SampleDataAccess - softwareunderground/xsdf GitHub Wiki
Access to the sampled data
Data access layers invariably offer different ways to access the data. Usually, you declare an 'interest', so that the underlying system can optimize access. This seems a good, universally usable strategy.
Within that 'interest' two modes are essential:
- Iteration: just handle all data in a 'natural' order (determined by the system)
- Random access: be able to inspect different parts as the situation requires
For random access, an important requirement is to be able to jump according to alternate keys.
In terms of supported subselections, it seems most important are ranged subsets (subcubes, line parts) and polylines for random lines in 3D.