I don’t completely agree with the “active vs passive” distinction. “Active” resources are not purely based on the number of harvesters, but also harvester efficiency. As you add more harvesters to a location, each becomes less efficient. This (in addition to resources running out) does force you to expand to other areas. It adds the strategic decision: “do I stay here where it’s safe and try to build up enough to defeat my opponent, or do I risk defeat to expand quickly to get more efficiency from my harvesters, and thus more resources.”

Also, a note of Empire Earth’s 10 resource types. You mention that they aren’t all available at the same time, but then dismiss them for not adding strategy. They in fact do, by making the map more dynamic. The areas you want to defend early on (say, gold mines) aren’t the same areas you need to control later (eg oil). So, the map changes throughout the game, and you need to adjust your strategy in turn. (I still agree that the added complexity isn’t worth it in this case). Destructible rocks in Starcraft 2 are another example of making the map more dynamic.

Resources are divided up by how they fit into three categories:
Destructive/non-destructive: A destructive resource damages terrain when it is collected. Destructive resources are limited by the amount of the resource can fit on the map. An example of a destructive resource is wood from Age of Empires, or Tiberium from C&C. An example of a non-destructive resource is ammo from Company of Heroes.
Cumulative/non-cumulative: A cumulative resource is a resource which you get more of if you don’t spend it. An example of a cumulative resource is money from C&C Red Alert 2. An example of a non-cumulative resource is any population cap, or power from the C&C series of games.

Erm… My 2 cents.

This blog is like a big meal for my starving and thirsty RTS game theory

I almost cry by remembering, not Dune 2, but Nether Earth: this was the real first RTS game in computer history.

Have a look at it
http://www.youtube.com/watch?v=OjQXAeB6zpU
http://en.wikipedia.org/wiki/Nether_Earth

My favorite unique features of this game was:
1. capture factories to increase resources
2. factories could be destroyed (resource sources can be destroyed)
3. give orders robots: search & destroy, destroy enemy factories, capture enemy factories, etc… (AI?!?)

BTW, i’m developing a web-based RTS. If you want to share any ideas contact me at taviroquai@gmail.com

The player must decide how much to invest into each ressource.

Also, you misspelled “saltpeter”.

About the Vespene Gas thing… I haven’t played the SC2 alpha, but I’ve been reading that the vespene geysers “shuts down” when you’ve collected 300 gas. They turn on again after a certain delay, but the whole thing is just silly!

/jeb

That said, I disagree active systems are inherently better for the player, especially on the statement that active income is limited by the number of harvesters, because more often than not the game designers limit the number of harvesters capable of recollecting the resources at a given point.

As an example, Vespene Gas in starcraft can only have a single unit harvesting it at the given point, and the optimal number of harvesters assigned to a Vespene Factory, assuming the drop point is the closest possible, is just three. Any more units will just make a larger queue, but not faster recollection.

This system has also the disadvantage that you have to invest into harvesters, and given how often those harvesters also act as the builders for structures, you constantly have to pressure yourself to decide wether to recollect or build, and in faster paced games, that decision is horribly crucial to just ignore it.

Also, the number of resources to collect don’t necessarilly make a game more confusing. Prime example would be Rise of Nations, where the emerging economy truly adds for a more strategic planning for the player, and tie quite well with how the economy in the world progressed.

The closest I can think of for a single resource system with a discrete investment is Dawn of War with the Necrons – unlike the other players, they just need to recollect Power (which is generated atuomatically by creating a Power Generator) to invest in your army and your technologies, although they compensated this by giving them horrible build times to their units unless they capture locations (that other factions utilize for recollecting the Requisition resource), which speed their build times. Sadly, the system is quite innefficient, as Power recollection by means of its own consumption kind of complicates the management (which you could argue are compensated by the fact that Necrons have a very linear tech tree).

Despite my so-called counter-arguments, I admit that the economy model of most RTS is a little too flawed and quite abstracted out to simplistic numbers in the long term. I have not played Harvest yet, but what i have read about the economy model strikes me as very interesting, and even closer to reality. I really wish the economy models of certain city building games inflenced a little more RTS game designers.

As Urre says, Z has an especial system of rules that we can consider as some form of resource. I remember another kind-of-old RTS, 7th Legion, in which you’re rewarded credits for each enemy unit you destroy. Als the game featured special powers in the form of “cards” that were given randomly a bit like what happens with darwinia/multinia.

While this systems are indeed interesting, I also think it would be wise to analyze what design implications come along with them, and how affects gameplay an the type of game you want to create, or end up creating at least.
Just as you analyzed the active/passive resources, and continue/discrete resources, the game rules in Z & 7th Legion have a general inmediacy that -at least in my opinion- favors rushing. Just like the games of massive entertainment adopt some kind of puzzle-like gameplay -haven’t played World in Conflict, but for what I’ve read expands on the principles of the ground control series (btw i think you can still DL the first game from fileplaent for free if you want to try it) and that is: given an scenario, objectives & a couple of units, you have to ’solve’ the level. Yes, there are several strategies & tactics you can use (purchasing special weapons, unit types, or more dropships) but you have a game that plays waaay more slowly that the Z series in comparison.

All in all, both games can be considered RTS; and more or less any strategy game posses one kind of resource to apply in some sort of way, even in the classic turn-based ‘wargames’ which also offers the puzzle-like gameplay: isn’t action points, time managment and turns actiong like some kind of currency that effectively alters the way the game is designed & played?

They are questions related to creating, designing a game, and they came with no clear answers.
which are the game’s rules? are the game’s rules creating waht type of experience? does any of that rules covers a resource system? how does the resources work?
Finally, I’ve found that paying attention to how some board games are designed can also give pretty important clues on how to understand a good set of rules which can then be somewhat applied to computer games.

PS: sorry for the bad english if applies! kinda lost some practice with the language ;-p cheers!

I agree Harvest makes a great example of how resources can be represented in the games in other ways than a stash value in the interface. I believe it is also an example of how the line between resources and units may be thin or blurred. With another (though probably less fitting) graphical representation, the energy clusters could instead be autonomously working drones. If so, would we consider them units instead? Would they stop being a resource if we had some kind of limited direct control over them?

I don’t completely agree that more resources necessarily adds strategy options while also adding confusion. What if each resource could be spent in one or a few possible ways, and your abilbity to harvest them depends on your tech level or on spending other resources in trade? The early resources may be phased out because the source dries up or because you reach a limit for how much of it you can spend in a meaningful way. This all would drive you to adapt your strategies in an inevitable but still dynamic way, while keeping your options down to a number you could handle and appreciate.

We should talk more about this over a beer some day!