IOS绘制小黄人，对绘图知识的一个练习

#define kTopX rect.size.width * 0.5
#define kTopRadius 80
#define kTopY 260

//
//  HMView.m
//  004-绘制小黄人
//
//  Created by lujun on 2021/6/11.
//
#import "HMView.h"
@implementation HMView
- (void)drawRect:(CGRect)rect{
    CGContextRef ctx = UIGraphicsGetCurrentContext();
    //画身体
    [self drawBody:rect withContext:ctx];
    [self drawEyes:rect withContext:ctx];
    [self drawMouth:rect withContext:ctx];
    [self drawhair:rect withContext:ctx];
}
-(void)drawhair:(CGRect)rect withContext:(CGContextRef) ctx{
    CGContextMoveToPoint(ctx, kTopX-30, kTopY-kTopRadius-30);
    CGContextAddLineToPoint(ctx, kTopX-20, kTopY-kTopRadius+5 );
    [[UIColor blackColor] set];
    CGContextStrokePath(ctx);
    
    CGContextMoveToPoint(ctx, kTopX-22, kTopY-kTopRadius-30);
    CGContextAddLineToPoint(ctx, kTopX-8, kTopY-kTopRadius+5 );
    [[UIColor blackColor] set];
    CGContextStrokePath(ctx);
    
    CGContextMoveToPoint(ctx, kTopX, kTopY-kTopRadius-30);
    CGContextAddLineToPoint(ctx, kTopX, kTopY-kTopRadius+5 );
    [[UIColor blackColor] set];
    CGContextStrokePath(ctx);
    
    CGContextMoveToPoint(ctx, kTopX+30, kTopY-kTopRadius-30);
    CGContextAddLineToPoint(ctx, kTopX+20, kTopY-kTopRadius+5 );
    [[UIColor blackColor] set];
    
    CGContextMoveToPoint(ctx, kTopX+22, kTopY-kTopRadius-30);
    CGContextAddLineToPoint(ctx, kTopX+8, kTopY-kTopRadius+5 );
    [[UIColor blackColor] set];
    CGContextStrokePath(ctx);
}

-(void)drawMouth:(CGRect)rect withContext:(CGContextRef) ctx{
//贝塞尔曲线
    //控制点
    CGFloat controllerX = kTopX;
    CGFloat controllerY = rect.size.height*0.3 + 50;
    //当前点
    CGFloat marginX = 20;
    CGFloat marginY = 10;
    CGFloat currentX = controllerX-marginX;
    CGFloat currentY = controllerY - marginY;
    CGContextMoveToPoint(ctx, currentX, currentY);
    //结束点
    CGFloat endX = controllerX + marginX;
    CGFloat endY = currentY;
    CGContextAddQuadCurveToPoint(ctx, controllerX, controllerY, endX, endY);
    CGContextSetLineWidth(ctx, 1);
    [[UIColor blackColor] set];
    CGContextStrokePath(ctx);
}

