Web Mapping
Understanding Coordinate Reference Systems A coordinate reference system (CRS) allows locating geographical features on the Earth’s surface by defining a specific map projection, coordinate system, ellipsoid and datum. The coordinate values themselves only have meaning when linked to a well-defined CRS. The two most commonly used CRSs for web mapping are: EPSG 3857 – Based…
Visualizing Spatial Data The visualization of spatial data refers to the representation of information that has a geographic or positional component through digital maps and other graphical formats. Effective visualization of spatial data enables users to explore trends, patterns, and relationships in the data through an intuitive visual interface. Key considerations when visualizing spatial data…
Understanding CORS Issues in GeoServer GeoServer is a popular open source mapping server that allows publishing and editing geospatial data. It is built on top of Java and is commonly deployed in servlet containers like Tomcat or Jetty. A common issue that arises when using GeoServer is CORS or Cross-Origin Resource Sharing errors. These errors…
Understanding CORS CORS (Cross-Origin Resource Sharing) is a mechanism that allows resources on a web page to be requested from another domain outside of the domain the resource originated from. This is necessary for GeoServer since web maps served by GeoServer are often consumed by web apps on different domains. Without CORS, browsers restrict cross-origin…
What is CORS? CORS stands for Cross-Origin Resource Sharing. It is a mechanism that allows restricted resources on a web page to be requested from another domain outside the domain from which the resource originated. CORS defines a way in which a browser and server can interact to determine whether it is safe to allow…
Understanding Complex Spatial Datasets Complex spatial datasets contain multidimensional information with geographic and temporal components. Properties that define complexity include large file sizes encompassing extensive geographic areas captured at high spatial and temporal resolutions. Common sources are satellite imagery, aerial photography, LiDAR scans, and real-time sensor networks generating vector-based files in formats like GeoJSON or…
Caching Map Tiles and Datasets for Faster Loading To improve performance of web-based geographic information systems (GIS), a common technique is to cache map tiles, vector data, and other spatial datasets in a fast in-memory store like Redis or Memcached. This avoids having to load the same data repeatedly from disk or databases, reducing latency….
Core Problem: Limited Default Print Capabilities The default print capabilities in OpenLayers are rather limited. Out-of-the-box, users can only print the main map viewport without additional customization. Key elements like map legends, scale bars, north arrows, and titles are not included by default. Furthermore, the default print output uses the web map resolution and extent….
The Need for Speed The rapid digitization of geospatial data from satellites, drones, sensors, mobile devices, and other sources has led to exponential growth in the amount of location-based information available. This deluge of real-time geospatial data has driven demand for faster processing and analysis capabilities across many industries and applications. Urban planning, transportation, energy…
Storing Massive Geospatial Datasets in the Cloud The rapid growth of geospatial data from satellites, drones, sensors, and simulations has created massive datasets that strain traditional on-premises storage infrastructure. Migrating to cloud-based storage solutions provides the scalable capacity and durability needed to cost-effectively store terabytes to petabytes of raster and vector geospatial data. Public cloud…