Simultaneous Turns

Started by
6 comments, last by Iron Chef Carnage 15 years, 9 months ago
Could anyone point me in the direction of some resources on the mechanics of how to do turn-based games that have simultaneous turns, that is, where each player submits their moves, then all moves are resolved at the same time at the end of the turn? I'm looking for something on how to resolve the different combinations of possibly conflicting moves.
Advertisement
1: player orders their units, units have list to store orders
2: repeat for all players
3: make list of all units and sort by initiative score + random
4: pop unit from list and have it carry out its orders
You would probably have to choose a method of how to order in which all the characters would be handled(by speed, or something similar). With that you could go through all of the characters and allow each one to make a decision that doesn't conflict with those previously made. Or you could let them all make their decisions and then have them act on them in order. That way the slower characters would be the one's who get cut off(of course that wouldn't be a very friendly system).
There was a PS1 RPG that had turn based tactical combat like that, to an extent. You gave the orders, and the character whose turn it was moved along with whoever the enemy was next in line. Got frustrating really quickly since the AI couldn't be bothered to track enemy movements; and thus orders to attack were usually turned into swings at empty air, for both sides. After about 30 minuets of two characters circling each other and attacking (you couldn't seem to attack directly; as the AI ALWAYS moved the NPC to another position before attacking), I tossed the game in a box, and never played again.

Most games I've seen don't have true simultaneous turns. They may allow the player(s) and AI to give orders at the same time, but it's acted on in order of who makes the orders first.

An alternative is to have an order phase, which the player(s) all give their orders to each units, then a action phase, which all units act on those orders at once. However, you'll still run into the above problem unless the AI is able to track enemy movements, and adjust your orders to compensate (i.e. a unit ordered to attack another chases that unit and attacks, irrespective of the target unit's starting or ending location on the map).

Another is that all orders are acted on as they are given, and the 'turn' resets the move points, and whatever else your design calls for. This pushes more into RTS territory, however; with the addition of a forced pause in between the turns. It's also resource-intensive, though nowadays that really isn't much an issue. RTS games are even more intensive, and they run fine for the most part.
I've played the demo of turn-based game, I can't remember the name but it was between three and five years ago, where turns were taken simultaneously, but you could only move your units through and into hexes that you had more 'control' over than your opponent. There was no direct conflict, only the shifting of borders in strategic fashions. After both players declare end-of-turn or reach the time limit, borders are updated, and each player is shown the new game state, being pieces and borders. You only see what your opponent just did, you can't wait and watch them move, and then make your own counter-moves. This was reinforced by the fact that the game had a play-by-email mode (with time limit disabled), where you trade save-files after you finish your turns.

The trick to the game was strategic control; there was a small, expensive piece that moved quickly, but didn't support your border; it just prevented your enemy from moving to where it stood. There were pieces with restricted movement patterns, but which had strong local effect on your border. And there were pieces with moderate initial movement which could be turned into a marker stone by their owner to create a small patch of permanent border, destroyable only by the last class of unit; border hoppers who could move into enemy territory only to destroy an enemy piece which you know cannot move this turn (whether by being a marker, or by being trapped).
RIP GameDev.net: launched 2 unusably-broken forum engines in as many years, and now has ceased operating as a forum at all, happy to remain naught but an advertising platform with an attached social media presense, headed by a staff who by their own admission have no idea what their userbase wants or expects.Here's to the good times; shame they exist in the past.
Look into the combat systems of most table top rpgs or strategy games



here are two systems that i can think of off the top of my head

system 1

have a initiative phase at the beginning of the game where players given an random number then run the order of the commands based on the player initiative.

during a the turn you have a command phase and that is when all the orders are given
then you have an action phase where all the orders are carried out

system 2

at the beginning of each turn generate initiative for each player or object that can move and have those objects/players take precedence

this method is based on the first but initiative is generated every turn

then acts like the first system
commands are given then actions are taken in the order of initiative
0))))))>|FritzMar>
You might want to have a look at the rules for Diplomacy, a boardgame where the rules for combat resolution are constructed in such a way that the order of moves does not play a role.
This has come up before on these forums, you might be able to come up with some search results that help.

I remember two noteworthy schools of thought on the topic.

Interrupt/Resume: Everyone gets a "move" command issued, and these are all carried out simultaneously. If, during the "move" phase of the round a character is put into an "encounter" situation, then you pick an action. So if my Marine is running toward a dropship and the other guy's hydralisk moves out from behind a rock, the action pauses at the moment my guy notices the enemy, and I can choose to spend my action move then and there to shoot at the thing, or to keep running, or to start running a different direction. Then the round resumes, and the action is carried out. When the enemy spots me (possibly because I'm shooting his face), the action pauses again and the other guy makes his move to attack or move. After the full move command is completed, everyone gets their action points back, gives their dudes a new move order and it kicks off again. Silent storm, though not simultaneous turns, has an interrupt feature that depends on the action points you conserved last turn. If your sniper has been sitting at his perch and has all his AP, then he gets a full interrupt turn when a bad guy blunders into his line of sight. If he's been running, then he just gets to see the other guy's position. If the other guy's all stealthy and you fail the perception test, then you don't get a turn at all.

Magic AI: The miraculous AI system allows commands to be more a matter of intention and mindset, and then the characters take care of business. Tell your guy to go from his foxhole to the abandoned church *sneakily* and he'll creep out, worm across the yard, duck in the back and hide in a corner. Tell him to *go like hell* and he'll jump up, sprint across the open space and dive through the stained-glass window with a shoulder roll and a submachinegun in each hand. If he encounters a bad guy en route, he'll engage according to operational parameters.

The way you handle it should depend on--among other things--the number of units on the board. If you've just got one character per player, the interruption method wouldn't be too aggravating, but if you've got to stutter through 47 different action turns per round, someone's going to get stabbed.

This topic is closed to new replies.

Advertisement