cadquery-freecad-module/cadquery/selectors.py
2016-06-02 21:49:15 +02:00

541 lines
17 KiB
Python

"""
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/>
"""
import re
import math
from cadquery import Vector,Edge,Vertex,Face,Solid,Shell,Compound
class Selector(object):
"""
Filters a list of objects
Filters must provide a single method that filters objects.
"""
def filter(self,objectList):
"""
Filter the provided list
:param objectList: list to filter
:type objectList: list of FreeCAD primatives
:return: filtered list
The default implementation returns the original list unfiltered
"""
return 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)
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
"""
def __init__(self,pnt ):
self.pnt = pnt
def filter(self,objectList):
def dist(tShape):
return tShape.Center().sub(Vector(*self.pnt)).Length
#if tShape.ShapeType == 'Vertex':
# return tShape.Point.sub(toVector(self.pnt)).Length
#else:
# return tShape.CenterOfMass.sub(toVector(self.pnt)).Length
return [ min(objectList,key=dist) ]
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
def filter(self, objectList):
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
class BaseDirSelector(Selector):
"""
A selector that handles selection on the basis of a single
direction vector
"""
def __init__(self,vector,tolerance=0.0001 ):
self.direction = vector
self.TOLERANCE = tolerance
def test(self,vec):
"Test a specified vector. Subclasses override to provide other implementations"
return True
def filter(self,objectList):
"""
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 type(o) == Face:
# a face is only parallell to a direction if it is a plane, and its normal is parallel to the dir
normal = o.normalAt(None)
if self.test(normal):
r.append(o)
elif type(o) == Edge and o.geomType() == 'LINE':
#an edge is parallel to a direction if it is a line, and the line is parallel to the dir
tangent = o.tangentAt(None)
if self.test(tangent):
r.append(o)
return r
class ParallelDirSelector(BaseDirSelector):
"""
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 a normals in the z direction, and is equivalent to::
CQ(aCube).faces("|Z")
"""
def test(self,vec):
return self.direction.cross(vec).Length < self.TOLERANCE
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 a normals in the z direction, and is equivalent to::
CQ(aCube).faces("+Z")
"""
def test(self,vec):
return abs(self.direction.getAngle(vec) < self.TOLERANCE)
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 a normals perpendicular to the z direction, and is equivalent to::
CQ(aCube).faces("#Z")
"""
def test(self,vec):
angle = self.direction.getAngle(vec)
r = (abs(angle) < self.TOLERANCE) or (abs(angle - math.pi) < self.TOLERANCE )
return not r
class TypeSelector(Selector):
"""
Selects objects of the prescribed topological type.
Applicability:
Faces: Plane,Cylinder,Sphere
Edges: Line,Circle,Arc
You can use the shortcut selector %(PLANE|SPHERE|CONE) for faces,
and %(LINE|ARC|CIRCLE) for edges.
For example this::
CQ(aCube).faces ( TypeSelector("PLANE") )
will select 6 faces, and is equivalent to::
CQ(aCube).faces( "%PLANE" )
"""
def __init__(self,typeString):
self.typeString = typeString.upper()
def filter(self,objectList):
r = []
for o in objectList:
if o.geomType() == self.typeString:
r.append(o)
return r
class DirectionMinMaxSelector(Selector):
"""
Selects objects closest or farthest in the specified direction
Used for faces, points, and edges
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" )
Future Enhancements:
provide a nicer way to select in arbitrary directions. IE, a bit more code could
allow '>(0,0,1)' to work.
"""
def __init__(self, vector, directionMax=True, tolerance=0.0001):
self.vector = vector
self.max = max
self.directionMax = directionMax
self.TOLERANCE = tolerance
def filter(self,objectList):
def distance(tShape):
return tShape.Center().dot(self.vector)
#if tShape.ShapeType == 'Vertex':
# pnt = tShape.Point
#else:
# pnt = tShape.Center()
#return pnt.dot(self.vector)
# import OrderedDict
from collections import OrderedDict
#make and distance to object dict
objectDict = {distance(el) : el for el in objectList}
#transform it into an ordered dict
objectDict = OrderedDict(sorted(objectDict.items(),
key=lambda x: x[0]))
# find out the max/min distance
if self.directionMax:
d = objectDict.keys()[-1]
else:
d = objectDict.keys()[0]
# return all objects at the max/min distance (within a tolerance)
return filter(lambda o: abs(d - distance(o)) < self.TOLERANCE, objectList)
class DirectionNthSelector(Selector):
"""
Selects objects closest or farthest in the specified direction
Used for faces, points, and edges
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" )
Future Enhancements:
provide a nicer way to select in arbitrary directions. IE, a bit more code could
allow '>(0,0,1)' to work.
