cadquery-freecad-module/ThirdParty/cqparts_fasteners/fasteners/screw.py

53 lines
1.9 KiB
Python

from cqparts.constraint import Mate, Coincident
from .base import Fastener
from ..screws import Screw
from ..utils import VectorEvaluator, Selector, Applicator
class ScrewFastener(Fastener):
"""
Screw fastener assembly.
Example usage can be found here: :ref:`cqparts_fasteners.built-in.screw`
"""
Evaluator = VectorEvaluator
class Selector(Selector):
ratio = 0.8
def get_components(self):
end_effect = self.evaluator.eval[-1]
end_point = end_effect.start_point + (end_effect.end_point - end_effect.start_point) * self.ratio
return {'screw': Screw(
head=('countersunk', {
'diameter': 9.5,
'height': 3.5,
}),
neck_length=abs(self.evaluator.eval[-1].start_point - self.evaluator.eval[0].start_point),
# only the length after the neck is threaded
length=abs(end_point - self.evaluator.eval[0].start_point),
#length=abs(self.evaluator.eval[-1].end_point - self.evaluator.eval[0].start_point),
)}
def get_constraints(self):
# bind fastener relative to its anchor; the part holding it in.
anchor_part = self.evaluator.eval[-1].part # last effected part
return [Coincident(
self.components['screw'].mate_origin,
Mate(anchor_part, self.evaluator.eval[0].start_coordsys - anchor_part.world_coords)
)]
class Applicator(Applicator):
def apply_alterations(self):
screw = self.selector.components['screw']
cutter = screw.make_cutter() # cutter in local coords
for effect in self.evaluator.eval:
relative_coordsys = screw.world_coords - effect.part.world_coords
local_cutter = relative_coordsys + cutter
effect.part.local_obj = effect.part.local_obj.cut(local_cutter)