Merge pull request #12718 from WenhaiLin/v3-label-addchild

Label:Support add child nodes.

AUTHORS

@@ -10,7 +10,7 @@ Core Developers:
     Hao Wu (Wu-Hao)
     Qingkui Hu (samuele3hu)
     Huabing Xu (dabingnn)
-    Wenhai Lin (Dhilan007)
+    Wenhai Lin (WenhaiLin)
     Guanghui Qu (zilongshanren）
     Wensheng Yang (yangws)
     Yulei Liao (dualface)

cocos/2d/CCLabel.cpp

@@ -26,6 +26,7 @@
 #include "2d/CCLabel.h"
 #include "2d/CCFontAtlasCache.h"
 #include "2d/CCSprite.h"
+#include "2d/CCSpriteBatchNode.h"
 #include "2d/CCLabelTextFormatter.h"
 #include "base/ccUTF8.h"
 #include "platform/CCFileUtils.h"
@@ -42,6 +43,99 @@ NS_CC_BEGIN
 
 const int Label::DistanceFieldFontSize = 50;
 
+/**
+ * LabelLetter used to update the quad in texture atlas without SpriteBatchNode.
+ */
+class LabelLetter : public Sprite
+{
+public:
+    LabelLetter()
+    {
+        _textureAtlas = nullptr;
+    }
+
+    static LabelLetter* createWithTexture(Texture2D *texture, const Rect& rect, bool rotated = false)
+    {
+        auto letter = new (std::nothrow) LabelLetter();
+        if (letter && letter->initWithTexture(texture, rect, rotated))
+        {
+            letter->setVisible(false);
+            letter->autorelease();
+            return letter;
+        }
+        CC_SAFE_DELETE(letter);
+        return nullptr;
+    }
+
+    virtual void updateTransform() override
+    {
+        if (isDirty())
+        {
+            _transformToBatch = getNodeToParentTransform();
+            Size &size = _rect.size;
+
+            float x1 = _offsetPosition.x;
+            float y1 = _offsetPosition.y;
+            float x2 = x1 + size.width;
+            float y2 = y1 + size.height;
+            float x = _transformToBatch.m[12];
+            float y = _transformToBatch.m[13];
+
+            float cr = _transformToBatch.m[0];
+            float sr = _transformToBatch.m[1];
+            float cr2 = _transformToBatch.m[5];
+            float sr2 = -_transformToBatch.m[4];
+            float ax = x1 * cr - y1 * sr2 + x;
+            float ay = x1 * sr + y1 * cr2 + y;
+
+            float bx = x2 * cr - y1 * sr2 + x;
+            float by = x2 * sr + y1 * cr2 + y;
+            float cx = x2 * cr - y2 * sr2 + x;
+            float cy = x2 * sr + y2 * cr2 + y;
+            float dx = x1 * cr - y2 * sr2 + x;
+            float dy = x1 * sr + y2 * cr2 + y;
+
+            _quad.bl.vertices.set(SPRITE_RENDER_IN_SUBPIXEL(ax), SPRITE_RENDER_IN_SUBPIXEL(ay), _positionZ);
+            _quad.br.vertices.set(SPRITE_RENDER_IN_SUBPIXEL(bx), SPRITE_RENDER_IN_SUBPIXEL(by), _positionZ);
+            _quad.tl.vertices.set(SPRITE_RENDER_IN_SUBPIXEL(dx), SPRITE_RENDER_IN_SUBPIXEL(dy), _positionZ);
+            _quad.tr.vertices.set(SPRITE_RENDER_IN_SUBPIXEL(cx), SPRITE_RENDER_IN_SUBPIXEL(cy), _positionZ);
+
+            if (_textureAtlas)
+            {
+                _textureAtlas->updateQuad(&_quad, _atlasIndex);
+            }
+
+            _recursiveDirty = false;
+            setDirty(false);
+        }
+
+        Node::updateTransform();
+    }
+
+    virtual void updateColor()
+    {
+        if (_textureAtlas == nullptr)
+        {
+            return;
+        }
+
+        Color4B color4(_displayedColor.r, _displayedColor.g, _displayedColor.b, _displayedOpacity);
+        // special opacity for premultiplied textures
+        if (_opacityModifyRGB)
+        {
+            color4.r *= _displayedOpacity / 255.0f;
+            color4.g *= _displayedOpacity / 255.0f;
+            color4.b *= _displayedOpacity / 255.0f;
+        }
+        _quad.bl.colors = color4;
+        _quad.br.colors = color4;
+        _quad.tl.colors = color4;
+        _quad.tr.colors = color4;
+
+        _textureAtlas->updateQuad(&_quad, _atlasIndex);
+    }
+};
+
 Label* Label::create()
 {
     auto ret = new (std::nothrow) Label();
@@ -257,6 +351,7 @@ Label::Label(FontAtlas *atlas /* = nullptr */, TextHAlignment hAlignment /* = Te
 , _effectColorF(Color4F::BLACK)
 , _uniformEffectColor(0)
 , _shadowDirty(false)
+, _blendFunc(BlendFunc::ALPHA_PREMULTIPLIED)
 , _insideBounds(true)
 {
     setAnchorPoint(Vec2::ANCHOR_MIDDLE);
@@ -265,9 +360,11 @@ Label::Label(FontAtlas *atlas /* = nullptr */, TextHAlignment hAlignment /* = Te
     _purgeTextureListener = EventListenerCustom::create(FontAtlas::CMD_PURGE_FONTATLAS, [this](EventCustom* event){
         if (_fontAtlas && _currentLabelType == LabelType::TTF && event->getUserData() == _fontAtlas)
         {
-            Node::removeAllChildrenWithCleanup(true);
+            for (auto it : _letters)
+            {
+                it.second->setTexture(nullptr);
+            }
             _batchNodes.clear();
-            _batchNodes.push_back(this);
 
