I can see that the mouse is used at least in these ways on the area:
- Buttons overlaid on the tile area can be clicked and take precedence. The buttons can be any graphics, not just rectangular areas.
- Tiles can be clicked and have tile-specific behavior. However in FV the graphics of the tile define the clickable area, not the base of the tile. This means that if a high structure is in front of a back tile, that back tile cannot be clicked at all. Somehow in practice this doesn't seem to happen though, I suppose no tiles are that high.
- Clicking on a tile that has no specific behavior causes the character to move there. Movement seems to be happen in world space instead of tile space. The character moves towards the clicked spot in a bit of a random stagger, somehow still managing to avoid walking through buildings. There are such few buildings in the game that instead of pathfinding, perhaps being on top a building simply pushes the character away from it.
- Moving characters can be clicked too.
- Level can be dragged.
- Mouse cursor can change to indicate what kind of action clicking would do. In javascript this can be done by setting style.cursor.
There's also zooming, which I haven't thought about at all yet.
