Fixed a bug on StyleSheet::addStyle. Now a unique selector can be declared more

than one time without overriding the old one.
UINodes now are only drawn when intersect the viewport ( discard draw if not visible ).
Added a scrolling test.

--HG--
branch : dev

bin/assets/layouts/test.css

@@ -32,7 +32,7 @@ PopUpMenu {
 	minRightMargin: 8dp;
 }
 
-Menu:hover, 
+Menu:hover,
 PopUpMenu:hover,
 Menu::Item:hover,
 Menu::CheckBox:hover,
@@ -44,7 +44,7 @@ Tab:pressed {
 	textColor: #FFF;
 }
 
-Slider { 
+Slider {
 	halfSlider: true;
 	backgroundColor: #555;
 }
@@ -328,3 +328,7 @@ TabWidget {
 	padding: 16dp;
 	layout_marginBottom: 140dp;
 }
+
+#test_5 TextView {
+	padding: 8dp;
+}

bin/assets/layouts/test.xml

@@ -38,13 +38,13 @@
 
 					<PushButton layout_width="wrap_content" layout_height="wrap_content" text="testing padding" layout_gravity="bottom|right" gravity="center" padding="8dp" layout_to_top_of="tmp" />
 					<PushButton id="pbut" text="OK!" textSize="16dp" icon="ok" layout_gravity="left|bottom" gravity="center" layout_width="wrap_content" layout_height="wrap_content" layout_marginBottom="8dp" padding="8dp" layout_to_top_of="tm" />
-					
+
 					<Slider id="slider" orientation="horizontal" halfslider="true" layout_width="200dp" layout_height="wrap_content" layout_to_bottom_of="el1" />
-					
+
 					<ScrollBar id="scrollbar" orientation="horizontal" layout_width="200dp" layout_height="wrap_content" layout_to_bottom_of="slider" />
 
 					<SpinBox id="spinbox" layout_width="200dp" layout_height="wrap_content" layout_to_bottom_of="scrollbar" />
-					
+
 					<TextEdit layout_width="200dp" layout_height="50dp" layout_gravity="bottom|center_horizontal" />
 				</RelativeLayout>
 			</vbox>
@@ -68,10 +68,19 @@
 			<RelativeLayout layout_width="match_parent" layout_height="32dp"><TextView layout_width="wrap_content" layout_height="wrap_content" text="FAQ" /></RelativeLayout>
 			<RelativeLayout layout_width="match_parent" layout_height="32dp"><TextView layout_width="wrap_content" layout_height="wrap_content" text="About Us" /></RelativeLayout>
 		</vbox>
-		
+		<ScrollView id="test_5" layout_width="match_parent" layout_height="match_parent" touchdrag="true">
+			<vbox layout_width="match_parent" layout_height="wrap_content">
+				<TextView text="Test" /><TextView text="Test" /><TextView text="Test" /><TextView text="Test" /><TextView text="Test" /><TextView text="Test" />
+				<TextView text="Test" /><TextView text="Test" /><TextView text="Test" /><TextView text="Test" /><TextView text="Test" /><TextView text="Test" />
+				<TextView text="Test" /><TextView text="Test" /><TextView text="Test" /><TextView text="Test" /><TextView text="Test" /><TextView text="Test" />
+				<TextView text="Test" /><TextView text="Test" /><TextView text="Test" /><TextView text="Test" /><TextView text="Test" /><TextView text="Test" />
+				<TextView text="Test" /><TextView text="Test" /><TextView text="Test" /><TextView text="Test" /><TextView text="Test" /><TextView text="Test" />
+			</vbox>
+		</ScrollView>
 		<Tab name="Padding Test" owns="test_1" />
 		<Tab name="Tabs Test" owns="test_2" />
 		<Tab name="Cascade Test" owns="test_3" />
 		<Tab name="Hover Test" owns="test_4" />
+		<Tab name="Scroll Test" owns="test_5" />
 	</TabWidget>
 </vbox>

src/eepp/ui/css/stylesheet.cpp

@@ -9,7 +9,16 @@ namespace EE { namespace UI { namespace CSS {
 StyleSheet::StyleSheet() {}
 
 void StyleSheet::addStyle( const StyleSheetStyle& node ) {
-	mNodes[ node.getSelector().getName() ] = node;
+	auto nodeIt = mNodes.find( node.getSelector().getName() );
+
+	if ( nodeIt == mNodes.end() ) {
+		mNodes[ node.getSelector().getName() ] = node;
+	} else {
+		StyleSheetStyle& currentNode = nodeIt->second;
+
+		for ( auto& pit : node.getProperties() )
+			currentNode.setProperty( pit.second );
+	}
 }
 
 void StyleSheet::combineStyle( const StyleSheetStyle& node ) {
@@ -18,7 +27,7 @@ void StyleSheet::combineStyle( const StyleSheetStyle& node ) {
 	if ( nodeIt == mNodes.end() ) {
 		addStyle( node );
 	} else {
-		auto currentNode = nodeIt->second;
+		auto& currentNode = nodeIt->second;
 
 		if ( node.getSelector().getSpecificity() > currentNode.getSelector().getSpecificity() ) {
 			for ( auto& pit : node.getProperties() )

src/eepp/ui/uinode.cpp

@@ -620,13 +620,20 @@ void UINode::internalDraw() {
 		if ( mNodeFlags & NODE_FLAG_POSITION_DIRTY )
 			updateScreenPos();
 
+		if ( mNodeFlags & NODE_FLAG_POLYGON_DIRTY )
+			updateWorldPolygon();
+
 		matrixSet();
 
 		clipStart();
 
-		draw();
+		if ( mWorldBounds.intersect( mSceneNode->getWorldBounds() ) ) {
+			draw();
 
-		drawChilds();
+			drawChilds();
+		} else if ( !isClipped() ) {
+			drawChilds();
+		}
 
 		clipEnd();