Source code for cadquery.selectors

"""
    Copyright (C) 2011-2015  Parametric Products Intellectual Holdings, LLC

    This file is part of CadQuery.

    CadQuery is free software; you can redistribute it and/or
    modify it under the terms of the GNU Lesser General Public
    License as published by the Free Software Foundation; either
    version 2.1 of the License, or (at your option) any later version.

    CadQuery is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
    Lesser General Public License for more details.

    You should have received a copy of the GNU Lesser General Public
    License along with this library; If not, see <http://www.gnu.org/licenses/>
"""

from abc import abstractmethod, ABC
import math
from .occ_impl.geom import Vector
from .occ_impl.shape_protocols import (
    ShapeProtocol,
    Shape1DProtocol,
    FaceProtocol,
    geom_LUT_EDGE,
    geom_LUT_FACE,
)
from pyparsing import (
    pyparsing_common,
    Literal,
    Word,
    nums,
    Optional,
    Combine,
    oneOf,
    Group,
    infixNotation,
    opAssoc,
)
from functools import reduce
from typing import Iterable, List, Sequence, TypeVar, cast

Shape = TypeVar("Shape", bound=ShapeProtocol)


[docs]class Selector(object): """ Filters a list of objects. Filters must provide a single method that filters objects. """
[docs] def filter(self, objectList: Sequence[Shape]) -> List[Shape]: """ Filter the provided list. The default implementation returns the original list unfiltered. :param objectList: list to filter :type objectList: list of OCCT primitives :return: filtered list """ return list(objectList)
def __and__(self, other): return AndSelector(self, other) def __add__(self, other): return SumSelector(self, other) def __sub__(self, other): return SubtractSelector(self, other) def __neg__(self): return InverseSelector(self)
[docs]class NearestToPointSelector(Selector): """ Selects object nearest the provided point. If the object is a vertex or point, the distance is used. For other kinds of shapes, the center of mass is used to to compute which is closest. Applicability: All Types of Shapes Example:: CQ(aCube).vertices(NearestToPointSelector((0, 1, 0))) returns the vertex of the unit cube closest to the point x=0,y=1,z=0 """
[docs] def __init__(self, pnt): self.pnt = pnt
[docs] def filter(self, objectList: Sequence[Shape]): def dist(tShape): return tShape.Center().sub(Vector(*self.pnt)).Length return [min(objectList, key=dist)]
[docs]class BoxSelector(Selector): """ Selects objects inside the 3D box defined by 2 points. If `boundingbox` is True only the objects that have their bounding box inside the given box is selected. Otherwise only center point of the object is tested. Applicability: all types of shapes Example:: CQ(aCube).edges(BoxSelector((0, 1, 0), (1, 2, 1))) """ def __init__(self, point0, point1, boundingbox=False): self.p0 = Vector(*point0) self.p1 = Vector(*point1) self.test_boundingbox = boundingbox
[docs] def filter(self, objectList: Sequence[Shape]): result = [] x0, y0, z0 = self.p0.toTuple() x1, y1, z1 = self.p1.toTuple() def isInsideBox(p): # using XOR for checking if x/y/z is in between regardless # of order of x/y/z0 and x/y/z1 return ( ((p.x < x0) ^ (p.x < x1)) and ((p.y < y0) ^ (p.y < y1)) and ((p.z < z0) ^ (p.z < z1)) ) for o in objectList: if self.test_boundingbox: bb = o.BoundingBox() if isInsideBox(Vector(bb.xmin, bb.ymin, bb.zmin)) and isInsideBox( Vector(bb.xmax, bb.ymax, bb.zmax) ): result.append(o) else: if isInsideBox(o.Center()): result.append(o) return result
[docs]class BaseDirSelector(Selector): """ A selector that handles selection on the basis of a single direction vector. """ def __init__(self, vector: Vector, tolerance: float = 0.0001): self.direction = vector self.tolerance = tolerance
[docs] def test(self, vec: Vector) -> bool: "Test a specified vector. Subclasses override to provide other implementations" return True
