libpetri-export — DOT/Graphviz Export Pipeline

Converts a PetriNet into a DOT string for Graphviz rendering.

Architecture

The pipeline has four layers, separating concerns cleanly:

PetriNet ──► map_to_graph() ──► Graph ──► render_dot() ──► DOT string
             (knows Petri nets)           (format-agnostic)

1. Styles ([styles]) — Color/shape constants from the shared spec
2. Graph model ([graph]) — Format-agnostic typed graph (nodes, edges, clusters)
3. Mapper ([mapper]) — Petri net → Graph (place classification, arc styling)
4. Renderer ([dot_renderer]) — Graph → DOT string (no Petri net knowledge)

Quick Start

use libpetri_core::place::Place;
use libpetri_core::transition::Transition;
use libpetri_core::petri_net::PetriNet;
use libpetri_core::input::one;
use libpetri_core::output::out_place;
use libpetri_core::action::fork;
use libpetri_export::dot_exporter::dot_export;

let p1 = Place::<i32>::new("input");
let p2 = Place::<i32>::new("output");

let t = Transition::builder("process")
    .input(one(&p1))
    .output(out_place(&p2))
    .action(fork())
    .build();

let net = PetriNet::builder("example").transition(t).build();
let dot = dot_export(&net, None);

assert!(dot.contains("digraph"));

Example Output

Configuration

DotConfig controls rendering:

Visual Vocabulary

• Green circles — start places (no incoming arcs)
• Blue circles — end places (no outgoing arcs)
• Red dashed circles — environment places (external event injection)
• Solid arrows — input/output arcs
• Dashed arrows — read arcs
• Dot-headed arrows — inhibitor arcs
• Double arrows — reset arcs