[2.0.76] combinator_decription / player_description and undo/redo events
Posted: Tue May 12, 2026 1:05 am
Hi,
I am trying to implement undo/redo for config changes for a custom mod based on a combinator. Currently, I am experimenting with serializing my custom configuration into a json string and store it in combinator_description/player_description. According to various posts here, there seems to be an upper limit of characters (500?) but it is not clear whether this is enforced by the GUI/editor or the engine itself. Can I store strings longer than that in this field if I never open a GUI on it / don't need it for blueprinting?
Speaking of blueprinting: A lot of the undo/redo actions provide BlueprintEntity objects that represent the entities involved (e.g. for copy-entity-settings there is the target and the entity_with_previous_settings). At some point, the engine takes a snapshot of the object that will be involved in the undo/redo operation. Would it be possible to fire an event here (e.g. on_entity_blueprinted) that would allow a mod to add elements to the blueprint entity (similar to what the "regular" blueprint operations allow)? This would be extremely helpful in storing custom information (in my case config information) that I could then use to provide undo/redo for my mod.
I am trying to implement undo/redo for config changes for a custom mod based on a combinator. Currently, I am experimenting with serializing my custom configuration into a json string and store it in combinator_description/player_description. According to various posts here, there seems to be an upper limit of characters (500?) but it is not clear whether this is enforced by the GUI/editor or the engine itself. Can I store strings longer than that in this field if I never open a GUI on it / don't need it for blueprinting?
Speaking of blueprinting: A lot of the undo/redo actions provide BlueprintEntity objects that represent the entities involved (e.g. for copy-entity-settings there is the target and the entity_with_previous_settings). At some point, the engine takes a snapshot of the object that will be involved in the undo/redo operation. Would it be possible to fire an event here (e.g. on_entity_blueprinted) that would allow a mod to add elements to the blueprint entity (similar to what the "regular" blueprint operations allow)? This would be extremely helpful in storing custom information (in my case config information) that I could then use to provide undo/redo for my mod.