Visualization - incorrect rectangular selection with clipping planes defining a box

pload XDE OCAF VISUALIZATION MODELING

ReadStep D "as1-oc-214.stp"
XGetOneShape S D

explode S So

vclear
vinit View1

#vdisplay -dispMode 1 S_10
vdisplay -dispMode 1 S_1 S_2 S_3 S_4 S_5 S_6 S_7 S_8 S_9 S_10 S_11 S_12 S_13 S_14 S_15 S_16 S_17 S_18
vfit

vclipplane create XMin
vclipplane change XMin equation 1.0 0.0 0.0 1.0e+001
vclipplane set XMin view Driver1/Viewer1/View1

vclipplane create XMax
vclipplane change XMax equation -1.0 -0.0 -0.0 1.603203e+002
vclipplane set XMax view Driver1/Viewer1/View1

vclipplane create YMin
vclipplane change YMin equation 0.0 1.0 0.0 -6.537673e+001
vclipplane set YMin view Driver1/Viewer1/View1

vclipplane create YMax
vclipplane change YMax equation -0.0 -1.0 -0.0 1.50e+002
vclipplane set YMax view Driver1/Viewer1/View1

vclipplane create ZMin
vclipplane change ZMin equation 0.0 0.0 1.0 4.0
vclipplane set ZMin view Driver1/Viewer1/View1

vclipplane create ZMax
vclipplane change ZMax equation -0.0 -0.0 -1.0 8.0e+001
vclipplane set ZMax view Driver1/Viewer1/View1

set corners { {-1.0e[phone removed]e+001 -4.0} {1.603203e[phone removed]e+001 -4.0} {-1.0e+001 1.50e+002 -4.0} {1.603203e+002 1.50e+002 -4.0} {-1.0e[phone removed]e+001 8.0e+001} {1.603203e[phone removed]e+001 8.0e+001} {-1.0e+001 1.50e+002 8.0e+001} {1.603203e+002 1.50e+002 8.0e+001} }
foreach c ${corners} {
  set X [lindex $c 0]
  set Y [lindex $c 1]
  set Z [lindex $c 2]
  set ret [vconvert $X $Y $Z window]
  set p [lindex [split $ret ":"] 1]
  lappend x [lindex $p 0] 
  lappend y [lindex $p 1]
}
set x [join $x ","]
set y [join $y ","]
set xmin [expr min($x)]
set ymin [expr min($y)]
set xmax [expr max($x)]
set ymax [expr max($y)]

vselect $xmin $ymin $xmax $ymax

vnbselected