             if (_fontAtlas)
             {
@@ -282,6 +379,10 @@ Label::Label(FontAtlas *atlas /* = nullptr */, TextHAlignment hAlignment /* = Te
         {
             _fontAtlas = nullptr;
             this->setTTFConfig(_fontConfig);
+            for (auto it : _letters)
+            {
+                getLetter(it.first);
+            }
         }
     });
     _eventDispatcher->addEventListenerWithFixedPriority(_resetTextureListener, 2);
@@ -299,6 +400,8 @@ Label::~Label()
     _eventDispatcher->removeEventListener(_resetTextureListener);
 
     CC_SAFE_RELEASE_NULL(_reusedLetter);
+    CC_SAFE_RELEASE_NULL(_textSprite);
+    CC_SAFE_RELEASE_NULL(_shadowNode);
 }
 
 void Label::reset()
@@ -311,7 +414,6 @@ void Label::reset()
     _systemFontSize = 12;
 
     _batchNodes.clear();
-    _batchNodes.push_back(this);
 
     if (_fontAtlas)
     {
@@ -384,16 +486,6 @@ void Label::setFontAtlas(FontAtlas* atlas,bool distanceFieldEnabled /* = false *
     }
 
     _fontAtlas = atlas;
-
-    if (_textureAtlas)
-    {
-        _textureAtlas->setTexture(_fontAtlas->getTexture(0));
-    }
-    else
-    {
-        SpriteBatchNode::initWithTexture(_fontAtlas->getTexture(0), 30);
-    }
-
     if (_reusedLetter == nullptr)
     {
         _reusedLetter = Sprite::create();
@@ -401,7 +493,6 @@ void Label::setFontAtlas(FontAtlas* atlas,bool distanceFieldEnabled /* = false *
         _reusedLetter->retain();
         _reusedLetter->setAnchorPoint(Vec2::ANCHOR_TOP_LEFT);
     }
-    _reusedLetter->setBatchNode(this);
 
     if (_fontAtlas)
     {
@@ -594,12 +685,21 @@ void Label::alignText()
         for (auto index = _batchNodes.size(); index < textures.size(); ++index)
         {
             auto batchNode = SpriteBatchNode::createWithTexture(textures.at(index));
-            batchNode->setAnchorPoint(Vec2::ANCHOR_TOP_LEFT);
+            if (batchNode)
-            batchNode->setPosition(Vec2::ZERO);
+            {
-            Node::addChild(batchNode,0,Node::INVALID_TAG);
+                _blendFunc = batchNode->getBlendFunc();
-            _batchNodes.push_back(batchNode);
+                batchNode->setAnchorPoint(Vec2::ANCHOR_TOP_LEFT);
+                batchNode->setPosition(Vec2::ZERO);
+                _batchNodes.pushBack(batchNode);
+            }
         }
     }
+    if (_batchNodes.empty())
+    {
+        return;
+    }
+    _reusedLetter->setBatchNode(_batchNodes.at(0));
+
     LabelTextFormatter::createStringSprites(this);    
     if(_maxLineWidth > 0 && _contentSize.width > _maxLineWidth && LabelTextFormatter::multilineText(this) )      
         LabelTextFormatter::createStringSprites(this);
@@ -607,39 +707,36 @@ void Label::alignText()
     if(_labelWidth > 0 || (_currNumLines > 1 && _hAlignment != TextHAlignment::LEFT))
         LabelTextFormatter::alignText(this);
 
-    if (!_children.empty())
+    if (!_letters.empty())
     {
-        int strLen = static_cast<int>(_currentUTF16String.length());
         Rect uvRect;
         Sprite* letterSprite;
-        for (auto index = 0; index < _children.size();) {
+        int letterIndex;
-            auto child = _children.at(index);
+
-            int tag = child->getTag();
+        for (auto it = _letters.begin(); it != _letters.end();)
-            if (tag >= strLen)
+        {
+            letterIndex = it->first;
+            letterSprite = it->second;
+
+            if (letterIndex >= _limitShowCount)
             {
-                child->removeFromParentAndCleanup(true);
+                Node::removeChild(letterSprite, true);
-            }
+                it = _letters.erase(it);
-            else if (tag >= 0)
-            {
-                letterSprite = dynamic_cast<Sprite*>(child);
-                if (letterSprite)
-                {
-                    auto& letterDef = _lettersInfo[tag].def;
-                    uvRect.size.height = letterDef.height;
-                    uvRect.size.width = letterDef.width;
-                    uvRect.origin.x = letterDef.U;
-                    uvRect.origin.y = letterDef.V;
-                    
-                    letterSprite->setBatchNode(_batchNodes[letterDef.textureID]);
-                    letterSprite->setTextureRect(uvRect, false, uvRect.size);
-                    letterSprite->setPosition(_lettersInfo[tag].position.x + letterDef.width/2,
-                                              _lettersInfo[tag].position.y - letterDef.height/2);
-                }
-                ++index;
             }
             else
             {
-                ++index;
+                auto& letterDef = _lettersInfo[letterIndex].def;
+                uvRect.size.height = letterDef.height;
+                uvRect.size.width = letterDef.width;
+                uvRect.origin.x = letterDef.U;
+                uvRect.origin.y = letterDef.V;
+
+                letterSprite->setBatchNode(_batchNodes.at(letterDef.textureID));
+                letterSprite->setTextureRect(uvRect, false, uvRect.size);
+                letterSprite->setPosition(_lettersInfo[letterIndex].position.x + letterDef.width / 2,
+                    _lettersInfo[letterIndex].position.y - letterDef.height / 2);
+
+                ++it;
             }
         }
     }
@@ -700,9 +797,9 @@ void Label::updateQuads()
             _reusedLetter->setTextureRect(_reusedRect,false,_reusedRect.size);
 
