SpriteKit--SKLableNode

首先了解一个SKSpriteNode的anchorPoint

skspriteNodeAnchorpoint.png

1.一个SKLableNode 加在一个SKSpriteNode的时候效果如下：

    SKSpriteNode *bgNode = [SKSpriteNode spriteNodeWithColor:[UIColor blueColor] size:CGSizeMake(260, 70)];
    bgNode.position = CGPointMake(self.size.width/2, self.size.height/2);
    [self addChild:bgNode];
    
    SKLabelNode *lab = [SKLabelNode labelNodeWithText:@"lable text did finish"];
    [bgNode addChild:lab];

default.png

其中有几个默认的隐藏:

    bgNode.anchorPoint = CGPointMake(0.5, 0.5);//
    lab.position = CGPointMake(0, 0); //
    lab.horizontalAlignmentMode = SKLabelHorizontalAlignmentModeCenter;//
    lab.verticalAlignmentMode = SKLabelVerticalAlignmentModeBaseline;//

可以看出lab是以父节点bgNode的中心渲染的。可以将lab的verticalAlignmentMode更改为中心

    lab.verticalAlignmentMode = SKLabelVerticalAlignmentModeCenter;//

chang1.png

2.如果将父节点bgNode的anchorPoint改为(0,0)

    SKSpriteNode *bgNode = [SKSpriteNode spriteNodeWithColor:[UIColor blueColor] size:CGSizeMake(260, 70)];
    bgNode.position = CGPointMake(self.size.width/2, self.size.height/2);
    [self addChild:bgNode];
    
    bgNode.anchorPoint = CGPointMake(0, 0);//
    
    SKLabelNode *lab = [SKLabelNode labelNodeWithText:@"lable text did finish"];
    [bgNode addChild:lab];
    lab.position = CGPointMake(0, 0); //
    lab.horizontalAlignmentMode = SKLabelHorizontalAlignmentModeCenter;//
    lab.verticalAlignmentMode = SKLabelVerticalAlignmentModeCenter;//

chang2.png

可以清楚的看到 lab的中心点的位置

总结：SKLabelNode的默认postition是 (0,0),它是以父节点的anchorPoint所在位置渲染的。父节点有9个anchorPoint。所以一般来说不用去更改SKLabelNode的position,去更改父节点的anchorPoint就可以达到理想的效果。

3.比如想要左对齐，上下居中:

    SKSpriteNode *bgNode = [SKSpriteNode spriteNodeWithColor:[UIColor blueColor] size:CGSizeMake(260, 70)];
    bgNode.position = CGPointMake(self.size.width/2, self.size.height/2);
    [self addChild:bgNode];
    
    bgNode.anchorPoint = CGPointMake(0, 0.5);//
    
    SKLabelNode *lab = [SKLabelNode labelNodeWithText:@"lable text did finish"];
    [bgNode addChild:lab];
    
    lab.position = CGPointMake(0, 0); //
    lab.horizontalAlignmentMode = SKLabelHorizontalAlignmentModeLeft;//
    lab.verticalAlignmentMode = SKLabelVerticalAlignmentModeCenter;//

chang3.png