頭をくるくる回転させて弾を打ち出す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 TankScene : SKScene
@property (nonatomic) CGPoint touchPoint;
@property (nonatomic) int turnHead;
@property (nonatomic, strong) NSMutableArray *timer;
@end
@implementation TankScene
– (void)didMoveToView:(SKView *)view
{
self.backgroundColor = [UIColor colorWithWhite:0.9 alpha:1];
self.physicsWorld.gravity = CGVectorMake(0, 0);
self.physicsBody = [SKPhysicsBody bodyWithEdgeLoopFromRect:self.frame];
[self createTank];
[self createTurnButton];
self.timer = [NSMutableArray array];
}
– (void)createTank
{
SKNode *tank = [SKNode node];
tank.name = @”tank”;
tank.position = CGPointMake(160, 80);
[self addChild:tank];
SKSpriteNode *body = [SKSpriteNode spriteNodeWithColor:[SKColor colorWithRed:0 green:0.4 blue:0 alpha:1] size:CGSizeMake(80, 48)];
[tank addChild:body];
for (int i=0; i<2; i++) {
SKSpriteNode *tire = [SKSpriteNode spriteNodeWithColor:[SKColor darkGrayColor] size:CGSizeMake(85, 15)];
tire.position = CGPointMake(0, i ? –33 : 33);
[tank addChild:tire];
}
SKNode *head = [SKNode node];
head.name = @”head”;
[tank addChild:head];
UIBezierPath *path = [UIBezierPath bezierPathWithArcCenter:CGPointZero radius:30 startAngle:0 endAngle:2.0*M_PI clockwise:NO];
SKShapeNode *circle = [SKShapeNode node];
circle.path = path.CGPath;
circle.fillColor = [UIColor colorWithRed:0 green:0.6 blue:0 alpha:1];
[head addChild:circle];
SKSpriteNode *port = [SKSpriteNode spriteNodeWithColor:[SKColor colorWithRed:0 green:0.6 blue:0 alpha:1] size:CGSizeMake(15, 40)];
port.position = CGPointMake(0, 40);
[head addChild:port];
tank.physicsBody = [SKPhysicsBody bodyWithRectangleOfSize:body.size];
}
– (void)createTurnButton
{
UIBezierPath *path = [UIBezierPath bezierPathWithArcCenter:CGPointZero radius:70 startAngle:0 endAngle:2.0 * M_PI clockwise:NO];
SKShapeNode *btn = [SKShapeNode node];
btn.position = CGPointMake(320, 0);
btn.fillColor = [SKColor colorWithRed:0.3 green:0.6 blue:0.6 alpha:1];
btn.path = path.CGPath;
[self addChild:btn];
btn.name = @”turn”;
}
– (void)tick
{
int count = self.timer.count;
if (count > 60) {
[self.timer enumerateObjectsUsingBlock:^(SKNode *n, NSUInteger idx, BOOL *stop) {
[n removeFromParent];
}];
[self shoot];
[self.timer removeAllObjects];
} else {
SKSpriteNode *n = [SKSpriteNode spriteNodeWithColor:[SKColor redColor] size:CGSizeMake(30, 5)];
n.position = CGPointMake(300, 100 + 5 * count);
[self addChild:n];
[self.timer addObject:n];
}
}
– (void)shoot
{
SKNode *tank = [self childNodeWithName:@”tank”];
SKNode *head = [tank childNodeWithName:@”head”];
SKSpriteNode *ball = [SKSpriteNode spriteNodeWithColor:[UIColor blackColor] size:CGSizeMake(10, 10)];
float angle = head.zRotation + M_PI * 0.5;
float x = tank.position.x + 70 * cos(angle);
float y = tank.position.y + 70 * sin(angle);
ball.position = CGPointMake(x, y);
ball.physicsBody = [SKPhysicsBody bodyWithRectangleOfSize:ball.size];
[self addChild:ball];
[ball.physicsBody applyImpulse:CGVectorMake(cos(angle), sin(angle))];
}
– (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
SKShapeNode *btn = (SKShapeNode *)[self childNodeWithName:@”turn”];
CGPoint p = [[touches anyObject] locationInNode:self];
if ([btn containsPoint:p]) {
btn.alpha = (btn.alpha == 1.0) ? 0.7 : 1.0;
self.turnHead = (self.turnHead + 1) % 4;
return;
}
self.touchPoint = p;
}
– (void)update:(NSTimeInterval)currentTime
{
SKNode *tank = [self childNodeWithName:@”tank”];
float dx = tank.position.x – self.touchPoint.x;
if (dx != 0 && !CGPointEqualToPoint(self.touchPoint, CGPointZero)) {
tank.physicsBody.velocity = CGVectorMake(dx > 0 ? –10 : 10, 0);
}
SKNode *head = [tank childNodeWithName:@”head”];
if (self.turnHead % 2 == 1) {
head.zRotation += (self.turnHead==1) ? 0.01 : –0.01;
}
[self tick];
}
@end
@interface ViewController ()
@end
@implementation ViewController
– (void)viewDidLoad
{
[super viewDidLoad];
SKView *spriteView = [[SKView alloc] initWithFrame:self.view.bounds];
[self.view addSubview:spriteView];
SKScene *scene = [[TankScene alloc] initWithSize:spriteView.frame.size];
[spriteView presentScene:scene];
}
– (void)didReceiveMemoryWarning
{
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}
@end