fontservices/textshaperplugin/IcuSource/layout/ThaiLayoutEngine.cpp
changeset 0 1fb32624e06b
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/fontservices/textshaperplugin/IcuSource/layout/ThaiLayoutEngine.cpp	Tue Feb 02 02:02:46 2010 +0200
@@ -0,0 +1,94 @@
+
+/*
+ *
+ * (C) Copyright IBM Corp. 1998-2005 - All Rights Reserved
+ *
+ */
+
+#include "LETypes.h"
+#include "LayoutEngine.h"
+#include "ThaiLayoutEngine.h"
+#include "ScriptAndLanguageTags.h"
+#include "LEGlyphStorage.h"
+
+#include "ThaiShaping.h"
+
+U_NAMESPACE_BEGIN
+
+UOBJECT_DEFINE_RTTI_IMPLEMENTATION(ThaiLayoutEngine)
+
+ThaiLayoutEngine::ThaiLayoutEngine(const LEFontInstance *fontInstance, le_int32 scriptCode, le_int32 languageCode, le_int32 typoFlags)
+    : LayoutEngine(fontInstance, scriptCode, languageCode, typoFlags)
+{
+    fErrorChar = 0x25CC;
+
+    // Figure out which presentation forms the font uses
+    if (fontInstance->canDisplay(0x0E64)) {
+        // WorldType uses reserved space in Thai block
+        fGlyphSet = 0;
+    } else if (fontInstance->canDisplay(0xF701)) {
+        // Microsoft corporate zone
+        fGlyphSet = 1;
+
+        if (!fontInstance->canDisplay(fErrorChar)) {
+            fErrorChar = 0xF71B;
+        }
+    } else if (fontInstance->canDisplay(0xF885)) {
+        // Apple corporate zone
+        fGlyphSet = 2;
+    } else {
+        // no presentation forms in the font
+        fGlyphSet = 3;
+    }
+}
+
+ThaiLayoutEngine::~ThaiLayoutEngine()
+{
+    // nothing to do
+}
+
+// Input: characters (0..max provided for context)
+// Output: glyphs, char indices
+// Returns: the glyph count
+// NOTE: this assumes that ThaiShaping::compose will allocate the outChars array...
+le_int32 ThaiLayoutEngine::computeGlyphs(const LEUnicode chars[], le_int32 offset, le_int32 count, le_int32 max, le_bool /*rightToLeft*/, LEGlyphStorage &glyphStorage, LEErrorCode &success)
+{
+    if (LE_FAILURE(success)) {
+        return 0;
+    }
+
+    if (chars == NULL || offset < 0 || count < 0 || max < 0 || offset >= max || offset + count > max) {
+        success = LE_ILLEGAL_ARGUMENT_ERROR;
+        return 0;
+    }
+
+    LEUnicode *outChars;
+    le_int32 glyphCount;
+    
+    // This is enough room for the worst-case expansion
+    // (it says here...)
+    outChars = LE_NEW_ARRAY(LEUnicode, count * 2);
+
+    if (outChars == NULL) {
+        success = LE_MEMORY_ALLOCATION_ERROR;
+        return 0;
+    }
+
+    glyphStorage.allocateGlyphArray(count * 2, FALSE, success);
+
+    if (LE_FAILURE(success)) {
+        LE_DELETE_ARRAY(outChars);
+        success = LE_MEMORY_ALLOCATION_ERROR;
+        return 0;
+    }
+
+    glyphCount = ThaiShaping::compose(chars, offset, count, fGlyphSet, fErrorChar, outChars, glyphStorage);
+    mapCharsToGlyphs(outChars, 0, glyphCount, FALSE, FALSE, glyphStorage, success);
+
+    LE_DELETE_ARRAY(outChars);
+
+    glyphStorage.adoptGlyphCount(glyphCount);
+    return glyphCount;
+}
+
+U_NAMESPACE_END