Which NPC gets to move first?

[nonzerozen]

My understanding of writing a game loop is that you have to loop through all the objects who need to react and update each loop. Looping though a collection of something usually implies an order of execution.

When making a sports simulation game where all the players are NPCs, who gets to move first or last can have significant tactical advantages/disadvantages. In real life we move and act independently and in real time,

but with a game loop the NPCs are at the mercy of the developer and the order they choose.

So my question is, how do you decide which NPC gets to move/react first?

[mattstyles]

Why can't you move all simultaneously? This has the added advantage of making your collision detection better too usually. Having them all act on the same state is fairly easy to achieve, you then apply all the transformations in one go at the end to update the state, reconciling any conflicts at this point.

[nonzerozen]

I really don't understand.

Are you saying I could add some kind of "Can I do this?" step first based on the current state, and then execute a "Let's do this" step to update the state?

Please clarify because I can't really comprehend.

[mattstyles]

Yeah, exactly, if the order of updates is causing issues then split up the processing exactly how you're thinking.

When you first iterate over your list of units they all operate on the exact same state so order becomes irrelevant and when you apply the changes, again, the order becomes irrelevant.

[nonzerozen]

Right. Because the NPCs are not rendered individually in individual game loops. They are all rendered in the same loop iteration. It doesn't matter which one gets to update itself based on the current state, because they will all update based on the same state, at the same iteration of the game loop. So it really isn't an issue.

Obviously. 

Thanks. Don't know what I was thinking.