Spatial reference systems
What is a spatial reference system?
Section titled “What is a spatial reference system?”A spatial reference system (SRS) or coordinate reference system (CRS) is a coordinate-based local, regional or global system used to locate geographical entities. A spatial reference system defines a map projection, as well as transformations between different spatial reference systems.
Understanding map projections
Section titled “Understanding map projections”A map projection is how we represent the curved ellipsoidal Earth surface onto a flat surface - from three-dimensions to two-dimensions. It is a well known topic when presenting geographical entities. There are many different map projections, such as Mercator, Robinson, and Van der Grinten to name a few. Each projection distorts the three-dimensional surface slightly differently.
Civillo converts each layer’s data into the Web Mercator Projection, which is a variant of the Mercator projection and is used primarily in Web-based mapping programs. To complete this conversion, Civillo needs to know how the incoming data is projected so that it can perform the correct conversion process.
A list of spatial reference systems can be found at www.spatialreference.org
Assigning a project spatial reference system
Section titled “Assigning a project spatial reference system”Civillo should have a default spatial reference system. This is set when the project is created.
Users can see this spatial reference system in the feature identify tool.