"""
def __init__(self, vector, n, directionMax=True, tolerance=0.0001):
self.vector = vector
self.max = max
self.directionMax = directionMax
self.TOLERANCE = tolerance
if directionMax:
self.N = n
else:
self.N = -n
def filter(self,objectList):
def distance(tShape):
return tShape.Center().dot(self.vector)
#if tShape.ShapeType == 'Vertex':
# pnt = tShape.Point
#else:
# pnt = tShape.Center()
#return pnt.dot(self.vector)
#make and distance to object dict
objectDict = {distance(el) : el for el in objectList}
#calculate how many digits of precision do we need
digits = int(1/self.TOLERANCE)
# create a rounded distance to original distance mapping (implicitly perfroms unique operation)
dist_round_dist = {round(d,digits) : d for d in objectDict.keys()}
# choose the Nth unique rounded distance
nth_d = dist_round_dist[sorted(dist_round_dist.keys())[self.N]]
# map back to original objects and return
return [objectDict[d] for d in objectDict.keys() if abs(d-nth_d) < self.TOLERANCE]
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
def filter(self, objectList):
return self.filterResults(self.left.filter(objectList),
self.right.filter(objectList))
def filterResults(self, r_left, r_right):
raise NotImplementedError
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))
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))
class SubtractSelector(BinarySelector):
"""
Difference selector. Substract results of a selector from another
selectors results.
"""
def filterResults(self, r_left, r_right):
return list(set(r_left) - set(r_right))
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
def filter(self, objectList):
# note that Selector() selects everything
return SubtractSelector(Selector(), self.selector).filter(objectList)
class StringSyntaxSelector(Selector):
"""
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
***Modfiers*** 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``
Selectors are a complex topic: see :ref:`selector_reference` for more information
"""
def __init__(self,selectorString):
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)
}
namedViews = {
'front': ('>','Z' ),
'back': ('<','Z'),
'left':('<', 'X'),
'right': ('>', 'X'),
'top': ('>','Y'),
'bottom': ('<','Y')
}
self.selectorString = selectorString
r = re.compile("\s*([-\+<>\|\%#])*\s*(\w+)\s*",re.IGNORECASE)
m = r.match(selectorString)
if m != None:
if namedViews.has_key(selectorString):
(a,b) = namedViews[selectorString]
self.mySelector = self._chooseSelector(a,b )
else:
self.mySelector = self._chooseSelector(m.groups()[0],m.groups()[1])
else:
raise ValueError ("Selector String format must be [-+<>|#%] X|Y|Z ")
def _chooseSelector(self,selType,selAxis):
"""Sets up the underlying filters accordingly"""
if selType == "%":
return TypeSelector(selAxis)
#all other types need to select axis as a vector
#get the axis vector first, will throw an except if an unknown axis is used
try:
vec = self.axes[selAxis]
except KeyError:
raise ValueError ("Axis value %s not allowed: must be one of %s" % (selAxis, str(self.axes)))
if selType in (None, "+"):
#use direction filter
return DirectionSelector(vec)
elif selType == '-':
#just use the reverse of the direction vector
return DirectionSelector(vec.multiply(-1.0))
elif selType == "|":
return ParallelDirSelector(vec)
elif selType == ">":
return DirectionMinMaxSelector(vec,True)
elif selType == "<":
return DirectionMinMaxSelector(vec,False)
elif selType == '#':
return PerpendicularDirSelector(vec)
else:
raise ValueError ("Selector String format must be [-+<>|] X|Y|Z ")
def filter(self,objectList):
"""
selects minimum, maximum, positive or negative values relative to a direction
[+\|-\|<\|>\|] \<X\|Y\|Z>
"""
return self.mySelector.filter(objectList)