             _reusedLetter->setPosition(_lettersInfo[ctr].position);
-            index = static_cast<int>(_batchNodes[letterDef.textureID]->getTextureAtlas()->getTotalQuads());
+            index = static_cast<int>(_batchNodes.at(letterDef.textureID)->getTextureAtlas()->getTotalQuads());
             _lettersInfo[ctr].atlasIndex = index;
-            _batchNodes[letterDef.textureID]->insertQuadFromSprite(_reusedLetter,index);
+            _batchNodes.at(letterDef.textureID)->insertQuadFromSprite(_reusedLetter,index);
         }     
     }
 }
@@ -738,16 +835,6 @@ bool Label::recordPlaceholderInfo(int spriteIndex)
     return false;
 }
 
-void Label::addChild(Node * child, int zOrder/* =0 */, int tag/* =0 */)
-{
-    CCASSERT(0, "addChild: is not supported on Label.");
-}
-
-void Label::sortAllChildren()
-{
-    // Label ignore sort children
-}
-
 void Label::enableGlow(const Color4B& glowColor)
 {
     if (_currentLabelType == LabelType::TTF)
@@ -821,7 +908,7 @@ void Label::enableShadow(const Color4B& shadowColor /* = Color4B::BLACK */,const
         {
             if (shadowColor != _shadowColor4F)
             {
-                Node::removeChild(_shadowNode, true);
+                _shadowNode->release();
                 _shadowNode = nullptr;
                 createShadowSpriteForSystemFont();
             }
@@ -872,11 +959,7 @@ void Label::disableEffect(LabelEffect effect)
         if (_shadowEnabled)
         {
             _shadowEnabled = false;
-            if (_shadowNode)
+            CC_SAFE_RELEASE_NULL(_shadowNode);
-            {
-                Node::removeChild(_shadowNode, true);
-                _shadowNode = nullptr;
-            }
         }
         break;
     case cocos2d::LabelEffect::GLOW:
@@ -904,121 +987,6 @@ void Label::setFontScale(float fontScale)
     Node::setScale(_fontScale);
 }
 
