path: root/Build/source/texk/web2c/xetexdir/XeTeXOTLayoutEngine.cpp

/****************************************************************************\
 Part of the XeTeX typesetting system
 copyright (c) 1994-2008 by SIL International
 copyright (c) 2009 by Jonathan Kew

 Written by Jonathan Kew

Permission is hereby granted, free of charge, to any person obtaining
a copy of this software and associated documentation files (the
"Software"), to deal in the Software without restriction, including
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permit persons to whom the Software is furnished to do so, subject to
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The above copyright notice and this permission notice shall be
included in all copies or substantial portions of the Software.

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WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

Except as contained in this notice, the name of the copyright holders
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\****************************************************************************/

#include "XeTeXOTLayoutEngine.h"

/****************************************************************************\
class XeTeXHanLayoutEngine
  moved from XeTeXOTLayoutEngine.h to here in order not to include it into
  XeTeXLayoutInterface.cpp.
\****************************************************************************/
class XeTeXHanLayoutEngine : public XeTeXOTLayoutEngine
{
public:
    XeTeXHanLayoutEngine(const XeTeXFontInst *fontInstance, LETag scriptTag, LETag languageTag,
                            const GlyphSubstitutionTableHeader *gsubTable,
                            const GlyphPositioningTableHeader* gposTable,
							const LETag* addFeatures, const le_int32* addParams,
							const LETag* removeFeatures
#if U_ICU_VERSION_CODE >= 42
				, LEErrorCode &success
#endif
			);

    virtual ~XeTeXHanLayoutEngine();

    virtual UClassID getDynamicClassID() const;
    static UClassID getStaticClassID();
};

#include "layout/ArabicLayoutEngine.h"
#include "layout/IndicLayoutEngine.h"
#include "layout/TibetanLayoutEngine.h"
#include "layout/ThaiLayoutEngine.h"
#include "layout/KhmerLayoutEngine.h"

#include "layout/LEScripts.h"
#include "layout/LELanguages.h"

const LETag emptyTag = 0x00000000;

static le_int32 getScriptCode(LETag scriptTag)
{
	for (le_int32 i = 0; i < scriptCodeCount; ++i)
		if (OpenTypeLayoutEngine::getScriptTag(i) == scriptTag)
			return i;
	return -1;
}

static le_int32 getLanguageCode(LETag languageTag)
{
	for (le_int32 i = 0; i < languageCodeCount; ++i)
		if (OpenTypeLayoutEngine::getLangSysTag(i) == languageTag)
			return i;
	return -1;
}

/*
 * XeTeXOTLayoutEngine
 */

UOBJECT_DEFINE_RTTI_IMPLEMENTATION(XeTeXOTLayoutEngine)

LayoutEngine* XeTeXOTLayoutEngine::LayoutEngineFactory
				(const XeTeXFontInst* fontInstance,
					LETag scriptTag, LETag languageTag,
					const LETag* addFeatures, const le_int32* addParams,
					const LETag* removeFeatures,
					LEErrorCode &success)
{
    static le_uint32 gsubTableTag = LE_GSUB_TABLE_TAG;
    static le_uint32 gposTableTag = LE_GPOS_TABLE_TAG;

    if (LE_FAILURE(success))
        return NULL;

    const GlyphSubstitutionTableHeader* gsubTable = (const GlyphSubstitutionTableHeader*)fontInstance->getFontTable(gsubTableTag);
    const GlyphPositioningTableHeader* gposTable = (const GlyphPositioningTableHeader*)fontInstance->getFontTable(gposTableTag);
    LayoutEngine *result = NULL;
	
	le_uint32   scriptCode = getScriptCode(scriptTag);
	le_uint32   languageCode = getLanguageCode(languageTag);

	le_int32	typoFlags = 3;

    if ((gsubTable != NULL && gsubTable->coversScript(scriptTag))
    	|| (gposTable != NULL && gposTable->coversScript(scriptTag))) {
        switch (scriptCode) {
        case bengScriptCode:
        case devaScriptCode:
        case gujrScriptCode:
        case kndaScriptCode:
        case mlymScriptCode:
        case oryaScriptCode:
        case guruScriptCode:
        case tamlScriptCode:
        case teluScriptCode:
        case sinhScriptCode:
//            result = new XeTeXIndicLayoutEngine(fontInstance, scriptTag, languageTag, gsubTable, addFeatures, removeFeatures);
            result = new IndicOpenTypeLayoutEngine(fontInstance, scriptCode, languageCode, typoFlags,
#if U_ICU_VERSION_CODE >= 42
                                                   FALSE,
#endif
                                                   gsubTable XeTeX_success);
            break;

        case arabScriptCode:
        case syrcScriptCode:
        case mongScriptCode:
//            result = new XeTeXArabicLayoutEngine(fontInstance, scriptTag, languageTag, gsubTable, addFeatures, removeFeatures);
            result = new ArabicOpenTypeLayoutEngine(fontInstance, scriptCode, languageCode, typoFlags, gsubTable XeTeX_success);
            break;

