Cocos2d中各种坐标位置关系

转自：http://blog.csdn.net/liuhongwei123888/article/details/6684279

先看一段代码：

[cpp] view
plaincopy

-(id) init

{

// always call "super" init

// Apple recommends to re-assign "self" with the "super" return value

if( (self=[super init])) {

CCTMXTiledMap *gameWorld = [CCTMXTiledMap tiledMapWithTMXFile:@"PositionText.tmx"];

[self addChild:gameWorld];

CGSize winSize = [[CCDirector sharedDirector] winSize];

CCLOG(@"gameWorld.mapSize.width:%.2f gameWorld.mapSize.height:%.2f",gameWorld.mapSize.width, gameWorld.mapSize.height);

CCLOG(@"gameWorld.tileSize.width: %.2f gameWorld.tileSize.height:%.2f", gameWorld.tileSize.width, gameWorld.tileSize.height);

CCLOG(@"winSize.width:%.2f winSize.height:%.2f", winSize.width, winSize.height);

CCSprite *pointSprite = [CCSprite spriteWithFile:@"point.png"];

[gameWorld addChild:pointSprite z:2 tag:1];

pointSprite.position = ccp(20,20);

pointSprite.anchorPoint = ccp(0.5, 0.5);

CCSprite *rectSprite = [CCSprite spriteWithFile:@"myrect.png"];

[gameWorld addChild:rectSprite z:1 tag:1];

rectSprite.position = ccp(20,20);

rectSprite.anchorPoint = ccp(0.5, 0.5);

}

return self;

}

1、加载地图：

[cpp] view
plaincopy

CCTMXTiledMap *gameWorld = [CCTMXTiledMap tiledMapWithTMXFile:@"PositionText.tmx"];

2、获取手机屏幕大小（320，480）

[cpp] view
plaincopy

CGSize winSize = [[CCDirector sharedDirector] winSize];

3、地图格子数：

[cpp] view
plaincopy

gameWorld.mapSize （10，10）

4、地图格子大小：

[cpp] view
plaincopy

gameWorld.tileSize （20，20）

5、整个地图大小：

gameWorld.mapSize * gameWorld.tileSize;

当然这里所说的是地图格子是个正方形，非正方形也容易啦。

6、anchor属性

1） 添加一个精灵，这个精灵是个像素为1*1的红色图片，设置坐标为20，20，即在地图的第一个格子的右上角，设置anchorPoint为（0.5， 0.5）

2） 再添加一个精灵，这个精灵是个像素为20*20的蓝色图片，设置坐标为20，20，即在地图的第一个格子的右上角，同样设置anchorPoint为（0.5， 0.5）

运行效果是矩形精灵的中心和在点精灵的位置，即矩形精灵的锚点为第一个格子的右上角（20，20）坐标 处

去掉两个精灵的anchorPoint属性

运行效果和上面相同

设置rectSprite的anchorPoint为ccp(0,0)

运行效果是矩形精灵的左下角与点精灵重合。

设置rectSprite的anchorPoint为ccp(1,1)

运行效果是矩形精灵的右上角与点精灵重合。

同理设置ccp(0.5, 1) , ccp(1, 0.5)等

由上面可以得出：

1）anchorPoint属性默认为ccp(0.5, 0.5)

2）当设置（0，0）时是以左下角为锚点

3）当设置（1， 1）时是以右上角角为锚点

4）由此可以自己推论到底该把锚点设置在哪里

Cocos2D使用的是OpenGL坐标系

OpenGL坐标系：原点在左下角， X轴向右，Y轴向上

IPhone屏幕坐标系：原点在左上角，X轴向右，Y轴向下

很简单的判断方法：由于Cocos2D的坐标系的原点在左下角。所以精灵内部坐标原点也是左下角，即当anchorPoint为（0， 0）时即以左下角为锚点，为（1，1）时就以右上角为锚点，当然（0.5， 0.5）就是以精灵中心为锚点了。由此可以推算出-2,-3.... 2, 3.... 等值时精灵锚点坐标。

7、坐标转换

[cpp] view
plaincopy

-(id) init

{

// always call "super" init

// Apple recommends to re-assign "self" with the "super" return value

if( (self=[super init])) {

CCTMXTiledMap *gameWorld = [CCTMXTiledMap tiledMapWithTMXFile:@"PositionText.tmx"];

[self addChild:gameWorld];

