font, script and langauge. Note that the LayoutEngine
* returned may be a subclass of LayoutEngine.
*
* @param font - the font of the text
* @param scriptCode - the script of the text
* @param languageCode - the language of the text
* @param typo_flags - flags that control layout features like kerning and ligatures.
* @param success - output parameter set to an error code if the operation fails
*
* @return an le_engine which can layout text in the given font.
*
* @internal
*/
U_INTERNAL le_engine * U_EXPORT2
le_create(const le_font *font,
le_int32 scriptCode,
le_int32 languageCode,
le_int32 typo_flags,
LEErrorCode *success);
/**
* This function closes the given LayoutEngine. After
* it returns, the le_engine is no longer valid.
*
* @param engine - the LayoutEngine to close.
*
* @internal
*/
U_INTERNAL void U_EXPORT2
le_close(le_engine *engine);
/**
* This routine will compute the glyph, character index and position arrays.
*
* @param engine - the LayoutEngine
* @param chars - the input character context
* @param offset - the offset of the first character to process
* @param count - the number of characters to process
* @param max - the number of characters in the input context
* @param rightToLeft - TRUE if the characers are in a right to left directional run
* @param x - the initial X position
* @param y - the initial Y position
* @param success - output parameter set to an error code if the operation fails
*
* @return the number of glyphs in the glyph array
*
* Note: The glyph, character index and position array can be accessed
* using the getter routines below.
*
* Note: If you call this function more than once, you must call the reset()
* function first to free the glyph, character index and position arrays
* allocated by the previous call.
*
* @internal
*/
U_INTERNAL le_int32 U_EXPORT2
le_layoutChars(le_engine *engine,
const LEUnicode chars[],
le_int32 offset,
le_int32 count,
le_int32 max,
le_bool rightToLeft,
float x,
float y,
LEErrorCode *success);
/**
* This function returns the number of glyphs in the glyph array. Note
* that the number of glyphs will be greater than or equal to the number
* of characters used to create the LayoutEngine.
*
* @param engine - the LayoutEngine
* @param success - output parameter set to an error code if the operation fails.
*
* @return the number of glyphs in the glyph array
*
* @internal
*/
U_INTERNAL le_int32 U_EXPORT2
le_getGlyphCount(le_engine *engine,
LEErrorCode *success);
/**
* This function copies the glyph array into a caller supplied array.
* The caller must ensure that the array is large enough to hold all
* the glyphs.
*
* @param engine - the LayoutEngine
* @param glyphs - the destiniation glyph array
* @param success - set to an error code if the operation fails
*
* @internal
*/
U_INTERNAL void U_EXPORT2
le_getGlyphs(le_engine *engine,
LEGlyphID glyphs[],
LEErrorCode *success);
/**
* This function copies the character index array into a caller supplied array.
* The caller must ensure that the array is large enough to hold a
* character index for each glyph.
*
* @param engine - the LayoutEngine
* @param charIndices - the destiniation character index array
* @param success - set to an error code if the operation fails
*
* @internal
*/
U_INTERNAL void U_EXPORT2
le_getCharIndices(le_engine *engine,
le_int32 charIndices[],
LEErrorCode *success);
/**
* This function copies the character index array into a caller supplied array.
* The caller must ensure that the array is large enough to hold a
* character index for each glyph.
*
* @param engine - the LayoutEngine
* @param charIndices - the destiniation character index array
* @param indexBase - an offset that will be added to each index.
* @param success - set to an error code if the operation fails
*
* @internal
*/
U_INTERNAL void U_EXPORT2
le_getCharIndicesWithBase(le_engine *engine,
le_int32 charIndices[],
le_int32 indexBase,
LEErrorCode *success);
/**
* This function copies the position array into a caller supplied array.
* The caller must ensure that the array is large enough to hold an
* X and Y position for each glyph, plus an extra X and Y for the
* advance of the last glyph.
*
* @param engine - the LayoutEngine
* @param positions - the destiniation position array
* @param success - set to an error code if the operation fails
*
* @internal
*/
U_INTERNAL void U_EXPORT2
le_getGlyphPositions(le_engine *engine,
float positions[],
LEErrorCode *success);
/**
* This function returns the X and Y position of the glyph at
* the given index.
*
* Input parameters:
* @param engine - the LayoutEngine
* @param glyphIndex - the index of the glyph
*
* Output parameters:
* @param x - the glyph's X position
* @param y - the glyph's Y position
* @param success - set to an error code if the operation fails
*
* @internal
*/
U_INTERNAL void U_EXPORT2
le_getGlyphPosition(le_engine *engine,
le_int32 glyphIndex,
float *x,
float *y,
LEErrorCode *success);
/**
* This function frees the glyph, character index and position arrays
* so that the LayoutEngine can be reused to layout a different
* characer array. (This function is also called by le_close)
*
* @param engine - the LayoutEngine
* @param success - set to an error code if the operation fails
*
* @internal
*/
U_INTERNAL void U_EXPORT2
le_reset(le_engine *engine,
LEErrorCode *success);
#endif /* U_HIDE_INTERNAL_API */
#endif