Add remote interface to allow other mods to query / change sprites in… (#20)

* Add remote interface to allow other mods to query / change sprites in display frames
* update map marker if present

control.lua

@@ -478,6 +478,33 @@ local function set_up_display_from_ghost(entity,tags)
 	end
 end
 
+remote.add_interface(
+    "IndustrialDisplayPlates",
+    {
+        get_sprite = function(event)
+            if event and event.entity and event.entity.valid then
+                local spritetype, spritename = get_render_sprite_info(event.entity)
+                return {spritetype=spritetype, spritename=spritename}
+            else
+                return nil
+            end
+        end,
+
+        set_sprite = function(event)
+            if event and event.entity and event.entity.valid and event.sprite and game.is_valid_sprite_path(event.sprite) then
+                destroy_render(event.entity)
+                render_overlay_sprite(event.entity, event.sprite)
+                if get_has_map_marker(event.entity) then
+                    local spritetype, spritename = get_render_sprite_info(event.entity)
+					change_map_markers(event.entity, spritetype, spritename)
+                end
+            end
+        end
+
+    }
+
+)
+
 -- local function reset_globals()
 	-- global.translations = nil
 -- end