我一直在尝试在 Xcode 上使用鼠标事件的 Sprite 制作的 2 个点之间绘制一条 Sprite 线。
我一直在遵循此链接中论坛上给出的步骤: cocos2d forums
但是当我运行代码时,我得到的线路一直延伸到模拟器。就像这样。
该行应该在第二个鼠标 Sprite 生成的代码处停止,但它并没有停止,而是一直继续下去。
我的场景是这样的。
我的 .h 类
#import <Foundation/Foundation.h>
#import "cocos2d.h"
#import "Constants.h"
#import "SceneManager.h"
@interface EscenaInfo : CCLayer{
CGPoint lastTouchPoint;
CCSprite * background;
}
@property (nonatomic, assign) BOOL iPad;
@end
我的.mm
#import "EscenaInfo.h"
@implementation EscenaInfo
@synthesize iPad;
- (void)onBack: (id) sender {
/*
This is where you choose where clicking 'back' sends you.
*/
[SceneManager goMenuPrincipal];
}
- (void)addBackButton {
if (self.iPad) {
// Create a menu image button for iPad
CCMenuItemImage *goBack = [CCMenuItemImage itemFromNormalImage:@"Arrow-Normal-iPad.png"
selectedImage:@"Arrow-Selected-iPad.png"
target:self
selector:@selector(onBack:)];
// Add menu image to menu
CCMenu *back = [CCMenu menuWithItems: goBack, nil];
// position menu in the bottom left of the screen (0,0 starts bottom left)
back.position = ccp(64, 64);
// Add menu to this scene
[self addChild: back];
}
else {
// Create a menu image button for iPhone / iPod Touch
CCMenuItemImage *goBack = [CCMenuItemImage itemFromNormalImage:@"Arrow-Normal-iPhone.png"
selectedImage:@"Arrow-Selected-iPhone.png"
target:self
selector:@selector(onBack:)];
// Add menu image to menu
CCMenu *back = [CCMenu menuWithItems: goBack, nil];
// position menu in the bottom left of the screen (0,0 starts bottom left)
back.position = ccp(32, 32);
// Add menu to this scene
[self addChild: back];
}
}
- (id)init {
if( (self=[super init])) {
// Determine Screen Size
CGSize screenSize = [CCDirector sharedDirector].winSize;
//Boton en la Interfaz del iPad
self.iPad = UI_USER_INTERFACE_IDIOM() == UIUserInterfaceIdiomPad;
// Put a 'back' button in the scene
[self addBackButton];
///
self.isTouchEnabled = YES;
lastTouchPoint = ccp(-1.0f,-1.0f);
///
[CCTexture2D setDefaultAlphaPixelFormat:kCCTexture2DPixelFormat_RGB565];
background = [CCSprite spriteWithFile:@"background.png"];
background.anchorPoint = ccp(0,0);
[self addChild:background z:-1];
[CCTexture2D setDefaultAlphaPixelFormat:kCCTexture2DPixelFormat_Default];
}
return self;
}
- (void) dealloc
{
// in case you have something to dealloc, do it in this method
// in this particular example nothing needs to be released.
// cocos2d will automatically release all the children (Label)
// don't forget to call "super dealloc"
[super dealloc];
}
- (void)ccTouchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
UITouch *touch = [touches anyObject];
if( touch ) {
CGPoint location = [touch locationInView: [touch view]];
location = [[CCDirector sharedDirector] convertToGL:location];
CCLOG(@"location(%f,%f)", location.x, location.y);
if( CGPointEqualToPoint(lastTouchPoint, ccp(-1.0f,-1.0f) ) )
{
lastTouchPoint = ccp(location.x, location.y);
CCSprite *circle = [CCSprite spriteWithFile:@"circle.png"];
[circle setPosition:lastTouchPoint];
[self addChild:circle];
CCLOG(@"initial touchpoint set. to (%f,%f)", lastTouchPoint.x, lastTouchPoint.y);
}
else {
CCLOG(@"lastTouchPoint is now(%f,%f), location is (%f,%f)", lastTouchPoint.x, lastTouchPoint.y, location.x, location.y);
CGPoint diff = ccpSub(location, lastTouchPoint);
float rads = atan2f( diff.y, diff.x);
float degs = -CC_RADIANS_TO_DEGREES(rads);
float dist = ccpDistance(lastTouchPoint, location);
CCSprite *line = [CCSprite spriteWithFile:@"line.png"];
[line setAnchorPoint:ccp(0.0f, 0.5f)];
[line setPosition:lastTouchPoint];
[line setScaleX:dist];
[line setRotation: degs];
[self addChild:line];
CCSprite *circle = [CCSprite spriteWithFile:@"circle.png"];
[circle setPosition:location];
[self addChild:circle];
// lastTouchPoint = ccp(location.x, location.y);
lastTouchPoint = ccp(-1.0f,-1.0f);
}
}
}
@end
有人知道怎么解决吗?我一直在尝试很多事情,但没有对我有用,或者可能会指出我的错误。我真的很感激。
最佳答案
我没有运行代码,但它看起来相当简单。问题的原因出在这一段:
float dist = ccpDistance(lastTouchPoint, location);
CCSprite *line = [CCSprite spriteWithFile:@"line.png"];
[line setAnchorPoint:ccp(0.0f, 0.5f)];
[line setPosition:lastTouchPoint];
[line setScaleX:dist];
此代码计算两个触摸点之间的距离(以点(像素)为单位),创建一个新 Sprite (将成为线)并将 anchor 设置在右侧,垂直居中。它将其定位在最后一次触摸点,然后根据之前计算的距离设置 Sprite 宽度的比例。这个比例因子将确保 Sprite “长”到足以到达两点之间。
您的问题:
这没有考虑您正在加载的图像的初始尺寸 (line.png)。如果这不是 1x1 尺寸的 png,那么 setScale
将使生成的 sprite 太大 - 您遇到的超限。
解决方案
使 line.png 成为 1 x 1 像素的图像。您的代码将完美运行,尽管您的代码非常细且不美观。
或者,为了获得最佳效果,通过考虑 line.png 的宽度来计算 Sprite 的比例。这样 Sprite 可以更详细并且不会溢出。
将 setScaleX
行更改为:
[line setScaleX:dist / line.boundingBox.size.width];
关于ios - 在 Cocos2d 中的 Sprites 制作的两点之间绘制一条线 Sprite,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/8749853/