bumo 0.1.2

BUild123d Mutables Objects

Bumo

BUild123d Mutables Objects

An experimental package used to manage Build123d objects by applying mutations on them.

It can be used:

• just out of curiosity, because it's a new way to build things;
• as a debug tool, using colors and debug mode;
• as a more object-oriented approach to build CAD parts.

Installation

This package is registred on Pypi, so you can either install it with Poetry:

poetry add bumo

or with pip:

pip install bumo

Getting started

Bumo is not a cad library on its own and does not aim to replace Build123d, you should take a look at the Build123d docs before using it.

Note: In the following examples we will use ocp vscode, but any other viewer should work.

Instantiating the builder

First things first, let's instanciate a Bumo builder and pass a Build123d part into it. Note that we must call the object (obj()) when passing it to the show function.

import build123d as _
from ocp_vscode import show_object
from bumo import Builder

obj = Builder(_.Box(12, 12, 2))

show_object(obj(), clear=True)

Adding mutations

When applying an operation, instead of returning a copy of the modified object, the builder mutates the object:

obj = Builder(_.Box(12, 12, 2))
obj.add(_.Box(8, 8, 4))
obj.sub(_.Cylinder(3, 4))

Note that you can also pass an other builder to a mutation:

obj = Builder(_.Box(12, 12, 2))
obj2 = Builder(_.Box(8, 8, 4))
obj.add(obj2)
obj.sub(_.Cylinder(3, 4))

Changing colors

On each mutation you can pass a specific color instead of the auto-generated-one:

obj = Builder(_.Box(12, 12, 2), "orange")
obj.add(_.Box(8, 8, 4), "green")
obj.sub(_.Cylinder(3, 4), "violet")

Listing mutations

You can print the list of mutations and their properties:

obj.info()

The previous example will produce:

╒═══════╤═══════════╤═════════╤═════════╕
│   Idx │ Id        │ Type    │ Color   │
╞═══════╪═══════════╪═════════╪═════════╡
│     0 │ Builder-0 │ Builder │ orange  │
├───────┼───────────┼─────────┼─────────┤
│     1 │ add-1     │ add     │ green   │
├───────┼───────────┼─────────┼─────────┤
│     2 │ sub-2     │ sub     │ violet  │
╘═══════╧═══════════╧═════════╧═════════╛

Moving objects

You can move objects with move(), all colors will be preserved. Note that you can still use the Build123d * operator before passing the object to the builder.

obj = Builder(_.Box(12, 12, 2))
obj.add(_.Box(8, 8, 4))
obj.move(_.Location([-5, 2, 0]))
obj.sub(_.Rotation(25, 25, 0) * _.Cylinder(2.5, 10))

Alternative syntax

Alternatively you can use the operators +=, -=, &=, *= to add mutations (but passing a color or debug mode will not be possible):

obj = Builder(_.Box(12, 12, 2))
obj += _.Box(8, 8, 4) # fuse
obj -= _.Cylinder(3, 4) # substract
obj &= _.Cylinder(5, 4) # intersect
obj *= _.Rotation(90) # move

Note that their counterpart +, -, &, * are not allowed.

Reusing mutations

Instead of returning a copy of the object, mutations return a Mutation object that can be used to retrieve the altered faces and edges. Mutations can also be accessed by querrying a builder index (ie. obj[n]). This is useful with fillets and chamfers:

obj = Builder(_.Box(12, 12, 2))
obj.add(_.Box(8, 8, 4))
obj.fillet(obj[-1].edges_added(), 0.4)
hole = obj.sub(_.Cylinder(3, 4))
obj.chamfer(hole.edges_added()[0], 0.3)

Using the debug mode

You can turn one or several mutations in debug mode, so all the other faces will be translucent. Either by passing a debug attribute to mutations, or passing faces (even removed ones) to the debug method:

obj = Builder(_.Box(12, 12, 2))
obj.add(_.Box(8, 8, 4))
obj.fillet(obj[-1].edges_added(), 0.4)
hole = obj.sub(_.Cylinder(3, 4))
obj.chamfer(hole.edges_added()[0], 0.3, debug=True)
obj.debug(obj[2].faces_altered()[0], "red")
# obj.debug(hole.faces_removed(), "red")

Configuring the builder

You can set builder attributes if necessary:

Builder.default_color = "grey"
Builder.debug_alpha = 0.5
Builder.autocolor = False
Builder.color_palette = ColorPalette.INFERNO