        case bopoScriptCode:
        case haniScriptCode:
        case hangScriptCode:
        case hiraScriptCode:
        case kanaScriptCode:
        case hrktScriptCode:
            result = new XeTeXHanLayoutEngine(fontInstance, scriptTag, languageTag, gsubTable, gposTable, addFeatures, addParams, removeFeatures XeTeX_success);
            break;

        case tibtScriptCode:
            result = new TibetanOpenTypeLayoutEngine(fontInstance, scriptCode, languageCode, typoFlags, gsubTable XeTeX_success);
            break;

        case khmrScriptCode:
            result = new KhmerOpenTypeLayoutEngine(fontInstance, scriptCode, languageCode, typoFlags, gsubTable XeTeX_success);
            break;

        default:
            result = new XeTeXOTLayoutEngine(fontInstance, scriptTag, languageTag, gsubTable, gposTable, addFeatures, addParams, removeFeatures XeTeX_success);
            break;
        }
    }
	else {
		switch (scriptCode) {
		case bengScriptCode:
		case devaScriptCode:
		case gujrScriptCode:
		case kndaScriptCode:
		case mlymScriptCode:
		case oryaScriptCode:
		case guruScriptCode:
		case tamlScriptCode:
		case teluScriptCode:
		case sinhScriptCode:
			result = new IndicOpenTypeLayoutEngine(fontInstance, scriptCode, languageCode, typoFlags XeTeX_success);
			break;

		case arabScriptCode:
//		case hebrScriptCode:
			result = new UnicodeArabicOpenTypeLayoutEngine(fontInstance, scriptCode, languageCode, typoFlags XeTeX_success);
			break;

		case thaiScriptCode:
			result = new ThaiLayoutEngine(fontInstance, scriptCode, languageCode, typoFlags XeTeX_success);
			break;

		default:
			result = new OpenTypeLayoutEngine(fontInstance, scriptCode, languageCode, typoFlags XeTeX_success);
			break;
		}
    }

#if U_ICU_VERSION_CODE >= 42
    if (LE_FAILURE(success))
        return NULL;
#else
    if (result == NULL)
        success = LE_MEMORY_ALLOCATION_ERROR;
#endif

    return result;
}

XeTeXOTLayoutEngine::XeTeXOTLayoutEngine(
	const LEFontInstance* fontInstance, LETag scriptTag, LETag languageTag,
	const GlyphSubstitutionTableHeader* gsubTable, const GlyphPositioningTableHeader* gposTable,
	const LETag* addFeatures, const le_int32* addParams, const LETag* removeFeatures
#if U_ICU_VERSION_CODE >= 42
				, LEErrorCode &success
#endif
			)
		: OpenTypeLayoutEngine(fontInstance, getScriptCode(scriptTag), getLanguageCode(languageTag), 3, gsubTable XeTeX_success)
{
	fDefaultFeatureMap = fFeatureMap;
	
	// check the result of setScriptAndLanguageTags(), in case they were unknown to ICU
	if (fScriptTag != scriptTag || fLangSysTag != languageTag) {
		fScriptTag = scriptTag;
		fLangSysTag = languageTag;
	
		// reset the GPOS if the tags changed
		fGPOSTable = NULL;
		if (gposTable != NULL && gposTable->coversScriptAndLanguage(fScriptTag, fLangSysTag)) {
			fGPOSTable = gposTable;
		}
	}

	adjustFeatures(addFeatures, addParams, removeFeatures);
}

XeTeXOTLayoutEngine::~XeTeXOTLayoutEngine()
{
	if (fFeatureMap != NULL && fFeatureMap != fDefaultFeatureMap)
		LE_DELETE_ARRAY(fFeatureMap);
	if (fFeatureParamList != NULL)
		LE_DELETE_ARRAY(fFeatureParamList);
}

void XeTeXOTLayoutEngine::adjustFeatures(const LETag* addTags, const le_int32* addParams, const LETag* removeTags)
{
	// bail out if nothing was requested!
	if ((addTags == NULL || *addTags == emptyTag) && (removeTags == NULL || *removeTags == emptyTag))
		return;

	// figure out total tag count: initial set - removed tags + added tags omitting duplicates
	le_int32	totalCount = 0;
	for (le_int32 i = 0; i < fFeatureMapCount; ++i) {
		// skip any that are disabled by the mask
		if ((fFeatureMask & fFeatureMap[i].mask) != 0) {
			bool	remove = false;
			for (const LETag* r = removeTags; r != NULL && *r != emptyTag; ++r)
				if (*r == fFeatureMap[i].tag) {
					remove = true;
					break;
				}
			if (!remove)
				++totalCount;
		}
	}
	for (const LETag* a = addTags; a != NULL && *a != emptyTag; ++a) {
		// before counting an add tag, check original map, and check for duplicates in list
		bool	add = true;
		for (le_int32 i = 0; i < fFeatureMapCount; ++i)
			if (*a == fFeatureMap[i].tag) {
				if ((fFeatureMask & fFeatureMap[i].mask) != 0)
					add = false;
				break;
			}
		if (add) {
			for (const LETag* t = addTags; t != a; ++t)
				if (*a == *t) {
					add = false;
					break;
				}
		}
		if (add)
			++totalCount;
	}
	
	if (totalCount > 32)
		fprintf(stderr, "\n*** feature count exceeds mask size; some features will be ignored\n");

