用QT实现的linux下的画曲线功能，主要实现正弦波，方波等波形绘制。-Using QT to achieve under the Linux curve drawing function, the main realization of sine wave, square wave, waveform drawing.

1、Qt实现绘制正弦曲线 2、实现拖动效果 3、实现放大、缩小 4、实现绘制越界问题(1, Qt draw sine curve 2, achieve drag effect 3, achieve amplification and contraction 4, the realization of cross-border rendering problems)