import math

import cadquery as cq
from cq_gears import SpurGear

# User Settings
lens_ring_diameter=100.0
lens_name=''
follow_focus_width=10.0

# Constants
follow_focus_mod=0.8
follow_focus_inner_thickness=5.0
follow_focus_num_teeth=int(math.ceil((follow_focus_inner_thickness+lens_ring_diameter)
                                     /follow_focus_mod))

# Create follow focus ring
ring = SpurGear(module=follow_focus_mod,
                teeth_number=follow_focus_num_teeth,
                width=follow_focus_width,
                bore_d=lens_ring_diameter)

# Render
wp = cq.Workplane('XY').gear(ring)
show_object(wp)

# Export STL
cq.exporters.export(wp, 'follow_focus_ring{}.stl'.format(lens_name))