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chemdiagrams.managers.figure_manager

FigureManager

Creates and owns the Matplotlib figure and axes used by the diagram.

Acts as the central reference point for all other managers, which access the figure and axes through this object rather than holding their own references.

Source code in src/chemdiagrams/managers/figure_manager.py 
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class FigureManager:
    """
    Creates and owns the Matplotlib figure and axes used by the diagram.

    Acts as the central reference point for all other managers, which
    access the figure and axes through this object rather than holding
    their own references.
    """

    def __init__(self, fontsize: int, dpi: int = 150, ax: Axes | None = None) -> None:
        """
        Initialize the Matplotlib figure and configure default tick styling.

        Parameters
        ----------
        fontsize : int, optional
            Base font size applied to axis tick labels throughout the diagram.
            Default is ``constants.STD_FONTSIZE``.
        dpi : int, optional
            Resolution of the figure in dots per inch. Default is 150.
        ax : matplotlib.axes.Axes or None, optional
            External Matplotlib axes to use for the diagram. If None, a new figure
            and axes are created internally. If provided, the figure from this axes
            is used. Default is None.
        """

        # Sanity checks
        Validators.validate_number(fontsize, "fontsize", min_value=0)
        Validators.validate_number(dpi, "dpi", min_value=0)

        # Create ax and fig or use external ax if provided
        if ax is not None:
            if not isinstance(ax, Axes):
                raise TypeError("ax must be a matplotlib.axes.Axes object.")
            self.ax = ax
            fig = ax.get_figure()
            if not isinstance(fig, plt.Figure):
                raise TypeError(
                    "The provided ax does not belong to a valid Matplotlib figure."
                )
            self.fig = fig
            self.has_external_ax = True
        else:
            self.fig = plt.figure(dpi=dpi)
            self.ax = self.fig.gca()
            self.has_external_ax = False

        # Configure axis
        self.ax.tick_params(
            which="both", direction="inout", top=False, right=False, bottom=False
        )
        self.ax.tick_params(which="both", labelsize=fontsize)
        self.ax.set_xticks([])
        self.ax.set_axisbelow(True)
        self.fontsize = fontsize

__init__(fontsize, dpi=150, ax=None)

Initialize the Matplotlib figure and configure default tick styling.

Parameters:

Name Type Description Default
fontsize int

Base font size applied to axis tick labels throughout the diagram. Default is constants.STD_FONTSIZE.

 required
dpi int

Resolution of the figure in dots per inch. Default is 150.

 150
ax Axes or None

External Matplotlib axes to use for the diagram. If None, a new figure and axes are created internally. If provided, the figure from this axes is used. Default is None.

 None
Source code in src/chemdiagrams/managers/figure_manager.py 
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def __init__(self, fontsize: int, dpi: int = 150, ax: Axes | None = None) -> None:
    """
    Initialize the Matplotlib figure and configure default tick styling.

    Parameters
    ----------
    fontsize : int, optional
        Base font size applied to axis tick labels throughout the diagram.
        Default is ``constants.STD_FONTSIZE``.
    dpi : int, optional
        Resolution of the figure in dots per inch. Default is 150.
    ax : matplotlib.axes.Axes or None, optional
        External Matplotlib axes to use for the diagram. If None, a new figure
        and axes are created internally. If provided, the figure from this axes
        is used. Default is None.
    """

    # Sanity checks
    Validators.validate_number(fontsize, "fontsize", min_value=0)
    Validators.validate_number(dpi, "dpi", min_value=0)

    # Create ax and fig or use external ax if provided
    if ax is not None:
        if not isinstance(ax, Axes):
            raise TypeError("ax must be a matplotlib.axes.Axes object.")
        self.ax = ax
        fig = ax.get_figure()
        if not isinstance(fig, plt.Figure):
            raise TypeError(
                "The provided ax does not belong to a valid Matplotlib figure."
            )
        self.fig = fig
        self.has_external_ax = True
    else:
        self.fig = plt.figure(dpi=dpi)
        self.ax = self.fig.gca()
        self.has_external_ax = False

    # Configure axis
    self.ax.tick_params(
        which="both", direction="inout", top=False, right=False, bottom=False
    )
    self.ax.tick_params(which="both", labelsize=fontsize)
    self.ax.set_xticks([])
    self.ax.set_axisbelow(True)
    self.fontsize = fontsize