Design decision - Rivers - In square or on edge of square?

[Lord God Jinnai]

Actually if were doing polygon ie 'triangular-based' i have no porblem with them being on the edges. However for movement purposes up/down river we'd need some work on those calculations to be special.

[Gary Thomas]

It would just be easier to have skinny polygons for the rivers, so they would be treated just like sea polygons.

Cheers

[LDiCesare]

It would just be easier to have skinny polygons for the rivers, so they would be treated just like sea polygons.

That is the best point you have for polygons IMO. That way, we'd be rid of this whole discussion, and the movement coding would be easier.
If we have rivers on edges, we could try to track rivers outside the square data, as a separate "map". That way we could have distinct objects for distinct rivers (west edge, east edge).

[Mark_Everson]

Polygons may be a viable long-term solution. But until we get other things that are Much more important than rivers (Technology, Social Model, Diplomacy...) working in the game I believe any refactoring of the square-based system is premature.

I would rather forget rivers completely for quite some time than embark on the massive changes in the code and map art that a move to polygons would entail. Major code changes would include movement AI in addition to the obvious movement code changes.

That said, in the long term polygons are looking more attractive!


Back to the square world, which I believe we're stuck with for a bit...

I'm now leaning toward square-edge rivers. It seems they on balance will allow a more rich environment visually, and for game effects. How about others of the old in-square group? Can you look over this thread and the rivers one again, and see if you're persuaded that square-edge is at least as viable as in-square rivers.

Or if you want to cast a vote for polygons, that's fine too, although then I propose we then shelve rivers for the forseeable future until several other refactoring projects are done, and the game has progressed quite a bit.

Cya,

Mark

[HugoHillbilly]

My vote would go to rivers on the edges of the squares. Personally I never liked the bonus movement given to units to simulate boat travel on rivers, or the fact they were allowed to cross them. Since Clash will incorporate Ships on rivers (if I have read correctly) then this movement bonus isnt needed. Plus rivers make good natural boundaries in the early game until bridging is discovered.

Graphics-wise, Civ3 has rivers on the edges of squares and they look very nice. As for cities on rivers, I dont see how it will be any different if the river is in the square or on the edge.

I also feel combat could be handled more realistically with rivers on the edge.

On another note, will damming rivers to flood cities/strongholds be incorporated into the combat model? I have seen this in some TBS games and implemented properly could be a fun alternative to the typical siege of enemy positions.

[sas]

I think rivers on the edge is the best solution. Originally i thought rivers in the middle "felt" more natural. But after reading the arguments for putting rivers on the edge, it seems like the best solution.

[LDiCesare]

I'm in for rivers as polygons. This means edge rivers actually, since it would be funny to have two polygons overlapping. I am not eager to see coding of the edges right now however, if we ever go towards polygons, since that means I need much more info to be stored in MovementData.
Gary, now I think you can rejoice.

[Gary Thomas]

Now that I am back on air (I lost the ability to post for a while), I guess I can. For a while I felt that I was swimming upriver, against a strong current...

As I have said pretty much from the beginning, my main reason for wanting edge rivers is to make them barriers.

Now, of course, we have to think about navigable rivers, fords, bridges, floods.

My head hurts.

Cheers

[Plutarck]

I'm attaching a screenshot of Civ3, which uses edge-rivers. Note that the art for my cute little palm tree (in the desert), the rivers, the "goody huts" (those fort-type things), the jungles, the forests, and partially the rocky-mountains were done by fans of Civ3, not Firaxis. The originals weren't as pretty, in my opinion, but the original rivers didn't have such dark green borders. The creator added that so they were easier to see.


Now, I think that addresses it from a graphical perspective, but if I may state my opinion on the gameplay aspects.


First of all, I can't think of any "good" way of handling a unit..err, "TF", that would be "between" squares, which is where it would have to be to be in the river. Otherwise it would have the appearance that a trireme had sprouted feet or been equiped with wheels and was traversing the land. While certainly an interesting - if not anachronistic - thought, it would snap suspension of belief right quick. More than that, it would be just plain silly.