-void Label::onDraw(const Mat4& transform, bool transformUpdated)
-{
-    // Optimization: Fast Dispatch
-    if( _textureAtlas == NULL || (_batchNodes.size() == 1 && _textureAtlas->getTotalQuads() == 0) )
-    {
-        return;
-    }
-
-    auto glprogram = getGLProgram();
-    glprogram->use();
-    GL::blendFunc( _blendFunc.src, _blendFunc.dst );
-
-    if (_shadowEnabled)
-    {
-        if (_currentLabelType == LabelType::TTF)
-        {
-            glprogram->setUniformLocationWith4f(_uniformTextColor,
-                _shadowColor4F.r, _shadowColor4F.g, _shadowColor4F.b, _shadowColor4F.a);
-            if (_currLabelEffect == LabelEffect::OUTLINE || _currLabelEffect == LabelEffect::GLOW)
-            {
-                glprogram->setUniformLocationWith4f(_uniformEffectColor,
-                    _shadowColor4F.r, _shadowColor4F.g, _shadowColor4F.b, _shadowColor4F.a);
-            }
-
-            getGLProgram()->setUniformsForBuiltins(_shadowTransform);
-            for (const auto &child : _children)
-            {
-                child->updateTransform();
-            }
-            for (const auto& batchNode : _batchNodes)
-            {
-                batchNode->getTextureAtlas()->drawQuads();
-            }
-        }
-        else
-        {
-            Color3B oldColor = _realColor;
-            GLubyte oldOPacity = _displayedOpacity;
-            _displayedOpacity = _shadowOpacity;
-            setColor(_shadowColor3B);
-
-            getGLProgram()->setUniformsForBuiltins(_shadowTransform);
-            for (const auto &child : _children)
-            {
-                child->updateTransform();
-            }
-            for (const auto& batchNode : _batchNodes)
-            {
-                batchNode->getTextureAtlas()->drawQuads();
-            }
-
-            _displayedOpacity = oldOPacity;
-            setColor(oldColor);
-        }
-    }
-
-    glprogram->setUniformsForBuiltins(transform);
-    for(const auto &child: _children)
-    {
-        child->updateTransform();
-    }
-    
-    if (_currentLabelType == LabelType::TTF)
-    {
-        switch (_currLabelEffect) {
-            case LabelEffect::OUTLINE:
-                //draw text with outline
-                glprogram->setUniformLocationWith4f(_uniformTextColor,
-                                                    _textColorF.r,_textColorF.g,_textColorF.b,_textColorF.a);
-                glprogram->setUniformLocationWith4f(_uniformEffectColor,
-                                                    _effectColorF.r, _effectColorF.g, _effectColorF.b, _effectColorF.a);
-                for (const auto& batchNode:_batchNodes)
-                {
-                    batchNode->getTextureAtlas()->drawQuads();
-                }
-                
-                //draw text without outline
-                glprogram->setUniformLocationWith4f(_uniformEffectColor,
-                                                    _effectColorF.r, _effectColorF.g, _effectColorF.b, 0.f);
-                break;
-            case LabelEffect::GLOW:
-                glprogram->setUniformLocationWith4f(_uniformEffectColor,
-                                                    _effectColorF.r, _effectColorF.g, _effectColorF.b, _effectColorF.a);
-            case LabelEffect::NORMAL:
-                glprogram->setUniformLocationWith4f(_uniformTextColor,
-                                                    _textColorF.r,_textColorF.g,_textColorF.b,_textColorF.a);
-                break;
-            default:
-                break;
-        }
-    }
-
-    for (const auto& batchNode:_batchNodes)
-    {
-        batchNode->getTextureAtlas()->drawQuads();
-    }
-}
-
-void Label::draw(Renderer *renderer, const Mat4 &transform, uint32_t flags)
-{
-    // Don't do calculate the culling if the transform was not updated
-    bool transformUpdated = flags & FLAGS_TRANSFORM_DIRTY;
-#if CC_USE_CULLING
-    _insideBounds = transformUpdated ? renderer->checkVisibility(transform, _contentSize) : _insideBounds;
-
-    if(_insideBounds)
-#endif
-    {
-        _customCommand.init(_globalZOrder, transform, flags);
-        _customCommand.func = CC_CALLBACK_0(Label::onDraw, this, transform, transformUpdated);
-
-        renderer->addCommand(&_customCommand);
-    }
-}
-
 void Label::createSpriteForSystemFont()
 {
     _currentLabelType = LabelType::STRING_TEXTURE;
@@ -1078,8 +1046,7 @@ void Label::createSpriteForSystemFont()
         _textSprite->setBlendFunc(_blendFunc);
     }
 
-    Node::addChild(_textSprite, 0, Node::INVALID_TAG);
+    _textSprite->retain();
-
     _textSprite->updateDisplayedColor(_displayedColor);
     _textSprite->updateDisplayedOpacity(_displayedOpacity);
 }
@@ -1117,8 +1084,8 @@ void Label::createShadowSpriteForSystemFont()
         _shadowNode->setCameraMask(getCameraMask());
         _shadowNode->setAnchorPoint(Vec2::ANCHOR_BOTTOM_LEFT);
         _shadowNode->setPosition(_shadowOffset.width, _shadowOffset.height);
-        Node::addChild(_shadowNode, 0, Node::INVALID_TAG);
 
+        _shadowNode->retain();
         _shadowNode->updateDisplayedColor(_displayedColor);
         _shadowNode->updateDisplayedOpacity(_displayedOpacity);
     }
@@ -1126,7 +1093,7 @@ void Label::createShadowSpriteForSystemFont()
 
 void Label::setCameraMask(unsigned short mask, bool applyChildren)
 {
-    SpriteBatchNode::setCameraMask(mask, applyChildren);
+    Node::setCameraMask(mask, applyChildren);
     
     if (_textSprite)
     {
@@ -1163,7 +1130,6 @@ void Label::updateContent()
         if (_fontAtlas)
         {
             _batchNodes.clear();
-            _batchNodes.push_back(this);
 
             FontAtlasCache::releaseFontAtlas(_fontAtlas);
             _fontAtlas = nullptr;
@@ -1172,16 +1138,8 @@ void Label::updateContent()
         _systemFontDirty = false;
     }
 
-    if (_textSprite)
+    CC_SAFE_RELEASE_NULL(_textSprite);
-    {
+    CC_SAFE_RELEASE_NULL(_shadowNode);
-        Node::removeChild(_textSprite, true);
-        _textSprite = nullptr;
-        if (_shadowNode)
-        {
-            Node::removeChild(_shadowNode, true);
-            _shadowNode = nullptr;
-        }
-    }
 
     if (_fontAtlas)
     {
@@ -1206,9 +1164,127 @@ void Label::updateContent()
     _contentDirty = false;
 }
 
