Cocos2dx-截屏并設定圖檔尺寸

猴子原創，歡迎轉載。轉載請注明： 轉載自Cocos2D開發網–Cocos2Dev.com，謝謝！

原文位址: http://www.cocos2dev.com/?p=522

前幾天添加微信圖檔分享的時候，發現全屏截圖超出了微信的資料包大小，是以截屏的時候可以考慮縮小尺寸到0.5倍。

下面的截屏代碼：

void LHUtil::screenShoot()
{
    Size visibleSize = Director::getInstance()->getVisibleSize();
    
    //定義一個螢幕大小的渲染紋理
    RenderTexture* renderTexture = RenderTexture::create(visibleSize.width * .5, visibleSize.height * .5, Texture2D::PixelFormat::RGBA8888);

    Scene* curScene = Director::getInstance()->getRunningScene();
    Point ancPos = pCurScene->getAnchorPoint();

    //渲染紋理開始捕捉
    renderTexture->begin();

    // 縮小螢幕截屏區域
    curScene->setScale(.5);
    curScene->setAnchorPoint(cocos2d::Point(0, 0));

    //繪制目前場景
    curScene->visit();

    //結束
    renderTexture->end();

    //儲存png
    renderTexture->saveToFile("screenshoot.png", Image::Format::PNG);

    // 恢複螢幕尺寸
    curScene->setScale(1);
    curScene->setAnchorPoint(ancPos);
    CC_SAFE_DELETE(curScene);
}
           

上面是cocos2dx的擷取截屏的方法。

我順便寫下如何用OC的UIGraphicsBeginImageContext擷取UIView轉化成UIImage.

下面是ios方法：

-(void)screenShot:(CGRect)rect{
    // 開始設定截屏區域
    UIGraphicsBeginImageContextWithOptions(rect.size, YES, 0);
    [[self.view layer] renderInContext:UIGraphicsGetCurrentContext()];
    UIImage *viewImage = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();
    
    // 擷取image，可以根據需要進行尺寸修改
    CGImageRef imageRef = viewImage.CGImage;
    CGImageRef imageRefRect =CGImageCreateWithImageInRect(imageRef, rect);
    UIImage *image = [[UIImage alloc] initWithCGImage:imageRefRect];
    
    // 儲存圖檔到相冊, 這裡會提示使用者授權，不需要儲存的話，可以取消
    UIImageWriteToSavedPhotosAlbum(image, nil, nil, nil);
    
    // 擷取Documents目錄
    NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
    NSString *documentsDirectory = [paths objectAtIndex:0];
    NSString *savedImagePath = [documentsDirectory stringByAppendingPathComponent:@"temScreenShot.png"];
    
    // 儲存image到Documents目錄
    NSData *imageData = UIImagePNGRepresentation(image);
    [imageData writeToFile:savedImagePath atomically:YES];
    CGImageRelease(imageRefRect);
}