Starcraft AI blog

I have given Steamhammer a primitive ability to lift terran buildings. A terran opening can include a command like "go lift engineering bay" and every ebay that can lift, will. If it’s busy researching, it can’t lift. The StrategyManager code that manages terran production will lift every barracks and ebay if the plan calls for all factory production, so the command doesn’t have much practical use for those writing openings. Still, the lifted buildings will leave more space available in the main base, so fewer factories should end up in the middle of the map.

I thought the work would be trivial, but I had to make more changes to the parser than I expected. Now a MacroAct is able to parse and remember a command with a UnitType argument, in case I ever add any more commands like that.

Floating buildings are controlled by the new Scout Boss, which will find something useful for them to do. That’s why I added lifting now. I am also looking ahead: Lifting an infested command center is a zerg skill, and I’d like to be able to do that when appropriate. Steamhammer infests command centers on a regular basis, much more often than I’ve seen any other player do, bot or human.

You’ll need to write code if you want to lift off a specific building: Just this ebay that I built forward for scouting, not the one at home. A simple command has no way to specify. Still, I would like the production system to be able to tie production to specific units: Morph these hydras to lurkers, not the others; make this creep colony into a spore and that one into a sunken. I’ve seen only one game where it tried to make a spore (in main) and sunken (at natural) at the same time and got them switched, but it seems like something I had better get right.

Landing is not as easy as lifting off, because you have to decide where to land, and it depends on what you’re aiming for. Someday I’ll implement lifting off an endangered building and landing it again when the area is safe. It may involve ordering your own units out of the landing zone. That will likely be the first use case for landing. I think other cases will wait until there is an operations planner: Opening and closing “gates” in a wall, relocating a command center, floating in a proxy factory, reacting to enemy tricks like blocking the machine shop with a pylon....