Rounded terrain?

The terrain is jagged because it's drawn by connecting the randomly generated points that define the height of each chunk of terrain. It might look nicer if the terrain were rounder, but the complexity of generating this may be higher and the API calls for drawing this are less straightforward. Additionally, it would require rewriting the algorithm for tank movement, as it's currently based on the assumption of a constant gradient for each chunk.

The issue names no files or tests. Start by locating the random terrain-point generation, terrain drawing calls, and tank-movement algorithm; done means terrain appears rounder while tank movement still works correctly across terrain chunks.

Written by the indexing model from the issue text.