我想沿着touchesmoved收集的点在sprite工具包中画一条线.
什么是最有效的方式？我尝试了几次,我的线在y轴上是错误的,或者占用了很多处理能力,fps下降到10秒.
有任何想法吗？
解决方法
您可以定义CG路径并通过在触摸移动功能中添加线条或弧线来修改它.之后,您可以从路径创建SKShapeNode并根据需要进行配置.
如果要在手指在屏幕上移动时绘制线条,则可以在触摸以空路径开始时创建形状节点,然后对其进行修改.
如果要在手指在屏幕上移动时绘制线条,则可以在触摸以空路径开始时创建形状节点,然后对其进行修改.
编辑：我写了一些代码,它适用于我,绘制一个简单的红线.
在你的MyScene.m中：
@interface MyScene()
{
CGMutablePathRef pathToDraw;
SKShapeNode *lineNode;
}
@end
@implementation
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
UITouch* touch = [touches anyObject];
CGPoint positionInScene = [touch locationInNode:self];
pathToDraw = CGPathCreateMutable();
CGPathMoveToPoint(pathToDraw,NULL,positionInScene.x,positionInScene.y);
lineNode = [SKShapeNode node];
lineNode.path = pathToDraw;
lineNode.strokeColor = [SKColor redColor];
[self addChild:lineNode];
}
- (void)touchesMoved:(NSSet*)touches withEvent:(UIEvent*)event
{
UITouch* touch = [touches anyObject];
CGPoint positionInScene = [touch locationInNode:self];
CGPathAddLineToPoint(pathToDraw,positionInScene.y);
lineNode.path = pathToDraw;
}
- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event
{
// delete the following line if you want the line to remain on screen.
[lineNode removeFromParent];
CGPathRelease(pathToDraw);
}
@end
