iOS如何實現貝塞爾曲線畫哆啦A夢

小編給大家分享一下iOS如何實現貝塞爾曲線畫哆啦A夢，希望大家閱讀完這篇文章之后都有所收獲，下面讓我們一起去探討吧！

看到這張圖，是不是覺得挺萌的，那是如何實現的呢？在iOS中有一個類叫UIBezierPath（貝塞爾曲線），這兩天研究了一下UIBezierPath和CAShapeLayer，根據別人分享的教程，畫了這個萌萌的哆啦A夢。

UIBezierPath： UIBezierPath是在 UIKit 中的一個類，繼承于NSObject,可以創建基于矢量的路徑.此類是Core Graphics框架關于path的一個OC封裝。使用此類可以定義常見的圓形、多邊形等形狀 。我們使用直線、弧（arc）來創建復雜的曲線形狀。每一個直線段或者曲線段的結束的地方是下一個的開始的地方。每一個連接的直線或者曲線段的集合成為subpath。一個UIBezierPath對象定義一個完整的路徑包括一個或者多個subpaths。

CAShapeLayer： 繼承于CALayer。 每個CAShapeLayer對象都代表著將要被渲染到屏幕上的一個任意的形狀(shape)。具體的形狀由其path(類型為CGPathRef)屬性指定。 普通的CALayer是矩形，所以需要frame屬性。CAShapeLayer它本身沒有形狀，它的形狀來源于其屬性path 。CAShapeLayer有不同于CALayer的屬性，它從CALayer繼承而來的屬性在繪制時是不起作用的。

基本用法：

畫圓弧： + (instancetype)bezierPathWithArcCenter:(CGPoint)center radius:(CGFloat)radius startAngle:(CGFloat)startAngle endAngle:(CGFloat)endAngle clockwise:(BOOL)clockwise;

1. center表示圓心

2. radius表示半徑

3. startAngle表示開始角度

4. endAngle表示結束角度

5. clockwise表示是否是順時針方向

畫二元曲線和三元曲線，一般和moveToPoint配合使用。

1. 二元曲線：- (void)addQuadCurveToPoint:(CGPoint)endPoint controlPoint:(CGPoint)controlPoint

2. 三元曲線：- (void)addCurveToPoint:(CGPoint)endPoint controlPoint1:(CGPoint)controlPoint1 controlPoint2:(CGPoint)controlPoint2
   

其中 endPoint表示:曲線的終點 ；controlPoint表示:畫曲線的基準點

知道基本畫法后我們就可以畫哆啦A夢了。

1、先畫頭部。先畫一個圓。

//  確定頭部所在的圓心
  CGFloat headCornerRadius=80;
  CGFloat arcCenterX=self.view.frame.size.width/2;
  CGFloat arcCenterY= 120+headCornerRadius;


  //畫頭部
  CAShapeLayer *headLayer=[[CAShapeLayer alloc] init];
  UIBezierPath *headPath=[UIBezierPath bezierPathWithRoundedRect:CGRectMake(self.view.frame.size.width/2-headCornerRadius, 120, headCornerRadius*2, headCornerRadius*2) cornerRadius:headCornerRadius];
  [self setLayer:headLayer path:headPath];

2、畫臉部。畫一個比頭部小點的圓，與頭部圓的底部內切。

 //臉
  CAShapeLayer *faceLayer=[CAShapeLayer layer];
  UIBezierPath *facePath=[UIBezierPath bezierPathWithArcCenter:CGPointMake(self.view.frame.size.width/2, 120+headCornerRadius+10) radius:70 startAngle:M_PI endAngle:3*M_PI clockwise:YES];
  [self setLayer:faceLayer path:facePath];

3、畫眼部

  //左眼
  CAShapeLayer *leftEyeLayer = [CAShapeLayer layer];
  UIBezierPath *leftEyePath = [UIBezierPath bezierPath];
  [leftEyePath moveToPoint:CGPointMake(arcCenterX-30, arcCenterY-25)];
  [leftEyePath addQuadCurveToPoint:CGPointMake(arcCenterX-15, arcCenterY-45) controlPoint:CGPointMake(arcCenterX-30, arcCenterY-45)];
  [leftEyePath addQuadCurveToPoint:CGPointMake(arcCenterX, arcCenterY-25) controlPoint:CGPointMake(arcCenterX, arcCenterY-45)];
  [leftEyePath addQuadCurveToPoint:CGPointMake(arcCenterX-15, arcCenterY-5) controlPoint:CGPointMake(arcCenterX, arcCenterY-5)];
  [leftEyePath addQuadCurveToPoint:CGPointMake(arcCenterX-30, arcCenterY-25) controlPoint:CGPointMake(arcCenterX-30, arcCenterY-5)];
  [self setLayer:leftEyeLayer path:leftEyePath];

