#|《Quartz 2D编程指南》之【graphics context】图形上下文的作用、分类、状态的保持、恢复、上下文的矩阵操作（修改上下文的形变）图形上下文|graphics|core|graphic

文章目录

引言
I、作用
II、drawing destination(分类)
III、The Graphics State：绘图状态
IV、图形上下文栈的操作：状态的保持、恢复
V、上下文的矩阵操作
see also

【#|《Quartz 2D编程指南》之【graphics context】图形上下文的作用、分类、状态的保持、恢复、上下文的矩阵操作（修改上下文的形变）】
引言

The Graphics Context：数据类型为CGContextRef

You can think of a graphics context as a drawing destination. A graphics context encapsulates all of the information needed to draw to an underlying canvas,including the current drawing attributes and a device-specific representation of the digital paint on the