puts "========"
puts "0031274: Data Exchange - RWObj_Reader ignores usemtl with empty name"
puts "========"

set material_mtl {newmtl Red
Kd 1.0 0.0 0.0
newmtl Green
Kd 0.0 1.0 0.0
newmtl Blue
Kd 0.0 0.0 1.0}

set ml_obj {
mtllib usemtl_material.mtl
v 0 0 0
v 2 0 0
v 2 1 0
v 1 2 0
v 0 1 0
v 0 0 2
v 2 0 2
v 2 1 2
v 1 2 2
v 0 1 2
g Red
usemtl Red
f 5 4 3 2 1
g Gren
usemtl Green
f 7 8 9 10 6
g Blue
usemtl Blue
f 10 9 4 5
g Gray
usemtl
f 9 8 3 4
f 6 10 5 1
f 2 3 8 7
f 1 2 7 6}

set fd [open ${imagedir}/${casename}_material.mtl w]
fconfigure $fd -translation lf
puts $fd $material_mtl
close $fd

set fd [open ${imagedir}/${casename}.obj w]
fconfigure $fd -translation lf
puts $fd $ml_obj
close $fd

ReadObj D ${imagedir}/${casename}.obj
XGetOneShape s D

explode s
set md [XGetVisMaterial D s_4]
if { [string trimright $md] != "EMPTY" } { puts "Error: EMPTY material is expected for last group" }