Module openscad_py.polyhedron
Classes
class Polyhedron (points: List[list | Point],
faces: List[list],
convexity: int = 10)-
A 3D primitive, a polyhedron defined by a list of points and faces. Nonplanar faces will be triangulated by OpenSCAD.
See https://en.wikibooks.org/wiki/OpenSCAD_User_Manual/The_OpenSCAD_Language#polyhedron
Arguments
- points: a list of Point objects or coordinate tuples defining the vertices
- faces: defines the faces as a list of lists of vertex indices. The points of a face must be listed clockwise when looking at the face from the outside inward.
Expand source code
class Polyhedron(Object): """A 3D primitive, a polyhedron defined by a list of points and faces. Nonplanar faces will be triangulated by OpenSCAD. See https://en.wikibooks.org/wiki/OpenSCAD_User_Manual/The_OpenSCAD_Language#polyhedron """ def __init__(self, points: List[TUnion[list, Point]], faces: List[list], convexity: int = 10): """ Arguments: - points: a list of Point objects or coordinate tuples defining the vertices - faces: defines the faces as a list of lists of vertex indices. The points of a face must be listed clockwise when looking at the face from the outside inward. """ self.points = [Point.c(p) for p in points] self.faces = faces self.convexity = convexity @classmethod def torus(cls, points: List[List[TUnion[list, Point]]], torus_connect_offset: int = 0, convexity: int = 10): """Construct a torus-like polyhedron from a 2D array of points. Each row of points must be oriented clockwise when looking from the first row (loop) toward the next. The rows of points form loops. Arguments: - points: A 2D array of points - torus_connect_offset: int, Whether to shift which points are connected in a torus in the last segment - convexity: int, see OpensCAD """ return cls.tube(points=points, convexity=convexity, make_torus=True, torus_connect_offset=torus_connect_offset) @classmethod def tube(cls, points: List[List[TUnion[list, Point]]], make_torus: bool = False, torus_connect_offset: int = 0, convexity: int = 10): """Construct a tube-like polyhedron from a 2D array of points. Each row of points must be oriented clockwise when looking at the pipe at the start inwards. The rows of points form loops. Arguments: - points: A 2D array of points - make_torus: bool, Whether to create a torus-like shape instead of a pipe with ends - torus_connect_offset: int, Whether to shift which points are connected in a torus in the last segment - convexity: int, see OpensCAD """ rows = len(points) row_len = len(points[0]) point_list = [] point_map = {} # { (row_ix,col_ix) -> list_ix, ... for row_ix, row in enumerate(points): for col_ix, point in enumerate(row): point_map[(row_ix, col_ix)] = len(point_list) point_list.append(point) faces = [] # Side faces for row_ix in range(1, rows): for col_ix in range(1, row_len): faces.append([ point_map[(row_ix, col_ix-1)], point_map[(row_ix, col_ix)], point_map[(row_ix-1, col_ix)], point_map[(row_ix-1, col_ix-1)] ]) faces.append([ point_map[(row_ix, row_len-1)], point_map[(row_ix, 0)], point_map[(row_ix-1, 0)], point_map[(row_ix-1, row_len-1)] ]) if not make_torus: # Starting cap faces.append([point_map[(0,x)] for x in range(row_len)]) # Ending cap faces.append([point_map[(rows-1,row_len-1-x)] for x in range(row_len)]) else: # Connect the end to the start for col_ix in range(row_len): faces.append([ point_map[(0, (col_ix-1+torus_connect_offset)%row_len)], point_map[(0, (col_ix+torus_connect_offset)%row_len)], point_map[(rows-1, col_ix%row_len)], point_map[(rows-1, (col_ix-1)%row_len)] ]) return cls(points=point_list, faces=faces, convexity=convexity) @classmethod def from_heightmap(cls, heights: List[List[float]], base: float = 0., step_x: float = 1., step_y: float = 1., convexity: int = 10): """Construct a polyhedron from a 2D matrix of heights. If the height at [0,0] is Z, it maps to the point (0, 0, Z). Arguments: - heights: The 2D