如何获得点在图层内的绝对位置

Question

如何获得CALayer中CGPoint的绝对位置。我需要这个精确的像素绘制

编辑：绝对到屏幕

Answer 1

递归地点击测试超层，直到到达根层：

CGPoint originalPoint = // wherever from you obtain your original point
CALayer *layer = self;
CGPoint point = originalPoint;
while (layer.superlayer)
{
    point = [layer convertPoint:point toLayer:layer.superlayer];
    layer = layer.superlayer;
}
// here `point' will contain the exact position