UML Diagram Generator

Purpose & User Intent: This tool solves the problem of producing clear UML diagrams from a simple declarative model of elements and relationships. It is used by software developers, architects, educators, and teams who need quick, shareable diagrams without desktop diagramming software. Use during design discussions, architecture reviews, or learning sessions to communicate structure, dependencies, and scope. The output supports collaboration by exporting diagrams that can be embedded in docs or shared in code reviews.
Core Logic & Features: The tool supports domain concepts such as elements (nodes representing classes or modules) and relationships (edges such as association, inheritance, aggregation). Required features include: define at least one element and one relationship; render a class-like diagram with directional relationships; produce a scalable vector graphic. Optional features include: package/group organization, multiple diagram templates for common architectures (MVC, layered, microservice), automatic layout with stable coordinates, and output formats beyond SVG (PNG, JSON model export).
Inputs & Outputs: Inputs include elements (name, optional attributes, optional operations), relationships (type, from, to, optional multiplicities), and optional groupings or packages. Validation ensures referenced elements exist and names are non-empty. Outputs include an SVG diagram with scalable rendering, a plain-text export option for the underlying model, and a machine-readable JSON model if supported in future versions; coordinate system and styling rules ensure consistent exports.
Algorithms & Calculations: The tool builds a graph model with nodes as elements and edges as relationships. A layout pass positions nodes to minimize edge crossings while respecting packages and groupings. Edge rendering adapts to relationship type; dimensions are computed to support large diagrams with deterministic coordinates for repeatable exports.
Error & Edge Cases: Missing inputs results in an empty diagram placeholder; unknown element references produce validation errors; cyclic inheritance is rendered with loop indicators for clarity; extremely large models may trigger automatic downscaling or pagination in generated outputs.
Industry/Region & Localization: UML semantics align with standard modeling practices; outputs use pixels for layout and UTF-8 for names; no locale-specific data is required.
Assumptions & Exclusions: Assumes users provide a valid model either declaratively or programmatically; not responsible for semantic correctness of the domain model; excludes live editing or runtime diagram generation; collaboration features are optional.