[Ashon]

We've been having a discussion about how we want to code our weather system for our project.  And we've got some great ideas (reposted here) but i was wondering how everyone else was doing their weather systems?  are they just the normal blah ideas, or are they something unique and special?

[b][u]The WM weather Engine:[u][b]
Each room has a terrain type, and x-y-z coordinates, from these we determine a couple of facts, first off the organic density, which is based on the terrain type, the y coordinate (latitude) and the z coordinate (altitude).

Then we find the water content, by using a LOS type of algorithm we find all the available water sources around.  This is used for the evaporation/condensation part of the weather.

Mix in the Jet stream map which overlays the world map, and now we have movement to our weather system.

In the next step we meld everything onto the day-night/time/temp sine-wave and adjust for the season, and the weather is taking care of.  The system calculates the humidity, the cloud conditions the tempature, the relative tempature, wind and so forth, and creates room objects for each room that takes care of all the effects.


what do you guys do?

[ScourgeX]

Wow, that sounds really advanced!
My only short-medium term plans are to make adjustments based on the terrian of the room (ie. if it's raining and the room is snow covered then change the weather to snow, if it's snowing and the room is in the desert, change it to rain). Long term I'd like to have different weather for different continents. Perhaps I'll make more advanced changes based on the ideas posted here

[Kallian]

For weather movement, a stat for barometric pressure is given to each room and then averaged into the region's pressure.

Storms are objects (a non sentient npc that can grow, shrink, and occupy many rooms simultaneously, actually) that move and flow according to surrounding pressures.

Humidity is on my to-do list.

[mhc]

We simply ignore any global weather, and let the different areas do their own thing.

[Ashon]

Originally Posted by (mhc @ Sep. 03 2002,08:11 am) We simply ignore any global weather, and let the different areas do their own thing.

Why? There's no consistency then. While I can understand that some areas should always have a dark cloud around them, or should always be raining for mood and whatnot, why shouldn't there be a global weather system?

[Dre]

Heya all,

Of course a global weather system is cool, but mostly an area determines a different place with all their own weather, in a desert it won't rain fast and so why not just put it in their own system?

Maybe it's easier to just relate some zones into one system, so two forest next to each other will have some kind of weathersystem, but the desert that lies to the south of it will have it desert specific weathersystem.

Although I must say, that Ashon's weather system sounds really neat. Although I wonder what you will do when you add an area, you have to change the whole map everytime, including the jetstream etc?

Greetings Dre

[Ashon]

See, that is part of the problem Dre, is that areas need to be done logisitically. Forest do not exist under any circumstances next to a forest. There is area inbetween the forest and the desert.

A global weather system takes intelligent design issues to deal with. You have to design the world before you can build the world. Just like you have to design the area before you build it.

But regardless in response to how my own projects system handles it: New areas are created dynamically. The world engine creates new parts of the world. An island may appear off the coast, or an ancient tower may appear in a forest. I like to call this undiscovered country. Players may have travelled an area, but that doesn't mean they've discovered the entire area.

This system incorporates the adjustments to the jetstreams, and since it is just a algorithmic function f(x) to draw the jetstream on top of the exisiting map, but adding a new location (x,y) the function simply adjust the jetstream slightly.

The main problem with this would probably be system resources. Calculating jetstream patterns, rainfall patterns, temperatures, relative temperatures, cloud cover, wind speed, wind direction, ammount of sunshine, fogginess, etc, for EVERY room in the MU* simply can NOT be very resource-friendly, especially if you consider it also has to run the rest of the MU* with it. For a frame of reference, modern day weather-forecasting supercomputers have 320 GB of RAM.

[Ike]

It is very impressive that you have calculated such a complex system. However, I am a fan of just allowing each area to have it's own weather system.

- I do enjoy noticeable weather in games though. On most muds I play, when "lightning crashes in the sky" I could frankly care less. I prefer for "lightning to crash briefly illuminating the objects around me".

[Ashon]

Originally Posted by (Ingham @ Sep. 10 2002,2:32 pm) The main problem with this would probably be system resources. Calculating jetstream patterns, rainfall patterns, temperatures, relative temperatures, cloud cover, wind speed, wind direction, ammount of sunshine, fogginess, etc, for EVERY room in the MU* simply can NOT be very resource-friendly, especially if you consider it also has to run the rest of the MU* with it. For a frame of reference, modern day weather-forecasting supercomputers have 320 GB of RAM.

It's no more complicated then most systems on a mud, and not as big of a resource hog as people would like to think.