Otherwise the boat would have to be placed between squares, which would mean that the game wouldn't be able to simply store a set of tile coordinates (X and Y, unless Z came into use), but rather would have to manage to store some variant of absolute coordinates or "Between X,Y and X,Y" tile coords. And to display the boat it would have to be really puny so as not to obscure neighboring squares, and no matter how small it was it would do that to some degree. This seems to fall into the "more trouble than it's worth" category.

Thus, if I may, I would like to propose the following:

Edge-rivers will hold no "visible" units. However, citys which share a connection via river would be considered to be connected by a road for communication purposes (if rivers aren't even considered faster than roads). While no Task Force level units would be able to take such a transportation system, a messenger on a raft/in a canoe could clearly paddle about, as well as independent citizens.

The reason the river would be displayed is not so much because of it's size, but because it has a single flow over a long distance. So you could get on the river and travel along it without ever having to get off, carry your boat over to another river, then continue the journey. Anything smaller would be considered a brook, and too small to bother attempting to represent.

But the river would be considered too "small" for significant levels of cargo, so at most a small "trade" bonus could be given to each city for the river connection, but that's about all. And tiles that border the river will get a trade bonus (in the Civ3 style of Food, Production, and Commerce, all tiles bordering a river get +1 commerce regardless of terrain type).

Now, just because there are edge-rivers doesn't mean there can't be fordable "river squares" as a terrain type. The tile would represent some river big enough to support significant shipping, such as the Nile, and unlike a river - which can just pop out of a hill/mountain and start flowing accross the lanscape - such a major river would be fed by a more significant body of water, such as a lake.

This River Terrain would be treated with special rules, and not every kind of TF can just go across on it's own. For one, there could be fordable and non-fordable types. The non-fordable would require the presence of a friendly boat on the river, and TFs would use the boat as if it were a bridge. Or there could be bridging-troops (whether modern types or just guys who fashion together some rafts or some rope-lines). This could be controlled by Bridging technology, if it would be desirable.

The River Square would be mostly water with bits of land on each side (graphics drawn using a gradient is probably best...more on that towards the end).

It would be a barrier in the sense that, unless fordable, it flat-out can't be crossed without aforementioned assistance. If you try to cross and you end up in the river with an enemy on the other side, it could get ugly - you should probably have the option whether or not to retreat, and if the enemy has missle troops they could pelt you as you ran away, or even chase you into the river. Where's Moses when you really need him?

No city could be built on it, unless Floating Citys are allowed. Maybe only for The Frog People.

A bridge could be constructed, and there could be multiple kinds of bridges. You could build a dam-bridge which blocking travel along the river, or a bridge that allowed enough clearance for small boats to pass under (nothing with a mast), or even a draw bridge kind of deal.

All could simply be handled with an overlay, like roads and rivers (layers surely are much easier to handle, which is how Civ3 does it, and probably most other edge-river computer games).

Canals are certainly interesting, but I believe they can be handled entirely sepperately from this issue. Although I believe they would fit perfectly into the in-square river terrain, there are plenty other "models" they will fit just fine into. Thus I propose that the issue be considered inconsequential to this particular decision.



In conclusion, it is my proposal that in-square rivers and square-edge rivers are not at all mutually exclusive; in fact, in-square rivers should just be a special terrain type (much like in Civ2, but with more "specialness" in how they're handled), while square-edge rivers should be an overlay, suitable for barriers to movement, cross-river defensive bonuses, possible death resulting from crossing a dangerous river, an economic bonus to tiles bordering them, and perhaps a road-like bonus to communication/trade between connected citys (but not TF movement).



Thank you,
Plutarck


Note: I'll try and post the screeny in the next post, 'cause I nearly lost this whole post (luckily I put it on my clipboard) because the board rejected the attachment.

