Text::setFillColor improvements for shaped text.

bin/unit_tests/assets/textfiles/test-arabic-simple.uext

@@ -1 +1 @@
-مَرْحَبًا بِالْعَالَم
+مرحباً بالعالم

include/eepp/graphics/text.hpp

@@ -188,6 +188,8 @@ class EE_API Text {
 
 	void setFillColor( const Color& color, Uint32 from, Uint32 to );
 
+	void setFillColor( const std::vector<Color>& colors );
+
 	void setOutlineColor( const Color& color );
 
 	void setOutlineThickness( Float thickness );

src/eepp/graphics/text.cpp

@@ -1561,8 +1561,8 @@ void Text::draw( const Float& X, const Float& Y, const Vector2f& scale, const Fl
 		invalidate();
 	}
 
-	ensureColorUpdate();
 	ensureGeometryUpdate();
+	ensureColorUpdate();
 
 	if ( mFontStyleConfig.Style & Shadow ) {
 		std::vector<Color> colors;
@@ -2087,8 +2087,15 @@ void Text::setFillColor( const Color& color, Uint32 from, Uint32 to ) {
 	if ( mString.empty() )
 		return;
 
+	ensureGeometryUpdate();
 	ensureColorUpdate();
 
+	size_t numVerts = mVertices.size();
+	if ( mColors.size() < numVerts ) {
+		mColors.resize( numVerts, mFontStyleConfig.FontColor );
+		mColorsNeedUpdate = false;
+	}
+
 	bool underlined = ( mFontStyleConfig.Style & Underlined ) != 0;
 	bool strikeThrough = ( mFontStyleConfig.Style & StrikeThrough ) != 0;
 	std::size_t s = mString.size();
@@ -2098,6 +2105,41 @@ void Text::setFillColor( const Color& color, Uint32 from, Uint32 to ) {
 	}
 
 	if ( from <= to && from < s && to <= s ) {
+#ifdef EE_TEXT_SHAPER_ENABLED
+		if ( TextShaperEnabled && mFontStyleConfig.Font->getType() == FontType::TTF &&
+			 !canSkipShaping( mTextHints ) ) {
+			FontTrueType* rFont = static_cast<FontTrueType*>( mFontStyleConfig.Font );
+			auto layout = TextLayout::layout( mString, rFont, mFontStyleConfig.CharacterSize,
+											  mFontStyleConfig.Style, mTabWidth,
+											  mFontStyleConfig.OutlineThickness );
+			size_t vIdx = 0;
+			bool bold = ( mFontStyleConfig.Style & Bold ) != 0;
+			bool italic = ( mFontStyleConfig.Style & Italic ) != 0;
+
+			for ( const ShapedGlyph& sg : layout->shapedGlyphs ) {
+				if ( mString[sg.stringIndex] == '\t' )
+					continue;
+
+				Glyph glyph =
+					sg.font->getGlyphByIndex( sg.glyphIndex, mFontStyleConfig.CharacterSize, bold,
+											  italic, mFontStyleConfig.OutlineThickness,
+											  rFont->getPage( mFontStyleConfig.CharacterSize ) );
+
+				if ( glyph.bounds.Right > 0 && glyph.bounds.Bottom > 0 ) {
+					if ( vIdx + GLi->quadVertex() <= mColors.size() && sg.stringIndex >= from &&
+						 sg.stringIndex <= to ) {
+						for ( int i = 0; i < GLi->quadVertex(); ++i )
+							mColors[vIdx + i] = color;
+					}
+					vIdx += GLi->quadVertex();
+				}
+			}
+
+			mColorsNeedUpdate = false;
+			return;
+		}
+#endif
+
 		size_t realTo = to + 1;
 		Int32 rpos = from;
 		Int32 lpos = 0;
@@ -2178,6 +2220,78 @@ void Text::setFillColor( const Color& color, Uint32 from, Uint32 to ) {
 	}
 }
 
+void Text::setFillColor( const std::vector<Color>& colors ) {
+	if ( mString.empty() || colors.empty() )
+		return;
+
+	ensureGeometryUpdate();
+	ensureColorUpdate();
+
+	size_t numVerts = mVertices.size();
+	if ( mColors.size() < numVerts ) {
+		mColors.resize( numVerts, mFontStyleConfig.FontColor );
+		mColorsNeedUpdate = false;
+	}
+
+#ifdef EE_TEXT_SHAPER_ENABLED
+	if ( TextShaperEnabled && mFontStyleConfig.Font->getType() == FontType::TTF &&
+		 !canSkipShaping( mTextHints ) ) {
+		FontTrueType* rFont = static_cast<FontTrueType*>( mFontStyleConfig.Font );
+		auto layout = TextLayout::layout( mString, rFont, mFontStyleConfig.CharacterSize,
+										  mFontStyleConfig.Style, mTabWidth,
+										  mFontStyleConfig.OutlineThickness );
+		size_t vIdx = 0;
+		bool bold = ( mFontStyleConfig.Style & Bold ) != 0;
+		bool italic = ( mFontStyleConfig.Style & Italic ) != 0;
+
+		for ( const ShapedGlyph& sg : layout->shapedGlyphs ) {
+			if ( mString[sg.stringIndex] == '\t' )
+				continue;
+
+			Glyph glyph =
+				sg.font->getGlyphByIndex( sg.glyphIndex, mFontStyleConfig.CharacterSize, bold,
+										  italic, mFontStyleConfig.OutlineThickness,
+										  rFont->getPage( mFontStyleConfig.CharacterSize ) );
+
+			if ( glyph.bounds.Right > 0 && glyph.bounds.Bottom > 0 ) {
+				if ( vIdx + GLi->quadVertex() <= mColors.size() &&
+					 sg.stringIndex < colors.size() ) {
+					Color color = colors[sg.stringIndex];
+					if ( mContainsColorEmoji && Font::isEmojiCodePoint( mString[sg.stringIndex] ) )
+						color = Color( 255, 255, 255, color.a );
+					for ( int i = 0; i < GLi->quadVertex(); ++i )
+						mColors[vIdx + i] = color;
+					vIdx += GLi->quadVertex();
+				}
+			}
+		}
+
+		mColorsNeedUpdate = false;
+		return;
+	}
+#endif
+
+	size_t s = mString.size();
+	size_t vIdx = 0;
+
+	for ( size_t i = 0; i < s; i++ ) {
+		String::StringBaseType curChar = mString[i];
+		if ( ' ' == curChar || '\n' == curChar || '\t' == curChar || '\r' == curChar )
+			continue;
+
+		if ( vIdx + GLi->quadVertex() <= mColors.size() && i < colors.size() ) {
+			Color color = colors[i];
+			if ( mContainsColorEmoji && Font::isEmojiCodePoint( curChar ) )
+				color = Color( 255, 255, 255, color.a );
+			for ( int v = 0; v < GLi->quadVertex(); v++ )
+				mColors[vIdx + v] = color;
+			vIdx += GLi->quadVertex();
+		}
+	}
+
+	mColorsNeedUpdate = false;
+}
+
 // Add an underline or strikethrough line to the vertex array
 void Text::addLine( std::vector<VertexCoords>& vertices, Float lineLength, Float lineTop,
 					Float offset, Float thickness, Float outlineThickness, Int32 centerDiffX ) {

