Allow specifying filename (#1)

* Allow specifying filename

* Update README

README.md

@@ -8,7 +8,7 @@ This mod is still in the "alpha" phase; as such, many types of nodes are not yet
 
 ## Usage
 
-Use `/mesh1` and `/mesh2` to set the corners of the area you want exported, then use `/meshport` to export the mesh. The saved `.obj` and `.mtl` files will be located in the `meshport` folder of the world directory, within a subfolder.
+Use `/mesh1` and `/mesh2` to set the corners of the area you want exported, then use `/meshport [filename]` to export the mesh (filename is optional). The saved `.obj` and `.mtl` files will be located in the `meshport` folder of the world directory, within a subfolder.
 
 ### Importing into Blender
 

export.lua

@@ -132,7 +132,7 @@ function meshport.create_node(idx, area, content, param2, playerName)
 	return faces
 end
 
-function meshport.create_mesh(playerName, p1, p2)
+function meshport.create_mesh(playerName, p1, p2, filename)
 	meshport.print(playerName, "info", "Generating mesh...")
 	p1, p2 = vector.sort(p1, p2)
 	local vm = minetest.get_voxel_manip()
@@ -163,13 +163,21 @@ function meshport.create_mesh(playerName, p1, p2)
 		end
 	end
 
+	filename = filename or os.date("%Y-%m-%d_%H-%M-%S")
+
 	-- Create path for exported mesh.
 	local path = string.format("%s%smeshport%s%s_%s",
-		minetest.get_worldpath(), DIR_DELIM, DIR_DELIM, playerName, os.date("%Y-%m-%d_%H-%M-%S"))
+		minetest.get_worldpath(), DIR_DELIM, DIR_DELIM, playerName, filename)
+
+	if file_exists(path) then
+		meshport.print(playerName, "error", "File already exists.")
+		return
+	end
+
 	minetest.mkdir(path)
 
 	mesh:write_obj(path)
 	mesh:write_mtl(path, playerName)
 
-	meshport.print(playerName, "info", "Finished.")
+	meshport.print(playerName, "info", "Finished. Saved to " .. path)
 end

init.lua

@@ -53,8 +53,8 @@ for i = 1, 2 do
 end
 
 minetest.register_chatcommand("meshport", {
-	params = "",
+	params = "[filename]",
-	description = "Save a mesh of the selected area.",
+	description = "Save a mesh of the selected area (filename optional).",
 	privs = {meshport = true},
 
 	func = function(name, param)
@@ -63,6 +63,13 @@ minetest.register_chatcommand("meshport", {
 			return
 		end
 
-		meshport.create_mesh(name, meshport.p1[name], meshport.p2[name])
+		if param:find("[^%w-_]") then
+			meshport.print(name, "error", "Invalid name supplied. Please use valid characters ([A-Z][a-z][0-9][-_]).")
+			return
+		elseif param == "" then
+			param = nil
+		end
+
+		meshport.create_mesh(name, meshport.p1[name], meshport.p2[name], param)
 	end,
 })