理解Viewport的68组码

Free-Lancer

Understanding group code 68 of AcDbViewport                                                        By Gopinath Taget
  Group code 68 represents the viewport status field, and the value is an integer with the following meaning:

  0: the viewport is off so that the view within it is not displayed on screen.

  Non-zero value: The viewport is on so that the view within it is displayed on screen as long as this viewport is active (only certain number of viewports can be active at any time. This number is reported by the MAXACTVP system variable). And the value indicates the order of stacking for the viewports, where 1 is the active viewport, 2 is the next, etc..
               

68	视口状态字段： -1 = 开，但是在屏幕上完全不可见，或者因为当前已超出 $MAXACTVP 计数，而成为一个不活动的视口。 0 = 关 <正值> = 开并处于活动状态。该值表示视口堆栈的次序，其中 1 是活动视口，下一个是 2，依此类推

海天风云

原来如此，受教 了，谢谢！