Screenshots

Import shapefiles and calculate areas and perimeters using longitude/latitude or a user defined coordinate system.

Import selected polygons from OpenStreetMap, display a raster image as background and generate reports for polygon groups.

Allocate Pt values to a user specified grid and generate reports based on the Pt data allocation.

Generate contours based on Pt data

Using the Polygon Reduction operation, the number of points for this polygon is reduced by a factor of about 4, which greatly reduces the area calculation time. Note the perimeter result is affected significantly but the area result is not (< 1%).

An example of how a pin map can easily be created in TdhGIS, as explained in the tutorial "Create a Map Showing Pinned Locations".