matrix of heights - base: The height at which the base will be - in the scale of heights (optional; default 0) - step_x: The X coordinate becomes `step_x * index_x` (default 1) - step_y: The Y coordinate becomes `step_y * index_y` (default 1) - convexity: see OpenSCAD """ rows = len(heights) row_len = len(heights[0]) point_list = [] point_map = {} # { (row_ix,col_ix) -> list_ix, ... bottom_point_map = {} for row_ix, row in enumerate(heights): for col_ix, height in enumerate(row): point = Point([row_ix*step_x, col_ix*step_y, height]) bottom_point = Point([row_ix*step_x, col_ix*step_y, base]) point_map[(row_ix, col_ix)] = len(point_list) point_list.append(point) bottom_point_map[(row_ix, col_ix)] = len(point_list) point_list.append(bottom_point) faces = [] # Surface (top) faces # r 10 11 # c # 10 1 2 # 11 4 3 for row_ix in range(1, rows): for col_ix in range(1, row_len): faces.append([ point_map[(row_ix-1, col_ix-1)], point_map[(row_ix, col_ix-1)], point_map[(row_ix, col_ix)], point_map[(row_ix-1, col_ix)] ]) # Bottom faces for row_ix in range(1, rows): for col_ix in range(1, row_len): faces.append([ bottom_point_map[(row_ix-1, col_ix-1)], # 1 bottom_point_map[(row_ix-1, col_ix)], # 4 bottom_point_map[(row_ix, col_ix)], # 3 bottom_point_map[(row_ix, col_ix-1)] # 2 ]) # Side faces for row_ix in range(1, rows): m = row_len - 1 faces.append([ point_map[(row_ix-1, m)], point_map[(row_ix, m)], bottom_point_map[(row_ix, m)], bottom_point_map[(row_ix-1, m)] ]) faces.append([ point_map[(row_ix, 0)], point_map[(row_ix-1, 0)], bottom_point_map[(row_ix-1, 0)], bottom_point_map[(row_ix, 0)] ]) for col_ix in range(1, row_len): m = rows - 1 faces.append([ point_map[(m, col_ix-1)], point_map[(m, col_ix)], bottom_point_map[(m, col_ix)], bottom_point_map[(m, col_ix-1)] ]) faces.append([ point_map[(0, col_ix)], point_map[(0, col_ix-1)], bottom_point_map[(0, col_ix-1)], bottom_point_map[(0, col_ix)] ]) return cls(points=point_list, faces=faces, convexity=convexity) def render(self) -> str: """Render the object into OpenSCAD code""" faces_list = [f"[{','.join([str(x) for x in face])}]" for face in self.faces] return f"polyhedron(points=[{','.join([p.render() for p in self.points])}], faces=[{','.join(faces_list)}], convexity={self.convexity});" def render_stl(self) -> str: """Export the polyhedron as an STL file""" stl = [] def write_triangle(p1, p2, p3): normal = (p2 - p1).cross(p3 - p1) if normal.is_zero(): # Degenerate triangle return normal = normal.norm() stl.append("facet normal " + normal.render_stl()) stl.append("outer loop") for p in [p1, p2, p3]: stl.append("vertex " + p.render_stl()) stl.append("endloop") stl.append("endfacet") stl.append("solid oscpy") for face in self.faces: face = [self.points[i] for i in face] # stl.append(f"# FACE {len(face)} {','.join([p.render() for p in face])}") if len(face) < 3: raise Exception("Face has less than 3 points") elif len(face) == 3: write_triangle(face[0], face[1], face[2]) elif len(face) == 4: # Decide which diagonal is best to break on d1 = face[0].sub(face[2]).length() d2 = face[1].sub(face[3]).length() if d1 < d2: write_triangle(face[0], face[1], face[2]) write_triangle(face[0], face[2], face[3]) else: write_triangle(face[0], face[1], face[3]) write_triangle(face[1], face[2], face[3]) else: # Add central point and split face in a star-shaped form # of course this won't always work on concave faces s = None for p in face: if s is None: s = p else: s += p s = s.scale(1 / len(face)) for i in range(len(face)): i_next = i + 1 if i_next > len(face) - 1: i_next = 0 write_triangle(face[i], face[i_next], s) stl.append("endsolid oscpy") return "\n".join(stl)Ancestors
Static methods
def from_heightmap(heights: List[List[float]],
base: float = 0.0,
step_x: float = 1.0,
step_y: float = 1.0,
convexity: int = 10)-
Construct a polyhedron from a 2D matrix of heights. If the height at [0,0] is Z, it maps to the point (0, 0, Z).
