FontId previousFontId = 0u;
bool isPreviousEmojiScript = false;
- // Whether it's the first set of characters to be validated.
- // Used in case the paragraph starts with characters common to all scripts.
- bool isFirstSetToBeValidated = true;
-
CharacterIndex lastCharacter = startIndex + numberOfCharacters;
for( Length index = startIndex; index < lastCharacter; ++index )
{
description.path.c_str() );
}
#endif
- if (script == TextAbstraction::UNKNOWN)
+ if( script == TextAbstraction::UNKNOWN )
{
script = TextAbstraction::LATIN;
}
// Check first in the cache of default fonts per script and size.
- DefaultFonts* defaultFonts = *( defaultFontPerScriptCacheBuffer + script );
FontId cachedDefaultFontId = 0u;
+ DefaultFonts* defaultFonts = *( defaultFontPerScriptCacheBuffer + script );
if( NULL != defaultFonts )
{
+ // This cache stores fall-back fonts.
cachedDefaultFontId = defaultFonts->FindFont( fontClient,
currentFontDescription,
currentFontPointSize );
// The font is valid if it matches with the default one for the current script and size and it's different than zero.
isValidFont = isValidCachedDefaultFont && ( fontId == cachedDefaultFontId );
+ if( isValidFont )
+ {
+ // Check if the font supports the character.
+ isValidFont = fontClient.IsCharacterSupportedByFont( fontId, character );
+ }
+
bool isCommonScript = false;
bool isEmojiScript = TextAbstraction::EMOJI == script;
currentFontRun.fontId = fontId;
}
-
// If the given font is not valid, it means either:
// - there is no cached font for the current script yet or,
// - the user has set a different font than the default one for the current script or,
if( NULL != validateFontsPerScript )
{
+ // This cache stores valid fonts set by the user.
isValidFont = validateFontsPerScript->IsValidFont( fontId );
+
+ // It may happen that a validated font for a script doesn't have all the glyphs for that script.
+ // i.e a font validated for the CJK script may contain glyphs for the chinese language but not for the Japanese.
+ if( isValidFont )
+ {
+ // Checks if the current character is supported by the font is needed.
+ isValidFont = fontClient.IsCharacterSupportedByFont( fontId, character );
+ }
}
if( !isValidFont ) // (2)
{
- // Use the font client to validate the font.
- const GlyphIndex glyphIndex = fontClient.GetGlyphIndex( fontId, character );
+ // The selected font is not stored in any cache.
- // The font is valid if there is a glyph for that character.
- isValidFont = 0u != glyphIndex;
+ // Checks if the current character is supported by the selected font.
+ isValidFont = fontClient.IsCharacterSupportedByFont( fontId, character );
// Emojis are present in many monochrome fonts; prefer color by default.
if( isValidFont &&
isEmojiScript )
{
+ const GlyphIndex glyphIndex = fontClient.GetGlyphIndex( fontId, character );
+
// For color emojis, the font is valid if the glyph is a color glyph (the bitmap is RGBA).
isValidFont = fontClient.IsColorGlyph( fontId, glyphIndex );
}
validateFontsPerScript->mValidFonts.PushBack( fontId );
}
- if( !isValidFont ) // (3)
+ if( !isValidFont && ( fontId != cachedDefaultFontId ) ) // (3)
{
- // The given font has not been validated.
- int validCharacterIndex = fontClient.GetGlyphIndex(cachedDefaultFontId, character );
+ // The selected font by the user or the platform's default font has failed to validate the character.
+
+ // Checks if the previously discarted cached default font supports the character.
+ bool isValidCachedFont = false;
+ if( isValidCachedDefaultFont )
+ {
+ isValidCachedFont = fontClient.IsCharacterSupportedByFont( cachedDefaultFontId, character );
+ }
- if( isValidCachedDefaultFont && validCharacterIndex != 0u )
+ if( isValidCachedFont )
{
// Use the cached default font for the script if there is one.
fontId = cachedDefaultFontId;
}
#endif
- if( isFirstSetToBeValidated && !isCommonScript )
- {
- currentFontRun.fontId = fontId;
- isFirstSetToBeValidated = false;
- }
-
// The font is now validated.
if( ( fontId != currentFontRun.fontId ) ||
isNewParagraphCharacter )
currentFontRun.characterRun.characterIndex = currentFontRun.characterRun.characterIndex + currentFontRun.characterRun.numberOfCharacters;
currentFontRun.characterRun.numberOfCharacters = 0u;
currentFontRun.fontId = fontId;
-
- if( isNewParagraphCharacter )
- {
- isFirstSetToBeValidated = true;
- }
}
// Add one more character to the run.