pineapple ring

ViewController.m

//
//  ViewController.m
//  pineappleRing
//
//  Created by MizushimaYusuke on 2017/08/26.
//  Copyright © 2017 MizushimaYusuke. All rights reserved.
//

#import "ViewController.h"
@import SpriteKit;

@interface ViewController ()
@property (nonatomic, weak) SKScene *scene;
@end

@implementation ViewController

- (void)viewDidLoad {
    [super viewDidLoad];
    [self setupScene];
    [self createPineapples];
}

- (void)setupScene {
    SKView *sv = [[SKView alloc] initWithFrame:self.view.bounds];
    SKScene *s = [SKScene sceneWithSize:sv.frame.size];
    s.backgroundColor = [UIColor colorWithHue:0.4 saturation:0.1 brightness:1 alpha:1];
    [sv presentScene:s];
    [self.view addSubview:sv];
    self.scene = s;
}

- (void)createPineapples {
    for (int i=0; i<18; i++) {
        for (int j=0; j<8; j++) {
            if (arc4random_uniform(10) == 0) {
                continue;
            }
            SKNode *pineapple = [self createPineapple];
            pineapple.position = CGPointMake(i * 50, j * 50);
        }
    }
}

- (SKNode *)createPineapple {
    UIGraphicsBeginImageContextWithOptions(CGSizeMake(40, 40), NO, 0);
    CGContextRef ctx = UIGraphicsGetCurrentContext();
    [[UIColor colorWithHue:0.14 saturation:0.8 brightness:0.95 alpha:1] set];
    CGContextFillEllipseInRect(ctx, CGRectMake(0, 0, 40, 40));
    CGContextTranslateCTM(ctx, 20, 20);
    [[UIColor colorWithHue:0.14 saturation:0.2 brightness:1 alpha:1] set];
    for (int i=0; i<10; i++) {
        float r0 = arc4random_uniform(2);
        float r1 = arc4random_uniform(5) + 4;
        CGContextFillRect(ctx, CGRectMake(10 + r0, -0.5, r1, 1));
        CGContextRotateCTM(ctx, M_PI / 5);
    }
    CGContextSetBlendMode(ctx, kCGBlendModeClear);
    CGContextFillEllipseInRect(ctx, CGRectMake(-8, -8, 16, 16));
    UIImage *img = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();
    
    SKTexture *texture = [SKTexture textureWithImage:img];
    SKSpriteNode *pineapple = [SKSpriteNode spriteNodeWithTexture:texture];
    pineapple.name = @"pineapple";
    pineapple.position = CGPointMake(CGRectGetMidX(self.view.bounds), CGRectGetMidY(self.view.bounds));
    [self.scene addChild:pineapple];
    
    return pineapple;
}

- (void)touchesBegan:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event {
    [self.scene enumerateChildNodesWithName:@"pineapple" usingBlock:^(SKNode * _Nonnull node, BOOL * _Nonnull stop) {
        if (arc4random_uniform(5) == 0) {
            [node runAction:[SKAction rotateByAngle:2.0 * M_PI duration:3.0]];
        }
    }];
}

@end

http://lepetit-prince.net/ios/?p=6593