程序中了给了一个可以重复利用的二维曲线绘制类CGraphics，并派生了线形曲线类模板、单对数曲线类模版、双对数曲线类模版。

程序中了给了一个可以重复利用的二维曲线绘制类CGraphics，并派生了线形曲线类模板、单对数曲线类模版、双对数曲线类模版。-Procedure to the repeat use of a two-dimensional curve drawing category CGraphics, and derived a linear curve of class template, a one-on-curve-type template

view里面绘图，然后实现放大，缩小，区域放大，等一系列功能-view inside the drawing, and then realize zoom, zoom area, and a series of functions

Theory of Operation: A cog is launched which processes commands via the PUB routines. Points, lines, arcs, sprites, text, and polygons are rasterized into a specified stretch of memory which serves