+void Label::onDrawShadow(GLProgram* glProgram)
+{
+    if (_currentLabelType == LabelType::TTF)
+    {
+        glProgram->setUniformLocationWith4f(_uniformTextColor,
+            _shadowColor4F.r, _shadowColor4F.g, _shadowColor4F.b, _shadowColor4F.a);
+        if (_currLabelEffect == LabelEffect::OUTLINE || _currLabelEffect == LabelEffect::GLOW)
+        {
+            glProgram->setUniformLocationWith4f(_uniformEffectColor,
+                _shadowColor4F.r, _shadowColor4F.g, _shadowColor4F.b, _shadowColor4F.a);
+        }
+
+        glProgram->setUniformsForBuiltins(_shadowTransform);
+        for (auto it : _letters)
+        {
+            it.second->updateTransform();
+        }
+        for (const auto& batchNode : _batchNodes)
+        {
+            batchNode->getTextureAtlas()->drawQuads();
+        }
+    }
+    else
+    {
+        Color3B oldColor = _realColor;
+        GLubyte oldOPacity = _displayedOpacity;
+        _displayedOpacity = _shadowOpacity;
+        setColor(_shadowColor3B);
+
+        glProgram->setUniformsForBuiltins(_shadowTransform);
+        for (auto it : _letters)
+        {
+            it.second->updateTransform();
+        }
+        for (const auto& batchNode : _batchNodes)
+        {
+            batchNode->getTextureAtlas()->drawQuads();
+        }
+
+        _displayedOpacity = oldOPacity;
+        setColor(oldColor);
+    }
+}
+
+void Label::onDraw(const Mat4& transform, bool transformUpdated)
+{
+    auto glprogram = getGLProgram();
+    glprogram->use();
+    GL::blendFunc(_blendFunc.src, _blendFunc.dst);
+
+    if (_shadowEnabled)
+    {
+        onDrawShadow(glprogram);
+    }
+
+    glprogram->setUniformsForBuiltins(transform);
+    for (auto it : _letters)
+    {
+        it.second->updateTransform();
+    }
+
+    if (_currentLabelType == LabelType::TTF)
+    {
+        switch (_currLabelEffect) {
+        case LabelEffect::OUTLINE:
+            //draw text with outline
+            glprogram->setUniformLocationWith4f(_uniformTextColor,
+                _textColorF.r, _textColorF.g, _textColorF.b, _textColorF.a);
+            glprogram->setUniformLocationWith4f(_uniformEffectColor,
+                _effectColorF.r, _effectColorF.g, _effectColorF.b, _effectColorF.a);
+            for (const auto& batchNode : _batchNodes)
+            {
+                batchNode->getTextureAtlas()->drawQuads();
+            }
+
+            //draw text without outline
+            glprogram->setUniformLocationWith4f(_uniformEffectColor,
+                _effectColorF.r, _effectColorF.g, _effectColorF.b, 0.f);
+            break;
+        case LabelEffect::GLOW:
+            glprogram->setUniformLocationWith4f(_uniformEffectColor,
+                _effectColorF.r, _effectColorF.g, _effectColorF.b, _effectColorF.a);
+        case LabelEffect::NORMAL:
+            glprogram->setUniformLocationWith4f(_uniformTextColor,
+                _textColorF.r, _textColorF.g, _textColorF.b, _textColorF.a);
+            break;
+        default:
+            break;
+        }
+    }
+
+    for (const auto& batchNode : _batchNodes)
+    {
+        batchNode->getTextureAtlas()->drawQuads();
+    }
+}
+
+void Label::draw(Renderer *renderer, const Mat4 &transform, uint32_t flags)
+{
+    if (_batchNodes.empty() || _limitShowCount <= 0)
+    {
+        return;
+    }
+    // Don't do calculate the culling if the transform was not updated
+    bool transformUpdated = flags & FLAGS_TRANSFORM_DIRTY;
+#if CC_USE_CULLING
+    _insideBounds = transformUpdated ? renderer->checkVisibility(transform, _contentSize) : _insideBounds;
+
+    if (_insideBounds)
+#endif
+    {
+        _customCommand.init(_globalZOrder, transform, flags);
+        _customCommand.func = CC_CALLBACK_0(Label::onDraw, this, transform, transformUpdated);
+
+        renderer->addCommand(&_customCommand);
+    }
+}
+
 void Label::visit(Renderer *renderer, const Mat4 &parentTransform, uint32_t parentFlags)
 {
-    if (! _visible || _originalUTF8String.empty())
+    if (! _visible || (_originalUTF8String.empty() && _children.empty()) )
     {
         return;
     }
@@ -1220,7 +1296,8 @@ void Label::visit(Renderer *renderer, const Mat4 &parentTransform, uint32_t pare
 
     uint32_t flags = processParentFlags(parentTransform, parentFlags);
 
-    if (_shadowEnabled && _shadowBlurRadius <= 0 && (_shadowDirty || (flags & FLAGS_DIRTY_MASK)))
+    if (!_originalUTF8String.empty() && _shadowEnabled && _shadowBlurRadius <= 0 
+        && (_shadowDirty || (flags & FLAGS_DIRTY_MASK)))
     {
         _position.x += _shadowOffset.width;
         _position.y += _shadowOffset.height;
@@ -1235,7 +1312,8 @@ void Label::visit(Renderer *renderer, const Mat4 &parentTransform, uint32_t pare
         _shadowDirty = false;
     }
 
-    if (!_textSprite && !isVisitableByVisitingCamera())
+    bool visibleByCamera = isVisitableByVisitingCamera();
+    if (_children.empty() && !_textSprite && !visibleByCamera)
     {
         return;
     }
@@ -1246,6 +1324,41 @@ void Label::visit(Renderer *renderer, const Mat4 &parentTransform, uint32_t pare
     _director->pushMatrix(MATRIX_STACK_TYPE::MATRIX_STACK_MODELVIEW);
     _director->loadMatrix(MATRIX_STACK_TYPE::MATRIX_STACK_MODELVIEW, _modelViewTransform);
     
