def get_view_axis_in_scene_coordinates(view):
    import numpy
tform = view.scene.transform
w, h = view.canvas.size
screen_center = numpy.array([w / 2, h / 2, 0, 1])
d1 = numpy.array([0, 0, 1, 0])
point_in_front_of_screen_center = screen_center + d1
p1 = tform.imap(point_in_front_of_screen_center)
p0 = tform.imap(screen_center)
assert abs(p1[3] - 1.0) < 1e-05
assert abs(p0[3] - 1.0) < 1e-05
return p0[0:3], p1[0:3]
How to get world coordinates from screen coordinates in Vispy