  //左眼珠
  CAShapeLayer *leftEyeballLayer = [CAShapeLayer layer];
  UIBezierPath *leftEyeballPath = [UIBezierPath bezierPathWithArcCenter:CGPointMake(arcCenterX-5, arcCenterY-30) radius:2.5 startAngle:0 endAngle:2*M_PI clockwise:YES];
  [self setLayer:leftEyeballLayer path:leftEyeballPath ];

  //右眼
  CAShapeLayer *rightEyeLayer = [CAShapeLayer layer];
  UIBezierPath *rightEyePath = [UIBezierPath bezierPath];
  [rightEyePath moveToPoint:CGPointMake(arcCenterX, arcCenterY-25)];
  [rightEyePath addQuadCurveToPoint:CGPointMake(arcCenterX+15, arcCenterY-45) controlPoint:CGPointMake(arcCenterX, arcCenterY-45)];
  [rightEyePath addQuadCurveToPoint:CGPointMake(arcCenterX+30, arcCenterY-25) controlPoint:CGPointMake(arcCenterX+30, arcCenterY-45)];
  [rightEyePath addQuadCurveToPoint:CGPointMake(arcCenterX+15, arcCenterY-5) controlPoint:CGPointMake(arcCenterX+30, arcCenterY-5)];
  [rightEyePath addQuadCurveToPoint:CGPointMake(arcCenterX, arcCenterY-25) controlPoint:CGPointMake(arcCenterX, arcCenterY-5)];
  [self setLayer:rightEyeLayer path:rightEyePath ];

  //右眼珠
  CAShapeLayer *rightEyeballLayer = [CAShapeLayer layer];
  UIBezierPath *rightEyeballPath = [UIBezierPath bezierPathWithArcCenter:CGPointMake(arcCenterX+5, arcCenterY-30) radius:2.5 startAngle:0 endAngle:2*M_PI clockwise:YES];
  [self setLayer:rightEyeballLayer path:rightEyeballPath];

4、畫鼻子、嘴巴、胡須

  //鼻子
  CAShapeLayer *noseLayer = [CAShapeLayer layer];
  UIBezierPath *nosePath = [UIBezierPath bezierPathWithArcCenter:CGPointMake(arcCenterX, arcCenterY) radius:10 startAngle:0 endAngle:2*M_PI clockwise:YES];
  [self setLayer:noseLayer path:nosePath ];

  //鼻子光暈
  CAShapeLayer *noseHaloLayer = [CAShapeLayer layer];
  UIBezierPath *noseHaloPath = [UIBezierPath bezierPathWithArcCenter:CGPointMake(arcCenterX-4, arcCenterY-5) radius:2.5 startAngle:0 endAngle:2*M_PI clockwise:YES];
  [self setLayer:noseHaloLayer path:noseHaloPath ];

  //嘴巴
  CAShapeLayer *mouthLayer = [CAShapeLayer layer];
  UIBezierPath *mouthPath = [UIBezierPath bezierPath];
  [mouthPath moveToPoint:CGPointMake(arcCenterX-60, arcCenterY+25)];
  [mouthPath addQuadCurveToPoint:CGPointMake(arcCenterX+60, arcCenterY+25) controlPoint:CGPointMake(arcCenterX, arcCenterY+90)];
  [self setLayer:mouthLayer path:mouthPath];

  CAShapeLayer *mouthLayer1 = [CAShapeLayer layer];
  UIBezierPath *mouthPath2 = [UIBezierPath bezierPath];
  [mouthPath2 moveToPoint:CGPointMake(arcCenterX, arcCenterY+10)];
  [mouthPath2 addLineToPoint:CGPointMake(arcCenterX, arcCenterY+55)];
  [self setLayer:mouthLayer1 path:mouthPath2];

