CCCamera，CCAtlasNode源码解析

源码：

/** * Note:  * Scene creates a default camera. And the default camera mask of Node is 1, therefore it can be seen by the default camera. * During rendering the scene, it draws the objects seen by each camera in the added order except default camera. The default camera is the last one being drawn with. * It's usually a good idea to render 3D objects in a separate camera. * And set the 3d camera flag to CameraFlag::USER1 or anything else except DEFAULT. Dedicate The DEFAULT camera for UI, because it is rendered at last. * You can change the camera order to get different result when depth test is not enabled. * For each camera, transparent 3d sprite is rendered after opaque 3d sprite and other 2d objects. */ /// 场景创建了一个默认的摄像机，默认的摄像机遮挡的节点是1个。因此，它可以被默认的摄像机看到。在场景的渲染期间，按加入的顺序，通过每个摄像机绘制每个对象。 /// 默认的摄像机是最后被沪指的。 ///  在绘制3D对象的时候，是用分离摄像机是一个不错的方法 /// enum class CameraFlag/// 摄像机的标识{    DEFAULT = 1,    USER1 = 1 << 1,    USER2 = 1 << 2,    USER3 = 1 << 3,    USER4 = 1 << 4,    USER5 = 1 << 5,    USER6 = 1 << 6,    USER7 = 1 << 7,    USER8 = 1 << 8,};/*** Defines a camera .*//// 声明一个摄像机class CC_DLL Camera :public Node{    friend class Scene;public:    /**    * The type of camera.    */    enum class Type    {        PERSPECTIVE = 1,        ORTHOGRAPHIC = 2    };public:    /**    * Creates a perspective camera.    *    * @param fieldOfView The field of view for the perspective camera (normally in the range of 40-60 degrees).    * @param aspectRatio The aspect ratio of the camera (normally the width of the viewport divided by the height of the viewport).    * @param nearPlane The near plane distance.    * @param farPlane The far plane distance.    *//// 创建一个透视摄像机    static Camera* createPerspective(float fieldOfView, float aspectRatio, float nearPlane, float farPlane);    /**    * Creates an orthographic camera.    *    * @param zoomX The zoom factor along the X-axis of the orthographic projection (the width of the ortho projection).    * @param zoomY The zoom factor along the Y-axis of the orthographic projection (the height of the ortho projection).    * @param nearPlane The near plane distance.    * @param farPlane The far plane distance.    *//// 创建一个正视摄像机    static Camera* createOrthographic(float zoomX, float zoomY, float nearPlane, float farPlane);    /** create default camera, the camera type depends on Director::getProjection, the depth of the default camera is 0 *//// 创建一个摄像机    static Camera* create();        /**    * Gets the type of camera.    *    * @return The camera type.    *//// 得到摄像机的类型    Camera::Type getType() const { return _type; }    /**get & set Camera flag*//// 得到摄像机的标识    CameraFlag getCameraFlag() const { return (CameraFlag)_cameraFlag; }/// 设置摄像机的标识    void setCameraFlag(CameraFlag flag) { _cameraFlag = (unsigned short)flag; }    /**    * Make Camera looks at target    *    * @param target The target camera is point at    * @param up The up vector, usually it's Y axis    *//// 是摄像机观看某个目标    virtual void lookAt(const Vec3& target, const Vec3& up = Vec3::UNIT_Y);    /**    * Gets the camera's projection matrix.    *    * @return The camera projection matrix.    *//// 得到透视摄像机的矩阵    const Mat4& getProjectionMatrix() const;    /**    * Gets the camera's view matrix.    *    * @return The camera view matrix.    *//// 得到摄像机视窗的矩阵    const Mat4& getViewMatrix() const;    /**get view projection matrix*//// 得到透视摄像机视窗的矩阵    const Mat4& getViewProjectionMatrix() const;        /* convert the specified point of viewport from world-space coordinates into the screen-space coordinates.     *     * @param src The world-space position.     * @return The screen-space position.     */ /// 将视窗坐标，转换为屏幕坐标    Vec2 project(const Vec3& src) const;        /**     * Convert the specified point of viewport from screen-space coordinate into the world-space coordinate.     *     * @param src The screen-space position.     * @return The world-space position.     */ /// 将屏幕坐标转换为世界坐标    Vec3 unproject(const Vec3& src) const;    /**     * Convert the specified point of viewport from screen-space coordinate into the world-space coordinate.     *     * @param viewport The viewport size to use.     * @param src The screen-space position.     * @param dst The world-space position.     */ /// 将屏幕坐标转换为世界坐标    void unproject(const Size& viewport, const Vec3* src, Vec3* dst) const;        /**     * Is this aabb visible in frustum     */ /// aabb在锥形区间中是否可见    bool isVisibleInFrustum(const AABB* aabb) const;        /**     * Get object depth towards camera     */ /// 得到实例在摄像机中的深度    float getDepthInView(const Mat4& transform) const;        /**     * set depth, camera with larger depth is drawn on top of camera with smaller depth, the depth of camera with CameraFlag::DEFAULT is 0, user defined camera is -1 by default     */ /// 设置深度    void setDepth(int depth);        /**     * get depth, camera with larger depth is drawn on top of camera with smaller depth, the depth of camera with CameraFlag::DEFAULT is 0, user defined camera is -1 by default     */ /// 得到深度    int getDepth() const { return _depth; }        //override    virtual void onEnter() override;    virtual void onExit() override;    /**     * Get the visiting camera , the visiting camera shall be set on Scene::render     */ /// 得到当前访问的摄像机    static const Camera* getVisitingCamera() { return _visitingCamera; }    /**     * Get the default camera of the current running scene.     */ /// 得到默认的摄像机    static Camera* getDefaultCamera();CC_CONSTRUCTOR_ACCESS:    Camera();    ~Camera();        /**     * Set the scene,this method shall not be invoke manually     */ /// 设置场景    void setScene(Scene* scene);        /**set additional matrix for the projection matrix, it multiplys mat to projection matrix when called, used by WP8*//// 设置额外的投影    void setAdditionalProjection(const Mat4& mat);        /** init camera */    /// 初始化摄像机bool initDefault();    bool initPerspective(float fieldOfView, float aspectRatio, float nearPlane, float farPlane);    bool initOrthographic(float zoomX, float zoomY, float nearPlane, float farPlane);protected:    Scene* _scene; //Scene camera belongs to    Mat4 _projection;    mutable Mat4 _view;    mutable Mat4 _viewInv;    mutable Mat4 _viewProjection;    Vec3 _up;    Camera::Type _type;    float _fieldOfView;    float _zoom[2];    float _aspectRatio;    float _nearPlane;    float _farPlane;    mutable bool  _viewProjectionDirty;    unsigned short _cameraFlag; // camera flag    mutable Frustum _frustum;   // camera frustum    mutable bool _frustumDirty;    int  _depth;                 //camera depth, the depth of camera with CameraFlag::DEFAULT flag is 0 by default, a camera with larger depth is drawn on top of camera with smaller detph    static Camera* _visitingCamera;        friend class Director;};

