NEW CLIMATES MODEL (was: The Equatorial Wind)

Topic: NEW CLIMATES MODEL (was: The Equatorial Wind) (Read 36995 times) previous topic - next topic

Re: NEW CLIMATES MODEL (was: The Equatorial Wind)

Reply #70 – February 10, 2010, 07:19:24 pm

My original post was focused specifically on the climate model as opposed to the way tiles are rendered in a broader sense. I think the current rendering method does work fine; you can move around large maps with ease. The current climate model also works fine on its own terms; but if one is trying to create maps on a continental scale the ability to vary climate according to latitude (as well as height) would be a huge plus.

I would be interested in what people think to my idea above of having climate affected by a simple relationship between latitude (as represented by the y coordinate of a tile) and the climate type. In essence I'm saying: make the climate of a tile dependent on its y and z coordinates as opposed to just the z coordinate as at present. I think I'm right in saying that doing this would not require any expansion in the current tile set.

Re: NEW CLIMATES MODEL (was: The Equatorial Wind)

Reply #71 – February 10, 2010, 08:11:49 pm

There is some merit in what Andyh is saying - this idea was actually discussed further back in the thread, with the idea of an "equator offset". Unless I am missing something, it would be a simple and effective way to add considerably more realism to the game.

Re: NEW CLIMATES MODEL (was: The Equatorial Wind)

Reply #72 – February 10, 2010, 08:58:51 pm

Also the link above shows a very interesting system to generate climates; one that would be easily applicable to simutrans and might generate much nicer maps than now.

Re: NEW CLIMATES MODEL (was: The Equatorial Wind)

Reply #73 – February 10, 2010, 11:07:37 pm

The climate generation system shown in the link is based on the concept of moisture being blown across a relief map creating areas of relief rainfall (damp climates), and rain shadow (drier climates). It does not take latitude into account. This method would be very good for generating climates on a small-medium sized map; say one where the North-South dimension being modelled is no more than a few hundred kilometers. However, by itself, it would be less good on the continental scale where climate variation is more heavily influenced by latitude. To illustrate: differences in climate within Washington State can easily be explained by looking at moisture, wind patterns and topography (i.e. where the mountains are), but the difference in climate between Alberta and Louisiana has more to do with the fact that Alberta is a lot closer to the North Pole.

Ideally, of course we would include all these factors (i.e. latitude, elevation and wind/moisture) in a Simutrans climate model. I'm very new to the forum, although I've been playing Simutrans for years; how can I get involved so as to move this initiative forward? I have little to no programming skills, but I think that I could come up with some mathematical models, and perhaps provide some insights on the geographical side of things.

Re: NEW CLIMATES MODEL (was: The Equatorial Wind)

Reply #74 – February 10, 2010, 11:16:14 pm

One other thing that would have to be considered is the scale of the map.

Re: NEW CLIMATES MODEL (was: The Equatorial Wind)

Reply #75 – February 11, 2010, 09:21:28 am

@Andyh:
Unfourtunately ideas are not lacking; programming time on the other hand is.

Re: NEW CLIMATES MODEL (was: The Equatorial Wind)

Reply #76 – February 11, 2010, 01:18:50 pm

Quote from: Andyh – on February 10, 2010, 11:07:37 pm

Ideally, of course we would include all these factors (i.e. latitude, elevation and wind/moisture) in a Simutrans climate model. I'm very new to the forum, although I've been playing Simutrans for years; how can I get involved so as to move this initiative forward? I have little to no programming skills, but I think that I could come up with some mathematical models, and perhaps provide some insights on the geographical side of things.

Then you need to find someone who shares your interest in these ideas and who can program them for you. Currently there are about three people actively coding for Simutrans, and they are all busy with other tasks, i think.

As Prissi said, ideas are plenty around Simutrans, but there are only few people who (can) do the work.

Re: NEW CLIMATES MODEL (was: The Equatorial Wind)

Reply #77 – February 12, 2010, 05:21:12 pm

Any changes to the current model would require more tiles. The computer generated maps in the link do look nice. However I think technically it will be too tricky to implement. If you are going that far you might as well put a simple weather system in so that areas would get snow on and off through the winter, maybe have images for it raining and snowing, variable amounts of snow on the ground. It would all be great eye candy but really not much more than that.

Re: NEW CLIMATES MODEL (was: The Equatorial Wind)

Reply #78 – February 12, 2010, 06:25:24 pm

Quote from: kierongreen – on February 12, 2010, 05:21:12 pm

Any changes to the current model would require more tiles.

I don't think that this is necessarily the case. As explained in my original post, unless I'm missing something I don't believe that a simple latitude-based climate modification of the type I describe WOULD require more tiles (because it uses the same climates and the same climate sequence as at present).

Here's what I would suggest: I've downloaded the Simutrans source code. Would someone mind giving me a few general hints as to how to go about building a little mod? Specifically: which files/lines contain the code which defines the climate ****ociated with a tile? I'll then noodle around a bit myself and see whether I can come up with something.

Thanks a lot for everyone's help and advice

Re: NEW CLIMATES MODEL (was: The Equatorial Wind)

Reply #79 – February 12, 2010, 08:30:49 pm

THis is simple:

The climate is given by simworld::get_climate, found in simworld.h line 609 or so.

Code: [Select]

	/**
	* returns the current climate for a given height
	* uses as private lookup table for speed
	* @author prissi
	*/
	climate get_climate(sint16 height) const
	{
		const sint16 h=(height-grundw****er)/Z_TILE_STEP;
		if(h<0) {
			return water_climate;
		} else if(h>=32) {
			return arctic_climate;
		}
		return (climate)height_to_climate[h];
	}

Unfourtunately for non-height dependent climate, you need to change all calls to this function (And probably make climate instead a property of the ground).

Re: NEW CLIMATES MODEL (was: The Equatorial Wind)

Reply #80 – February 13, 2010, 08:48:31 am

Even a latitude based offset to climate would require more tiles. Admittedly not as many as some other systems but still 4 * 7 * 2 potentially taking into account all the climate transitions and snow. Another problem is that the new map configuration window would become more confusing as you would have to set several latitude options.

Re: NEW CLIMATES MODEL (was: The Equatorial Wind)

Reply #81 – February 13, 2010, 01:03:58 pm

Quote from: kierongreen – on February 13, 2010, 08:48:31 am

Another problem is that the new map configuration window would become more confusing as you would have to set several latitude options.

If the UI is made clear, it would not add much in the way of confusion. Additional options in the "climates" window would be a price very much worth paying for this improvement.