[Plutarck]

Hopefully this'll work:


EDIT: Bah, forgot all Apolyton images were broken. Hrmf. I'll just attach it in .zip format. Inside is a .jpg.

[Mark_Everson]

Hey Plutarck, thanks for the solid comments! I will admit that I hadn't thought all that much about what a trireme moving up an edge river would Look like. Or for that matter any relatively skinny river. Time for some graphics demos! You there Stian?

Now I see why Gary's head hurt's... Or maybe it was that trip to the pub last nite

I need to soak some on the details of your suggestion, and the overall issues. So I'll just make a few comments on the side for now. I couldn't get anything out of the attachment. When I downloaded it, it was a file named "attachment" with no .zip or .jpg on it. Adding them by hand didn't work, so I've given up for now.

Originally posted by Plutarck
But the river would be considered too "small" for significant levels of cargo, so at most a small "trade" bonus could be given to each city for the river connection, but that's about all. And tiles that border the river will get a trade bonus (in the Civ3 style of Food, Production, and Commerce, all tiles bordering a river get +1 commerce regardless of terrain type).

Frankly if all the edge rivers do is speed individual movement, I would give them a miss entirely. That feature is not sufficiently important in the overall scheme of things to be worth the hassle IMO. Now if they had the border/defense-bonus aspects, and also could be sufficiently large for the merchant boats to use (no graphics there) then we're back to something that might be worth it.

Thanks for the detailed analysis! I'm looking forward to seeing what others have to say about it.

Cya,

Mark

[Plutarck]

The Apolyton attachments are definately ridin' my nerves. Try using this link for the screenshot (my LWC thread at civfanatics...hehe): http://forums.civfanatics.com/showth...120#post166342

If the attachments worked properly I'd post the actual tiles Civ3 uses to "overlay" rivers so you can see how they handle it, but I'll just leave it at that for now.



Oh, and on merchants: Since they aren't displayed then there'd be no problem having them use the rivers too. Anything that doesn't have it's own visible position on the map can use the rivers without problem. It's only when things need to be displayed (or perhaps even have their position recorded in coordinates) that things go awry.

So edge-rivers could be used for:

Defensive bonuses, borders, transportation of things which are not displayed graphically (communication, trade, supplys), economic/resource boosts to neighboring tiles, slowing down/preventing movement, and can be "bridged" allowing roads to pass right through them.

[Gary Thomas]

Deep and protracted thought about why I wanted ships sitting on rivers (we ignore River Queen) produced only HMS Amethyst. So I guess, indeed I hope, we can forgo warships on rivers.

As far as military operations were concerned, I can only think of rivers being used as a supply route. Again, a unit on the river is not needed.

Oh joy!

I had expected canals to be in square. However there are two kinds of canal - the commercial canals of yesteryear, and the military canals, mainly Kiel, Suez and Panama. They could be treated differently.

Cheers

[Mark_Everson]

Well, I also wanted Vikings to be able to get across Europe on their ships. But compared to adding a lot more complexity to rivers it doesn't seem that important. Also those moved in relatively small groups, a ship or a hadful at a time, not near the size of a unit in Clash. One wrinkle is that we could allow merchants to transport units as cargo. The cargo would be quiescent until getting to its destination. Kinda like a low-tech Airport, the unit goes in here, disappears, and re-appears some turns later wherever its supposed to go. Could even handle the Vikings that way. Not a big issue for now though!

So I'm pretty much with Gary on just preventing ship and TF icons from traveling On rivers. The supply aid that rivers provide in harsh territory will still be an important feature.

Thanks Plutarck for pushing us to think a bit further.

On canals. For the the commercial ones, I think they should be shown on-edge as straight rivers, and just function exactly as rivers do per our current spec. Only for Panama and Suez-type canals should they be in square center, and perhaps look somewhat as Plutarck had the Big in-square rivers. Although obviously some graphical demos will get us further than speculating.

[Gary Thomas]

I took railways and canals out of the code. Remember how I don't like coding for futures?

Cheers