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我在我的应用程序中使用 CGContextAddLineToPoint 画一条线现在我想从给定点删除线我该怎么做我正在使用触摸画线
你可以抹去,
给定这两个点,通过设置CGContextSetBlendMode(context, kCGBlendModeClear).
CGContextSetBlendMode(context, kCGBlendModeClear)