Uncommon Knowledge - WC_Vprev%

The Vspace image for the screen as it was before the window was invoked. Note that although this is nearly identical to a Video.Rw image variable it cannot be used without some pre-processing as each VSPACE image contains a 25 byte header block.

If it is desired to redisplay the background using the VPrev variable one would use a section of code similar to the following.

  Subroutine Display_VPrev
    $Insert Include, Window_Common%
    Declare Function Video.Rw
    CrtW = Seq(WC_VPrev%[3,1] - 1
    CrtH = Seq(WC_VPrev%[5,1]) - 1
    Img = WC_Prev%[26,10000]
    OK = Video.Rw(0, 0, CrtW, CrtH, "W", Img)
  Return

(Volume 3, Issue 10, Page 14)