Markers

markers.py

Marker registry for Plot1D and Plot2D panels inside a Figure.

The public API mirrors matplotlib’s collection kwargs:

plot.add_circles(offsets, name=”group1”,

facecolors=”#ff0000”, edgecolors=”#ffffff”, radius=5, labels=[…])

plot.markers[“circles”][“group1”].set(offsets=new_offsets, radius=3)

Design

• MarkerGroup – a single named collection of markers (one type).

• MarkerTypeDict – dict-like for one type; mutations propagate to the plot.

• MarkerRegistry – top-level two-level dict: registry[type][name].

All state is stored as plain Python dicts; no traitlets here. The _push callback is supplied by the parent plot and is responsible for serialising the full registry into the panel’s JSON trait on the Figure widget.

Wire-format translation

The JS renderer uses the same internal field names as the standalone viewers (color, fill_color, fill_alpha, sizes, etc.). MarkerGroup stores matplotlib-style names and to_wire() translates before JSON serialisation.

Classes

MarkerGroup	A named collection of markers of one type on one plot.
MarkerTypeDict	Dict-like container for all named groups of one marker type.
MarkerRegistry	Top-level two-level marker registry for a plot.

Full Reference

class anyplotlib.markers.MarkerGroup(marker_type, name, kwargs, push_fn)

Bases: object

A named collection of markers of one type on one plot.

Parameters:

• marker_type (str) – One of the supported marker types ('circles', 'lines', …).

• name (str) – User-facing name (key in the parent MarkerTypeDict).

• kwargs (dict) – Initial matplotlib-style kwargs for this group.

• push_fn (callable) – Zero-arg callback that serialises the full registry and pushes it to the parent figure trait.

set(**kwargs)

Update one or more properties and push the change to the plot.

Parameters:

**kwargs (dict) – Properties to update (e.g., offsets, radius, facecolors). Matplotlib-style names are translated to wire format.

Return type:

None

to_wire(group_id)

Return a dict in the JS wire format for this marker group.

Parameters:

group_id (str) – Unique identifier for this marker group (usually UUID).

Returns:

Wire-format dict with type-specific structure, ready for JSON serialization and transmission to the JavaScript renderer.

Return type:

dict

class anyplotlib.markers.MarkerTypeDict(marker_type, push_fn)

Bases: object

Dict-like container for all named groups of one marker type.

Any modification (__setitem__, __delitem__) automatically triggers the _push_fn callback so the plot re-renders.

Parameters:

• marker_type (str) – Type of markers (e.g., ‘circles’, ‘arrows’, ‘lines’).

• push_fn (callable) – Zero-arg callback to trigger re-render on mutations.

keys()

Return group names.

values()

Return MarkerGroup objects.

items()

Return (name, MarkerGroup) pairs.

pop(name, *args)

Remove and return a MarkerGroup by name.

Parameters:

• name (str) – Name of the group to remove.

• *args (optional) – Default value if name is not found.

Returns:

The removed group, or default value if provided.

Return type:

MarkerGroup

Raises:

KeyError – If name is not found and no default is provided.

to_wire_list()

Serialise all groups to a list of wire-format dicts.

Return type:

list

class anyplotlib.markers.MarkerRegistry(push_fn, allowed=None)

Bases: object

Top-level two-level marker registry for a plot.

Usage:

plot.markers["circles"]["group1"].set(offsets=new_offsets)

plot.markers is a MarkerRegistry. Indexing by type returns a MarkerTypeDict (auto-created on first access).

Parameters:

allowed (frozenset | None)

add(marker_type, name=None, **kwargs)

Add a marker group, returning the MarkerGroup.

Parameters:

• marker_type (str) – Type string, e.g. 'circles', 'lines', 'arrows'.

• name (str, optional) – Group name. Auto-generated ('circles_1' etc.) if None.

• **kwargs (dict) – Matplotlib-style kwargs for the group (offsets, radius, colors, etc.).

Returns:

The created marker group. Call .set() to update, or access properties as attributes.

Return type:

MarkerGroup

Examples

>>> group = registry.add("circles", name="my_circles", offsets=[[10, 20]], radius=5)
>>> group.set(radius=8)

remove(marker_type, name)

Remove a named marker group and trigger re-render.

Parameters:

• marker_type (str) – Type of the group.

• name (str) – Name of the group to remove.

Raises:

KeyError – If the type or name is not found.

Return type:

None

clear()

Remove all markers of all types and trigger re-render.

Return type:

None

to_wire_list()

Flatten the full registry to a list of wire-format dicts.

Returns:

Wire-format dicts ready for JSON serialization and JS rendering.

Return type:

list of dict