Starcraft AI blog

Two big posts today! Antiga announced the AI Starcraft Tournament (AIST), Season 1, to be held next month. The tournament is to be played on the same professional maps as the ongoing Afreeca Starleague season 5, aka ASL5: The old map Gladiator and the new maps Sparkle, Third World, and Transistor.

I’m in favor of tournaments like this. The new maps present difficult challenges that Brood War bots have not faced before, and confronting them should force bots to become more robust and capable. The competition is labeled Season 1, so the intention is to hold more competitions in the same vein, with further tough maps. Over time, that should also impel bots to become more general and flexible. It’s good.

The deadline is soon! The submission deadline is 10 June, less than a month away. The new maps are ambitious targets for current bots, and I believe it will not be possible for authors to fully adapt their bots in time. I expect that participants will be taking shortcuts or accepting poor play.

trying out the maps

Should Steamhammer participate? The first part of the question is, can Steamhammer participate? Can it be adapted to the demanding professional maps before the deadline, or is the amount of work infeasible? I imagine I could do it if I rely on map-specific hacks (“if the map is named Sparkle, use this build order, kill this neutral building at this time, ...”), but I see hacks as wasted work that will have to be redone properly later. I want more general techniques to cope naturally with particular map features wherever they come up.

I tried the maps in test games to see what happens. In alphabetical order:

• Gladiator was fine. Steamhammer played normally. It’s a classic map from 2010, and that is what I expected.

• Sparkle, the island map, caused less trouble than I expected. Well, I expected a lot. I gave Steamhammer a game against the built-in AI (which can cope with islands), and made it ZvZ to be sure that it would go air. Drone scouting failed, obviously. The bot was unable to expand, even on its own island, and played the game with 1 base. It made a ton of zerglings (“it’s ZvZ, I know how to play this”) which had little use since they could not get off the island. The Recon squad is ground-only, so Steamhammer didn’t find enemy island expansions until after it reduced the enemy main. Steamhammer did finally win, though; the broken stuff was not absolutely essential. The problems are likely solvable by adding basic island skills, plus some map feature skills so it can recognize and take its own expansions.

• Third World caused more trouble than I expected. I thought that play would ignore the “third world” upper left part of the map, since it is reachable only by drone mineral-walking tricks, and proceed normally on the resource-poor “first world” remainder. But no, again Steamhammer was unable to expand beyond its starting base. I don’t know why. Drone scouting again failed, apparently because BWTA failed to calculate regions, or did it in some way differently than Steamhammer expects (I didn’t dig into the cause). It’s hard to say how long it might take to debug and fix or work around the issues. Every use of BWTA has to be removed eventually, but this one was going to wait....

• Transistor crashed Steamhammer’s new map analysis. I’ve tested the code on dozens of maps, from irregular Blizzard maps to intricate pro maps, and this is the first crash. The map doesn’t look technically difficult except for the weird crystals at the starting locations, and I had expected it would be OK. Likely it will turn out fine once I fix the crash.

My preliminary conclusion is that Steamhammer can play, but it will not be well adapted to the maps. I will have to spend time surviving tricky map features and won’t have much for thriving with the important play features like mineral-walking drones into the third world, or linking up island bases with nydus canals. The play features are what make it worthwhile, so I’m feeling hesitant. I’ll look into it more, though. This is only a first look, and there is more to find out.

How many participants will there be? How ready will they be? If people are saying “I suffer on these maps too, but it is still worth it” then it becomes self-fulfilling, it is still worth it.