sft_wick.drawing_tikz — TikZ/PGF Diagram Backend

TikZ/PGF rendering for FeynmanDiagram objects.

This backend produces LaTeX source — a tikzpicture environment — that you can drop straight into a paper with \input{fig.tex}. It uses no external Python dependencies (pure string templates) and shares the layout, label, and style abstractions with the matplotlib backend in sft_wick.drawing.

Required LaTeX packages on the user’s side

The generated code uses standard TikZ features:

\usepackage{tikz}
\usetikzlibrary{arrows.meta}

For a self-contained PDF (standalone=True) the document also needs the standalone document class, which is part of any TeX Live / MiKTeX install.

Quick start

from sft_wick import TikzRenderer, publication_style

renderer = TikzRenderer(style=publication_style())
tikz_code = renderer.to_string(fd)
renderer.save(fd, "fig/diag1.tex")
renderer.save(
    fd, "fig/diag1_standalone.tex",
    standalone=True,         # produce a complete document
)

External-vertex labels follow the same override hierarchy as the matplotlib backend (per-call dict > callable > default formatter); see sft_wick.render_labels.

Limitations (v1)

  • rcparams is ignored — TikZ output uses LaTeX-side typography.

  • bbox on labels is ignored — TikZ labels render without a box by default; users can post-process by editing the generated every label/.style.

  • No pdflatex invocation: the user runs LaTeX themselves.

class sft_wick.drawing_tikz.TikzRenderer(style=None, external_label_fn=None, vertex_label_fn=None, label_format=None, scale=1.0, standalone=False)[source]

Bases: object

Render a FeynmanDiagram as a tikzpicture LaTeX string.

Parameters:

  • style (RenderStyle | None) – A RenderStyle. Defaults to default_style().

  • external_label_fn (LabelCallable | None) – Optional callable fn(node_id, node_attrs) -> str | None for systematic external-label overrides.

  • vertex_label_fn (LabelCallable | None) – Same shape, for interaction vertices.

  • label_format (str | None) – Default external-label format flag (overrides style.label_format when supplied).

  • scale (float) – TikZ scale=… factor — multiplies every position.

  • standalone (bool) – When True, to_string() and save() wrap the figure in a complete \documentclass{standalone} document instead of a bare tikzpicture environment.

property label_format: str
to_string(diagram, external_labels=None, vertex_labels=None, positions=None, standalone=None)[source]

Build the TikZ source for a single diagram.

Parameters:

  • diagram (FeynmanDiagram) – The diagram to render.

  • external_labels (Mapping[str, str] | None) – Optional {node_id: label} overrides.

  • vertex_labels (Mapping[str, str] | None) – Same, for interaction vertices.

  • positions (Mapping[str, tuple[float, float]] | None) – Optional {node_id: (x, y)} pin map.

  • standalone (bool | None) – If given, override the constructor’s standalone flag for this call only.

Returns:

A LaTeX source string. Always ends with a trailing newline.

Return type:

str

save(diagram, path, external_labels=None, vertex_labels=None, positions=None, standalone=None)[source]

Write the TikZ source to disk and return the path.

Creates parent directories as needed.

Parameters:
Return type:

Path

save_all(diagrams, path_pattern, external_labels=None, vertex_labels=None, positions=None, standalone=None)[source]

Save many diagrams using a str.format-style pattern.

Example: path_pattern="fig/order2_diag_{i:02d}.tex" writes fig/order2_diag_00.tex, fig/order2_diag_01.tex, …

Per-diagram overrides are keyed by subplot index.

Parameters:
Return type:

list[Path]