+    if (!_children.empty())
+    {
+        sortAllChildren();
+
+        int i = 0;
+        // draw children zOrder < 0
+        for (; i < _children.size(); i++)
+        {
+            auto node = _children.at(i);
+
+            if (node && node->getLocalZOrder() < 0)
+                node->visit(renderer, _modelViewTransform, flags);
+            else
+                break;
+        }
+        // self draw
+        if (visibleByCamera)
+            this->drawSelf(renderer, flags);
+
+        for (auto it = _children.cbegin() + i; it != _children.cend(); ++it)
+        {
+            (*it)->visit(renderer, _modelViewTransform, flags);
+        }
+            
+    }
+    else if (visibleByCamera)
+    {
+        this->drawSelf(renderer, flags);
+    }
+
+    _director->popMatrix(MATRIX_STACK_TYPE::MATRIX_STACK_MODELVIEW);
+}
+
+void Label::drawSelf(Renderer* renderer, uint32_t flags)
+{
     if (_textSprite)
     {
         if (_shadowNode)
@@ -1258,12 +1371,6 @@ void Label::visit(Renderer *renderer, const Mat4 &parentTransform, uint32_t pare
     {
         draw(renderer, _modelViewTransform, flags);
     }
-
-    _director->popMatrix(MATRIX_STACK_TYPE::MATRIX_STACK_MODELVIEW);
-    
-    // FIX ME: Why need to set _orderOfArrival to 0??
-    // Please refer to https://github.com/cocos2d/cocos2d-x/pull/6920
-    // setOrderOfArrival(0);
 }
 
 void Label::setSystemFontName(const std::string& systemFont)
@@ -1287,45 +1394,63 @@ void Label::setSystemFontSize(float fontSize)
 ///// PROTOCOL STUFF
 Sprite * Label::getLetter(int letterIndex)
 {
-    if (_systemFontDirty || _currentLabelType == LabelType::STRING_TEXTURE)
+    Sprite* letter = nullptr;
+    do 
     {
-        return nullptr;
+        if (_systemFontDirty || _currentLabelType == LabelType::STRING_TEXTURE)
-    }
-
-    if (_contentDirty)
-    {
-        updateContent();
-    }
-    
-    if (! _textSprite && letterIndex < _limitShowCount)
-    {
-        const auto &letter = _lettersInfo[letterIndex];
-
-        if(! letter.def.validDefinition)
-            return nullptr;
-
-        Sprite* sp = static_cast<Sprite*>(this->getChildByTag(letterIndex));
-
-        if (!sp)
         {
-            Rect uvRect;
+            break;
-            uvRect.size.height = letter.def.height;
+        }  
-            uvRect.size.width  = letter.def.width;
-            uvRect.origin.x    = letter.def.U;
-            uvRect.origin.y    = letter.def.V;
 
-            sp = Sprite::createWithTexture(_fontAtlas->getTexture(letter.def.textureID),uvRect);
+        auto contentDirty = _contentDirty;
-            sp->setBatchNode(_batchNodes[letter.def.textureID]);
+        if (contentDirty)
-            sp->setPosition(letter.position.x + uvRect.size.width / 2,
+        {
-                letter.position.y - uvRect.size.height / 2);
+            updateContent();
-            sp->setOpacity(_realOpacity);
-
-            _batchNodes[letter.def.textureID]->addSpriteWithoutQuad(sp, letter.atlasIndex, letterIndex);
         }
-        return sp;
-    }
 
-    return nullptr;
+        if (_textSprite == nullptr && letterIndex < _limitShowCount)
+        {
+            const auto &letterInfo = _lettersInfo[letterIndex];
+            if (!letterInfo.def.validDefinition)
+            {
+                break;
+            } 
+
+            if (_letters.find(letterIndex) != _letters.end())
+            {
+                letter = _letters[letterIndex];
+            }
+
+            auto textureID = letterInfo.def.textureID;
+            Rect uvRect;
+            uvRect.size.height = letterInfo.def.height;
+            uvRect.size.width = letterInfo.def.width;
+            uvRect.origin.x = letterInfo.def.U;
+            uvRect.origin.y = letterInfo.def.V;
+
+            if (letter == nullptr)
+            {
+                letter = LabelLetter::createWithTexture(_fontAtlas->getTexture(textureID), uvRect);
+                letter->setTextureAtlas(_batchNodes.at(textureID)->getTextureAtlas());
+                letter->setAtlasIndex(letterInfo.atlasIndex);
+
+                letter->setPosition(letterInfo.position.x + uvRect.size.width / 2,
+                    letterInfo.position.y - uvRect.size.height / 2);
+                letter->setOpacity(_realOpacity);
+                addChild(letter);
+
+                _letters[letterIndex] = letter;
+            }
+            else if (contentDirty)
+            {
+                letter->setTexture(_fontAtlas->getTexture(textureID));
+                letter->setTextureRect(uvRect, false, uvRect.size);
+                letter->setTextureAtlas(_batchNodes.at(textureID)->getTextureAtlas());
+            }
+        }
+    } while (false);
+
+    return letter;
 }
 
