OCCT

puts "========"
puts "OCC165"
puts "Bug regression in BRepOffsetAPI_MakeOffset class (offsetting in OY direction)"
puts "========"

restore [locate_data_file offset_wire_019.brep] a 
checkshape a

mkplane f a
checkshape f

if [catch {mkoffset res1 f 1 1 } result] {
  puts "Faulty OCC165 (case 1) : function MKOFFSET works wrongly"
} else {
  puts "OCC165 OK (case 1): function MKOFFSET works properly"
  checkshape res1_1
  mkplane pl1 res1_1
  checkshape pl1
}

if [catch {mkoffset res2 f 1 -1 } result] {
  puts "Faulty OCC165 (case 2) : function MKOFFSET works wrongly"
} else {
  puts "OCC165 OK (case 2): function MKOFFSET works properly"
  checkshape res2_1
  mkplane pl2 res2_1 
  checkshape pl2
}

compound a res1_1 res2_1 res
checkprops res1_1 -l 1088.43
checkprops res2_1 -l 1075.87