1. ARKit點(diǎn)擊屏幕增加文字
2. ARKit點(diǎn)擊屏幕增加3D模型
3. ARKit檢測(cè)到平面自動(dòng)增加3D模型
4. QuickLook的最簡(jiǎn)單使用
5. ARKit人臉貼圖
6. ARKit微笑檢測(cè)
7. ARKit皺眉檢測(cè)
8. ARKit人臉參數(shù)BlendShapes詳解
9. demo

1. ARKit點(diǎn)擊屏幕增加文字

1.點(diǎn)擊屏幕增加文字.gif

• command+shift+n新建一個(gè)項(xiàng)目，然后選擇Augmented Reality App
  

• 在Content Technology中選擇SpriteKit即可
  

• 控制文字距離相機(jī)的距離(改變這個(gè)Z感受一下變化)

matrix_float4x4 translation = matrix_identity_float4x4;
translation.columns[3].z = -1;

2. ARKit點(diǎn)擊屏幕增加3D模型

2.點(diǎn)擊屏幕增加3D模型.gif

2.1 畫面捕捉

主要就是三個(gè)類：

• ARSCNView: 畫面顯示
• ARConfiguration: 捕捉畫面
  • ARWorldTrackingConfiguration:后置攝像頭
  • ARFaceTrackingConfiguration：前置攝像頭,會(huì)實(shí)時(shí)監(jiān)測(cè)面部表情特征
• ARSession:數(shù)據(jù)中轉(zhuǎn)

在viewDidLoad的時(shí)候初始化資源

self.arSCNView = [[ARSCNView alloc] initWithFrame:self.view.bounds options:nil];
    self.arSCNView.session = [[ARSession alloc] init];
    // 1. 創(chuàng)建世界追蹤配置，需要支持A9芯片也就是iPhone6S以上
    self.arWordTrackingConfiguration = [[ARWorldTrackingConfiguration alloc] init];
    // 2. 設(shè)置追蹤方向,追蹤平面
    self.arWordTrackingConfiguration.planeDetection = ARPlaneDetectionHorizontal;
    self.arWordTrackingConfiguration.lightEstimationEnabled = YES;

在viewDidAppear時(shí)讓session開(kāi)始工作

[self.arSession runWithConfiguration:self.arWordTrackingConfiguration]

2.2 點(diǎn)擊增加3D圖像

當(dāng)點(diǎn)擊屏幕的時(shí)候加載一個(gè)scn文件并且作為childNode添加到self.arSCNView.scene.rootNode

- (void)touchesBegan:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event {
    // 1. 使用場(chǎng)景加載scn文件
    SCNScene *scene = [SCNScene sceneNamed:@"art.scnassets/ship.scn"];
    
    SCNNode *shipNode = scene.rootNode.childNodes.firstObject;
    shipNode.position = SCNVector3Make(0, -1, -1);
    
    [self.arSCNView.scene.rootNode addChildNode:shipNode];
}

3. ARKit檢測(cè)到平面自動(dòng)增加3D模型

3.檢測(cè)到平面增加3D模型.gif

#pragma mark - ARSCNViewDelegate
// 添加節(jié)點(diǎn)的時(shí)候調(diào)用(當(dāng)開(kāi)啟平地捕捉模式之后，如果捕捉到平地，ARKit會(huì)自動(dòng)添加一個(gè)平地節(jié)點(diǎn))
- (void)renderer:(id<SCNSceneRenderer>)renderer didAddNode:(SCNNode *)node forAnchor:(ARAnchor *)anchor {
    
    if (![anchor isMemberOfClass:[ARPlaneAnchor class]]) return;
    