-(void)drawEyes:(CGRect)rect withContext:(CGContextRef) ctx{
    CGFloat startX =  kTopX - kTopRadius;
    CGFloat startY = kTopY;
    CGContextMoveToPoint(ctx, startX, startY);
    CGFloat endX =  kTopX + kTopRadius;
    CGFloat endY =  startY;
    CGContextAddLineToPoint(ctx, endX, endY);
    CGContextSetLineWidth(ctx, 18);
    [[UIColor blackColor] set];
    CGContextStrokePath(ctx);
    //画左边第一支大眼睛
    CGFloat leftRaduis = 30;
    CGFloat leftX = kTopX - leftRaduis;
    CGFloat leftY = kTopY;
    CGContextAddArc(ctx, leftX, leftY, leftRaduis, 0, 2 * M_PI, 0);
    [[UIColor grayColor] set];
    CGContextFillPath(ctx);
    //画右边第一支大眼睛
    CGFloat rightRaduis = 30;
    CGFloat rightX = kTopX + leftRaduis;
    CGFloat rightY = kTopY;
    CGContextAddArc(ctx, rightX, rightY, rightRaduis, 0, 2 * M_PI, 0);
    [[UIColor grayColor] set];
    CGContextFillPath(ctx);
    //画左边二眼睛
    CGFloat leftSmallRaduis = 20;
    CGFloat leftSmallX =  leftX;
    CGFloat leftSmallY = leftY;
    CGContextAddArc(ctx, leftSmallX, leftSmallY, leftSmallRaduis, 0, 2 * M_PI, 0);
    [[UIColor whiteColor] set];
    CGContextFillPath(ctx);
    //画右边二眼睛
    CGFloat rightSmallRaduis = 20;
    CGFloat rightSmallX =  rightX;
    CGFloat rightSmallY = rightY;
    CGContextAddArc(ctx, rightSmallX, rightSmallY, rightSmallRaduis, 0, 2 * M_PI, 0);
    [[UIColor whiteColor] set];
    CGContextFillPath(ctx);
    //画左边三眼睛
    CGFloat leftSsmallRaduis = 8;
    CGFloat leftSsmallX =  leftX +8;
    CGFloat leftSsmallY = leftY;
    CGContextAddArc(ctx, leftSsmallX, leftSsmallY, leftSsmallRaduis, 0, 2 * M_PI, 0);
    [[UIColor colorWithRed:88/255.0 green:23/255.0 blue:9/255.0 alpha:1] set];
    CGContextFillPath(ctx);
    //画右边三眼睛
    CGFloat rightSsmallRaduis = 8;
    CGFloat rightSsmallX =  rightX -8;
    CGFloat rightSsmallY = rightY;
    CGContextAddArc(ctx, rightSsmallX, rightSsmallY, rightSsmallRaduis, 0, 2 * M_PI, 0);
    [[UIColor colorWithRed:88/255.0 green:23/255.0 blue:9/255.0 alpha:1] set];
    CGContextFillPath(ctx);
    //画左边四眼睛
    CGContextAddArc(ctx, leftSsmallX, leftSsmallY, 4, 0, 2 * M_PI, 0);
    [[UIColor blackColor] set];
    CGContextFillPath(ctx);
    //画右边四眼睛
    CGContextAddArc(ctx, rightSsmallX, rightSsmallY, 4, 0, 2 * M_PI, 0);
    [[UIColor blackColor] set];
    CGContextFillPath(ctx);
    //画左边五眼睛，白点
    CGContextAddArc(ctx, leftSsmallX-3, leftSsmallY-3, 2, 0, 2 * M_PI, 0);
    [[UIColor whiteColor] set];
    CGContextFillPath(ctx);
    //画右边五眼睛，白点
    CGContextAddArc(ctx, rightSsmallX-3, rightSsmallY-3, 2, 0, 2 * M_PI, 0);
    [[UIColor whiteColor] set];
    CGContextFillPath(ctx);
}

-(void)drawBody:(CGRect)rect withContext:(CGContextRef) ctx{
    //画上半圆弧
    CGFloat topX=kTopX;
    CGFloat topY = kTopY;
    CGFloat radius = kTopRadius;
    CGContextAddArc(ctx, topX, topY, radius, -M_PI, 0, 0);

    //画下半圆弧
    CGFloat middX = topX + radius;
    CGFloat middY = topY + 120;
    
    CGContextAddLineToPoint(ctx, middX, middY);
    CGFloat bottomRadius = radius;
    CGFloat bottomX = topX;
    CGFloat bottomY = middY;
    CGContextAddArc(ctx, bottomX, bottomY, bottomRadius, 0, M_PI, 0);
    CGContextClosePath(ctx);
    [[UIColor colorWithRed:252/255.0 green:215/255.0 blue:0 alpha:1.0] set];
    CGContextFillPath(ctx);
}
@end

源码在我的主页下面