1 

     2 /*

     3  *

     4  * (C) Copyright IBM Corp. 1998-2005 - All Rights Reserved

     5  *

     6  */

     7 

     8 #include "LETypes.h"

     9 #include "LayoutEngine.h"

    10 #include "ThaiLayoutEngine.h"

    11 #include "ScriptAndLanguageTags.h"

    12 #include "LEGlyphStorage.h"

    13 

    14 #include "ThaiShaping.h"

    15 

    16 U_NAMESPACE_BEGIN

    17 

    18 UOBJECT_DEFINE_RTTI_IMPLEMENTATION(ThaiLayoutEngine)

    19 

    20 ThaiLayoutEngine::ThaiLayoutEngine(const LEFontInstance *fontInstance, le_int32 scriptCode, le_int32 languageCode, le_int32 typoFlags)

    21     : LayoutEngine(fontInstance, scriptCode, languageCode, typoFlags)

    22 {

    23     fErrorChar = 0x25CC;

    24 

    25     // Figure out which presentation forms the font uses

    26     if (fontInstance->canDisplay(0x0E64)) {

    27         // WorldType uses reserved space in Thai block

    28         fGlyphSet = 0;

    29     } else if (fontInstance->canDisplay(0xF701)) {

    30         // Microsoft corporate zone

    31         fGlyphSet = 1;

    32 

    33         if (!fontInstance->canDisplay(fErrorChar)) {

    34             fErrorChar = 0xF71B;

    35         }

    36     } else if (fontInstance->canDisplay(0xF885)) {

    37         // Apple corporate zone

    38         fGlyphSet = 2;

    39     } else {

    40         // no presentation forms in the font

    41         fGlyphSet = 3;

    42     }

    43 }

    44 

    45 ThaiLayoutEngine::~ThaiLayoutEngine()

    46 {

    47     // nothing to do

    48 }

    49 

    50 // Input: characters (0..max provided for context)

    51 // Output: glyphs, char indices

    52 // Returns: the glyph count

    53 // NOTE: this assumes that ThaiShaping::compose will allocate the outChars array...

    54 le_int32 ThaiLayoutEngine::computeGlyphs(const LEUnicode chars[], le_int32 offset, le_int32 count, le_int32 max, le_bool /*rightToLeft*/, LEGlyphStorage &glyphStorage, LEErrorCode &success)

    55 {

    56     if (LE_FAILURE(success)) {

    57         return 0;

    58     }

    59 

    60     if (chars == NULL || offset < 0 || count < 0 || max < 0 || offset >= max || offset + count > max) {

    61         success = LE_ILLEGAL_ARGUMENT_ERROR;

    62         return 0;

    63     }

    64 

    65     LEUnicode *outChars;

    66     le_int32 glyphCount;

    67     

    68     // This is enough room for the worst-case expansion

    69     // (it says here...)

    70     outChars = LE_NEW_ARRAY(LEUnicode, count * 2);

    71 

    72     if (outChars == NULL) {

    73         success = LE_MEMORY_ALLOCATION_ERROR;

    74         return 0;

    75     }

    76 

    77     glyphStorage.allocateGlyphArray(count * 2, FALSE, success);

    78 

    79     if (LE_FAILURE(success)) {

    80         LE_DELETE_ARRAY(outChars);

    81         success = LE_MEMORY_ALLOCATION_ERROR;

    82         return 0;

    83     }

    84 

    85     glyphCount = ThaiShaping::compose(chars, offset, count, fGlyphSet, fErrorChar, outChars, glyphStorage);

    86     mapCharsToGlyphs(outChars, 0, glyphCount, FALSE, FALSE, glyphStorage, success);

    87 

    88     LE_DELETE_ARRAY(outChars);

    89 

    90     glyphStorage.adoptGlyphCount(glyphCount);

    91     return glyphCount;

    92 }

    93 

    94 U_NAMESPACE_END