CGSize winSize = [[CCDirector sharedDirector] winSize];

CCLOG(@"gameWorld.mapSize.width:%.2f gameWorld.mapSize.height:%.2f",gameWorld.mapSize.width, gameWorld.mapSize.height);

CCLOG(@"gameWorld.tileSize.width: %.2f gameWorld.tileSize.height:%.2f", gameWorld.tileSize.width, gameWorld.tileSize.height);

CCLOG(@"winSize.width:%.2f winSize.height:%.2f", winSize.width, winSize.height);

CCSprite *pointSprite = [CCSprite spriteWithFile:@"point.png"];

[gameWorld addChild:pointSprite z:2 tag:1];

pointSprite.position = ccp(20,20);

//pointSprite.anchorPoint = ccp(0.5, 0.5);

CCSprite *rectSprite = [CCSprite spriteWithFile:@"myrect.png"];

[gameWorld addChild:rectSprite z:1 tag:1];

rectSprite.position = ccp(40,40);

rectSprite.anchorPoint = ccp(2, 2);

[self setIsTouchEnabled:YES];

}

return self;

}

- (void) registerWithTouchDispatcher {

[[CCTouchDispatcher sharedDispatcher] addTargetedDelegate:self priority:INT_MIN + 1 swallowsTouches:YES];

}

- (BOOL) ccTouchBegan:(UITouch *)touch withEvent:(UIEvent *)event {

CGPoint point = [touch locationInView: [touch view]];

CCLOG(@"Screen coordX: %.2f coordY: %.2f", point.x, point.y);

point = [[CCDirector sharedDirector] convertToGL: point];

CCLOG(@"OpenGL coordX: %.2f coordY: %.2f", point.x, point.y);

point = [self convertToNodeSpace: point];

CCLOG(@"CCNode1 coordX: %.2f coordY: %.2f", point.x, point.y);

point = [self convertTouchToNodeSpace: touch];

CCLOG(@"CCNode2 coordX: %.2f coordY: %.2f", point.x, point.y);

point = [[CCDirector sharedDirector] convertToUI:point];

CCLOG(@"UIView coordX: %.2f coordY: %.2f", point.x, point.y);

point = [rectSprite convertTouchToNodeSpaceAR:touch];

CCLOG(@"TouchAR coordX: %.2f coordY: %.2f", point.x, point.y);

return YES; CCNode

}

- (void) ccTouchMoved:(UITouch *)touch withEvent:(UIEvent*)event {

}

- (void) ccTouchEnded:(UITouch *)touch withEvent:(UIEvent*)event {

}

上面的代码添加了UIView的事件处理。由于屏幕和Cocos2D采用不同的坐标系，所以我们需要进行坐标转换。

1）首先获取屏幕坐标

2）将屏幕坐标转换为OpenGL的坐标

3）将OpenGL的坐标转换为Cocos2D的坐标。

从运行结果可以看出Node1和Node2打印出的坐标相同。因为Cocos2D给我们写了covertTouchToNodeSpace方法，可以看看它的源码：

[cpp] view
plaincopy

- (CGPoint)convertTouchToNodeSpace:(UITouch *)touch

{

CGPoint point = [touch locationInView: [touch view]];

point = [[CCDirector sharedDirector] convertToGL: point];

return [self convertToNodeSpace:point];

}

至于为什么OpenGL和Node1输出既然相同，为什么还要使用convertToNodeSpace，由于能力有限，希望大牛们能给告诉我答案。

UIView输出的是将Cocos2D坐标转换为屏幕即quartz坐标。

4) convertTouchToNodeSpaceAR是将触摸点转换为相对于rectSprite的坐标

8、判断触摸点是否在制定的精灵上

[cpp] view
plaincopy

- (BOOL) ccTouchBegan:(UITouch *)touch withEvent:(UIEvent *)event {

CGPoint point = [touch locationInView: [touch view]];

CCLOG(@"Screen coordX: %.2f coordY: %.2f", point.x, point.y);

point = [[CCDirector sharedDirector] convertToGL: point];

CCLOG(@"OpenGL coordX: %.2f coordY: %.2f", point.x, point.y);

point = [self convertToNodeSpace: point];

CCLOG(@"CCNode1 coordX: %.2f coordY: %.2f", point.x, point.y);

point = [self convertTouchToNodeSpace: touch];

CCLOG(@"CCNode2 coordX: %.2f coordY: %.2f", point.x, point.y);

