Fancying Pennywise (!)

I've often defending people's right to fancy fictional villains for various reasons. Often more interesting, less heteronormative, being specially picked by misanthropic character, just what people happen to like, etc. Assuming people keep fantasy separate, and understand what traits might be fun in fantasy but not good for a real life partner.

But I was shocked when this apparently started to include Pennywise from IT. In my head, he's a vile concoction of racism and child abuse. Roughly "rotten vomit in human form". And horribly unpleasant and obnoxious in person as well. I'm not surprised that ANYONE could be drawn to that, but I was shocked that just random people on my tumblr feed were. I'm I'm not sure, was he portrayed less vilely in the film?

Or was I just too willing to overlook characters who did really bad things but were less up in your face about it? It's a common trope of a sympathetic villain who the audience loses sympathy for when they do something particularly bad, even if in theory they've done even worse things before but not to characters the audience were rooting for. Like, many regular villains probably killed way more people than Pennywise, but I wasn't previously shocked they show up in pairings in fanfic *some* of the time.

Data structures and stuff

The premise

I have a tile-based computer adventure game. The current state is represented in memory as a 2d array of tiles representing the play area, each with one (or possibly more) objects on that tile. There is also an "undo" history, tracking recent actions, and the difference (objects moved, removed or added) so the previous or following state can be recreated.

In addition, each object remembers the most recent undo step which affected it, so you can click "undo" on an object and return it to the previous state (also undoing any following actions), not just undo one at a time until you rewind to the appropriate point.

I need to check the code, but as I remember, this is represented by each object having a pointer (well, the python equivalent) to one of the elements of the undo sequence. And when you redo or undo the pointers are updated to refer to the newly-correct object.

Now I'm unsure, but IIRC the undo steps refer to an object by coordinates in the play area, not a pointer to the object (in general, we assume the play area might store game objects as just ids or something, not as ab object in memory).

What happens when we want to save the game

We need to be able to save the game -- indeed, a modern game (especially one where actions aren't irreversible) should just save as it goes along, not require a separate load/save action to do so.

This means my instinctive layout above doesn't work. You can't save "a pointer". The best option is probably to use an index into the undo list which the undo list understands.

That can also cut out other possible bugs. If you have a pointer, it could be anywhere in memory. If you have an index into the undo list, you can choose to have the list check that the dereference is valid (and retain the option to turn those checks off if performance matters).

There's other possibilities but I think that's the best one. It is uncomfortably close to designing our own ORM -- we could alternatively have ALL objects represented by a unique id and index things by that instead (either via some global list of ids or only when we load from disk).

I run into this often when I'm game programming, the best way of 'referring' somehow to another game object -- by value or reference? by game coordinates or pointer to memory? But not in other types of programming. Does this experience ring a bell to anyone else?

But now I'm thinking...

This also reminds me of a problem I ran into when I started thinking about rust's memory models. If you have a class, that creates a bunch of other classes, and those classes want to have pointers to each other, there's no easy way of doing it iirc.

I think you need to rely on reference-counted pointers even though it feels like you shouldn't. That's not a problem in practice -- the "store an index" method above also has an indirection every time you need to access the object. But it feels like, you shouldn't need to. And a similar sort of "I want to refer to one of the classes which this big class is responsible for".

But I'm not sure if there's a way of combining these thoughts.