0022877: Implementation of DRAW commands for non-regression testing:

- TKIVtkDraw toolkit provides IVtk packages functionality in DRAW.

- it allows to create VTK interactive view in regular or virtual mode (virtual windows),
  display OCC objects and dump them.

- TKIVtkDraw provides also test commands: ivtlinit, ivtkdisplay, ivtkerase, ivtksetdispmode,
   ivtksetselmode, ivtkmoveto, ivtkselect, ivtkfit, ivtkdump, ivtkbgcolor.

Corrected offscreen rendering mode.

Moved vinit command from /v3d/begin script to avoid unused occ view in ivtk tests.

src/OS/Draw.tcl

@@ -15,8 +15,15 @@
 ;# Liste des toolkits WOK sous forme de full path
 ;# 
 proc Draw:toolkits { } {
-    return [list TKDraw TKTopTest TKViewerTest TKXSDRAW TKDCAF TKXDEDRAW TKTObjDRAW TKQADraw]
+    set aResult [list TKDraw TKTopTest TKViewerTest TKXSDRAW TKDCAF TKXDEDRAW TKTObjDRAW TKQADraw]
+
+    if { $::env(HAVE_VTK) == "true" } {
+      lappend aResult "TKIVtkDraw"
+    }
+
+    return $aResult
 }
+
 ;#
 ;# Autres UDs a prendre. Listes de triplets
 ;# { ar typ UD str } Tous les types de UD vont dans un sous directory nomme root/str