Arguments
- heights: The 2D matrix of heights
- base: The height at which the base will be - in the scale of heights (optional; default 0)
- step_x: The X coordinate becomes
step_x * index_x(default 1) - step_y: The Y coordinate becomes
step_y * index_y(default 1) - convexity: see OpenSCAD
def torus(points: List[List[list | Point]],
torus_connect_offset: int = 0,
convexity: int = 10)-
Construct a torus-like polyhedron from a 2D array of points. Each row of points must be oriented clockwise when looking from the first row (loop) toward the next. The rows of points form loops.
Arguments
- points: A 2D array of points
- torus_connect_offset: int, Whether to shift which points are connected in a torus in the last segment
- convexity: int, see OpensCAD
def tube(points: List[List[list | Point]],
make_torus: bool = False,
torus_connect_offset: int = 0,
convexity: int = 10)-
Construct a tube-like polyhedron from a 2D array of points. Each row of points must be oriented clockwise when looking at the pipe at the start inwards. The rows of points form loops.
Arguments
- points: A 2D array of points
- make_torus: bool, Whether to create a torus-like shape instead of a pipe with ends
- torus_connect_offset: int, Whether to shift which points are connected in a torus in the last segment
- convexity: int, see OpensCAD
Methods
def color(self, r, g, b, a=1.0) ‑> Object-
Apply a color and return a new object. See https://en.wikibooks.org/wiki/OpenSCAD_User_Manual/Transformations#color
def delta_offset(self, delta, chamfer=False)-
Inherited from:
Object.delta_offsetReturn a new 2D interior or exterior outline from an existing outline. See https://en.wikibooks.org/wiki/OpenSCAD_User_Manual/Transformations#offset
def diff(self,
tool: list | ForwardRef('Object')) ‑> Object-
Remove from the object using a difference operator, and return a new object. See …
def extrude(self, height, convexity=10, center: bool = False) ‑> Object-
Inherited from:
Object.extrudeApply a linear extrusion and return a new object. If
centeris false, the linear extrusion Z range is from 0 to height; if it is true, the range is … def intersection(self,
objects: list | ForwardRef('Object')) ‑> Object-
Inherited from:
Object.intersectionGet the intersection of self and an object of list of objects, and return a new object. See …
def move(self,
v: list | Point) ‑> Object-
Apply a translation and return a new object. Synonym of
translate() def radial_offset(self, r)-
Inherited from:
Object.radial_offsetReturn a new 2D interior or exterior outline from an existing outline. See https://en.wikibooks.org/wiki/OpenSCAD_User_Manual/Transformations#offset
def render(self) ‑> str-
Render the object into OpenSCAD code
def render_stl(self) ‑> str-
Export the polyhedron as an STL file
def rotate(self,
a,
v: list | Point) ‑> Object-
Apply a rotation and return a new object. See https://en.wikibooks.org/wiki/OpenSCAD_User_Manual/Transformations#rotate
def rotate_extrude(self, angle, convexity=10) ‑> Object-
Inherited from:
Object.rotate_extrudeApply a rotational extrusion and return a new object. For all points x >= 0 must be true. See …
def scale(self,
v: list | Point | float) ‑> Object-
Apply scaling and return a new object. Accepts a vector (a Point object or a list of floats) or a single float for uniform scaling. See …
def translate(self,
v: list | Point) ‑> Object-
Inherited from:
Object.translateApply a translation and return a new object. See https://en.wikibooks.org/wiki/OpenSCAD_User_Manual/Transformations#translate
def union(self,
objects: list | ForwardRef('Object')) ‑> Object-
Form the union of self and an object or list of objects, and return a new object. See …