	// allocate new map
	FeatureMap* newFeatureMap = LE_NEW_ARRAY(FeatureMap, totalCount);
	le_int32	newFeatureCount = 0;
	le_int32*	newParamList = (addParams == NULL) ? NULL : LE_NEW_ARRAY(le_int32, totalCount);
	
	// copy the features into the map and assign mask bits
	FeatureMask	newFeatureMask = 0;
	FeatureMask	maskBit = 0x80000000UL;
	for (le_int32 i = 0; i < fFeatureMapCount; ++i) {
		bool	remove = false;
		if ((fFeatureMask & fFeatureMap[i].mask) == 0)
			remove = true;
		else
			for (const LETag* r = removeTags; r != NULL && *r != emptyTag; ++r)
				if (*r == fFeatureMap[i].tag) {
					remove = true;
					break;
				}
		if (!remove) {
			newFeatureMap[newFeatureCount].tag = fFeatureMap[i].tag;
			newFeatureMap[newFeatureCount].mask = maskBit;
			if (newParamList != NULL)
				newParamList[newFeatureCount] = 0;
			++newFeatureCount;
			newFeatureMask |= maskBit;
			maskBit >>= 1;
		}
	}
	const le_int32* param = addParams;
	for (const LETag* a = addTags; a != NULL && *a != emptyTag; ++a) {
		bool	add = true;
		for (le_int32 i = 0; i < fFeatureMapCount; ++i)
			if (*a == fFeatureMap[i].tag) {
				if ((fFeatureMask & fFeatureMap[i].mask) != 0)
					add = false;
				break;
			}
		if (add) {
			for (const LETag* t = addTags; t != a; ++t)
				if (*a == *t) {
					add = false;
					break;
				}
		}
		if (add) {
			newFeatureMap[newFeatureCount].tag = *a;
			newFeatureMap[newFeatureCount].mask = maskBit;
			if (newParamList != NULL)
				newParamList[newFeatureCount] = *param++;
			++newFeatureCount;
			newFeatureMask |= maskBit;
			maskBit >>= 1;
		}
	}

	fFeatureMask = newFeatureMask;
	fFeatureMap = newFeatureMap;
	fFeatureMapCount = newFeatureCount;
	fFeatureParamList = newParamList;
}


/*
 * XeTeXHanLayoutEngine
 */

UOBJECT_DEFINE_RTTI_IMPLEMENTATION(XeTeXHanLayoutEngine)

static const LETag loclFeatureTag = LE_LOCL_FEATURE_TAG;
static const LETag smplFeatureTag = LE_SMPL_FEATURE_TAG;
static const LETag tradFeatureTag = LE_TRAD_FEATURE_TAG;
static const LETag vertFeatureTag = LE_VERT_FEATURE_TAG;
static const LETag vrt2FeatureTag = LE_VRT2_FEATURE_TAG;

#define loclFeatureMask 0x80000000UL
#define smplFeatureMask 0x40000000UL
#define tradFeatureMask 0x20000000UL
#define vertFeatureMask 0x10000000UL
#define vrt2FeatureMask 0x08000000UL

static const FeatureMap featureMap[] = {
    {loclFeatureTag, loclFeatureMask},
    {smplFeatureTag, smplFeatureMask},
    {tradFeatureTag, tradFeatureMask},
    {vertFeatureTag, vertFeatureMask},
    {vrt2FeatureTag, vrt2FeatureMask},
};
static const le_int32 featureMapCount = LE_ARRAY_SIZE(featureMap);

#define HORIZ_FEATURES (loclFeatureMask)
#define VERT_FEATURES  (loclFeatureMask|vertFeatureMask|vrt2FeatureMask)

XeTeXHanLayoutEngine::XeTeXHanLayoutEngine(const XeTeXFontInst *fontInstance, LETag scriptTag, LETag languageTag,
                            const GlyphSubstitutionTableHeader *gsubTable, const GlyphPositioningTableHeader *gposTable,
							const LETag *addFeatures, const le_int32* addParams,
							const LETag *removeFeatures
#if U_ICU_VERSION_CODE >= 42
				, LEErrorCode &success
#endif
			)
	: XeTeXOTLayoutEngine(fontInstance, scriptTag, languageTag, gsubTable, gposTable, NULL, NULL, NULL XeTeX_success)
{
	// reset the feature map and default features
	fFeatureMap = featureMap;
	fDefaultFeatureMap = fFeatureMap;
	fFeatureMapCount = featureMapCount;

	fFeatureMask = fontInstance->getLayoutDirVertical() ? VERT_FEATURES : HORIZ_FEATURES;
	
	// then apply any adjustments
	adjustFeatures(addFeatures, addParams, removeFeatures);
}

XeTeXHanLayoutEngine::~XeTeXHanLayoutEngine()
{
}