  //胡須
  [self addBeardFromPoint:CGPointMake(arcCenterX-58, arcCenterY-5) toPoint:CGPointMake(arcCenterX-15, arcCenterY+10) ];
  [self addBeardFromPoint:CGPointMake(arcCenterX-68, arcCenterY+15) toPoint:CGPointMake(arcCenterX-15, arcCenterY+20) ];
  [self addBeardFromPoint:CGPointMake(arcCenterX-61, arcCenterY+45) toPoint:CGPointMake(arcCenterX-15, arcCenterY+30) ];
  [self addBeardFromPoint:CGPointMake(arcCenterX+58, arcCenterY-5) toPoint:CGPointMake(arcCenterX+15, arcCenterY+10) ];
  [self addBeardFromPoint:CGPointMake(arcCenterX+68, arcCenterY+15) toPoint:CGPointMake(arcCenterX+15, arcCenterY+20) ];
  [self addBeardFromPoint:CGPointMake(arcCenterX+61, arcCenterY+45) toPoint:CGPointMake(arcCenterX+15, arcCenterY+30) ];

5、畫左手部分

 //左手
  CAShapeLayer *leftHandLayer = [CAShapeLayer layer];
  UIBezierPath *leftHandPath = [UIBezierPath bezierPathWithArcCenter:CGPointMake(arcCenterX-95, arcCenterY+110) radius:20 startAngle:0 endAngle:2*M_PI clockwise:YES];
  [self setLayer:leftHandLayer path:leftHandPath ];

  //左胳膊
  CGFloat distanceXToArcCenter = 80*cos(M_PI_2*4/9);
  CGFloat distanceYToArcCenter = 80*sin(M_PI_2*4/9);
  CAShapeLayer *leftArmLayer = [CAShapeLayer layer];
  UIBezierPath *leftArmPath = [UIBezierPath bezierPath];
  [leftArmPath moveToPoint:CGPointMake(arcCenterX-distanceXToArcCenter, arcCenterY+distanceYToArcCenter)];
  [leftArmPath addLineToPoint:CGPointMake(arcCenterX-95, arcCenterY+90)];
  [leftArmPath addQuadCurveToPoint:CGPointMake(arcCenterX-75, arcCenterY+110) controlPoint:CGPointMake(arcCenterX-92, arcCenterY+107)];
  [leftArmPath addLineToPoint:CGPointMake(arcCenterX-distanceXToArcCenter+1.5, arcCenterY+95)];
  [self setLayer:leftArmLayer path:leftArmPath ];

6、畫身體部分

//圍巾
  CAShapeLayer *mufflerLayer = [CAShapeLayer layer];
  UIBezierPath *mufflerPath = [UIBezierPath bezierPath];
  [mufflerPath moveToPoint:CGPointMake(arcCenterX-distanceXToArcCenter, arcCenterY+distanceYToArcCenter)];
  [mufflerPath addQuadCurveToPoint:CGPointMake(arcCenterX+distanceXToArcCenter, arcCenterY+distanceYToArcCenter) controlPoint:CGPointMake(arcCenterX, arcCenterY+109)];
  [mufflerPath addLineToPoint:CGPointMake(arcCenterX+distanceXToArcCenter+2, arcCenterY+distanceYToArcCenter+7)];
  [mufflerPath addQuadCurveToPoint:CGPointMake(arcCenterX-distanceXToArcCenter-4, arcCenterY+distanceYToArcCenter+5) controlPoint:CGPointMake(arcCenterX, arcCenterY+115)];
  [mufflerPath addLineToPoint:CGPointMake(arcCenterX-distanceXToArcCenter, arcCenterY+distanceYToArcCenter)];
  [self setLayer:mufflerLayer path:mufflerPath ];

