cocos2dx 源码学习3 CCConfiguration_app

概述CCConfiguration对一些配置信息进行设置，在源码中是用字典来存储这些信息的，及key/value的方式。CCConfiguration也提供了很多函数来返回这些信息。其次CCConfiguration被设计成了单例。下面看下CCConfiguration的成员： protected: GLint m_nMaxTextureSize; /** OpenGL

CCConfiguration对一些配置信息进行设置，在源码中是用字典来存储这些信息的，及key/value的方式。CCConfiguration也提供了很多函数来返回这些信息。其次CCConfiguration被设计成了单例。下面看下CCConfiguration的成员：

protected:
Glint m_nMaxTextureSize;/**OpenGL最大texture尺寸.*/
Glint m_nMaxModelvIEwStackDepth;/**OpenGL最大ModelvIEwStackDepth.*/
bool m_bSupportsPVRTC;/**是否支持PVRTexture压缩*/
bool m_bSupportsNPOT;/**GPU（图形处理器）是否支持NPOT(NonPowerOfTwo)textures.
bool m_bSupportsBGRA8888;/**是否支持BGRA8888textures.
bool m_bSupportsdiscardFramebuffer;/**是否支持gldiscardFramebufferEXT
bool m_bSupportsShareableVAO;/**是否支持VAOs（的增值运营与服务）
Glint m_nMaxSamplesAllowed;
Glint m_nMaxTextureUnits;/**returnsthemaximum（最大）textureunits（单元）
char * m_pGlExtensions;

CCDictionary *m_pValueDict;

可以看出m_pValueDict及是用来保存的字典变量。同时可以看到一些这些私有变量的获取方法以及设置方法：

/** OpenGL Max texture size. */
int getMaxTextureSize(voID) const;

/** OpenGL Max ModelvIEw Stack Depth. */
int getMaxModelvIEwStackDepth(voID) const;

/** returns the maximum texture units*/
int getMaxTextureUnits(voID) const;

/** Whether or not the GPU supports NPOT (Non Power Of Two) textures.
OpenGL ES 2.0 already supports NPOT (iOS).*/

bool supportsNPOT(voID) const;

/** Whether or not PVR Texture Compressed is supported */
bool supportsPVRTC(voID) const;

/** Whether or not BGRA8888 textures are supported.*/
bool supportsBGRA8888(voID) const;

/** Whether or not gldiscardFramebufferEXT is supported*/
bool supportsdiscardFramebuffer(voID) const;

/** Whether or not shareable VAOs are supported.*/
bool supportsShareableVAO(voID) const;

/** returns whether or not an OpenGL is supported */
bool checkForGLExtension(const std::string &searchname) const;

/** returns the value of a given key as a string.If the key is not found,it will return the default value */
const char* getCString( const char *key,const char *default_value=NulL ) const;

/** returns the value of a given key as a boolean.If the key is not found,it will return the default value */
bool getBool( const char *key,bool default_value=false ) const;

/** returns the value of a given key as a double.If the key is not found,it will return the default value */
double getNumber( const char *key,double default_value=0.0 ) const;

/** returns the value of a given key as a double */
CCObject * getobject( const char *key ) const;

/** sets a new key/value pair in the configuration dictionary */
voID setobject( const char *key,CCObject *value );