    // 添加一個(gè)3D平面模型，ARKit只有捕捉能力，錨點(diǎn)只是一個(gè)空間位置，想更加清楚看到這個(gè)空間，我們需要給控件添加一個(gè)平地的3D模型來(lái)渲染它
    // 1. 獲取捕捉到的平地錨點(diǎn)
    ARPlaneAnchor *planeAnchor = (ARPlaneAnchor *)anchor;
    // 2. 創(chuàng)建一個(gè)3D模型(系統(tǒng)捕捉到的平地是一個(gè)不規(guī)則的大小長(zhǎng)方形，這里筆者q將其變成一個(gè)長(zhǎng)方形，并且對(duì)平地做了一個(gè)縮放效果)
    // 參數(shù)分別是長(zhǎng)、寬、高、圓角
    SCNBox *planeBox = [SCNBox boxWithWidth:planeAnchor.extent.x * 0.3 height:0 length:planeAnchor.extent.x * 0.3 chamferRadius:0];
    // 3. 使用Material渲染3D模型(默認(rèn)模型是白色的)
    planeBox.firstMaterial.diffuse.contents = [UIColor clearColor];
    // 4. 創(chuàng)建一個(gè)基于3D物體模型的節(jié)點(diǎn)
    SCNNode *planeNode = [SCNNode nodeWithGeometry:planeBox];
    // 5. 設(shè)置節(jié)點(diǎn)的位置為捕捉到的平地的錨點(diǎn)的中心位置
    // SceneKit中節(jié)點(diǎn)的位置position是一個(gè)基于3D坐標(biāo)系的矢量坐標(biāo)SCNVector3Make
    planeNode.position = SCNVector3Make(planeAnchor.center.x, 0, planeAnchor.center.z);
    
    [node addChildNode:planeNode];
    
    // 6. 創(chuàng)建一個(gè)花瓶場(chǎng)景
    SCNScene *scene = [SCNScene sceneNamed:@"art.scnassets/vase/vase.scn"];
    // 7. 獲取花瓶節(jié)點(diǎn)
    // 一個(gè)場(chǎng)景有多個(gè)節(jié)點(diǎn)，所有場(chǎng)景有且只有一個(gè)根節(jié)點(diǎn)，其它所有節(jié)點(diǎn)都是根節(jié)點(diǎn)的子節(jié)點(diǎn)
    SCNNode *vaseNode = scene.rootNode.childNodes.firstObject;
    // 8. 設(shè)置花瓶節(jié)點(diǎn)的位置為捕捉到的平地的位置，如果不設(shè)置，則默認(rèn)為原點(diǎn)位置也就是相機(jī)位置
    vaseNode.position = SCNVector3Make(planeAnchor.center.x, 0, planeAnchor.center.z);
    // 9. 將花瓶節(jié)點(diǎn)添加到屏幕中
    // !!!!FBI WARNING: 花瓶節(jié)點(diǎn)是添加到代理捕捉到的節(jié)點(diǎn)中，而不是AR視圖的根接節(jié)點(diǎn)。
    // 因?yàn)椴蹲降降钠降劐^點(diǎn)是一個(gè)本地坐標(biāo)系，而不是世界坐標(biāo)系
    [node addChildNode:vaseNode];
}

4. QuickLook的最簡(jiǎn)單使用

4.QuickLook簡(jiǎn)單使用.gif

這個(gè)沒(méi)什么好說(shuō)的，直接上代碼

#import "ViewController.h"
#import <QuickLook/QuickLook.h>
#import "WYPreviewItem.h"

@interface ViewController ()<QLPreviewControllerDataSource, QLPreviewControllerDelegate>

@end

@implementation ViewController

- (void)viewDidLoad {
    [super viewDidLoad];
    
}

- (void)touchesBegan:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event {
    QLPreviewController *preVC = [[QLPreviewController alloc] init];
    preVC.dataSource = self;
    preVC.delegate = self;
    
    [self presentViewController:preVC animated:YES completion:nil];
}

#pragma mark - QLPreviewControllerDataSource && QLPreviewControllerDelegate
- (NSInteger)numberOfPreviewItemsInPreviewController:(QLPreviewController *)controller {
    return 1;
}

- (id<QLPreviewItem>)previewController:(QLPreviewController *)controller previewItemAtIndex:(NSInteger)index {
    
    return [[NSBundle mainBundle] URLForResource:@"plantpot.usdz" withExtension:nil];
}

- (UIImage *)previewController:(QLPreviewController *)controller transitionImageForPreviewItem:(id<QLPreviewItem>)item contentRect:(CGRect *)contentRect {
    
    CGRect rect = CGRectMake(100, 200, 300, 300);
    contentRect = &rect;
    
    return [UIImage imageNamed:@"wy.jpeg"];
}

5. ARKit人臉貼圖

5.人臉貼圖.gif

設(shè)置session的configuration為ARFaceTrackingConfiguration,然后在ARSCNView的代理renderer:willUpdateNode:forAnchor中增加一個(gè)SCNNode核心代碼如下：