 void Label::setLineHeight(float height)
@@ -1416,10 +1541,7 @@ void Label::setOpacityModifyRGB(bool isOpacityModifyRGB)
 
 void Label::updateDisplayedColor(const Color3B& parentColor)
 {
-    _displayedColor.r = _realColor.r * parentColor.r/255.0;
+    Node::updateDisplayedColor(parentColor);
-    _displayedColor.g = _realColor.g * parentColor.g/255.0;
-    _displayedColor.b = _realColor.b * parentColor.b/255.0;
-    updateColor();
 
     if (_textSprite)
     {
@@ -1433,8 +1555,7 @@ void Label::updateDisplayedColor(const Color3B& parentColor)
 
 void Label::updateDisplayedOpacity(GLubyte parentOpacity)
 {
-    _displayedOpacity = _realOpacity * parentOpacity/255.0;
+    Node::updateDisplayedOpacity(parentOpacity);
-    updateColor();
 
     if (_textSprite)
     {
@@ -1468,7 +1589,7 @@ void Label::setTextColor(const Color4B &color)
 
 void Label::updateColor()
 {
-    if (nullptr == _textureAtlas)
+    if (_batchNodes.empty())
     {
         return;
     }
@@ -1539,4 +1660,23 @@ void Label::setBlendFunc(const BlendFunc &blendFunc)
     }
 }
 
+void Label::removeAllChildrenWithCleanup(bool cleanup)
+{
+    Node::removeAllChildrenWithCleanup(cleanup);
+    _letters.clear();
+}
+
+void Label::removeChild(Node* child, bool cleanup /* = true */)
+{
+    Node::removeChild(child, cleanup);
+    for (auto it : _letters)
+    {
+        if (it.second == child)
+        {
+            _letters.erase(it.first);
+            break;
+        }
+    }
+}
+
 NS_CC_END

cocos/2d/CCLabel.h

@@ -26,7 +26,7 @@
 #ifndef _COCOS2D_CCLABEL_H_
 #define _COCOS2D_CCLABEL_H_
 
-#include "2d/CCSpriteBatchNode.h"
+#include "2d/CCNode.h"
 #include "renderer/CCCustomCommand.h"
 #include "2d/CCFontAtlas.h"
 #include "base/ccTypes.h"
@@ -83,8 +83,11 @@ typedef struct _ttfConfig
     }
 }TTFConfig;
 
+class Sprite;
+class SpriteBatchNode;
+
 /**
- * @brief Label is a subclass of SpriteBatchNode that knows how to render text labels.
+ * @brief Label is a subclass of Node that knows how to render text labels.
  *
  * Label can be created with:
  * - A true type font file.
@@ -99,7 +102,7 @@ typedef struct _ttfConfig
  * - http://www.angelcode.com/products/bmfont/ (Free, Windows only)
  * @js NA
  */
-class CC_DLL Label : public SpriteBatchNode, public LabelProtocol
+class CC_DLL Label : public Node, public LabelProtocol, public BlendProtocol
 {
 public:
     static const int DistanceFieldFontSize;
@@ -435,6 +438,7 @@ public:
 
     FontAtlas* getFontAtlas() { return _fontAtlas; }
 
+    virtual const BlendFunc& getBlendFunc() const override { return _blendFunc; }
     virtual void setBlendFunc(const BlendFunc &blendFunc) override;
 
     virtual bool isOpacityModifyRGB() const override;
@@ -448,9 +452,6 @@ public:
     virtual float getScaleX() const override;
     virtual float getScaleY() const override;
 
-    virtual void addChild(Node * child, int zOrder=0, int tag=0) override;
-    virtual void sortAllChildren() override;
-
     virtual std::string getDescription() const override;
 
     virtual const Size& getContentSize() const override;
@@ -462,6 +463,9 @@ public:
 
     virtual void setCameraMask(unsigned short mask, bool applyChildren = true) override;
 
+    virtual void removeAllChildrenWithCleanup(bool cleanup) override;
+    virtual void removeChild(Node* child, bool cleanup = true) override;
+
     CC_DEPRECATED_ATTRIBUTE static Label* create(const std::string& text, const std::string& font, float fontSize,
         const Size& dimensions = Size::ZERO, TextHAlignment hAlignment = TextHAlignment::LEFT,
         TextVAlignment vAlignment = TextVAlignment::TOP);
@@ -491,6 +495,7 @@ CC_CONSTRUCTOR_ACCESS:
 
 protected:
     void onDraw(const Mat4& transform, bool transformUpdated);
+    void onDrawShadow(GLProgram* glProgram);
 
     struct LetterInfo
     {
@@ -533,6 +538,8 @@ protected:
 
     void reset();
 
+    void drawSelf(Renderer* renderer, uint32_t flags);
+
     std::string _bmFontPath;
 
     bool _isOpacityModifyRGB;
@@ -543,7 +550,7 @@ protected:
     float         _systemFontSize;
     LabelType _currentLabelType;
 
-    std::vector<SpriteBatchNode*> _batchNodes;
+    Vector<SpriteBatchNode*> _batchNodes;
     FontAtlas *                   _fontAtlas;
     std::vector<LetterInfo>       _lettersInfo;
     EventListenerCustom* _purgeTextureListener;
@@ -607,9 +614,12 @@ protected:
 
     bool _clipEnabled;
     bool _blendFuncDirty;
+    BlendFunc _blendFunc;
     /// whether or not the sprite was inside bounds the previous frame
     bool _insideBounds;
 
+    std::unordered_map<int, Sprite*> _letters;
+
 private:
     CC_DISALLOW_COPY_AND_ASSIGN(Label);
 

cocos/2d/CCSprite.cpp

@@ -43,12 +43,6 @@ THE SOFTWARE.
 
