ios - 在 SpriteKit 中以随机坐标生成一个节点

Question

我正在尝试生成一个我在随机坐标处创建的节点。到目前为止，我已经通过执行以下操作进行了尝试:

- (SKShapeNode *)createTargetNode
{

  int maxXCoord = CGRectGetMaxX(self.frame);
  int maxYCoord = CGRectGetMaxY(self.frame);

  int x = arc4random()% maxXCoord + 40;
  int y = arc4random()% maxYCoord + 40;

  SKShapeNode *target = [SKShapeNode new];
  CGMutablePathRef circle = CGPathCreateMutable();
  CGPathAddArc(circle, NULL, x, y, 5, 0, M_PI*2, YES);
  target.path = circle;
  target.fillColor = [SKColor redColor];
  target.strokeColor = [SKColor redColor];
  NSLog(@"%d, %d", x, y);
  return target;
}

节点有时出现在屏幕上，有时不出现。估计是越界了我该如何解决？手机横屏，坐标会变吗？

谢谢!

编辑 1:

这里是一些已经绘制的坐标:

2014-02-14 17:54:09.629 reactions[16096:70b] 221, 402
2014-02-14 17:54:10.990 reactions[16096:70b] 273, 542
2014-02-14 17:54:11.586 reactions[16096:70b] 88, 299
2014-02-14 17:54:14.660 reactions[16096:70b] 69, 306

实际上只绘制了 (88, 299) 和 (69, 306)。这是图片的链接(我还不能发布，我没有足够的声誉):

编辑 2:

这是我的主视图 Controller 。非常标准，只需加载 SKScene。

#import "DKViewController.h"
#import "DKPlayScene.h"

@implementation DKViewController

- (void)viewDidLoad
{
    [super viewDidLoad];

    SKView * skView = (SKView *)self.view;
    skView.showsFPS = YES;
    skView.showsNodeCount = YES;

    SKScene * scene = [DKPlayScene sceneWithSize:skView.bounds.size];
    scene.scaleMode = SKSceneScaleModeAspectFill;

    [skView presentScene:scene];
}

- (BOOL)shouldAutorotate
{
    return YES;
}

- (NSUInteger)supportedInterfaceOrientations
{
    if ([[UIDevice currentDevice] userInterfaceIdiom] == UIUserInterfaceIdiomPhone) {
        return UIInterfaceOrientationMaskAllButUpsideDown;
    } else {
        return UIInterfaceOrientationMaskAll;
    }
}

- (void)didReceiveMemoryWarning
{
    [super didReceiveMemoryWarning];
}

@end

这是 SKScene 的实现文件:

#import "DKPlayScene.h"
#include <stdlib.h>


@interface DKPlayScene ()

@property (nonatomic, strong) SKLabelNode *scoreLabel;
@property bool *gameHasStarted;
@property int  *score;

@end

@implementation DKPlayScene

- (id)initWithSize:(CGSize)size
{
  if (self = [super initWithSize:size]) {

    self.gameHasStarted = NO;
    self.backgroundColor = [SKColor colorWithRed:0.15 green:0.15 blue:0.3 alpha:1.0];
    self.scoreLabel = [SKLabelNode new];

    self.scoreLabel.text = @"High Score:";
    self.scoreLabel.fontSize = 10;
    self.scoreLabel.position = (CGPointMake(CGRectGetMidX(self.frame), CGRectGetMidY(self.frame) + 70));
    [self createTargetNode];
    [self addChild:self.scoreLabel];
  }
  return self;
}

- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
  [self addChild:[self createTargetNode]];
}

-(void)update:(CFTimeInterval)currentTime {

}

#pragma mark - Private

- (SKShapeNode *)createTargetNode
{

  int maxXCoord = self.frame.size.width;
  int maxYCoord = self.frame.size.height;

  int circleWidth = 6;

  int x = arc4random() % (maxXCoord - (circleWidth / 2));
  int y = arc4random() % (maxYCoord - (circleWidth / 2));

  SKShapeNode *target = [SKShapeNode new];
  CGMutablePathRef circle = CGPathCreateMutable();
  CGPathAddArc(circle, NULL, x, y, circleWidth, 0, M_PI*2, YES);
  target.path = circle;
  target.fillColor = [SKColor redColor];
  target.strokeColor = [SKColor redColor];
  NSLog(@"%d, %d", x, y);
  return target;
}

Answer 1

Sometimes the node appears on the screen, sometimes it doesn't. I guess it's going out of bounds. How can I fix that? The orientation of the phone is landscape, so do the coordinates change?

是因为使用的高度和宽度不对。

在您的代码中，[MyScene sceneWithSize:skView.bounds.size] 将始终以纵向 方向返回大小，即使它在设备/模拟器上是横向的，发生是因为你把它放在 viewDidLoad 上。

如果您想获取当前方向(横向)的大小，请将代码放在viewDidLayoutSubviews，而不是viewDidLoad。

转到“ViewController.m”，将 viewDidLoad 替换为 viewDidLayoutSubviews。

- (void)viewDidLayoutSubviews
{
    [super viewDidLayoutSubviews];

    SKView * skView = (SKView *)self.view;
    skView.showsFPS = YES;
    skView.showsNodeCount = YES;

    SKScene * scene = [MyScene sceneWithSize:skView.bounds.size];
    scene.scaleMode = SKSceneScaleModeAspectFill;

    [skView presentScene:scene];
}

文档链接:https://developer.apple.com/library/ios/documentation/uikit/reference/UIViewController_Class/Reference/Reference.html#//apple_ref/occ/instm/UIViewController/viewDidLayoutSubviews