fontservices/textshaperplugin/test/letest/PortableFontInstance.cpp
changeset 0 1fb32624e06b
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/fontservices/textshaperplugin/test/letest/PortableFontInstance.cpp	Tue Feb 02 02:02:46 2010 +0200
@@ -0,0 +1,281 @@
+/*
+ *******************************************************************************
+ *
+ *   Copyright (C) 1999-2003, International Business Machines
+ *   Corporation and others.  All Rights Reserved.
+ *
+ *******************************************************************************
+ *   file name:  PortableFontInstance.cpp
+ *
+ *   created on: 11/22/1999
+ *   created by: Eric R. Mader
+ */
+
+#include <stdio.h>
+
+#include "layout/LETypes.h"
+#include "layout/LEFontInstance.h"
+#include "layout/LESwaps.h"
+
+#include "PortableFontInstance.h"
+
+#include "sfnt.h"
+
+#include <string.h>
+
+//
+// Finds the high bit by binary searching
+// through the bits in n.
+//
+le_int8 PortableFontInstance::highBit(le_int32 value)
+{
+    if (value <= 0) {
+        return -32;
+    }
+
+    le_uint8 bit = 0;
+
+    if (value >= 1 << 16) {
+        value >>= 16;
+        bit += 16;
+    }
+
+    if (value >= 1 << 8) {
+        value >>= 8;
+        bit += 8;
+    }
+
+    if (value >= 1 << 4) {
+        value >>= 4;
+        bit += 4;
+    }
+
+    if (value >= 1 << 2) {
+        value >>= 2;
+        bit += 2;
+    }
+
+    if (value >= 1 << 1) {
+        value >>= 1;
+        bit += 1;
+    }
+
+    return bit;
+}
+
+
+PortableFontInstance::PortableFontInstance(char *fileName, float pointSize, LEErrorCode &status)
+    : fFile(NULL), fUnitsPerEM(0), fPointSize(pointSize), fAscent(0), fDescent(0), fLeading(0),
+      fDirectory(NULL), fCMAPMapper(NULL), fHMTXTable(NULL), fNumGlyphs(0), fNumLongHorMetrics(0)
+{
+    if (LE_FAILURE(status)) {
+        return;
+    }
+
+    // open the font file
+    fFile = fopen(fileName, "rb");
+
+    if (fFile == NULL) {
+        status = LE_FONT_FILE_NOT_FOUND_ERROR;
+        return;
+    }
+
+    // read in the directory
+    SFNTDirectory tempDir;
+
+    fread(&tempDir, sizeof tempDir, 1, fFile);
+
+    le_int32 dirSize = sizeof tempDir + ((SWAPW(tempDir.numTables) - ANY_NUMBER) * sizeof(DirectoryEntry));
+    const LETag headTag = LE_HEAD_TABLE_TAG;
+    const LETag hheaTag = LE_HHEA_TABLE_TAG;
+    const HEADTable *headTable = NULL;
+    const HHEATable *hheaTable = NULL;
+    le_uint16 numTables = 0;
+
+    fDirectory = (const SFNTDirectory *) LE_NEW_ARRAY(char, dirSize);
+
+    if (fDirectory == NULL) {
+        status = LE_MEMORY_ALLOCATION_ERROR;
+        goto error_exit;
+    }
+
+    fseek(fFile, 0L, SEEK_SET);
+    fread((void *) fDirectory, sizeof(char), dirSize, fFile);
+
+    //
+    // We calculate these numbers 'cause some fonts
+    // have bogus values for them in the directory header.
