CGLayer、CALayer、CGContext有什么区别?
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所以,正如文档所说
QuartzCore 框架 中的CALayer是
The CALayer class manages image-based content and allows you to
perform animations on that content. Layers are often used to provide
the backing store for views but can also be used without a view to
display content.
更多信息请查看https://developer.apple.com/reference/quartzcore/calayer
Core Graphics framework 中的CGLayer是
Layer objects are useful for offscreen drawing and can be used in much
the same way that a bitmap context can be used. In fact, a CGLayer
object is a much better representation than a bitmap context. Using
CGLayer objects can improve performance, particularly when you need to
capture a piece of drawing that you stamp repeatedly (using the same
scale factor and orientation)
更多信息请查看https://developer.apple.com/reference/coregraphics/1666309-cglayer
Note CGLayer objects are unrelated to Core Animation layers (CALayer
objects).
Core Graphics framework 中的 CGContext 是
A graphics context contains drawing parameters and all device-specific
information needed to render the paint on a page to the destination,
whether the destination is a window in an application, a bitmap image,
a PDF document, or a printer.
更多信息请查看https://developer.apple.com/reference/coregraphics/1666363-cgcontext
关于ios - CGLayer、CALayer和CGContext的区别,我们在Stack Overflow上找到一个类似的问题:
https://stackoverflow.com/questions/39695032/
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