Communicating With the System Windows but will not delete the vision window. You can close and detach from the vision window, but you cannot delete it. To preserve the vision system pull-down menus, open the window in write-only mode: FOPEN (glun) "Vision /WRITEONLY" The following example opens the vision window, writes to the vision window, and detaches the vision window: .PROGRAM label.blob() ; ABSTRACT: This program demonstrates how to attach to the ; vision window and how to use the millimeter scaling mode of ; the GTRANS instruction to label a "blob" in the vision ; window.
; AUTO vlun cam = 1 ; Attach the vision window and get a logical unit number ATTACH (vlun, 4) "GRAPHICS" IF IOSTAT(vlun) 0 GOTO 100 FOPEN (vlun) "Vision" ;Open the vision window IF IOSTAT(vlun) 0 GOTO 100 ; Select display mode and graphics mode VDISPLAY (cam) 1, 1 ;Display grayscale frame and graphics ; Take a picture and locate an object VPICTURE (cam) ;Take a processed picture VLOCATE (cam, 2) "?" ;Attempt to locate an object IF VFEATURE(1) THEN ;If an object was found... GCOLOR (vlun) 1 ;Select the color black GTRANS (vlun, 2) ;Select millimeter scaling GTYPE (vlun) DX(vis.loc), DY(vis.loc), "Blob", 3 ELSE ;Else if object was NOT found...
GCOLOR (vlun) 3 ;Select the color red GTRANS (vlun, 0) ;Select pixel scaling GTYPE (vlun) 100, 100, "No object found!", 3 END ; Detach (frees up the communications path) DETACH (vlun) 100 IF (IOSTAT(vlun) 0) THEN ; Check for errors TYPE $ERROR(IOSTAT(vlun)) END .END eV+Language User's Guide, v2.x, 18318-000 Rev A Page 177