ios - 在 CGContextAddPath 之后删除路径

Question

我想知道在我使用 CGContextAddPath 添加 CGPath 之后是否有办法从我的上下文中删除它，这样我的绘图命令就不再局限于之后的路径尺寸。

Answer 1

您应该使用 CGContextBeginPath(...) 从指定上下文中删除先前添加的路径。

来自 Apple's documentation 的方法的讨论:

A graphics context can have only a single path in use at any time. If the specified context already contains a current path when you call this function, Quartz discards the old path and any data associated with it.

The current path is not part of the graphics state. Consequently, saving and restoring the graphics state has no effect on the current path.

类似于下面:

CGContextRef context = UIGraphicsGetCurrentContext();

CGContextAddPath(context, ellipsePath);
CGContextDrawPath(context, kCGPathFill);

CGContextBeginPath(context);

CGContextAddPath(context, strokePath);
CGContextDrawPath(context, kCGPathStroke);