CadQuery object filtering framework
cq-filter adds a few new workplane methods that take a function argument
of type f: Callable[[CQObject], bool]
:
-
filter(f)
: filters Workplane objects -
sort(f)
: orders Workplane objects -
group(f)
: groups Workplane objects -
last
: selects newly created faces -
toWires
: select wires from selected faces
Additionally, it adds subscription support to the Workplane, allowing selection of objects quickly.
Rationale
Manipulating object selections in cadquery isn't currently possible without breaking out of the fluent API.
Using filter
Following example filters all faces with an Area of more than 100
wp = (
wp
.faces(">Z")
.filter(lambda face: face.Area() > 100)
)
>= 100
, but upon
closer inspection it turns out the area is actually just slightly below 100 (99.999999997). Consider rounding to some
sane precision, like round(face.Area(), 4)
Using sort and subscription
Following example sorts all faces by area and selects the three biggest ones
wp = (
wp
.faces(">Z")
.sort(lambda face: face.Area())[-3:]
)
Using group and clustering
Select the smallest faces that are within 10 units of each other
wp = (
wp
.faces(">Z")
.group(Cluster(lambda face: face.Area(), tol=10)[0])
)
-
⚠️ group()
call will not yet select new objects, but it will create a new workplane object. Selection should be done immediatelly after the grouping. Grouping data will be erased by next manipulation of workplane. -
selecting a range of groups (
[0:2]
) works as expected -
Cluster() defaults to a tolerance of
1e-4
last
to select newly created faces
Using A call to .last(everything=False)
attempts to select newly created faces. When everything = False
it will only
select faces that share all their edges with other new faces. In other words: probably the face you'd want to focus on
after some operation like extrude, cut or revolve will be selected.
Supplying everything = True
will select all faces that are new.
from cq_filter import Workplane
wp = (
Workplane()
.rect(5, 5)
.extrude(2)
.last()
.workplane()
)
-
⚠️ last
will not select faces that were modified
Usage
You may want to create your own workplane class if you have multiple mixins
from cq_filter import CQFilterMixin
class Workplane(CQFilterMixin, cq.Workplane):
pass
If you don't have multiple mixins, then the above class can also be directly imported
from cq_filter import Workplane