CCSize size = CCDirector::sharedDirector()->getWinSize();
//使用屏幕尺寸初始化一个空的渲染纹理对象
CCRenderTexture* texture = CCRenderTexture::create((int)size.width, (int)size.height);
//设置位置
texture->setPosition(ccp(size.width/2, size.height/2));
//开始获取
texture->begin();
//遍历场景节点对象，填充纹理到texure中
CCDirector::sharedDirector()->getRunningScene()->visit();
//结束获取
texture->end();
texture->saveToFile("share.png", kCCImageFormatPNG);
代码应该没毛病吧