  //身體
  CAShapeLayer *bodyLayer = [CAShapeLayer layer];
  UIBezierPath *bodyPath = [UIBezierPath bezierPath];
  [bodyPath moveToPoint:CGPointMake(arcCenterX-distanceXToArcCenter, arcCenterY+distanceYToArcCenter+7)];
  [bodyPath addQuadCurveToPoint:CGPointMake(arcCenterX-distanceXToArcCenter+5, arcCenterY+150) controlPoint:CGPointMake(arcCenterX-distanceXToArcCenter+2, arcCenterY+140)];
  [bodyPath addQuadCurveToPoint:CGPointMake(arcCenterX-distanceXToArcCenter+3, arcCenterY+170) controlPoint:CGPointMake(arcCenterX-distanceXToArcCenter, arcCenterY+160)];
  [bodyPath addQuadCurveToPoint:CGPointMake(arcCenterX-8, arcCenterY+170) controlPoint:CGPointMake(arcCenterX-(distanceXToArcCenter+5)/2, arcCenterY+175)];
  [bodyPath addQuadCurveToPoint:CGPointMake(arcCenterX+8, arcCenterY+170) controlPoint:CGPointMake(arcCenterX, arcCenterY+155)];
  [bodyPath addQuadCurveToPoint:CGPointMake(arcCenterX+distanceXToArcCenter-3, arcCenterY+170) controlPoint:CGPointMake(arcCenterX+(distanceXToArcCenter+5)/2, arcCenterY+175)];
  [bodyPath addQuadCurveToPoint:CGPointMake(arcCenterX+distanceXToArcCenter-5, arcCenterY+150) controlPoint:CGPointMake(arcCenterX+distanceXToArcCenter-2, arcCenterY+160)];
  [bodyPath addQuadCurveToPoint:CGPointMake(arcCenterX+distanceXToArcCenter, arcCenterY+distanceYToArcCenter+8) controlPoint:CGPointMake(arcCenterX+distanceXToArcCenter-2, arcCenterY+140)];
  [bodyPath addQuadCurveToPoint:CGPointMake(arcCenterX-distanceXToArcCenter, arcCenterY+distanceYToArcCenter+7) controlPoint:CGPointMake(arcCenterX, arcCenterY+115)];
  [self setLayer:bodyLayer path:bodyPath ];


  //左腳
  CAShapeLayer *leftFootLayer = [CAShapeLayer layer];
  UIBezierPath *leftFootPath = [UIBezierPath bezierPath];
  [leftFootPath moveToPoint:CGPointMake(arcCenterX-distanceXToArcCenter+3, arcCenterY+170)];
  [leftFootPath addQuadCurveToPoint:CGPointMake(arcCenterX-distanceXToArcCenter+3, arcCenterY+195) controlPoint:CGPointMake(arcCenterX-distanceXToArcCenter-20, arcCenterY+185)];
  [leftFootPath addQuadCurveToPoint:CGPointMake(arcCenterX-13, arcCenterY+195) controlPoint:CGPointMake(arcCenterX-(distanceXToArcCenter+10)/2, arcCenterY+200)];
  [leftFootPath addQuadCurveToPoint:CGPointMake(arcCenterX-10, arcCenterY+170) controlPoint:CGPointMake(arcCenterX+8, arcCenterY+187)];
  [self setLayer:leftFootLayer path:leftFootPath ];


  //右腳
  CAShapeLayer *rightFootLayer = [CAShapeLayer layer];
  UIBezierPath *rightFootPath = [UIBezierPath bezierPath];
  [rightFootPath moveToPoint:CGPointMake(arcCenterX+10, arcCenterY+170)];
  [rightFootPath addQuadCurveToPoint:CGPointMake(arcCenterX+15, arcCenterY+195) controlPoint:CGPointMake(arcCenterX-12, arcCenterY+185)];
  [rightFootPath addQuadCurveToPoint:CGPointMake(arcCenterX+distanceXToArcCenter-5, arcCenterY+195) controlPoint:CGPointMake(arcCenterX+(distanceXToArcCenter+20)/2, arcCenterY+200)];
  [rightFootPath addQuadCurveToPoint:CGPointMake(arcCenterX+distanceXToArcCenter-3, arcCenterY+170) controlPoint:CGPointMake(arcCenterX+distanceXToArcCenter+18, arcCenterY+185)];
  [self setLayer:rightFootLayer path:rightFootPath];