Imagine the weather being as a group of mobile's. It moves from room to room. Either picking a flower or whatever, the mobile needs to know the room, what is around the room etc. The weather object needs to know the conditions of the room, and simply affect the room like a mob would. It then sends an update to the global system letting it know what happened. If two weather objects meet, then the weather could change drastically, which is where the memory footprint would come in, but it wouldn't be a lasting transition.

This of course is an overly-simplified run-down of how the system works. But it illustrates how non-intensive the system is.

[Kallian]

A complex weather system is vital for a realisic and advanced game. Those of you who don't really see the point probably just aren't thinking in the same scope as we are

Weather is neat not just because it enhances the "feel" of the mud ("The desert winds that blow through add a nice flavor to the desert", "The torrential rains in the swampland give it a more realistic feel"), but also because weather is part of the world.

I look at weather code for its functional aspects: Makes it really easy to code weather-affecting spells, creates more variety in the weather (flashfloods! drought! nice summer day! than I could manually, with much less effort.

Now if you just want weather for flavor or decoration, you don't need a complex weather system. But if your mud is like mine and bread does not mysteriously show up for sale in shops, but rather is delivered by the baker, who takes a delivery of flour from the mill, who takes a delivery of grain from the farmer, who actually plants and grows his wheat....

Well, have you ever seen a mud where a druid using lots of weather spells inadvertently crippled the supply of bread next season? No, you haven't.

There are countless other examples of cool cause and effect things that are not possible without a complex global weather system. Try to think of a few!

[Shao_Long]

well, if you'll have a mobile which is constantly moving in every room, it surely would ate a lot of resources, I think...

[Artovil]

Originally Posted by (Shao_Long @ Sep. 15 2002,08:30 am) well, if you'll have a mobile which is constantly moving in every room, it surely would ate a lot of resources, I think...

Actually, it will not eat resources by just moving about. If that was the case a normal player would eat as much resources, since they are, at least in DIKU/CircleMUD's, the same object type. So just having it/or a whole system of them moving is not a problem at all. What would take time are all the calculations for the weather, which mob to move where, and what it should look like, and so forth and so on, which has already been covered, yadda yadda. My finger actually hovered over the flame button there for a while. You have to be trolling, Shao. Nobody can... *mutes himself*

[OnyxFlame]

Ashon: in your world, can weather conditions change an area of plains into a desert, for instance? I think that'd be neat. Maybe even put in a little continental drift (although that would hardly ever be noticed) or earthquakes that could change the geography. What if a wizard cast a minor earthquake spell that caused instability and soon an earthquake much bigger than anyone could magically create happened? What if that prosperous port town was suddenly landlocked from it? What if another town (and all its inhabitants) suddenly ended up at the bottom of the ocean? What if the desert settlement that's been paying mages megabucks to give them rain suddenly becomes more fertile and here's a bunch of weather mages out of work? What if a long-dormant volcano erupts and the large clouds of ash decrease the yield of fields in the area, causing a food shortage? What if a river floods and washes away all the bridges over it, and the water is too turbulent for anyone to swim across or maneuver a boat on? And what of turbulent air's affects on dragons, birds, or flying vehicles players may use?

Lots of interesting possibilities for weather and spells that affect nature. *wanders off to cast a wither spell on an enemy castle's fields*

[Ashon]

Not yet, but that is the plan. We just haven't figured a system to change the terrain type based on long-term weather affects, seeing as the weather is based on the terrain.

[John]

Wow, that would be complex. I think you'd find that the terrain wasn't changed too often except because of Sapient interaction. Although if you have magic, it would be amazing to play a mud where if fire spells keep getting cast then it has a chance to turn into a desert, which would then cause havoc on the other areas around it, and it would be fun if the entire ecology was nearly destroyed cause of it.

That would be a case of your system is TOO realistic, and some Imm intervention would have to take place in the form of the local temple/kingdom taking action.

Just a question, what's the URL to your mud? I'm intrigued by it now.

[Ashon]

The problem that I see with the changing of the terrain are the constraints that we've decided on to make the system easier to code. First off, the terrain, and organic density are the biggest parts of the equation. Here are my thoughts so far on a system to actually change the terrain: As the weather changes it affects the following components: Organic Density and Tempature.

Seeing as how we just have a skeleton system right now and Organic Density is just a number, I imagine that it would be modified by tempature, becoming more/less depending on the increase/decrease of temp. Which in turn would affect the tempature more...

I suppose that I need to put more thought into what Organic Density means, and should be affected by...

muh... we are still in development and no-where near completion... but if you are interested, you should check my profile for appropriate links and whatnot...