Understanding computational geometry

Computational geometry encompasses the algorithms that are needed to perform operations on vector data. The field is very old in computer science; however, most of the libraries used for geospatial operations are separate from computer graphics libraries because of geospatial coordinate systems. As described toward the end of Chapter 1, Learning about Geospatial Analysis with Python, computer screen coordinates are almost always expressed in positive numbers, while geospatial coordinate systems often use negative numbers when they’re moving west and south.

Several different geospatial libraries fit into this category, but they also serve a wide range of uses, from spatial selection to rendering. It should be noted that some features of GDAL that were described previously move it beyond the category of data access, and into the realm of computational geometry. But it was included in the former category because that is its primary purpose...