[map-projections] Map with Different Projections

[MarkusNeusinger]

Description

A world map demonstrating different cartographic projections (Mercator, Robinson, Mollweide, etc.) and their distortion characteristics.

Applications

• Educational cartography
• Global data visualization
• Projection comparison
• Area-accurate world maps

Data

• World country boundaries (GeoJSON)
• country (string) - Country identifier
• value (numeric, optional) - Data to display

Notes

• Support multiple projections (Mercator, Robinson, Mollweide, Orthographic, etc.)
• Show graticule (lat/lon grid lines)
• Highlight projection distortion characteristics
• Clean coastlines and country borders
• Optional Tissot indicatrices for distortion

[claude]

✅ Spec ID: map-projections

Rationale: This spec focuses on demonstrating different cartographic projections (Mercator, Robinson, Mollweide, Orthographic, etc.) and their distortion characteristics, which is distinct from existing geographic specs that focus on displaying data (choropleth-basic, scatter-map-geographic, bubble-map-geographic).

Add label approved to begin generation.

[github-actions]

✅ Specification Ready: map-projections

PR: #3780

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specification.md

map-projections: World Map with Different Projections

Description

A world map demonstrating different cartographic projections and their distortion characteristics. This visualization showcases how the same geographic data appears under various map projections (Mercator, Robinson, Mollweide, Orthographic, etc.), revealing how each projection preserves or distorts area, shape, distance, or direction. The plot includes graticule (latitude/longitude grid lines) and optionally Tissot indicatrices to illustrate projection distortion patterns.

Applications

• Educational cartography demonstrating how map projections transform the spherical Earth to a flat surface
• Comparing projection suitability for different geographic analyses or presentations
• Visualizing global data with area-accurate projections to avoid misleading size comparisons
• Teaching geographic information systems (GIS) concepts about coordinate reference systems

Data

• World country boundaries (GeoJSON format or shapefile)
• country (string) - Country identifier or ISO code
• value (numeric, optional) - Data variable for choropleth coloring
• Size: ~200 countries (world boundaries dataset)
• Example: Natural Earth world boundaries, country-level statistics

Notes

• Support multiple projections: Mercator, Robinson, Mollweide, Orthographic, Equal Earth, Lambert Cylindrical, or other common projections
• Display graticule (latitude/longitude grid lines) at regular intervals (e.g., every 30 degrees)
• Show clean coastlines and country borders with appropriate styling
• Optional: Include Tissot indicatrices (circles that show distortion) to visualize how the projection affects area and shape
• Use a neutral color scheme for land masses when not showing data values
• Consider showing the same map in multiple projections side-by-side for comparison, or a single projection with clear title indicating which one

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Next: Add approved label to merge this specification to main.

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🤖 spec-create workflow

[github-actions]

🚀 Specification Merged!

Specification: map-projections
PR: #3780 (merged)

The specification is now in main and synced to PostgreSQL.

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Next: Add generate:{library} labels to start generating implementations.

Available libraries: matplotlib, seaborn, plotly, bokeh, altair, plotnine, pygal, highcharts, letsplot

Or use workflow dispatch for bulk operations.

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🤖 spec-create workflow