我怎样才能在精灵上而不是在精灵后面画东西

Question

我使用 cocos2dx v3.8，并使用覆盖绘制成功绘制了一些东西：

void Box2dManager::draw(Renderer *renderer, const Mat4& transform, uint32_t flags){
    GL::enableVertexAttribs( GL::VERTEX_ATTRIB_FLAG_POSITION );
    Director::getInstance()->pushMatrix(MATRIX_STACK_TYPE::MATRIX_STACK_MODELVIEW);
    box2dWorld->DrawDebugData();
    Director::getInstance()->popMatrix(MATRIX_STACK_TYPE::MATRIX_STACK_MODELVIEW);
//  super::draw(renderer, transform, flags);
}

但它总是在精灵后面。 z-order修改后不能改变

已解决

现在我可以修复 cocos2d v3.x box2d DrawDebugData 问题。我粘贴所有 cocos2dx 解决代码。 v2：（简单，因为v2引擎opengl draw是每个单独的任务）

void Box2dManager::draw(){
    ccGLEnableVertexAttribs( kCCVertexAttribFlag_Position );
    kmGLPushMatrix();
    box2dWorld->DrawDebugData();
    kmGLPopMatrix();
}

v3:(v3 引擎使用 quence 将绘图公共项推送到核心，因此您需要创建一个回调）

void Box2dManager::draw(Renderer *renderer, const Mat4& transform, uint32_t flags){
    super::draw(renderer, transform, _transformUpdated);
    GL::enableVertexAttribs( cocos2d::GL::VERTEX_ATTRIB_FLAG_POSITION );
    Director* director = Director::getInstance();
    CCASSERT(nullptr != director, "Director is null when seting matrix stack");
    director->pushMatrix(MATRIX_STACK_TYPE::MATRIX_STACK_MODELVIEW);
    _modelViewMV = director->getMatrix(MATRIX_STACK_TYPE::MATRIX_STACK_MODELVIEW);
    _customCommand.init(_globalZOrder);
    _customCommand.func = CC_CALLBACK_0(Box2dManager::onDraw, this);
    renderer->addCommand(&_customCommand);
    director->popMatrix(MATRIX_STACK_TYPE::MATRIX_STACK_MODELVIEW);
}

void Box2dManager::onDraw() {
    Director* director = Director::getInstance();
    CCASSERT(nullptr != director, "Director is null when seting matrix stack");
    Mat4 oldMV;
    oldMV = director->getMatrix(MATRIX_STACK_TYPE::MATRIX_STACK_MODELVIEW);
    director->loadMatrix(MATRIX_STACK_TYPE::MATRIX_STACK_MODELVIEW, _modelViewMV);
    box2dWorld->DrawDebugData();
    director->loadMatrix(MATRIX_STACK_TYPE::MATRIX_STACK_MODELVIEW, oldMV);
}

参考： http://discuss.cocos2d-x.org/t/box2d-debug-drawing-for-cocos2d-x-3-0/11912/2 http://blog.csdn.net/zszeng/article/details/50000757

Answer 1

如何使用 DrawNode 并将其添加为子项？如果您要使用您在绘图树上管理的节点，那么维护起来会更容易。

auto myDrawing = DrawNode::create();
myDrawing::drawRect(p1, p2, p3, Color4F(255, 255, 0, 255));
myDrawing::setLineWidth(2)
this->addChild(myDrawing);

Answer 2

现在我可以修复 cocos2d v3.x box2d DrawDebugData 问题。然后我粘贴所有 cocos2dx 解决代码。 v2：（简单，因为v2引擎opengl draw是每个单独的任务）

void Box2dManager::draw(){
    ccGLEnableVertexAttribs( kCCVertexAttribFlag_Position );
    kmGLPushMatrix();
    box2dWorld->DrawDebugData();
    kmGLPopMatrix();
}

v3:(v3 引擎使用 quence 将绘图公共项推送到核心，因此您需要创建一个回调）

void Box2dManager::draw(Renderer *renderer, const Mat4& transform, uint32_t flags){
    super::draw(renderer, transform, _transformUpdated);
    GL::enableVertexAttribs( cocos2d::GL::VERTEX_ATTRIB_FLAG_POSITION );
    Director* director = Director::getInstance();
    CCASSERT(nullptr != director, "Director is null when seting matrix stack");
    director->pushMatrix(MATRIX_STACK_TYPE::MATRIX_STACK_MODELVIEW);
    _modelViewMV = director->getMatrix(MATRIX_STACK_TYPE::MATRIX_STACK_MODELVIEW);
    _customCommand.init(_globalZOrder);
    _customCommand.func = CC_CALLBACK_0(Box2dManager::onDraw, this);
    renderer->addCommand(&_customCommand);
    director->popMatrix(MATRIX_STACK_TYPE::MATRIX_STACK_MODELVIEW);
}

void Box2dManager::onDraw() {
    Director* director = Director::getInstance();
    CCASSERT(nullptr != director, "Director is null when seting matrix stack");
    Mat4 oldMV;
    oldMV = director->getMatrix(MATRIX_STACK_TYPE::MATRIX_STACK_MODELVIEW);
    director->loadMatrix(MATRIX_STACK_TYPE::MATRIX_STACK_MODELVIEW, _modelViewMV);
    box2dWorld->DrawDebugData();
    director->loadMatrix(MATRIX_STACK_TYPE::MATRIX_STACK_MODELVIEW, oldMV);
}

参考： http://discuss.cocos2d-x.org/t/box2d-debug-drawing-for-cocos2d-x-3-0/11912/2 http://blog.csdn.net/zszeng/article/details/50000757

Answer 3

    virtual void draw (cocos2d::Renderer* renderer, const cocos2d::Mat4& transform,uint32_t flags) override;
   cocos2d::CustomCommand _customCmd;
 void   onDraw(const cocos2d::Mat4 &transform, uint32_t flags);



void linedraw:: draw(cocos2d::Renderer* renderer, const cocos2d::Mat4 &transform, uint32_t flags){
        //cocos2d::Layer::draw(renderer, transform, flags);


        _customCmd.init(1);
        _customCmd.func = CC_CALLBACK_0(linedraw::onDraw, this, transform, flags);
        renderer->addCommand(&_customCmd);

    }

        void  linedraw:: onDraw(const cocos2d::Mat4 &transform, uint32_t flags)
        {

            }

我怎样才能在精灵上而不是在精灵后面画东西

How can I draw something on the sprite not behind sprite

draw

box2d

cocos2d-x

cocos2d-x-3.0