Developer Diary 5

Welcome to the fifth developer diary for M.E.I.O.U. & Taxes 3.0: Path to Modernity. This dev diary talks about special map mode (SMM) improvements, ensuring that future M&T will have a much cleaner way to bring information to the player.

Special Map Modes
M&T 3.0 adds in a lot of interesting data, from classes to trade to production. So much data in fact, that it is rather hard to grasp it all, not to speak of keeping track of changes over time. Of course, province modifiers will show data in a concise and easily accessible way, just mouse over it and there you go. A whole slew of census events will also inform you of country-wide changes, as well as providing more specific data and other info that would not fit well into modifier tooltips.

But while these two display methods are great for data about specific places, they are not good at showing trade connections, the density and flow of population and wealth, which areas to focus your efforts on, the overall situation that you’re dealing with. In short, they do not have the scale needed to easily compare provinces, regions and countries. This is where map modes come in.

Vanilla Map Modes
EU4 has, and always had, a bunch of map modes. They are a vital part of map games, as the human brain is not very good at storing and comparing the info from hundreds of provinces. They are also important psychologically, showing a direct representation of your efforts as a certain color spreads wide, pushing other colors out. And, of course, they look good.



Special Map Modes 1.0
The current way of showing data over the whole map utilizes the trade map mode. Modifiers that influence trade value, trade power and other trade-related things are visible over provinces in the trade map mode. Combined with the ability to show custom-made modifier icons, they are capable of showing practically any information, and even showing multiple data points at the same time by having multiple modifiers in a province.

However, it's not without drawbacks. Visually, the constant square size of modifiers is quite disconcerting - they get squished together in the HRE, while in Mongolia you have to physically go out and find the modifiers. This makes comparing entire regions a bit difficult, and does not create a clean experience like regular map modes do.

And mechanically, the added modifiers create lag in the game, both in terms of calculations and in terms of visual representation. The game even tends to crash when too many modifiers are visible at the same time. Not to mention regular trade modifiers, which are necessarily also shown on the map, in some provinces really getting in the way.



Special Map Modes 2.0
For M&T 3.0, a great opportunity opened up. With production being completely reworked into provincial production slots, the basic vanilla trade goods were all but useless. Maybe they can be repurposed somehow?



As it turns out, there's nothing preventing the removal of trade good icons, all that remains is the province color. And with trade goods not being necessary for the game anymore, they can be switched around and modified without any repercussions on the game.



Instead of having fixed values and specific modifiers, the value calculation and map displaying code parts are split up. This enables a bunch of nice features, for example using math to arrange and modify the values used to assign colors, or getting the maximum value directly from the provinces, similar to how the vanilla development map mode always has the highest value in green.



It is also possible to only get the values from and color in certain provinces, like what happens when you click on a province in vanilla map modes. It won’t happen quite as fluidly, you’ll need about five clicks instead of one, but the result is similar.



With this in hand, there are some features that make special map modes, in my opinion, in some ways superior to vanilla map modes.

SMM 2.0 is completely customizable. The new special map mode menu lets you combine any data type with any value calculation, any map scope and any color scale. You have the freedom to look at specific countries, to compare only European provinces, to organize the values on a logarithmic or linear scale. The freedom to have any data shown in red to green, blue to black, rainbow colors even, and the ability to quickly change any individual setting of the map mode.





Being able to choose any color scale means that special map modes are fully usable for colorblind people. The mapmode resolution can be changed too, from 33 distinct colors at maximum down to only 5 distinct colors, which does not look as good, but makes province comparisons much easier.

At this point, a vanilla mechanic of the trade goods map mode comes in very handy. Clicking on a province will highlight all provinces with the same trade good, i.e. all provinces with that specific value range.





You can also save such a choice as a "preset", and open it later with just three clicks. This lets you design your own choice mapmodes and open them at a moment’s notice, without the hassle of going through all the individual choices every time.





Of course, there are still some issues that Special Map Modes 1.0 also had, for example the multiplayer issue of the active map mode applying to every player in the game. 2.0 has the added disadvantage of not being able to show multiple data types at the same time. There is sadly no way to circumvent these issues currently.

For performance, there is pretty much no impact on the game at all, compared to vanilla. Every province already always has a trade good, it’s just being changed. And even though there are hundreds of possible trade goods, only a single one is present in every province, showing its color without the need for extra map icons. Mapmode recalculation is also almost instantaneous, and can be updated regularly in the background without noticeable differences.