 NS_CC_BEGIN
 
-#if CC_SPRITEBATCHNODE_RENDER_SUBPIXEL
-#define RENDER_IN_SUBPIXEL
-#else
-#define RENDER_IN_SUBPIXEL(__ARGS__) (ceil(__ARGS__))
-#endif
-
 // MARK: create, init, dealloc
 Sprite* Sprite::createWithTexture(Texture2D *texture)
 {
@@ -626,10 +620,10 @@ void Sprite::updateTransform(void)
             float dx = x1 * cr - y2 * sr2 + x;
             float dy = x1 * sr + y2 * cr2 + y;
 
-            _quad.bl.vertices.set(RENDER_IN_SUBPIXEL(ax), RENDER_IN_SUBPIXEL(ay), _positionZ);
+            _quad.bl.vertices.set(SPRITE_RENDER_IN_SUBPIXEL(ax), SPRITE_RENDER_IN_SUBPIXEL(ay), _positionZ);
-            _quad.br.vertices.set(RENDER_IN_SUBPIXEL(bx), RENDER_IN_SUBPIXEL(by), _positionZ);
+            _quad.br.vertices.set(SPRITE_RENDER_IN_SUBPIXEL(bx), SPRITE_RENDER_IN_SUBPIXEL(by), _positionZ);
-            _quad.tl.vertices.set(RENDER_IN_SUBPIXEL(dx), RENDER_IN_SUBPIXEL(dy), _positionZ);
+            _quad.tl.vertices.set(SPRITE_RENDER_IN_SUBPIXEL(dx), SPRITE_RENDER_IN_SUBPIXEL(dy), _positionZ);
-            _quad.tr.vertices.set(RENDER_IN_SUBPIXEL(cx), RENDER_IN_SUBPIXEL(cy), _positionZ);
+            _quad.tr.vertices.set(SPRITE_RENDER_IN_SUBPIXEL(cx), SPRITE_RENDER_IN_SUBPIXEL(cy), _positionZ);
         }
 
         // MARMALADE CHANGE: ADDED CHECK FOR nullptr, TO PERMIT SPRITES WITH NO BATCH NODE / TEXTURE ATLAS

cocos/2d/CCSprite.h

@@ -47,6 +47,16 @@ class Size;
 class Texture2D;
 struct transformValues_;
 
+#ifdef SPRITE_RENDER_IN_SUBPIXEL
+#undef SPRITE_RENDER_IN_SUBPIXEL
+#endif
+
+#if CC_SPRITEBATCHNODE_RENDER_SUBPIXEL
+#define SPRITE_RENDER_IN_SUBPIXEL
+#else
+#define SPRITE_RENDER_IN_SUBPIXEL(__ARGS__) (ceil(__ARGS__))
+#endif
+
 /**
  * @addtogroup _2d
  * @{

tests/cpp-tests/Classes/LabelTest/LabelTestNew.cpp

@@ -80,6 +80,7 @@ NewLabelTests::NewLabelTests()
     ADD_TEST_CASE(LabelIssue11699Test);
     ADD_TEST_CASE(LabelIssue12259Test);
     ADD_TEST_CASE(LabelIssue12409Test);
+    ADD_TEST_CASE(LabelAddChildTest);
 };
 
 LabelTTFAlignmentNew::LabelTTFAlignmentNew()
@@ -2011,3 +2012,26 @@ std::string LabelIssue12409Test::subtitle() const
 {
     return "Testing auto-wrapping without space.";
 }
+
+LabelAddChildTest::LabelAddChildTest()
+{
+    auto center = VisibleRect::center();
+
+    auto label = Label::createWithTTF("Label with child node:", "fonts/arial.ttf", 24);
+    label->setPosition(center.x, center.y);
+    addChild(label);
+
+    auto jump = JumpBy::create(1.0f, Vec2::ZERO, 60, 1);
+    auto jump_4ever = RepeatForever::create(jump);
+    label->runAction(jump_4ever);
+
+    auto spite = Sprite::create("Images/SpookyPeas.png");
+    spite->setAnchorPoint(Vec2::ANCHOR_MIDDLE_LEFT);
+    spite->setPosition(label->getContentSize().width, label->getContentSize().height/2);
+    label->addChild(spite);
+}
+
+std::string LabelAddChildTest::title() const
+{
+    return "Label support add child nodes";
+}

tests/cpp-tests/Classes/LabelTest/LabelTestNew.h

@@ -609,4 +609,14 @@ public:
     virtual std::string subtitle() const override;
 };
 
+class LabelAddChildTest : public AtlasDemoNew
+{
+public:
+    CREATE_FUNC(LabelAddChildTest);
+
+    LabelAddChildTest();
+
+    virtual std::string title() const override;
+};
+
 #endif