Saving instance_place

[Master Cabalist]

I'm saving all my game values in a ds_map. But I came across a snag. How would I go about saving something like the following:

global.current_bat = instance_place(x, y+100, SentryBatObject);

Before I was just saving the objects, but since this variable is a reference, I don't know how to serialize it.

 

[FrostyCat]

When you save, save the instance ID alongside each instance you save, and write variables containing instances IDs as-is. As an example, this is what your save data may look like in JSON form:

{
  "instances": [
    {
      "id": 100aaa,
      ...
    },
    {
      "id": 100bbb,
      ...
    },
    ...
  ],
  "current_bat": 100aaa,
  ...
}

As you load and re-create the instances, create a map pairing the old instance ID (i.e. the one read from the saved data) and the re-created new instance ID (i.e. the corresponding one returned by instance_create_*()). Here's what the pairing map may look like in JSON form:

{
  "100aaa": 100xxx,
  "100bbb": 100yyy,
  ...
}

To finish, simply use the pairing map to translate the loaded instance ID into a re-created instance ID.

global.current_bat = pairing_map[? string(loaded_data[? "current_bat"])];

If you're going to be using maps and lists to store your data, I strongly recommend that you familiarize yourself with data modeling in MongoDB. Most of the principles work the exact same way with plain JSON, and it really isn't all that hard.