Projection and Geospatial Data

Maptaskr Power Maps is designed to work seamlessly with modern web-based mapping standards. This page outlines which spatial projections are supported, how uploaded files are handled, and what to expect when drawing, uploading or visualizing spatial features within the platform.

Supported Projections

Maptaskr Power Maps natively supports the following spatial reference systems:

• WGS 84 (EPSG:4326)
• Web Mercator (EPSG:3857)

These projections are standard for most modern web mapping services, including ArcGIS Online, Google Maps, and OpenStreetMap.

If a published feature service supports exporting layers in WGS 84 (EPSG:4326), Maptaskr can consume and render it without issue - even if the source data is stored in a different projection.

Using Layers in other Projections

You can use layers published in other projections as long as the service supports dynamic reprojection to WGS 84 (EPSG:4326). In such cases, Maptaskr will automatically request the layer in the correct projection.

If the service does not support reprojection, you may need to convert the dataset to WGS 84 before use or you will need to rely on Client Side reprojection

Best Practice

For maximum compatibility and performance, we recommend using WGS 84 or Web Mercator layers when configuring Maptaskr maps.

Supported File Upload Formats

Currently the map supports the following formats:

1. GeoJSON

• Extensions: .geojson containing valid GeoJSON.
• Supported geometry types: Point, MultiPoint, LineString, MultiLineString, Polygon, MultiPolygon, GeometryCollection.
  • GeometryCollection is supported but should be used sparingly—very large collections can impact rendering performance. Consider normalizing to simpler feature types when possible.
• Coordinate Reference System: Must be WGS84 (EPSG:4326). If your data is in another projection (e.g. Web Mercator / EPSG:3857) reproject before uploading.
• Properties: All feature.properties are imported. Remove unused or very large attributes to improve performance.
• Multi‑feature files: Each feature becomes part of one Shape collection with the chosen name.

Your GeoJSON must comply with the official GeoJSON specification (RFC 7946): use supported geometry types only, ensure coordinates are in WGS84 (longitude, latitude order), and provide well‑formed Feature / FeatureCollection structures with valid properties objects.

2. ESRI Shapefile (Zipped)

Upload a single .zip that contains at minimum:

• .shp – geometry
• .shx – shape index
• .dbf – attributes table
• .prj – projection definition (enables accurate reprojection to WGS84)

Guidelines:

• Zip the component files directly (do not nest them inside a folder within the zip).
• Include only one logical layer per zip. Additional shapefiles in the same archive are ignored.
• Field name length is constrained by DBF limits (often 10 chars); long names may be truncated.

3. KMZ/KML

KML (Keyhole Markup Language) is an open standard for encoding geographic data, commonly used in Google Earth and other geospatial applications. Maptaskr supports both uncompressed KML and compressed KMZ formats.

KML (.kml)

• Extensions: .kml or .kmz containing valid KML markup.
• Supported geometry types: Point, LineString, Polygon, MultiGeometry.
• Coordinate Reference System: Must be WGS84 (EPSG:4326). If your data is in another projection (e.g. Web Mercator / EPSG:3857) reproject before uploading.
• Features and properties: All KML placemarks and their associated properties (name, description, etc.) are imported as GeoJSON features.
• Styling: KML styling (colors, line width, icons) is extracted where possible and applied to the imported shapes.

File Uploads and Reprojection

When users upload spatial files to Maptaskr Power Maps (e.g. Shapefile, GeoJSON, KML, CSV), the system performs the following:

• Detects the projection of the uploaded data
• Uses the Proj4JS library to reproject it to WGS 84 (EPSG:4326) in the browser
• Renders the data on the map as GeoJSON
• Stores the original uploaded file as an attachment on the related Maptaskr Shape record

note

The original uploaded files are not modified. They remain attached to the Shape record and can be used to sync data back to authoritative systems such as ArcGIS with full spatial integrity.

This approach ensures that visualizations are rendered consistently on the map, while preserving the source data for future reference or high-precision workflows.

Recommendation

While uploaded files are reprojected in-browser for map visualization, this transformation is intended for display purposes only.

If spatial accuracy is important to your business process — such as in regulated workflows or when syncing data back to a GIS system — we recommend using Shapefile uploads (.zip) for these scenarios wherever possible.

The original uploaded file is retained as an attachment on the Shape record and should be considered the master reference for any downstream GIS provisioning or spatial analysis tasks.

Drawing Points, Lines, and Polygons

When a user draws a feature on the map:

• The geometry is captured as a GeoJSON feature in WGS 84 (EPSG:4326)
• This shape is saved as a new record in Dataverse via the Maptaskr Shape table

Maptaskr uses this standard format to maintain compatibility with external GIS systems and ensure spatial data consistency across environments.

Learn More

To understand the structure and capabilities of GeoJSON explore the official specification at geojson.org.

Use of Proj4 for File Uploads

Maptaskr Power Maps uses the Proj4JS library to reproject geospatial data during file uploads. When a user uploads a supported file (e.g. Shapefile, KML, GeoJSON, CSV), the system:

• Detects the source projection defined in the file
• Uses Proj4JS in the browser to convert the geometry to WGS 84 (EPSG:4326)
• Displays the reprojected shape as a GeoJSON feature on the map
• Retains the original uploaded file as an attachment to the Shape record in Dataverse

This allows users to visualize spatial data accurately in the map context, while preserving the original data for high-precision or authoritative workflows.

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If you need assistance or have any questions, please contact our support team.