c++ - Xcode需要哪些设置才能构建此代码

Question

让我们看一下位于头文件中的这段代码。该项目本身是Objective-C++(。h和.mm文件)。
这看起来像是C++和Objective-C的混合体。根据我的阅读，为了将Objective-C++与Objective-C混合使用，您必须将所有C++内容保留在头文件之外，但是事实并非如此。
该项目构建良好，但是我不能在新项目中复制它(通过复制相同的代码)。
Xcode需要哪些设置才能构建它？已经比较了项目构 build 置，它们是相同的。
错误与Options结构中的内联初始化程序有关。

/*
  This file is part of the Structure SDK.
  Copyright © 2019 Occipital, Inc. All rights reserved.
  http://structure.io
*/

#import <UIKit/UIKit.h>
#import <AVFoundation/AVFoundation.h>

#import <Structure/Structure.h>
#import <Structure/STCaptureSession.h>

#import "CalibrationOverlay.h"
#import "MeshViewController.h"
#import "SettingsPopupView.h"

// See default initialization in: -(void)initializeDynamicOptions
struct DynamicOptions
{
    bool depthAndColorTrackerIsOn;
    bool improvedTrackingIsOn;
    bool highResColoring;
    bool improvedMapperIsOn;
    bool highResMapping;
    STCaptureSessionPreset depthStreamPreset;
};

struct Options
{
    // The initial scanning volume size will be 0.5 x 0.5 x 0.5 meters
    // (X is left-right, Y is up-down, Z is forward-back)
    const GLKVector3 initVolumeSizeInMeters = GLKVector3Make (0.5f, 0.5f, 0.5f);
    
    // The maximum number of keyframes saved in keyFrameManager
    int maxNumKeyFrames = 48;
    
    // Colorizer quality
    STColorizerQuality colorizerQuality = STColorizerHighQuality;
    
    // Take a new keyframe in the rotation difference is higher than 20 degrees.
    float maxKeyFrameRotation = 20.0f * (M_PI / 180.f); // 20 degrees
    
    // Take a new keyframe if the translation difference is higher than 30 cm.
    float maxKeyFrameTranslation = 0.3; // 30cm

    // Threshold to consider that the rotation motion was small enough for a frame to be accepted
    // as a keyframe. This avoids capturing keyframes with strong motion blur / rolling shutter.
    float maxKeyframeRotationSpeedInDegreesPerSecond = 1.f;
    
    // Whether we should use depth aligned to the color viewpoint when Structure Sensor was calibrated.
    // This setting may get overwritten to false if no color camera can be used.
    bool useHardwareRegisteredDepth = false;
    
    // Whether to enable an expensive per-frame depth accuracy refinement.
    // Note: this option requires useHardwareRegisteredDepth to be set to false.
    const bool applyExpensiveCorrectionToDepth = true;
    
    // Whether the colorizer should try harder to preserve appearance of the first keyframe.
    // Recommended for face scans.
    bool prioritizeFirstFrameColor = true;
    
    // Target number of faces of the final textured mesh.
    int colorizerTargetNumFaces = 50000;
    
    // Focus position for the color camera (between 0 and 1). Must remain fixed one depth streaming
    // has started when using hardware registered depth.
    const float lensPosition = 0.75f;
};

...
@interface ViewController : UIViewController <STBackgroundTaskDelegate, MeshViewDelegate, AVCaptureVideoDataOutputSampleBufferDelegate, UIPopoverControllerDelegate, UIGestureRecognizerDelegate, SettingsPopupViewDelegate>
{
...
}
@end

有关错误的一些详细信息:

Answer 1

我假设您只是#include / #import在.mm文件中使用此 header 。
默认的struct字段值是C++ 11的新功能。新项目中的C++标准是否可能设置为C++ 98？
我不确定100％的细节，但是也许某些更复杂的默认值表达式只能在更新版本的C++中使用。因此，我建议您尝试在项目中更改C++标准版本，看看它是否有效果。