import bpy, sys, math, mathutils
src, outdir = sys.argv[-2], sys.argv[-1]
bpy.ops.wm.read_factory_settings(use_empty=True)
bpy.ops.import_scene.gltf(filepath=src)
meshes = [o for o in bpy.data.objects if o.type == 'MESH']
# frame on the dominant mesh only — tiny helper meshes (attachment markers) inflate the bbox
if len(meshes) > 1:
    meshes = [max(meshes, key=lambda o: len(o.data.vertices))]
# bind pose: strip animation
for o in bpy.data.objects:
    if o.animation_data: o.animation_data_clear()
    if o.type == 'ARMATURE':
        for pb in o.pose.bones:
            pb.location = (0,0,0); pb.rotation_quaternion = (1,0,0,0); pb.rotation_euler = (0,0,0); pb.scale = (1,1,1)
bpy.context.view_layer.update()
mn = mathutils.Vector((1e9,)*3); mx = mathutils.Vector((-1e9,)*3)
for o in meshes:
    for v in o.bound_box:
        w = o.matrix_world @ mathutils.Vector(v)
        mn = mathutils.Vector(map(min, mn, w)); mx = mathutils.Vector(map(max, mx, w))
c = (mn + mx) / 2; h = (mx - mn).z; w_ = max((mx - mn).x, (mx - mn).y)
sc = bpy.context.scene
sc.render.engine = 'BLENDER_EEVEE'
sc.render.resolution_x = 1024; sc.render.resolution_y = 1024
sc.render.film_transparent = True
wld = bpy.data.worlds.new('w'); sc.world = wld; wld.use_nodes = True
wld.node_tree.nodes['Background'].inputs[0].default_value = (1,1,1,1)
wld.node_tree.nodes['Background'].inputs[1].default_value = 1.0
for name, dirv in (('front', mathutils.Vector((0,1,0))), ('back', mathutils.Vector((0,-1,0)))):
    cam = bpy.data.objects.new('cam_'+name, bpy.data.cameras.new('c'))
    cam.data.type = 'ORTHO'; cam.data.ortho_scale = h * 1.1
    bpy.context.collection.objects.link(cam)
    cam.location = c - dirv * (h * 2)
    cam.rotation_euler = dirv.to_track_quat('-Z','Y').to_euler()
    sc.camera = cam
    sc.render.filepath = f"{outdir}/base_{name}.png"
    bpy.ops.render.render(write_still=True)
    print('rendered', name)