コップの中からボールがこぼれ落ちるようなiPhoneアプリのサンプルコードを描いてみます。
#import “ViewController.h”
#import <SpriteKit/SpriteKit.h>
@interface GlassScene : SKScene
@end
@implementation GlassScene
– (void)didMoveToView:(SKView *)view
{
self.backgroundColor = [self color:0];
SKLabelNode *l = [SKLabelNode node];
l.text = @”spill”;
l.fontName = @”chalkduster”;
l.fontColor = [[SKColor whiteColor] colorWithAlphaComponent:0.7];
l.position = CGPointMake(160, 40);
[self addChild:l];
self.physicsBody = [SKPhysicsBody bodyWithEdgeLoopFromRect:self.frame];
for (int i=0; i<3; i++) {
SKNode *glass = [self createGlass];
glass.position = CGPointMake(100 + 50 * i, 300 – 100*i);
SKPhysicsJointPin *pin = [SKPhysicsJointPin jointWithBodyA:glass.physicsBody bodyB:self.physicsBody anchor:CGPointMake(glass.position.x + 5,glass.position.y)];
pin.shouldEnableLimits = YES;
pin.upperAngleLimit = 0.4;
pin.lowerAngleLimit = –M_PI/2.0 + 0.1;
[self.physicsWorld addJoint:pin];
}
}
– (SKNode *)createGlass
{
SKNode *glass = [SKNode node];
glass.name = @”glass”;
SKSpriteNode *n1 = [SKSpriteNode spriteNodeWithColor:[self color:4] size:CGSizeMake(50, 5)];
n1.position = CGPointMake(25, –20);
[glass addChild:n1];
SKSpriteNode *n2 = [SKSpriteNode spriteNodeWithColor:[self color:4] size:CGSizeMake(50, 5)];
n2.position = CGPointMake(25, 20);
[glass addChild:n2];
SKSpriteNode *n3 = [SKSpriteNode spriteNodeWithColor:[self color:4] size:CGSizeMake(5, 40)];
n3.position = CGPointMake(0, 0);
[glass addChild:n3];
[self addChild:glass];
glass.position = CGPointMake(160, 280);
glass.physicsBody = [SKPhysicsBody bodyWithBodies:@[[SKPhysicsBody bodyWithRectangleOfSize:n1.size center:n1.position], [SKPhysicsBody bodyWithRectangleOfSize:n2.size center:n2.position],[SKPhysicsBody bodyWithRectangleOfSize:n3.size center:n3.position]]];
return glass;
}
– (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
CGPoint p = [[touches anyObject] locationInNode:self];
UIBezierPath *path = [UIBezierPath bezierPathWithArcCenter:CGPointZero radius:15 startAngle:0 endAngle:2.0*M_PI clockwise:NO];
SKShapeNode *ball = [SKShapeNode node];
ball.path = path.CGPath;
ball.position = p;
ball.fillColor = [self color:arc4random()%3+1];
[self addChild:ball];
ball.physicsBody = [SKPhysicsBody bodyWithCircleOfRadius:15];
}
– (void)didSimulatePhysics
{
[self enumerateChildNodesWithName:@”glass” usingBlock:^(SKNode *node, BOOL *stop) {
[node.physicsBody applyTorque:0.05];
}];
}
#define ColorHex(rgbValue) [SKColor colorWithRed:((float)((rgbValue & 0xFF0000) >> 16))/255.0 green:((float)((rgbValue & 0xFF00) >> 8))/255.0 blue:((float)(rgbValue & 0xFF))/255.0 alpha:1.0]
– (SKColor *)color:(NSInteger)i
{
switch (i) {
case 0:
return ColorHex(0x2E5734);
case 1:
return ColorHex(0x27804D);
case 2:
return ColorHex(0x74B466);
case 3:
return ColorHex(0x98C97A);
case 4:
return ColorHex(0xA7D9A2);
default:
break;
}
return nil;
}
@end
@interface ViewController ()
@end
@implementation ViewController
– (void)viewDidLoad
{
[super viewDidLoad];
SKView *spriteView = [[SKView alloc] initWithFrame:self.view.bounds];
[self.view addSubview:spriteView];
SKScene *scene = [[GlassScene alloc] initWithSize:spriteView.frame.size];
[spriteView presentScene:scene];
}
– (void)didReceiveMemoryWarning
{
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}
@end