npxpy.resources.Mesh

Bases: Resource

A class to represent a mesh resource with attributes such as translation, rotation, scale, etc.

Attributes:

Name	Type	Description
translation	List[float]	Translation values [x, y, z].
rotation	List[float]	Rotation values [psi, theta, phi].
scale	List[float]	Scale values [x, y, z].
enhance_mesh	bool	Whether to enhance the mesh.
simplify_mesh	bool	Whether to simplify the mesh.
target_ratio	float	Target ratio for mesh simplification.

Source code in npxpy/resources.py

class Mesh(Resource):
    """
    A class to represent a mesh resource with attributes such as translation, rotation, scale, etc.

    Attributes:
        translation (List[float]): Translation values [x, y, z].
        rotation (List[float]): Rotation values [psi, theta, phi].
        scale (List[float]): Scale values [x, y, z].
        enhance_mesh (bool): Whether to enhance the mesh.
        simplify_mesh (bool): Whether to simplify the mesh.
        target_ratio (float): Target ratio for mesh simplification.
    """

    def __init__(
        self,
        file_path: str,
        name: str = "mesh",
        translation: List[float] = [0, 0, 0],
        auto_center: bool = False,
        rotation: List[float] = [0.0, 0.0, 0.0],
        scale: List[float] = [1.0, 1.0, 1.0],
        enhance_mesh: bool = True,
        simplify_mesh: bool = False,
        target_ratio: float = 100.0,
    ):
        """
        Initialize the mesh resource with the specified parameters.

        Parameters:
            file_path (str): Path where the mesh is stored (original file location).
            name (str, optional): Name of the mesh resource. Defaults to 'mesh'.
            translation (List[float], optional): Translation values [x, y, z]. Defaults to [0, 0, 0].
            auto_center (bool, optional): Whether to auto-center the mesh. Defaults to False.
            rotation (List[float], optional): Rotation values [psi, theta, phi]. Defaults to [0.0, 0.0, 0.0].
            scale (List[float], optional): Scale values [x, y, z]. Defaults to [1.0, 1.0, 1.0].
            enhance_mesh (bool, optional): Whether to enhance the mesh. Defaults to True.
            simplify_mesh (bool, optional): Whether to simplify the mesh. Defaults to False.
            target_ratio (float, optional): Target ratio for mesh simplification. Defaults to 100.0.
        """
        super().__init__(
            resource_type="mesh_file", name=name, file_path=file_path
        )

        # Set attributes with validation
        self.translation = translation
        self.auto_center = auto_center
        self.rotation = rotation
        self.scale = scale
        self.enhance_mesh = enhance_mesh
        self.simplify_mesh = simplify_mesh
        self.target_ratio = target_ratio
        self.original_triangle_count = self._get_triangle_count(file_path)

        # Load the mesh data
        self.mesh_data = stl_mesh.Mesh.from_file(file_path)

        # Apply auto-centering if enabled
        if self.auto_center:
            self._auto_center()

    @property
    def translation(self):
        return self._translation

    @translation.setter
    def translation(self, value: List[Any]):
        if len(value) != 3:
            raise ValueError(
                "Translation must have exactly 3 elements [x, y, z]"
            )
        try:
            self._translation = [float(v) for v in value]
        except ValueError:
            raise ValueError("Translation elements must be numeric values.")

    @property
    def rotation(self):
        return self._rotation

    @rotation.setter
    def rotation(self, value: List[Any]):
        if len(value) != 3:
            raise ValueError(
                "Rotation must have exactly 3 elements [psi, theta, phi]"
            )
        try:
            self._rotation = [float(v) for v in value]
        except ValueError:
            raise ValueError("Rotation elements must be numeric values.")

    @property
    def scale(self):
        return self._scale

    @scale.setter
    def scale(self, value: List[Any]):
        if len(value) != 3:
            raise ValueError("Scale must have exactly 3 elements [x, y, z]")
        try:
            self._scale = [float(v) for v in value]
        except ValueError:
            raise ValueError("Scale elements must be numeric values.")

    @property
    def target_ratio(self):
        return self._target_ratio

    @target_ratio.setter
    def target_ratio(self, value: Any):
        try:
            value = float(value)
        except ValueError:
            raise ValueError("Target ratio must be a numeric value.")
        if not (0 <= value <= 100):
            raise ValueError("Target ratio must be between 0 and 100")
        self._target_ratio = value

    def _auto_center(self):
        """
        Auto-center the mesh by translating it so the bounding box center aligns with the origin
        in the x and y axes, and the lowest z coordinate is set to 0.
        """
        all_vertices = self.mesh_data.vectors.reshape(-1, 3)

        # Calculate the min and max coordinates for bounding box
        min_coords = all_vertices.min(axis=0)
        max_coords = all_vertices.max(axis=0)

        # Center x and y by calculating the bounding box center
        bounding_box_center = (min_coords + max_coords) / 2.0
        bounding_box_center[2] = min_coords[2]  # For z, use the lowest point

        # Calculate the translation
        translation = -bounding_box_center
        translation[2] = -min_coords[
            2
        ]  # Translate only enough to set the lowest z to 0

        # Apply the translation to the mesh
        self.mesh_data.translate(translation)

        # Update translation property to reflect the applied translation
        self.translation = [
            t + c for t, c in zip(self.translation, translation)
        ]

    def _get_triangle_count(self, path: str) -> int:
        """
        Get the number of triangles in the mesh.