[docs] def filter(self, objectList: Sequence[Shape]) -> List[Shape]: """ There are lots of kinds of filters, but for planes they are always based on the normal of the plane, and for edges on the tangent vector along the edge """ r = [] for o in objectList: # no really good way to avoid a switch here, edges and faces are simply different! if o.ShapeType() == "Face" and o.geomType() == "PLANE": # a face is only parallel to a direction if it is a plane, and # its normal is parallel to the dir test_vector = cast(FaceProtocol, o).normalAt(None) elif o.ShapeType() == "Edge" and o.geomType() == "LINE": # an edge is parallel to a direction if its underlying geometry is plane or line test_vector = cast(Shape1DProtocol, o).tangentAt() else: continue if self.test(test_vector): r.append(o) return r
[docs]class ParallelDirSelector(BaseDirSelector): r""" Selects objects parallel with the provided direction. Applicability: Linear Edges Planar Faces Use the string syntax shortcut \|(X|Y|Z) if you want to select based on a cardinal direction. Example:: CQ(aCube).faces(ParallelDirSelector((0, 0, 1))) selects faces with the normal parallel to the z direction, and is equivalent to:: CQ(aCube).faces("|Z") """
[docs] def test(self, vec: Vector) -> bool: return self.direction.cross(vec).Length < self.tolerance
[docs]class DirectionSelector(BaseDirSelector): """ Selects objects aligned with the provided direction. Applicability: Linear Edges Planar Faces Use the string syntax shortcut +/-(X|Y|Z) if you want to select based on a cardinal direction. Example:: CQ(aCube).faces(DirectionSelector((0, 0, 1))) selects faces with the normal in the z direction, and is equivalent to:: CQ(aCube).faces("+Z") """
[docs] def test(self, vec: Vector) -> bool: return self.direction.getAngle(vec) < self.tolerance
[docs]class PerpendicularDirSelector(BaseDirSelector): """ Selects objects perpendicular with the provided direction. Applicability: Linear Edges Planar Faces Use the string syntax shortcut #(X|Y|Z) if you want to select based on a cardinal direction. Example:: CQ(aCube).faces(PerpendicularDirSelector((0, 0, 1))) selects faces with the normal perpendicular to the z direction, and is equivalent to:: CQ(aCube).faces("#Z") """
[docs] def test(self, vec: Vector) -> bool: return abs(self.direction.getAngle(vec) - math.pi / 2) < self.tolerance
[docs]class TypeSelector(Selector): """ Selects objects having the prescribed geometry type. Applicability: Faces: PLANE, CYLINDER, CONE, SPHERE, TORUS, BEZIER, BSPLINE, REVOLUTION, EXTRUSION, OFFSET, OTHER Edges: LINE, CIRCLE, ELLIPSE, HYPERBOLA, PARABOLA, BEZIER, BSPLINE, OFFSET, OTHER You can use the string selector syntax. For example this:: CQ(aCube).faces(TypeSelector("PLANE")) will select 6 faces, and is equivalent to:: CQ(aCube).faces("%PLANE") """
[docs] def __init__(self, typeString: str): self.typeString = typeString.upper()
[docs] def filter(self, objectList: Sequence[Shape]) -> List[Shape]: r = [] for o in objectList: if o.geomType() == self.typeString: r.append(o) return r
class _NthSelector(Selector, ABC): """ An abstract class that provides the methods to select the Nth object/objects of an ordered list. """ def __init__(self, n: int, directionMax: bool = True, tolerance: float = 0.0001): self.n = n self.directionMax = directionMax self.tolerance = tolerance def filter(self, objectlist: Sequence[Shape]) -> List[Shape]: """ Return the nth object in the objectlist sorted by self.key and clustered if within self.tolerance. """ if len(objectlist) == 0: # nothing to filter raise ValueError("Can not return the Nth element of an empty list") clustered = self.cluster(objectlist) if not self.directionMax: clustered.reverse() try: out = clustered[self.n] except IndexError: raise IndexError( f"Attempted to access index {self.n} of a list with length {len(clustered)}" ) return out @abstractmethod def key(self, obj: Shape) -> float: """ Return the key for ordering. Can raise a ValueError if obj can not be used to create a key, which will result in obj being dropped by the clustering method. """ raise NotImplementedError def cluster(self, objectlist: Sequence[Shape]) -> List[List[Shape]]: """ Clusters the elements of objectlist if they are within tolerance. """ key_and_obj = [] for obj in objectlist: # Need to handle value errors, such as what occurs when you try to # access the radius of a straight line try: key = self.key(obj) except ValueError: # forget about this element and continue continue key_and_obj.append((key, obj)) key_and_obj.sort(key=lambda x: x[0]) clustered = [[]] # type: List[List[Shape]] start = key_and_obj[0][0] for key, obj in key_and_obj: if abs(key - start) <= self.tolerance: clustered[-1].append(obj) else: clustered.append([obj]) start = key return clustered
