Automap does not work correctly for staggered maps

[eishiya]

(This is a known problem, but there did not appear to be an issue open for it. Now there is.)

Automapping only works correctly for orthographic and non-staggered isometric maps. Automapping should take staggering into account and work for all supported orientations.

Supporting multiple orientations would open up some UX issues:

• What should happen if automap rules with a different projection from the map are applied? Should rule files with incompatible projections be ignored? Should rule files be interpreted as being of whatever orientation the target map has?
• What about the same projection (e.g. iso) but different orientations, e.g. staggered vs non-staggered, or hex with different stagger indices or axes? Should these be ignored? Should the algorithm attempt a conversion to produce visually consistent results? Can that even be done reliably?
• How and when should the user be warned if some of their rules are ignored or reinterpreted due to incompatibility?

For all of these, I suppose the answers should be consistent with whatever is done when attempting to paste across maps with different orientations.

Tiled has some issues with different stagger values (e.g. #2874), those should probably be tackled first to avoid those bugs propagating into Automap.

[bjorn]

Automapping does work on isometric maps, so I've adjusted the title. Only the staggering breaks the matching.

When using right-click-drag to capture an area from a staggered map, you can paint with this brush anywhere without problems. This works because the Stamp Brush adjusts the stamp based on the location where it is used. But this adjustment is implemented only there, so it's broken for the fill tools for example (you get the same pattern only half of the time). Maybe the adjustment could be factored out of the Stamp Brush, so that it could be reused also by the fill tools and the Automapping.