shift-click mineral walk trick
I learned a new trick from watching the ASL 11 games. The game was Sharp versus Best, the second game of group B in the round of 16. Watch with English commentary by Nyoken and Scan on Afreeca or on Youtube. On the Afreeca vod, the game starts a little after 55 minutes in. The Youtube vod was trimmed and it starts closer to 46 minutes.
Sharp scouted Best’s base with an SCV, which then left the base. Best blocked the entrance to his main with a zealot to prevent further scouting. But when the SCV returned for a second look, it mineral-walked through Best’s blocking zealot and got a look around anyway. I was surprised, and Nyoken (who knows more about Starcraft than I do) was also surprised: How did the SCV get vision of Best’s minerals to do the mineral walk? Sharp had no apparent way to see the minerals.
Scan explained it. The SCV was click-moved to a location far from the base (a location chosen so that the second-scout timing would come out right). As it was leaving, while it still had vision of the minerals, Sharp shift-clicked back to the minerals. That was the last time Sharp had the necessary vision. The SCV followed its orders to move far away, then followed the queued order to mineral walk back into the base. I had never seen it before.
I sometimes see bots using queued commands to move units across the map through waypoints. (In BWAPI you do that by setting the optional shiftQueueCommand parameter of a command to true; it defaults to false.) It is usually a mistake. When you queue a move command, the moving unit completes the command by coming to a stop at the destination before the next command in the queue executes. It adds a delay—a very visible delay. If you’re following waypoints, it is normally better to issue a new move command in real time before the unit reaches the waypoint, so that it never slows down or stops, and reaches its final destination sooner. But in the case of mineral walk, you may not still have vision of the minerals later when it’s time to issue that command. If you want to issue a sequence of moves ending with a mineral walk, you may want to queue them all while you still have vision. It will execute later whether you have vision then or not.
I tried it myself, and it works. What a complicated game!
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Bytekeeper on :
This is not a plea for ML, I find the overall topic rather "hyped".
Still, I consider a combination of MCTS + learned policies to be the best possible solution with current technology (well AlphaStar is more or less using this approach).
So, the search, resp. simulation part is rather "easy" (hard in its own way). The interesting thing here is the policy that would decide on where to send the worker.
Using a NN here is possible, but it might takes ages for it to learn that it is mostly not important, where the worker should be sent before the shift-return. But the timing would not be. This is more or less also the AlphaStar approach: Play multiple human lifetime worth of games.
Ok I am ranting here, but it is rather interesting how humans can learn "patterns" by applying patterns to the learning.
Dan on :
Jay Scott on :
Just as many bot behaviors are difficult to notice. So much is happening in a Broodwar game that it’s hard to follow much of it.
Dan on :
Jay Scott on :
Antiga / Iruian on :
Jay Scott on :