画板CAD缩放，就像CAD画图程序，画出来的笔画可以用鼠标滚轮，滚动放大和缩小。-The Sketchpad CAD scaling, the drawn strokes like a CAD drawing program, you can use the mouse wheel to scroll zoom in and out.

matlab源码，动态鼠标画图，实时显示鼠标轨迹-matlab source code, dynamic drawing mouse, mouse track real-time display