[docs]class RadiusNthSelector(_NthSelector): """ Select the object with the Nth radius. Applicability: All Edge and Wires. Will ignore any shape that can not be represented as a circle or an arc of a circle. """
[docs] def key(self, obj: Shape) -> float: if obj.ShapeType() in ("Edge", "Wire"): return cast(Shape1DProtocol, obj).radius() else: raise ValueError("Can not get a radius from this object")
[docs]class CenterNthSelector(_NthSelector): """ Sorts objects into a list with order determined by the distance of their center projected onto the specified direction. Applicability: All Shapes. """ def __init__( self, vector: Vector, n: int, directionMax: bool = True, tolerance: float = 0.0001, ): super().__init__(n, directionMax, tolerance) self.direction = vector
[docs] def key(self, obj: Shape) -> float: return obj.Center().dot(self.direction)
[docs]class DirectionMinMaxSelector(CenterNthSelector): """ Selects objects closest or farthest in the specified direction. Applicability: All object types. for a vertex, its point is used. for all other kinds of objects, the center of mass of the object is used. You can use the string shortcuts >(X|Y|Z) or <(X|Y|Z) if you want to select based on a cardinal direction. For example this:: CQ(aCube).faces(DirectionMinMaxSelector((0, 0, 1), True)) Means to select the face having the center of mass farthest in the positive z direction, and is the same as:: CQ(aCube).faces(">Z") """
[docs] def __init__( self, vector: Vector, directionMax: bool = True, tolerance: float = 0.0001 ): super().__init__( n=-1, vector=vector, directionMax=directionMax, tolerance=tolerance )
# inherit from CenterNthSelector to get the CenterNthSelector.key method
[docs]class DirectionNthSelector(ParallelDirSelector, CenterNthSelector): """ Filters for objects parallel (or normal) to the specified direction then returns the Nth one. Applicability: Linear Edges Planar Faces """ def __init__( self, vector: Vector, n: int, directionMax: bool = True, tolerance: float = 0.0001, ): ParallelDirSelector.__init__(self, vector, tolerance) _NthSelector.__init__(self, n, directionMax, tolerance)
[docs] def filter(self, objectlist: Sequence[Shape]) -> List[Shape]: objectlist = ParallelDirSelector.filter(self, objectlist) objectlist = _NthSelector.filter(self, objectlist) return objectlist
[docs]class LengthNthSelector(_NthSelector): """ Select the object(s) with the Nth length Applicability: All Edge and Wire objects """
[docs] def key(self, obj: Shape) -> float: if obj.ShapeType() in ("Edge", "Wire"): return cast(Shape1DProtocol, obj).Length() else: raise ValueError( f"LengthNthSelector supports only Edges and Wires, not {type(obj).__name__}" )
[docs]class AreaNthSelector(_NthSelector): """ Selects the object(s) with Nth area Applicability: - Faces, Shells, Solids - Shape.Area() is used to compute area - closed planar Wires - a temporary face is created to compute area Will ignore non-planar or non-closed wires. Among other things can be used to select one of the nested coplanar wires or faces. For example to create a fillet on a shank:: result = ( cq.Workplane("XY") .circle(5) .extrude(2) .circle(2) .extrude(10) .faces(">Z[-2]") .wires(AreaNthSelector(0)) .fillet(2) ) Or to create a lip on a case seam:: result = ( cq.Workplane("XY") .rect(20, 20) .extrude(10) .edges("|Z or <Z") .fillet(2) .faces(">Z") .shell(2) .faces(">Z") .wires(AreaNthSelector(-1)) .toPending() .workplane() .offset2D(-1) .extrude(1) .faces(">Z[-2]") .wires(AreaNthSelector(0)) .toPending() .workplane() .cutBlind(2) ) """
[docs] def key(self, obj: Shape) -> float: if obj.ShapeType() in ("Face", "Shell", "Solid"): return obj.Area() elif obj.ShapeType() == "Wire": try: from cadquery.occ_impl.shapes import Face, Wire return abs(Face.makeFromWires(cast(Wire, obj)).Area()) except Exception as ex: raise ValueError( f"Can not compute area of the Wire: {ex}. AreaNthSelector supports only closed planar Wires." ) else: raise ValueError( f"AreaNthSelector supports only Wires, Faces, Shells and Solids, not {type(obj).__name__}" )
[docs]class BinarySelector(Selector): """ Base class for selectors that operates with two other selectors. Subclass must implement the :filterResults(): method. """ def __init__(self, left, right): self.left = left self.right = right
