Semantic Markdown Preview

A Visual Studio Code extension that brings your RDF, Turtle, and N3 files to life. Semantic Markdown Preview adds syntax highlighting and interactive graph visualizations directly within your Markdown preview.

Features

1. Enhanced Syntax Highlighting

Get rich, semantic syntax highlighting for turtle and n3 code blocks. Distinct colors for users, prefixes, IRIs, literals, and keywords make your data easier to read.

```turtle
@prefix ex: <http://example.org/> .
ex:John a ex:Person ;
    ex:name "John Doe" .
```

2. Interactive Graph Visualization

Visualize your RDF data as a force-directed graph. You have two options:

• preview: Renders the code block AND the graph visualization.
• graph: Renders ONLY the graph visualization (hides the code).

```turtle graph
@prefix ex: <http://example.org/> .
ex:John a ex:Person ;
    ex:knows ex:Jane .
```

The extension automatically:

• Classifies Nodes:
  • Classes (Internal): Light Blue Ellipses.
  • External Classes: Dark Blue Ellipses.
  • Instances: Pink Ellipses.
  • Literals: Yellow Rectangles.
  • Datatypes: Grey Rectangles.
• Styles Edges:
  • Hierarchy (subClassOf): Thick Grey lines with hollow arrows.
  • Membership (a/rdf:type): Purple lines.
  • Semantic: Bright Blue lines.
  • Data: Orange lines.
• Optimizes Layout: Uses physics simulation to cluster related instances and separate hierarchies.

3. Customizable Filtering

Control what appears in your graph using simple flags in the code block header.

Available Options:

• no-literals: Hide literal values (strings, numbers).
• no-external: Hide classes from external namespaces (like foaf, schema).
• no-classes: Hide all Class nodes.
• no-instances: Hide all Instance nodes.

Examples:

Hide literals to focus on relationships:

```turtle preview no-literals
@prefix ex: <http://example.org/> .
ex:John a ex:Person ;
    ex:knows ex:Jane ;
    ex:age 30 ;          # Hidden
    ex:name "John" .     # Hidden
```

Show only the ontology structure (no instances or literals):

```turtle preview no-instances no-literals
@prefix ex: <http://example.org/> .
@prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#> .

ex:Person a rdfs:Class .
ex:Employee rdfs:subClassOf ex:Person .
# Instances like ex:John a ex:Employee will be hidden
```

4. Theme Support

Fully compatible with both Dark and Light themes. The visualization colors adapt to ensure readability in any environment.

Usage

1. Open a Markdown file.
2. Create a code block with turtle, n3, or rdf.
3. Add preview to the header to enable visualization.
4. (Optional) Add filters like no-literals to customize the view.
5. Open the Markdown: Open Preview command.

Requirements

• Visual Studio Code 1.96.0 or higher.
• No external dependencies required (extension bundles everything).

Extension Settings

Currently, this extension uses inline configuration via Markdown code block attributes. Global settings may be added in future versions.

Known Issues

• Complex owl:unionOf constructs are currently visualized as raw lists.
• Graph layout may shift slightly on re-render due to the physics engine.

Release Notes

0.0.1

• Initial release.
• Support for Turtle/N3 syntax highlighting.
• Interactive Graph Visualization with Cytoscape.js.
• Filtering options (no-literals, no-external, etc.).