CharacterIndex logicalIndex = 0u;
- const Length numberOfGlyphs = visualModel->mGlyphs.Count();
- const Length numberOfLines = visualModel->mLines.Count();
- if( ( 0 == numberOfGlyphs ) ||
- ( 0 == numberOfLines ) )
+ const Length totalNumberOfGlyphs = visualModel->mGlyphs.Count();
+ const Length totalNumberOfLines = visualModel->mLines.Count();
+ if( ( 0 == totalNumberOfGlyphs ) ||
+ ( 0 == totalNumberOfLines ) )
{
return logicalIndex;
}
// Get the position of the first glyph.
const Vector2& position = *( positionsBuffer + firstLogicalGlyphIndex );
- // Whether the glyph can be split, like Latin ligatures fi, ff or Arabic ﻻ.
- const Length numberOfCharacters = *( charactersPerGlyphBuffer + firstLogicalGlyphIndex );
+ // Whether the glyph can be split, like Latin ligatures fi, ff or Arabic (ل + ا).
+ Length numberOfCharacters = *( charactersPerGlyphBuffer + firstLogicalGlyphIndex );
if( direction != LTR )
{
// As characters are being traversed in visual order,
// for right to left ligatures, the character which contains the
// number of glyphs in the table is found first.
// Jump the number of characters to the next glyph is needed.
+
+ if( 0u == numberOfCharacters )
+ {
+ // TODO: This is a workaround to fix an issue with complex characters in the arabic
+ // script like i.e. رّ or الأَبْجَدِيَّة العَرَبِيَّة
+ // There are characters that are not shaped in one glyph but in combination with
+ // the next one generates two of them.
+ // The visual to logical conversion table have characters in different order than
+ // expected even if all of them are arabic.
+
+ // The workaround doesn't fix the issue completely but it prevents the application
+ // to hang in an infinite loop.
+
+ // Find the number of characters.
+ for( GlyphIndex index = firstLogicalGlyphIndex + 1u;
+ ( 0u == numberOfCharacters ) && ( index < totalNumberOfGlyphs ) ;
+ ++index )
+ {
+ numberOfCharacters = *( charactersPerGlyphBuffer + index );
+ }
+
+ if( 2u > numberOfCharacters )
+ {
+ continue;
+ }
+
+ --numberOfCharacters;
+ }
+
visualIndex += numberOfCharacters - 1u;
}
{
// The paragraph direction is right to left.
- if( ( lineIndex != numberOfLines - 1u ) && // is not the last line.
+ if( ( lineIndex != totalNumberOfLines - 1u ) && // is not the last line.
( visualIndex == startCharacter ) )
{
// It places the cursor just after the first character in visual order.
// This branch checks if the closest line is the one with the last '\n'. If it is, it decrements the visual index to place
// the cursor just before the last '\n'.
- if( ( lineIndex != numberOfLines - 1u ) &&
+ if( ( lineIndex != totalNumberOfLines - 1u ) &&
TextAbstraction::IsNewParagraph( *( logicalModel->mText.Begin() + visualIndex - 1u ) ) )
{
--visualIndex;