I want to create a tile-based map system like in those old (isometric) 2D games, like a grid of tiles. The terrain itself does not necessarily need to be made of tiles, it may be one mesh, however, visually it should look like as if made of tiles. In any case I would like to add a grid overlay to indicate these tiles, to do things like highlighting tiles when selecting them with the mouse (e.g. in a map editor) etc.
First I tried it with single mesh actors for each tile, but that leads to very poor performance with large maps (10.000+ tiles / grid cells). Then I tried instanced static meshes, but that turned out to be a “mess” (i.e. way too much overhead to manage those instances). It feels that both these approaches are not the best way to go, at least my guts tell me to not cut the terrain into thousands of tiles. So I am asking you guys, if I use just one single terrain mesh for the whole map, how can I make it look like made of tiles? How can I add grid overlays and highlight one or more more cells/tiles?
Just as a reference, what I am trying to achieve is something like this:
You can see the grid, even though the whole terrain seems to be made of one mesh …