        Parameters:
            path (str): Path to the mesh file.

        Returns:
            int: Number of triangles in the mesh.

        Raises:
            FileNotFoundError: If the mesh file does not exist.
            Exception: If there is an error reading the STL file.
        """
        if not os.path.isfile(path):
            raise FileNotFoundError(f"Mesh file not found: {path}")

        try:
            mesh_data = stl_mesh.Mesh.from_file(path)
            return len(mesh_data.vectors)
        except Exception as e:
            raise Exception(f"Error reading STL file: {e}")

    def to_dict(self) -> Dict[str, Any]:
        """
        Converts the current state of the object into a dictionary representation.

        Returns:
            dict: Dictionary representation of the current state of the object.
        """
        resource_dict = super().to_dict()
        resource_dict.update(
            {
                "translation": self.translation,
                "auto_center": self.auto_center,
                "rotation": self.rotation,
                "scale": self.scale,
                "enhance_mesh": self.enhance_mesh,
                "simplify_mesh": self.simplify_mesh,
                "target_ratio": self.target_ratio,
                "properties": {
                    "original_triangle_count": self.original_triangle_count
                },
            }
        )
        return resource_dict

__init__(file_path, name='mesh', translation=[0, 0, 0], auto_center=False, rotation=[0.0, 0.0, 0.0], scale=[1.0, 1.0, 1.0], enhance_mesh=True, simplify_mesh=False, target_ratio=100.0)

Initialize the mesh resource with the specified parameters.

Parameters:

Name	Type	Description	Default
file_path	str	Path where the mesh is stored (original file location).	required
name	str	Name of the mesh resource. Defaults to 'mesh'.	'mesh'
translation	List[float]	Translation values [x, y, z]. Defaults to [0, 0, 0].	[0, 0, 0]
auto_center	bool	Whether to auto-center the mesh. Defaults to False.	False
rotation	List[float]	Rotation values [psi, theta, phi]. Defaults to [0.0, 0.0, 0.0].	[0.0, 0.0, 0.0]
scale	List[float]	Scale values [x, y, z]. Defaults to [1.0, 1.0, 1.0].	[1.0, 1.0, 1.0]
enhance_mesh	bool	Whether to enhance the mesh. Defaults to True.	True
simplify_mesh	bool	Whether to simplify the mesh. Defaults to False.	False
target_ratio	float	Target ratio for mesh simplification. Defaults to 100.0.	100.0

Source code in npxpy/resources.py

def __init__(
    self,
    file_path: str,
    name: str = "mesh",
    translation: List[float] = [0, 0, 0],
    auto_center: bool = False,
    rotation: List[float] = [0.0, 0.0, 0.0],
    scale: List[float] = [1.0, 1.0, 1.0],
    enhance_mesh: bool = True,
    simplify_mesh: bool = False,
    target_ratio: float = 100.0,
):
    """
    Initialize the mesh resource with the specified parameters.

    Parameters:
        file_path (str): Path where the mesh is stored (original file location).
        name (str, optional): Name of the mesh resource. Defaults to 'mesh'.
        translation (List[float], optional): Translation values [x, y, z]. Defaults to [0, 0, 0].
        auto_center (bool, optional): Whether to auto-center the mesh. Defaults to False.
        rotation (List[float], optional): Rotation values [psi, theta, phi]. Defaults to [0.0, 0.0, 0.0].
        scale (List[float], optional): Scale values [x, y, z]. Defaults to [1.0, 1.0, 1.0].
        enhance_mesh (bool, optional): Whether to enhance the mesh. Defaults to True.
        simplify_mesh (bool, optional): Whether to simplify the mesh. Defaults to False.
        target_ratio (float, optional): Target ratio for mesh simplification. Defaults to 100.0.
    """
    super().__init__(
        resource_type="mesh_file", name=name, file_path=file_path
    )

    # Set attributes with validation
    self.translation = translation
    self.auto_center = auto_center
    self.rotation = rotation
    self.scale = scale
    self.enhance_mesh = enhance_mesh
    self.simplify_mesh = simplify_mesh
    self.target_ratio = target_ratio
    self.original_triangle_count = self._get_triangle_count(file_path)

    # Load the mesh data
    self.mesh_data = stl_mesh.Mesh.from_file(file_path)

    # Apply auto-centering if enabled
    if self.auto_center:
        self._auto_center()

to_dict()

Converts the current state of the object into a dictionary representation.

Returns:

Name	Type	Description
dict	Dict[str, Any]	Dictionary representation of the current state of the object.

Source code in npxpy/resources.py

def to_dict(self) -> Dict[str, Any]:
    """
    Converts the current state of the object into a dictionary representation.

    Returns:
        dict: Dictionary representation of the current state of the object.
    """
    resource_dict = super().to_dict()
    resource_dict.update(
        {
            "translation": self.translation,
            "auto_center": self.auto_center,
            "rotation": self.rotation,
            "scale": self.scale,
            "enhance_mesh": self.enhance_mesh,
            "simplify_mesh": self.simplify_mesh,
            "target_ratio": self.target_ratio,
            "properties": {
                "original_triangle_count": self.original_triangle_count
            },
        }
    )
    return resource_dict