Direct location gives null results on a rugged region (Alps mountain)

When computing a grid of direct location on the Alps moutain region, two points give null results.

The first case dump_ALPES_i10j10 The second case dump_ALPES_i24j14

added Bug label

mentioned in commit e5cfd0ed

mentioned in commit 0e96b197

In Duvenhage algorithm, in the refineIntersection method for the DEM, some rare cases led to no intersection (as a result from SimpleTile.cellIntersection) with the closeGuess given as input of refineIntersection. By shifting the solution along the LOS direction, with an iterative process, we are able to find the intersection.

mentioned in commit 05f770cc

added Resolved label

closed via commit e5cfd0ed

closed via commit 0e96b197