iTechCostModifier, change the base cost of all techs within an era regardless of what era any players are in, it never stopped working.
So the prehistoric era iTechCostModifier will affect the base cost of:
• All Prehistoric techs
The Ancient era iTechCostModifier will affect the base cost of
• All Ancient techs
etc.
iResearchPercent, change the cost of all techs in the game for the player that are inside the era.
So the prehistoric era iResearchPercent will affect the cost of:
• All prehistoric techs
• Sedentary lifestyle tech
• (It also affects the cost of all the later techs, but this is effectively a lie as another era iResearchPercent will take over at Sedentary Lifestyle.)
When a player reach Ancient era the iResearchPercent from that era will take over and it will affect the cost of:
• All prehistoric & Ancient Techs.
• Classical lifestyle tech.
• (It also affects the cost of all the later techs, but this is effectively a lie as another era iResearchPercent will take over at Classical Lifestyle.)
Etc.
The values of the tags and defines listed below have been normalized for simplicity, meaning that there won't be any divided by 100 or +/- 1 in the equations.
[Cumulative Tech Modifier] = ( iResearchPercent WorldInfo ) + ( iResearchPercent EraInfo ) + ( iResearchPercent HandicapInfo ) + ( iBeelineStingsTechCostModifier EraInfo )
[Base tech cost] = ( iCost TechInfo ) x ( TECH_COST_MODIFIER ) x ( iTechCostModifier EraInfo, depends on what era the tech is in )
[Tech Cost] = [Base tech cost] x [Cumulative Tech Modifier] x ( iResearchPercent GamespeedInfo ) x ( TECH_COST_EXTRA_TEAM_MEMBER_MODIFIER )