+    //
+    numTables = SWAPW(fDirectory->numTables);
+    fDirPower = 1 << highBit(numTables);
+    fDirExtra = numTables - fDirPower;
+
+    // read unitsPerEm from 'head' table
+    headTable = (const HEADTable *) readFontTable(headTag);
+
+    if (headTable == NULL) {
+        status = LE_MISSING_FONT_TABLE_ERROR;
+        goto error_exit;
+    }
+
+    fUnitsPerEM = SWAPW(headTable->unitsPerEm);
+    deleteTable(headTable);
+
+    hheaTable = (HHEATable *) readFontTable(hheaTag);
+
+    if (hheaTable == NULL) {
+        status = LE_MISSING_FONT_TABLE_ERROR;
+        goto error_exit;
+    }
+
+    fAscent  = (le_int32) yUnitsToPoints((float) SWAPW(hheaTable->ascent));
+    fDescent = (le_int32) yUnitsToPoints((float) SWAPW(hheaTable->descent));
+    fLeading = (le_int32) yUnitsToPoints((float) SWAPW(hheaTable->lineGap));
+
+    fNumLongHorMetrics = SWAPW(hheaTable->numOfLongHorMetrics);
+
+    deleteTable((void *) hheaTable);
+
+    fCMAPMapper = findUnicodeMapper();
+
+    if (fCMAPMapper == NULL) {
+        status = LE_MISSING_FONT_TABLE_ERROR;
+        goto error_exit;
+    }
+
+    return;
+
+error_exit:
+    fclose(fFile);
+    fFile = NULL;
+    return;
+}
+
+PortableFontInstance::~PortableFontInstance()
+{
+    if (fFile != NULL) {
+        fclose(fFile);
+
+        deleteTable(fHMTXTable);
+
+        delete fCMAPMapper;
+
+        LE_DELETE_ARRAY(fDirectory);
+    }
+};
+
+void PortableFontInstance::deleteTable(const void *table) const
+{
+    LE_DELETE_ARRAY(table);
+}
+
+const DirectoryEntry *PortableFontInstance::findTable(LETag tag) const
+{
+    if (fDirectory != NULL) {
+        le_uint16 table = 0;
+        le_uint16 probe = fDirPower;
+
+        if (SWAPL(fDirectory->tableDirectory[fDirExtra].tag) <= tag) {
+            table = fDirExtra;
+        }
+
+        while (probe > (1 << 0)) {
+            probe >>= 1;
+
+            if (SWAPL(fDirectory->tableDirectory[table + probe].tag) <= tag) {
+                table += probe;
+            }
+        }
+
+        if (SWAPL(fDirectory->tableDirectory[table].tag) == tag) {
+            return &fDirectory->tableDirectory[table];
+        }
+    }
+
+    return NULL;
+}
+
+const void *PortableFontInstance::readTable(LETag tag, le_uint32 *length) const
+{
+    const DirectoryEntry *entry = findTable(tag);
+
+    if (entry == NULL) {
+        *length = 0;
+        return NULL;
+    }
+
+    *length = SWAPL(entry->length);
+
+    void *table = LE_NEW_ARRAY(char, *length);
+
+    if (table != NULL) {
+        fseek(fFile, SWAPL(entry->offset), SEEK_SET);
+        fread(table, sizeof(char), *length, fFile);
+    }
+
+    return table;
+}
+
+const void *PortableFontInstance::getFontTable(LETag tableTag) const
+{
+    return FontTableCache::find(tableTag);
+}
+
+const void *PortableFontInstance::readFontTable(LETag tableTag) const
+{
+    le_uint32 len;
+
+    return readTable(tableTag, &len);
+}
+
+CMAPMapper *PortableFontInstance::findUnicodeMapper()
+{
+    LETag cmapTag = LE_CMAP_TABLE_TAG;
+    const CMAPTable *cmap = (CMAPTable *) readFontTable(cmapTag);
+
+    if (cmap == NULL) {
+        return NULL;
+    }
+
+    return CMAPMapper::createUnicodeMapper(cmap);
+}
+
+
+void PortableFontInstance::getGlyphAdvance(LEGlyphID glyph, LEPoint &advance) const
+{
+    TTGlyphID ttGlyph = (TTGlyphID) LE_GET_GLYPH(glyph);
+
+    if (fHMTXTable == NULL) {
+        LETag maxpTag = LE_MAXP_TABLE_TAG;
+        LETag hmtxTag = LE_HMTX_TABLE_TAG;
+        const MAXPTable *maxpTable = (MAXPTable *) readFontTable(maxpTag);
+        PortableFontInstance *realThis = (PortableFontInstance *) this;
+
+        if (maxpTable != NULL) {
+            realThis->fNumGlyphs = SWAPW(maxpTable->numGlyphs);
+            deleteTable(maxpTable);
+        }
+
+        realThis->fHMTXTable = (const HMTXTable *) readFontTable(hmtxTag);
+    }
+
+    le_uint16 index = ttGlyph;
+
+    if (ttGlyph >= fNumGlyphs || fHMTXTable == NULL) {
+        advance.fX = advance.fY = 0;
+        return;
+    }
+
+    if (ttGlyph >= fNumLongHorMetrics) {
+        index = fNumLongHorMetrics - 1;
+    }
+
+    advance.fX = xUnitsToPoints(SWAPW(fHMTXTable->hMetrics[index].advanceWidth));
+    advance.fY = 0;
+}
+
+le_bool PortableFontInstance::getGlyphPoint(LEGlyphID glyph, le_int32 pointNumber, LEPoint &point) const
+{
+    return FALSE;
+}
+