azavea/geotrellis — pull request #317 by ahinz (2013-01-18 06:53:27+00:00)
Title: Add new Cost-Distance Operation

This operation includes the benchmarking suite as well as a spec test. The algorithm implemented is a simple fan-out using a priority queue. I know that Dana Tomlin has done some awesome research and it would be great to integrate that at some point but I think this is a good start.

The benchmarks vary a bit since they use randomly generated data but usually a 2000x2000 raster can be processed in about 4.5 seconds.

```
rasterSize ms linear runtime
64 6.21 =
128 17.57 =
256 69.92 =
512 289.77 =
1024 1214.21 ======
2048 5338.41 ==============================
```