源码：

/** @brief AtlasNode is a subclass of Node that implements the RGBAProtocol and TextureProtocol protocol. * It knows how to render a TextureAtlas object. * If you are going to render a TextureAtlas consider subclassing AtlasNode (or a subclass of AtlasNode). * All features from Node are valid, plus the following features: * - opacity and RGB colors. */ /// AtlasNode是一个实现了RGBAProtocol和TextureProtocol的子类 /// 图集节点class CC_DLL AtlasNode : public Node, public TextureProtocol{    public:/** creates a AtlasNode  with an Atlas file the width and height of each item and the quantity of items to render.     *     * @param filename The path of Atlas file.     * @param tileWidth The width of the item.     * @param tileHeight The height of the item.     * @param itemsToRender The quantity of items to render.     */ /// 创建一个图集节点static AtlasNode * create(const std::string& filename, int tileWidth, int tileHeight, int itemsToRender);    /** updates the Atlas (indexed vertex array).    * Shall be overridden in subclasses.    *//// 更新图集节点的值    virtual void updateAtlasValues();        /** Set an buffer manager of the texture vertex. *//// 设置图集节点的纹理    void setTextureAtlas(TextureAtlas* textureAtlas);        /** Return the buffer manager of the texture vertex.      *     * @return Return A TextureAtlas.     */ /// 得到图集节点的纹理    TextureAtlas* getTextureAtlas() const;        void setQuadsToDraw(ssize_t quadsToDraw);    ssize_t getQuadsToDraw() const;        // Overrides    virtual void draw(Renderer *renderer, const Mat4 &transform, uint32_t flags) override;    virtual Texture2D* getTexture() const override;    virtual void setTexture(Texture2D *texture) override;    virtual bool isOpacityModifyRGB() const override;    virtual void setOpacityModifyRGB(bool isOpacityModifyRGB) override;    virtual const Color3B& getColor(void) const override;    virtual void setColor(const Color3B& color) override;    virtual void setOpacity(GLubyte opacity) override;    /**    * @code    * When this function bound into js or lua,the parameter will be changed    * In js: var setBlendFunc(var src, var dst)    * @endcode    * @lua NA    *//// 设置混合函数    virtual void setBlendFunc(const BlendFunc& blendFunc) override;    /**    * @lua NA    *//// 得到混合函数    virtual const BlendFunc& getBlendFunc() const override;CC_CONSTRUCTOR_ACCESS:    AtlasNode();    virtual ~AtlasNode();/// 初始化    /** Initializes an AtlasNode  with an Atlas file the width and height of each item and the quantity of items to render*/    bool initWithTileFile(const std::string& tile, int tileWidth, int tileHeight, int itemsToRender);        /** Initializes an AtlasNode  with a texture the width and height of each item measured in points and the quantity of items to render*/    bool initWithTexture(Texture2D* texture, int tileWidth, int tileHeight, int itemsToRender);protected:    void calculateMaxItems();    void updateBlendFunc();    void updateOpacityModifyRGB();    friend class Director;    void setIgnoreContentScaleFactor(bool bIgnoreContentScaleFactor);    /** Chars per row. */    int    _itemsPerRow;    /** Chars per column. */    int    _itemsPerColumn;    /** Width of each char. */    int    _itemWidth;    /** Height of each char. */    int    _itemHeight;        Color3B    _colorUnmodified;        TextureAtlas* _textureAtlas;    /** Protocol variables. */    bool _isOpacityModifyRGB;    BlendFunc _blendFunc;    /** Quads to draw. */    ssize_t _quadsToDraw;    /** Color uniform. */    GLint    _uniformColor;    /** This varible is only used for LabelAtlas FPS display. So plz don't modify its value. */    bool _ignoreContentScaleFactor;    /** Quad command. */    QuadCommand _quadCommand;private:    CC_DISALLOW_COPY_AND_ASSIGN(AtlasNode);};