Day 146: Blast from the Past

Yesterday I finished #168, which prevents the user from seeing (in detail) sectors they haven't been to yet, only to discover that when you add them to your itinerary you still see the names (#175).

Today's subject comes from the fact that, as of earlier today, I had 42 outstanding tickets in milestone:Polish. This is the milestone I throw things in which aren't immediately necessary, but that I want to get done before I ship the game. It's got more tickets in it than any other milestone, because anytime I feel like putting something off, there it goes!

So today I finished #76, the ability to do a quicksave of a universe while you're editing it. This is invaluable because the alternative is to go all the way back to the first editor screen, save, and then immediately load up your scenario again to continue editing.

I had to make two changes in order for this to happen. First, I had to make it possible to respond to a keypress at the engine level; because the editor can be in any one of a dozen states at any time, the engine is the only place they have in common. I was already doing this with the 'kill switch' that shuts the game down (good for testing full-screen!), so I extended it to call arbitrary code in response to any button.

The second change was surprisingly easy. Games-in-progress and scenarios-being-edited, while sharing the same file format, are saved in entirely different ways. I have plans (#169) to widen that gulf even further. So if I'm going to be allowing the person running Kuiper to save the universe they're editing at any time, there needs to be a way to know that the person is, in fact, editing a universe and not playing a game.

Kuiper uses a number of gameplay displays as editors; the map and sector states are examples. Each changes its behavior if it's in "edit mode". A number of other things change if the user is editing. So each thing which cares about edit mode has its edit_mode set to true (usually in its initializer). The problem is, half of the project cares if it's in edit mode! TraderMissions did something similar, but worse; the repository itself was given to everything that needed it, which turned out to be everything. I've done it enough and had it cause enough code bloat to dub it my own personal Anti-pattern: Constantly passing objects that should be global.

So I committed one of the cardinal sins of programming: I made a global variable. It's one of those things you're supposed to do only if you know what you're doing, and usually that rules me out. This time, though, it's making life a lot easier. And that is the story of #174.

The other thing of note I did today was create the KuiSellItemsAction. No, it doesn't force the player to sell items, like I keep thinking when I see it, it puts the items you indicate up for sale on the planets you tell it to. You can sell weapons, cargo, ships, and/or addons. This is useful for, say, simulating technology advances in-game. I use it in the tutorial to only offer weapons to the player after they get the weapons tutorial.

Now taking bets on how long it'll take the global variable to bite me in the ass!