在微机过程控制中,有时要求同时绘制多幅画面,各画面的状态随现场采集的信号而变化。若采用直接向显示缓冲区(简称显缓区)作图的方式绘制各幅画面,其绘图速度很慢,而且每次只能绘制一幅画面。为达到快速变换画面及同时绘制多幅画面,就应尽量避免与显缓区接口打交道,而直接开辟内存RAM作图缓冲区(简称RAM缓区),这样就可在多个RAM缓区内作出多个不同的画面,一旦需要某幅画面,就将其直接传送到显缓区。原用于 In computer process control, it is sometimes required to draw multiple pictures at the same time. The states of the pictures vary with the signals collected on site. If the direct use of the display buffer (referred to as buffer zone) for drawing the various pictures, the drawing speed is very slow, and can only draw one picture at a time. In order to achieve rapid change screen and draw multiple pictures at the same time, we should try our best to avoid dealing with the interface in the buffer area and directly open up the memory RAM buffer (abbreviated as RAM buffer area) so that we can make it in multiple RAM buffer area A number of different images, once the need for a picture, it will be sent directly to the buffer zone. Used for