Question

I am looking now for some time about how can a programmer simulate a AI decision based on percentages of actions for the final fantasy tactic-like games (strategy game).

Say for example that the AI character has the following actions:

Attack 1: 10%
Attack 2: 9%
Magic : 4%
Move : 1%

All of this is far from equaling 100%

Now at first I though about having an array with 100 empty slots, attack would have 10 slots, attack 2 9 slots on the array. Combining random I could get the action to do then. My problem here is it is not really efficient, or doesn’t seem to be. Also important thing, what do I do if I get on an empty slot. Do I have to calculate for each character all actions based on 100% or define maybe a ‘default’ action for everyone ?

Or maybe there is a more efficient way to see all of this ? I think that percentage is the easiest way to implement an AI.

Answer 1

The best answer I can come up with is to make a list of all the possible moves you want the character to have, give each a relative value, then scale all of them to total 100%.

EDIT:

For example, here are three moves I have. I want attack and magic to be equally likely, and fleeing to be half as likely as attacking or using magic:

• attack = 20
• magic = 20
• flee = 10

This adds up to 50, so dividing each by this total gives me a fractional value (multiply by 100 for percentage):

• attack = 0.4
• magic = 0.4
• flee = 0.2

Then, I would make from this a list of cumulative values (i.e. each entry is a sum of that entry and all that came before it):

• attack = 0.4
• magic = 0.8
• flee = 1

Now, generate a random number between 0 and 1 and find the first entry in the list that is greater than or equal to that number. That is the move you make.