src/eepp/ui/doc/syntaxtokenizer.cpp

@@ -951,17 +951,24 @@ Text* SyntaxTokenizer::tokenizeText( const SyntaxDefinition& syntax,
 		text->setString( txt );
 	}
 
+	std::vector<Color> colors( text->getString().size(), text->getFillColor() );
 	size_t start = startIndex;
 	for ( const auto& token : tokens ) {
 		if ( start < endIndex ) {
-			if ( token.len > 0 )
-				text->setFillColor( colorScheme.getSyntaxStyle( token.type ).color, start,
-									std::min( start + token.len, endIndex ) );
+			if ( token.len > 0 ) {
+				Color color = colorScheme.getSyntaxStyle( token.type ).color;
+				size_t end = std::min( start + token.len, endIndex );
+				if ( end > colors.size() )
+					end = colors.size();
+				for ( size_t i = start; i < end; i++ )
+					colors[i] = color;
+			}
 			start += token.len;
 		} else {
 			break;
 		}
 	}
+	text->setFillColor( colors );
 
 	return text;
 }

src/tests/unit_tests/fontrendering.cpp

@@ -728,3 +728,70 @@ cupidatat non proident👽, sunt in culpa qui officia deserunt mollit anim id es
 
 	Engine::destroySingleton();
 }
+
+UTEST( FontRendering, textSetFillColor ) {
+	auto win = Engine::instance()->createWindow(
+		WindowSettings( 1024, 230, "eepp - Text Set Fill Color", WindowStyle::Default,
+						WindowBackend::Default, 32, {}, 1, false, true ) );
+
+	ASSERT_TRUE_MSG( win->isOpen(), "Failed to create Window" );
+
+	UTEST_PRINT_INFO( GLi->getRenderer().c_str() );
+
+	win->setClearColor( RGB( 230, 230, 230 ) );
+
+	FontTrueType* arabicFont =
+		FontTrueType::New( "NotoNaskhArabic-Regular", "assets/fonts/NotoNaskhArabic-Regular.ttf" );
+
+	Text text;
+	text.setFont( arabicFont );
+	text.setFontSize( 64 );
+	text.setAlign( TEXT_ALIGN_CENTER );
+	std::string arabicTxtUtf8;
+	FileSystem::fileGet( "assets/textfiles/test-arabic-simple.uext", arabicTxtUtf8 );
+	String arabicTxt( arabicTxtUtf8 );
+	text.setString( arabicTxt );
+	text.setFillColor( Color::Black );
+
+	const auto runTest = [&]( std::string_view testName ) {
+		win->clear();
+		text.draw( 0, win->getHeight() * 0.5f - text.getTextHeight() * 0.5f );
+		compareImages( utest_state, utest_result, win,
+					   std::string( "eepp-text-set-fill-color-" ) + std::string( testName ) );
+	};
+
+	UTEST_PRINT_STEP( "Text Shaper enabled" );
+	{
+		BoolScopedOp op( Text::TextShaperEnabled, true );
+
+		// Test Vector Fill
+		{
+			std::vector<Color> colors;
+			for ( size_t i = 0; i < arabicTxt.size(); i++ ) {
+				// Alternating colors
+				if ( i % 3 == 0 )
+					colors.push_back( Color::Red );
+				else if ( i % 3 == 1 )
+					colors.push_back( Color::Green );
+				else
+					colors.push_back( Color::Blue );
+			}
+			text.setFillColor( colors );
+			runTest( "vector" );
+		}
+
+		// Test Range Fill
+		{
+			text.setFillColor( Color::Black );
+			// Color "World" (بالعالم) in Red. It's at the end of the string.
+			// "مرحباً" (Hello) is 6 chars + space = 7.
+			// "بالعالم" (World) starts at index 7.
+			if ( arabicTxt.size() > 7 ) {
+				text.setFillColor( Color::Red, 7, arabicTxt.size() );
+			}
+			runTest( "range" );
+		}
+	}
+
+	Engine::destroySingleton();
+}