Nullkiller AI will now prefer giving its scout heroes faster units to
optimize their movement points on next turns.
Unit selection logic:
- AI prefers to give 'weak' units that won't affect army strength of main
hero. Unit is considered 'weak' if its level below 4 or if its AI value
is below 1% of total army strength. So AI can give high-tier unit to
scout, but only if main hero already has massive army.
- Within weak units, if hero is moving on terrain with penalty, AI will
always prefer units that are native to this terrain. So on snow AI will
always prefer unit from Tower even if its speed is lower than unit from
another faction.
- Within remaining candidates, AI will prefer unit that will give higher
movement points limit. This also means that in case of H3 rules, all
units with 11+ speed will be viewed as equally good
- If there are multiple units with same speed, AI will prefer unit with
lowest AI value
The score for buying army now scales with the cost of that army.
The cost of the units that need to be disbanded in order to hire the new units is subtracted from the army-hiring-score so the AI will prefer hiring armies where the amount of troops to disband is low or non-existent.
Fixed a bug that also disbanded troops when there still were free slots available.
Supressing hiring army on turn one seems just bad. Starting the main-hero as strong as possible seems like a good idea to me and hiring the available troops outright will help achieve that goal.
However, if there's a hero for hire, who has army with him that is a better deal, we hire that one first.