[docs] def filter(self, objectList: Sequence[Shape]): return self.filterResults( self.left.filter(objectList), self.right.filter(objectList) )
def filterResults(self, r_left, r_right): raise NotImplementedError
[docs]class AndSelector(BinarySelector): """ Intersection selector. Returns objects that is selected by both selectors. """ def filterResults(self, r_left, r_right): # return intersection of lists return list(set(r_left) & set(r_right))
[docs]class SumSelector(BinarySelector): """ Union selector. Returns the sum of two selectors results. """ def filterResults(self, r_left, r_right): # return the union (no duplicates) of lists return list(set(r_left + r_right))
[docs]class SubtractSelector(BinarySelector): """ Difference selector. Subtract results of a selector from another selectors results. """ def filterResults(self, r_left, r_right): return list(set(r_left) - set(r_right))
[docs]class InverseSelector(Selector): """ Inverts the selection of given selector. In other words, selects all objects that is not selected by given selector. """ def __init__(self, selector): self.selector = selector
[docs] def filter(self, objectList: Sequence[Shape]): # note that Selector() selects everything return SubtractSelector(Selector(), self.selector).filter(objectList)
def _makeGrammar(): """ Define the simple string selector grammar using PyParsing """ # float definition point = Literal(".") plusmin = Literal("+") | Literal("-") number = Word(nums) integer = Combine(Optional(plusmin) + number) floatn = Combine(integer + Optional(point + Optional(number))) # vector definition lbracket = Literal("(") rbracket = Literal(")") comma = Literal(",") vector = Combine( lbracket + floatn("x") + comma + floatn("y") + comma + floatn("z") + rbracket, adjacent=False, ) # direction definition simple_dir = oneOf(["X", "Y", "Z", "XY", "XZ", "YZ"]) direction = simple_dir("simple_dir") | vector("vector_dir") # CQ type definition cqtype = oneOf( set(geom_LUT_EDGE.values()) | set(geom_LUT_FACE.values()), caseless=True, ) cqtype = cqtype.setParseAction(pyparsing_common.upcaseTokens) # type operator type_op = Literal("%") # direction operator direction_op = oneOf([">", "<"]) # center Nth operator center_nth_op = oneOf([">>", "<<"]) # index definition ix_number = Group(Optional("-") + Word(nums)) lsqbracket = Literal("[").suppress() rsqbracket = Literal("]").suppress() index = lsqbracket + ix_number("index") + rsqbracket # other operators other_op = oneOf(["|", "#", "+", "-"]) # named view named_view = oneOf(["front", "back", "left", "right", "top", "bottom"]) return ( direction("only_dir") | (type_op("type_op") + cqtype("cq_type")) | (direction_op("dir_op") + direction("dir") + Optional(index)) | (center_nth_op("center_nth_op") + direction("dir") + Optional(index)) | (other_op("other_op") + direction("dir")) | named_view("named_view") ) _grammar = _makeGrammar() # make a grammar instance class _SimpleStringSyntaxSelector(Selector): """ This is a private class that converts a parseResults object into a simple selector object """ def __init__(self, parseResults): # define all token to object mappings self.axes = { "X": Vector(1, 0, 0), "Y": Vector(0, 1, 0), "Z": Vector(0, 0, 1), "XY": Vector(1, 1, 0), "YZ": Vector(0, 1, 1), "XZ": Vector(1, 0, 1), } self.namedViews = { "front": (Vector(0, 0, 1), True), "back": (Vector(0, 0, 1), False), "left": (Vector(1, 0, 0), False), "right": (Vector(1, 0, 0), True), "top": (Vector(0, 1, 0), True), "bottom": (Vector(0, 1, 0), False), } self.operatorMinMax = { ">": True, ">>": True, "<": False, "<<": False, } self.operator = { "+": DirectionSelector, "-": lambda v: DirectionSelector(-v), "#": PerpendicularDirSelector, "|": ParallelDirSelector, } self.parseResults = parseResults self.mySelector = self._chooseSelector(parseResults) def _chooseSelector(self, pr): """ Sets up the underlying filters accordingly """ if "only_dir" in pr: vec = self._getVector(pr) return DirectionSelector(vec) elif "type_op" in pr: return TypeSelector(pr.cq_type) elif "dir_op" in pr: vec = self._getVector(pr) minmax = self.operatorMinMax[pr.dir_op] if "index" in pr: return DirectionNthSelector( vec, int("".join(pr.index.asList())), minmax ) else: return