  //肚子
  CAShapeLayer *bellyLayer = [CAShapeLayer layer];
  UIBezierPath *bellyPath = [UIBezierPath bezierPath];
  [bellyPath moveToPoint:CGPointMake(arcCenterX-30, arcCenterY+80)];
  [bellyPath addCurveToPoint:CGPointMake(arcCenterX-30, arcCenterY+150) controlPoint1:CGPointMake(arcCenterX-65, arcCenterY+95) controlPoint2:CGPointMake(arcCenterX-60, arcCenterY+140)];
  [bellyPath addQuadCurveToPoint:CGPointMake(arcCenterX+30, arcCenterY+150) controlPoint:CGPointMake(arcCenterX, arcCenterY+160)];
  [bellyPath addCurveToPoint:CGPointMake(arcCenterX+30, arcCenterY+80) controlPoint1:CGPointMake(arcCenterX+60, arcCenterY+140) controlPoint2:CGPointMake(arcCenterX+65, arcCenterY+95)];
  [bellyPath addQuadCurveToPoint:CGPointMake(arcCenterX-30, arcCenterY+80) controlPoint:CGPointMake(arcCenterX, arcCenterY+92)];
  [self setLayer:bellyLayer path:bellyPath ];

  //鈴鐺
  CAShapeLayer *bellLayer = [CAShapeLayer layer];
  UIBezierPath *bellPath = [UIBezierPath bezierPathWithArcCenter:CGPointMake(arcCenterX, arcCenterY+97) radius:15 startAngle:0 endAngle:2*M_PI clockwise:YES];
  [self setLayer:bellLayer path:bellPath ];


  //鈴鐺上的線
  CAShapeLayer *bellLineLayer = [CAShapeLayer layer];
  UIBezierPath *BellLinePath = [UIBezierPath bezierPath];
  [BellLinePath moveToPoint:CGPointMake(arcCenterX-(sqrt(pow(15.0, 2)-pow(5.0, 2))), arcCenterY+92)];
  [BellLinePath addLineToPoint:CGPointMake(arcCenterX+(sqrt(pow(15.0, 2)-pow(5.0, 2))), arcCenterY+92)];
  [BellLinePath moveToPoint:CGPointMake(arcCenterX+(sqrt(pow(15.0, 2)-pow(2.0, 2))), arcCenterY+95)];
  [BellLinePath addLineToPoint:CGPointMake(arcCenterX-(sqrt(pow(15.0, 2)-pow(2.0, 2))), arcCenterY+95)];
  [self setLayer:bellLineLayer path:BellLinePath ];


  //鈴鐺上的小圓點
  CAShapeLayer *bellCirLayer = [CAShapeLayer layer];
  UIBezierPath *bellCirPath = [UIBezierPath bezierPathWithArcCenter:CGPointMake(arcCenterX, arcCenterY+102) radius:2.5 startAngle:0 endAngle:2*M_PI clockwise:YES];
  [bellCirPath moveToPoint:CGPointMake(arcCenterX, arcCenterY+104.5)];
  [bellCirPath addLineToPoint:CGPointMake(arcCenterX, arcCenterY+112)];
  [self setLayer:bellCirLayer path:bellCirPath ];

  //口袋
  CAShapeLayer *bagLayer = [CAShapeLayer layer];
  UIBezierPath *bagPath = [UIBezierPath bezierPath];
  [bagPath moveToPoint:CGPointMake(arcCenterX-40, arcCenterY+112)];
  [bagPath addQuadCurveToPoint:CGPointMake(arcCenterX+40, arcCenterY+112) controlPoint:CGPointMake(arcCenterX, arcCenterY+120)];
  [bagPath addCurveToPoint:CGPointMake(arcCenterX-40, arcCenterY+112) controlPoint1:CGPointMake(arcCenterX+28, arcCenterY+160) controlPoint2:CGPointMake(arcCenterX-28, arcCenterY+160)];
  [self setLayer:bagLayer path:bagPath ];

7、畫右手部分

  //右手
  CAShapeLayer *rightHandLayer = [CAShapeLayer layer];
  UIBezierPath *rightHandPath = [UIBezierPath bezierPathWithArcCenter:CGPointMake(arcCenterX+85*cos(27/180.0*M_PI), arcCenterY-85*sin(27/180.0*M_PI)) radius:20 startAngle:0 endAngle:2*M_PI clockwise:YES];
  [self setLayer:rightHandLayer path:rightHandPath ];