//point = [[CCDirector sharedDirector] convertToUI:point];

//CCLOG(@"UIView coordX: %.2f coordY: %.2f", point.x, point.y);

CCLOG(@"%d", rectSprite.textureRect.size.width);

CGRect rect = [rectSprite textureRect];

rect = CGRectMake(0, 0, rect.size.width, rect.size.height);

CCLOG(@"orgX: %.2f orgY: %.2f width:%.2f height: %.2f",rect.origin.x, rect.origin.y, rect.size.width, rect.size.height);

point = [rectSprite convertTouchToNodeSpaceAR:touch];

CCLOG(@"TouchAR coordX: %.2f coordY: %.2f", point.x, point.y);

if(CGRectContainsPoint(rect, point)) {

CCLOG(@"You touched in the rectSprite");

}

return YES;

}

9、获取触摸的是哪个tile，并改变该tile.

[cpp] view
plaincopy

CCSprite *rectSprite;

CCTMXTiledMap *gameWorld;

int speed = 10;

-(id) init

{

// always call "super" init

// Apple recommends to re-assign "self" with the "super" return value

if( (self=[super init])) {

gameWorld = [CCTMXTiledMap tiledMapWithTMXFile:@"PositionText.tmx"];

[self addChild:gameWorld];

CGSize winSize = [[CCDirector sharedDirector] winSize];

CCLOG(@"gameWorld.mapSize.width:%.2f gameWorld.mapSize.height:%.2f",gameWorld.mapSize.width, gameWorld.mapSize.height);

CCLOG(@"gameWorld.tileSize.width: %.2f gameWorld.tileSize.height:%.2f", gameWorld.tileSize.width, gameWorld.tileSize.height);

CCLOG(@"winSize.width:%.2f winSize.height:%.2f", winSize.width, winSize.height);

CCSprite *pointSprite = [CCSprite spriteWithFile:@"point.png"];

[gameWorld addChild:pointSprite z:2 tag:1];

pointSprite.position = ccp(20,20);

pointSprite.anchorPoint = ccp(0.5, 0.5);

rectSprite = [CCSprite spriteWithFile:@"myrect.png"];

[gameWorld addChild:rectSprite z:0 tag: 3];

rectSprite.position = ccp(40, 40);

rectSprite.anchorPoint = ccp(0, 0);

[self setIsTouchEnabled:YES];

}

return self;

}

- (void) registerWithTouchDispatcher {

[[CCTouchDispatcher sharedDispatcher] addTargetedDelegate:self priority:INT_MIN + 1 swallowsTouches:YES];

}

- (BOOL) ccTouchBegan:(UITouch *)touch withEvent:(UIEvent *)event {

CGPoint point = [touch locationInView: [touch view]];

point = [self convertTouchToNodeSpace: touch];

CCLOG(@"CCNode2 coordX: %.2f coordY: %.2f", point.x, point.y);

CGPoint tilePos = [self tilePosition:point];

if(tilePos.x == -1 || tilePos.y == -1) return NO;

CCTMXLayer *ly = [gameWorld layerNamed:@"Layer 0"];

if([ly tileGIDAt:tilePos] != 3) {

[ly setTileGID:0 at: tilePos];

}

return YES;

}

- (void) ccTouchMoved:(UITouch *)touch withEvent:(UIEvent*)event {

}

- (void) ccTouchEnded:(UITouch *)touch withEvent:(UIEvent*)event {

}

- (CGPoint) tilePosition:(CGPoint)pos {

CGPoint point;

CCTMXLayer *ly = [gameWorld layerNamed:@"Layer 0"];

if(ly== nil) {

CCLOG(@"Error: Layer not found!");

return ccp(-1, -1);

}

CGSize layerSize = [ly layerSize];

CGSize tileSize = [gameWorld tileSize];

int x = pos.x / tileSize.width;

int y = layerSize.height - pos.y / tileSize.height;

if((x >= 0) && (x < layerSize.width) && (y >= 0) && (y < layerSize.height)) {

point = ccp(x, y);

} else {

point = ccp(-1, -1);

}

if(point.x < 0) return ccp(-1, -1);

if(point.y < 0) return ccp(-1, -1);

if(point.x >= layerSize.width) return ccp(-1, -1);

if(point.y >= layerSize.height) return ccp(-1, -1);

CCLOG(@"%d, %d", x, y);

return point;

}

分享到：