TheJIT Visual Lab

TheJIT Visual Lab is a small collection of browser-based data-visualization tools maintained for thejit.org:

• Sankey Diagram Generator
• Radar Chart Maker
• Bubble Chart Maker

This is a new project maintained by TheJIT’s current publisher. It is not the original JavaScript InfoVis Toolkit, and it is not maintained by that project’s original author, Nicolás García Belmonte.

Why these tools

The project is built around three product decisions:

1. Start with a spreadsheet table instead of a tool-specific mini-language.
2. Keep pasted data in the browser instead of sending it to an upload endpoint.
3. Explain the visual encoding and its limits instead of treating every chart type as interchangeable decoration.

All three tools work without an account, analytics dependency, watermark, or third-party chart library. They export editable SVG and 2× PNG. Each rendered chart also includes a preflight report, a specific text description, and a keyboard-readable data table so exact values do not depend on pointer hover. Each tool page has its own four-step workflow, reading guidance, and an input-adjacent explanation of what stays local.

Product behavior

Sankey Diagram Generator

Paste Source, Target, Value rows copied from Excel, Google Sheets, or a text file. Duplicate source/target pairs are aggregated and counted; users can preserve input order, sort alphabetically, or balance a column by flow size. Long labels are audited and can wrap, visually shorten, or be hidden. Transit nodes with unequal incoming and outgoing totals are reported with both values and the difference. Cyclic flows are rejected with a visible explanation.

Radar Chart Maker

Use the first column for 3–12 metric labels and the following columns for up to five series. Values must be non-negative and cannot exceed the declared shared maximum. Longer axis labels wrap without a visual ellipsis, exact values remain available in a companion table, and legend items can hide or restore a series. The same values can be inspected as grouped bars. A scale audit reports maximum, headroom, zero values, and density; an accessible ZIP combines SVG, 2× PNG, exact CSV, and a chart description.

Bubble Chart Maker

Paste Label, X, Y, Size, Group rows. X and Y axis names come from the header, while circle area is proportional to Size. A size legend makes that encoding explicit; Group is optional. Manual X/Y limits support comparable charts, the renderer keeps edge bubbles inside the plot, and duplicate coordinates are disclosed rather than silently presented as separate visible points. Invalid rows either stop the render or can be skipped with a list. Hidden labels are counted, while very small bubbles receive a dashed locator ring that does not change their data-encoded area.

Privacy model

Parsing, validation, chart layout, and export happen in the current browser tab. The plugin has:

• no dataset upload endpoint;
• no account or persistence layer;
• no third-party JavaScript request;
• no telemetry call in the visualization code.

Closing or clearing the tab removes the pasted data.

WordPress installation

1. Zip the thejit-visual-lab directory.
2. In WordPress, open Plugins → Add New → Upload Plugin.
3. Install and activate TheJIT Visual Lab.
4. Create the pages below and place the matching shortcode in each.

URL	Shortcode
/tools/	[thejit_visual_lab]
/tools/sankey-diagram-generator/	[thejit_sankey]
/tools/radar-chart-maker/	[thejit_radar]
/tools/bubble-chart-maker/	[thejit_bubble]

The plugin’s page template calls the active theme’s get_header() and get_footer(). The real logo, global navigation, categories, post feed, and footer remain theme-owned.

The plugin also contains an optional homepage introduction, tool shelf, and editorial bridge. THEJIT_VISUAL_LAB_ENABLE_HOME_SECTIONS remains enabled in v0.4.0 after the site owner explicitly approved the reviewed homepage proposal. The original article container remains immediately after the new sections.

Development

The renderers are dependency-free ES modules in assets/:

• lab-core.js — parsing, SVG helpers, palettes, and export
• sankey.js — acyclic flow layout
• radar.js — shared-scale radial comparison
• bubble.js — X/Y plot with area-proportional Size
• app.js — workbench interaction

Run JavaScript syntax checks with:

node --check assets/app.js
node --check assets/lab-core.js
node --check assets/sankey.js
node --check assets/radar.js
node --check assets/bubble.js
node tests/parser-tests.mjs

Deliberate limits

• Sankey: no cycles, manual node positioning, or large-file streaming.
• Radar: no negative values, mixed units, or more than five series.
• Bubble: maximum 80 rows; duplicate coordinates are reported but not moved; no collision-avoidance simulation or live dashboard.
• All tools: no cloud save, collaboration, or share-link feature.

These limits are stated on the public product pages so users can choose another chart form or a heavier tool when appropriate.

License

The new Visual Lab code is available under the MIT License. No original JIT source code is included.