DirectionMinMaxSelector(vec, minmax) elif "center_nth_op" in pr: vec = self._getVector(pr) minmax = self.operatorMinMax[pr.center_nth_op] if "index" in pr: return CenterNthSelector(vec, int("".join(pr.index.asList())), minmax) else: return CenterNthSelector(vec, -1, minmax) elif "other_op" in pr: vec = self._getVector(pr) return self.operator[pr.other_op](vec) else: args = self.namedViews[pr.named_view] return DirectionMinMaxSelector(*args) def _getVector(self, pr): """ Translate parsed vector string into a CQ Vector """ if "vector_dir" in pr: vec = pr.vector_dir return Vector(float(vec.x), float(vec.y), float(vec.z)) else: return self.axes[pr.simple_dir] def filter(self, objectList: Sequence[Shape]): r""" selects minimum, maximum, positive or negative values relative to a direction ``[+|-|<|>|] <X|Y|Z>`` """ return self.mySelector.filter(objectList) def _makeExpressionGrammar(atom): """ Define the complex string selector grammar using PyParsing (which supports logical operations and nesting) """ # define operators and_op = Literal("and") or_op = Literal("or") delta_op = oneOf(["exc", "except"]) not_op = Literal("not") def atom_callback(res): return _SimpleStringSyntaxSelector(res) # construct a simple selector from every matched atom.setParseAction(atom_callback) # define callback functions for all operations def and_callback(res): # take every secend items, i.e. all operands items = res.asList()[0][::2] return reduce(AndSelector, items) def or_callback(res): # take every secend items, i.e. all operands items = res.asList()[0][::2] return reduce(SumSelector, items) def exc_callback(res): # take every secend items, i.e. all operands items = res.asList()[0][::2] return reduce(SubtractSelector, items) def not_callback(res): right = res.asList()[0][1] # take second item, i.e. the operand return InverseSelector(right) # construct the final grammar and set all the callbacks expr = infixNotation( atom, [ (and_op, 2, opAssoc.LEFT, and_callback), (or_op, 2, opAssoc.LEFT, or_callback), (delta_op, 2, opAssoc.LEFT, exc_callback), (not_op, 1, opAssoc.RIGHT, not_callback), ], ) return expr _expression_grammar = _makeExpressionGrammar(_grammar)
[docs]class StringSyntaxSelector(Selector): r""" Filter lists objects using a simple string syntax. All of the filters available in the string syntax are also available ( usually with more functionality ) through the creation of full-fledged selector objects. see :py:class:`Selector` and its subclasses Filtering works differently depending on the type of object list being filtered. :param selectorString: A two-part selector string, [selector][axis] :return: objects that match the specified selector ***Modifiers*** are ``('|','+','-','<','>','%')`` :\|: parallel to ( same as :py:class:`ParallelDirSelector` ). Can return multiple objects. :#: perpendicular to (same as :py:class:`PerpendicularDirSelector` ) :+: positive direction (same as :py:class:`DirectionSelector` ) :-: negative direction (same as :py:class:`DirectionSelector` ) :>: maximize (same as :py:class:`DirectionMinMaxSelector` with directionMax=True) :<: minimize (same as :py:class:`DirectionMinMaxSelector` with directionMax=False ) :%: curve/surface type (same as :py:class:`TypeSelector`) ***axisStrings*** are: ``X,Y,Z,XY,YZ,XZ`` or ``(x,y,z)`` which defines an arbitrary direction It is possible to combine simple selectors together using logical operations. The following operations are supported :and: Logical AND, e.g. >X and >Y :or: Logical OR, e.g. \|X or \|Y :not: Logical NOT, e.g. not #XY :exc(ept): Set difference (equivalent to AND NOT): \|X exc >Z Finally, it is also possible to use even more complex expressions with nesting and arbitrary number of terms, e.g. (not >X[0] and #XY) or >XY[0] Selectors are a complex topic: see :ref:`selector_reference` for more information """
[docs] def __init__(self, selectorString): """ Feed the input string through the parser and construct an relevant complex selector object """ self.selectorString = selectorString parse_result = _expression_grammar.parseString(selectorString, parseAll=True) self.mySelector = parse_result.asList()[0]
[docs] def filter(self, objectList: Sequence[Shape]): """ Filter give object list through th already constructed complex selector object """ return self.mySelector.filter(objectList)