  //右胳膊
  CAShapeLayer *rightArmLayer = [CAShapeLayer layer];
  UIBezierPath *rightArmPath = [UIBezierPath bezierPath];
  [rightArmPath moveToPoint:CGPointMake(arcCenterX+80*cos(13/180.0*M_PI), arcCenterY-80*sin(13/180.0*M_PI))];
  [rightArmPath addQuadCurveToPoint:CGPointMake(arcCenterX+distanceXToArcCenter, arcCenterY+distanceYToArcCenter) controlPoint:CGPointMake(arcCenterX+80*cos(13/180.0*M_PI)+9, arcCenterY+20)];
  [rightArmPath addLineToPoint:CGPointMake(arcCenterX+distanceXToArcCenter, arcCenterY+distanceYToArcCenter+25)];
  [rightArmPath addQuadCurveToPoint:CGPointMake(arcCenterX+93*cos(15/180.0*M_PI), arcCenterY-93*sin(15/180.0*M_PI)) controlPoint:CGPointMake(arcCenterX+90*cos(13/180.0*M_PI)+15, arcCenterY+25)];
  [rightArmPath addQuadCurveToPoint:CGPointMake(arcCenterX+80*cos(13/180.0*M_PI), arcCenterY-80*sin(13/180.0*M_PI)) controlPoint:CGPointMake(arcCenterX+80*cos(13/180.0*M_PI)+5, arcCenterY-93*sin(15/180.0*M_PI)+5)];
  [self setLayer:rightArmLayer path:rightArmPath];

  UILabel *label = [[UILabel alloc] initWithFrame:CGRectMake(self.view.frame.size.width/2+90, 120, 70, 30)];
  label.textAlignment = NSTextAlignmentCenter;
  label.textColor = [UIColor colorWithRed:21/255.0 green:159/255.0 blue:237/255.0 alpha:1];
  label.text = @"Hello";
  label.font = [UIFont fontWithName:@"Chalkduster" size:20];
  [self.view addSubview:label];

  CABasicAnimation *animation = [CABasicAnimation animationWithKeyPath:@"transform.scale"];
  animation.fromValue = @(0);
  animation.toValue = @(1);
  animation.duration = 0.5f;
  [label.layer addAnimation:animation forKey:nil];

8、給各個部位上顏色

 //上色
  faceLayer.fillColor = [UIColor whiteColor].CGColor;
  leftEyeLayer.fillColor = [UIColor whiteColor].CGColor;
  rightEyeLayer.fillColor = [UIColor whiteColor].CGColor;
  leftEyeBallLayer.fillColor = [UIColor blackColor].CGColor;
  rightEyeBallLayer.fillColor = [UIColor blackColor].CGColor;
  noseLayer.fillColor = [UIColor redColor].CGColor;
  noseHaloLayer.fillColor = [UIColor whiteColor].CGColor;
  headLayer.fillColor = [UIColor colorWithRed:21/255.0 green:159/255.0 blue:237/255.0 alpha:1].CGColor;
  leftArmLayer.fillColor = [UIColor colorWithRed:21/255.0 green:159/255.0 blue:237/255.0 alpha:1].CGColor;
  leftHandLayer.fillColor = [UIColor whiteColor].CGColor;
  mufflerLayer.fillColor = [UIColor redColor].CGColor;
  bellyLayer.fillColor = [UIColor whiteColor].CGColor;
  bellLayer.fillColor = [UIColor yellowColor].CGColor;
  bodyLayer.fillColor = [UIColor colorWithRed:21/255.0 green:159/255.0 blue:237/255.0 alpha:1].CGColor;
  rightHandLayer .fillColor=[UIColor whiteColor].CGColor ;
  rightArmLayer .fillColor=[UIColor colorWithRed:21/255.0 green:159/255.0 blue:237/255.0 alpha:1] .CGColor;

這樣，一個簡單的哆啦A夢就實現了。

文中只展示了重要部分的代碼，如果有需要，可以看完整的demo，同時demo里面也展示了UIBezierPath和CAShapeLayer基本的畫圖方法。

看完了這篇文章，相信你對“iOS如何實現貝塞爾曲線畫哆啦A夢”有了一定的了解，如果想了解更多相關知識，歡迎關注億速云行業資訊頻道，感謝各位的閱讀！