RenderTexture 截图无法指定保存路径？

Cocos2d-x
#1 
    //创建渲染纹理  
    auto render = RenderTexture::create(width, height, Texture2D::PixelFormat::RGBA8888);  
    render->setSprite(sprite);  

    //填充纹理  
    render->beginWithClear(0, 0, 0, 0);  
    sprite->visit();  
    render->end();  

    //Image* image=render->newImage(true);
    //image->saveToFile("./Resources/output/" + item.first,true);
    //文件被保存在类似于C:\Users\Administrator\AppData\Local\ProjectName的路径中  
    render->saveToFile("./Resources/output/" + item.first, Image::Format::PNG,true,CC_CALLBACK_2(HelloWorld::saveCallBack,this));

请问这要怎么解决？只允许在win7下运行 ，但是无法指定保存路径。

#2

二楼决解办法:10:

#ifndef VRENDERIMAGE_H
#define VRENDERIMAGE_H
#include “cocos2d.h”
#include “cocostudio/CocoStudio.h”
#include “ui/CocosGUI.h”

USING_NS_CC;
using namespace cocos2d::ui;

class VRenderImage:public RenderTexture
{
public:
VRenderImage(void);
~VRenderImage(void);

static VRenderImage * create(int w, int h, Texture2D::PixelFormat format);

bool saveToImageFile(const std::string& filepath, Image::Format format, bool isRGBA = true, std::function<void (RenderTexture*, const std::string&)> callback = nullptr);

};
#endif

#include “VRenderImage.h”

VRenderImage::VRenderImage(void)
{
}

VRenderImage::~VRenderImage(void)
{
}

VRenderImage * VRenderImage::create(int w, int h, Texture2D::PixelFormat format)
{
VRenderImage *ret = new (std::nothrow) VRenderImage();

if(ret && ret->initWithWidthAndHeight(w, h, format))
{
    ret->autorelease();
    return ret;
}
CC_SAFE_DELETE(ret);
return nullptr;

}

bool VRenderImage::saveToImageFile(const std::string& filepath, Image::Format format, bool isRGBA /= true/, std::function<void (RenderTexture*, const std::string&)> callback /= nullptr/)
{
CCASSERT(format == Image::Format::JPG || format == Image::Format::PNG,
“the image can only be saved as JPG or PNG format”);
if (isRGBA && format == Image::Format::JPG) CCLOG(“RGBA is not supported for JPG format”);

_saveFileCallback = callback;

std::string fullpath = filepath;
_saveToFileCommand.init(_globalZOrder);
_saveToFileCommand.func = CC_CALLBACK_0(VRenderImage::onSaveToFile, this, fullpath, isRGBA);

Director::getInstance()->getRenderer()->addCommand(&_saveToFileCommand);
return true;

}