• 創(chuàng)建SCNNode
  • 試試看設(shè)置fillMesh為YES會(huì)怎么樣
  • 試試看設(shè)置masterial.diffuse.contents為一個(gè)顏色會(huì)怎么樣

- (SCNNode *)textureMaskNode {
    if (!_textureMaskNode) {
        
        id<MTLDevice> device = self.arSCNView.device;
        ARSCNFaceGeometry *geometry = [ARSCNFaceGeometry faceGeometryWithDevice:device fillMesh:NO];
        SCNMaterial *material = geometry.firstMaterial;
        material.fillMode = SCNFillModeFill;
        material.diffuse.contents = [UIImage imageNamed:@"wy.jpg"];
        _textureMaskNode = [SCNNode nodeWithGeometry:geometry];
    }
    _textureMaskNode.name = @"textureMask";
    return _textureMaskNode;
}

• 添加SCNNode并更新人臉特征

- (void)renderer:(id<SCNSceneRenderer>)renderer willUpdateNode:(SCNNode *)node forAnchor:(ARAnchor *)anchor {
    
    if (!anchor || ![anchor isKindOfClass:[ARFaceAnchor class]]) return;
    ARFaceAnchor *faceAnchor = (ARFaceAnchor *)anchor;
    
    if (!_textureMaskNode) {
        [node addChildNode:self.textureMaskNode];
    }
    
    ARSCNFaceGeometry *faceGeometry = (ARSCNFaceGeometry *)self.textureMaskNode.geometry;
    if (faceGeometry && [faceGeometry isKindOfClass:[ARSCNFaceGeometry class]]) {
        [faceGeometry updateFromFaceGeometry:faceAnchor.geometry];
    }
}

6. ARKit微笑檢測(cè)

6.微笑檢測(cè).gif

主要用到了ARBlendShapeLocationMouthSmileLeft和ARBlendShapeLocationMouthSmileRight表示微笑的鍵值
我提供的demo是用于調(diào)試微笑閥值的
核心代碼：

- (void)renderer:(id<SCNSceneRenderer>)renderer didUpdateNode:(SCNNode *)node forAnchor:(ARAnchor *)anchor {
    
    if (!anchor || ![anchor isKindOfClass:[ARFaceAnchor class]]) return;
    
    ARFaceAnchor *faceAnchor = (ARFaceAnchor *)anchor;
    
    NSDictionary *blendShips = faceAnchor.blendShapes;
    CGFloat leftSmile = [blendShips[ARBlendShapeLocationMouthSmileLeft] floatValue];
    CGFloat rightSmile = [blendShips[ARBlendShapeLocationMouthSmileRight] floatValue];
    
    NSLog(@"leftSmile = %f, rightSmile = %f", leftSmile, rightSmile);
    if (leftSmile > self.smileValue && rightSmile > self.smileValue) {
        NSLog(@"檢測(cè)到笑容");
        [self.arSession pause];
        dispatch_async(dispatch_get_main_queue(), ^{
            self.resultLabel.hidden = NO;
        });
    }
}

7. ARKit皺眉檢測(cè)

7.皺眉檢測(cè).gif

我這里用的是眉毛向上的鍵值ARBlendShapeLocationBrowInnerUp
核心代碼：

- (void)renderer:(id<SCNSceneRenderer>)renderer didUpdateNode:(SCNNode *)node forAnchor:(ARAnchor *)anchor {
    
    if (!anchor && ![anchor isKindOfClass:[ARFaceAnchor class]]) return;
    
    ARFaceAnchor *faceAnchor = (ARFaceAnchor *)anchor;
    NSDictionary *blendShapes = faceAnchor.blendShapes;
    NSNumber *browInnerUp = blendShapes[ARBlendShapeLocationBrowInnerUp];
    
    if ([browInnerUp floatValue] > self.browValue) {
        [self.arSession pause];
        dispatch_async(dispatch_get_main_queue(), ^{
            self.resultLabel.hidden = NO;
        });
    }
    
    NSLog(@"browInnerUp = %@", browInnerUp);
}

8. BlendShapes

• 僅在iOS11及以上可用，每個(gè)參數(shù)的詳細(xì)介紹和圖片對(duì)比可以打開(kāi)Xcode->Window->Developer Documentation,然后搜索對(duì)應(yīng)的鍵值即可
• 每個(gè)建對(duì)應(yīng)的值都是0~1的值

• 共51個(gè)表示人臉特征的參數(shù)

  
  

ARBlendShapeLocationMouthClose