build feedback

src/game.lua

@@ -25,7 +25,19 @@ local function get_initial_game_state(seed)
 end
 
 local function can_do_build(hex, tile, tower_type)
-    return can_afford_tower(state.money, tower_type) and tower_is_buildable_on(hex, tile, tower_type)
+    if not can_afford_tower(state.money, tower_type) then
+        return false
+    end
+
+    if not tower_is_buildable_on(hex, tile, tower_type) then
+        local node = WIN.scene("cursor"):child(1)
+        node.color = COLORS.CLARET
+        node:action(am.tween(0.1, { color = COLORS.TRANSPARENT }))
+
+        return false
+    end
+
+    return true
 end
 
 -- initialized later, as part of the init of the toolbelt

src/tower.lua

@@ -154,7 +154,7 @@ function tower_is_buildable_on(hex, tile, tower_type)
     elseif tower_type == TOWER_TYPE.LIGHTHOUSE then
         local has_water_neighbour = false
         for _,h in pairs(hex_neighbours(hex)) do
-            local tile = HEX_MAP.get(h.x, h.y)
+            local tile = state.map.get(h.x, h.y)
 
             if tile and tile.elevation < -0.5 then
                 has_water_neighbour = true