Shapes and Operations

Prev: Part 4: Creating Your First Component

This step dives into the core building blocks: shapes, transforms, and boolean operations. It also provides a reference-style walkthrough of each shape type.

Step 1 — Shapes (primitives)

PyMFCAD provides a compact set of primitives. All sizes are in pixels (x/y) and layers (z) unless noted.

Cube(size)

A rectangular block aligned to the axes.

cube = pymfcad.Cube((20, 10, 6))

Use cases: bulk volumes, straight channels, rectangular cutouts.

Cylinder(size)

A cylinder aligned on the Z‑axis. The size tuple defines diameter in X/Y and height in Z.

cyl = pymfcad.Cylinder((8, 8, 12))

Use cases: round vias, circular reservoirs, posts.

Sphere(size)

An ellipsoid. The size tuple defines the full extent in X/Y/Z.

sphere = pymfcad.Sphere((10, 10, 10))

Use cases: rounded terminations, smooth blending volumes.

RoundedCube(size, radius=...)

A cube with rounded edges.

rounded = pymfcad.RoundedCube((20, 10, 6), radius=2)

Use cases: channels with softer corners and smoother flow.

TextExtrusion(text, height, font_size, ...)

Extrudes 2D text into a 3D shape.

label = pymfcad.TextExtrusion("PyMFCAD", height=1, font_size=12)

Use cases: raised/engraved labels and quick “stamp” features.

ImportModel(path, ...)

Imports external geometry (e.g., GLB/STL) and converts it into a shape.

imported = pymfcad.ImportModel("fixtures/marker.glb")

Use cases: custom geometry, branding, or complex shapes.

TPMS(...)

Generates triply periodic minimal surface structures.

tpms = pymfcad.TPMS(
    size=(20, 20, 20),
    cells=(2, 2, 1),
    func=pymfcad.TPMS.gyroid,
    fill=0.0,
    refinement=10,
)

Key parameters:

  • size — unit cell size in px/layer space
  • cells — number of unit cells in X/Y/Z
  • func — TPMS function (e.g., gyroid, diamond, schwarz_p)
  • fill — level set value (isosurface at 0)
  • refinement — level set resolution

Use cases: lattices, porous regions, and advanced mixing structures.

Step 2 — Shape transforms

Every shape supports the same core transforms. Transforms can be chained.

translate((x, y, z))

Moves a shape by the given offset.

cube = pymfcad.Cube((10, 10, 5)).translate((5, 0, 2))

rotate((rx, ry, rz))

Rotates a shape in degrees about X, Y, and Z.

cube = pymfcad.Cube((10, 10, 5)).rotate((0, 0, 45))

resize((x, y, z))

Scales a shape to the target dimensions.

cube = pymfcad.Cube((10, 10, 5)).resize((20, 10, 5))

mirror((x, y, z))

Mirrors a shape across the requested axes. Use 1 to mirror on an axis and 0 to leave it unchanged.

cube = pymfcad.Cube((10, 10, 5)).mirror((1, 0, 0))

copy()

Creates a duplicate so you can transform independently.

cube = pymfcad.Cube((10, 10, 5))
copy = cube.copy().translate((15, 0, 0))

Step 3 — Boolean operations

Boolean operations combine shapes into more complex geometry.

Union (a + b)

shape = pymfcad.Cube((10, 10, 5)) + pymfcad.Sphere((8, 8, 8))

Difference (a - b)

shape = pymfcad.Cube((20, 20, 10)) - pymfcad.Cylinder((6, 6, 12))

Hull (a.hull(b))

Creates a smooth blend between two shapes.

shape = pymfcad.Sphere((6, 6, 6)).hull(pymfcad.Sphere((6, 6, 6)).translate((12, 0, 0)))

Step 4 — Putting it together

component = pymfcad.Component(size=(80, 60, 20), px_size=0.0076, layer_size=0.01)
component.add_label("bulk", pymfcad.Color.from_name("aqua", 127))
component.add_label("void", pymfcad.Color.from_name("red", 200))

bulk = pymfcad.RoundedCube((80, 60, 20), radius=2)
channel = pymfcad.Cylinder((6, 6, 24)).translate((40, 30, 10))

component.add_void("channel", channel, label="void")
component.add_bulk("bulk", bulk, label="bulk")
component.preview()

Next

Next: Part 6: Parametric Design