How Many Terrain Textures Per Sim?

Does anyone know if there is a fixed number of terrain textures (i.e. vertical layers) per sim? Perhaps someone with an estate could tell me, since estates can change the textures? I thought I remembered a mention of 4 textures, but I can't find anything in the wiki, in the documentation of sim RAW files, or on the web. I've been working on a new database and code library for grid info. Currently I've got it structured to allow an abritrary number of terrain textures, but I would like to change it if it's a fixed number. So I'd appreciate it if anyone could help me out.

Go to World->Region/Estate. Go to the texture tab. I think you can see the menu itself without it being filled in if you don't own it.

Otherwise, you can set 4 textures vertically layered and you can define the layer hights in each corner of the sim, so you can have some difference even if it si the same height.

Hope that helped

Yes, four layers.

If you want, look me up and I can show you estate access for a few minutes in Caledon - it would be highly informative to see the controls, if you haven't.

There are 4 high-res and 4 low-res textures per sim. They have a very funky way of assigning and blending these 4 textures based on land high. I have yet to figure out when the low-res are used instead of the high-res... I think I have only seen the high-res.

You can see these textures for any sim by going World > Region/Estate > Texture

-Ghoti

Clients with low video memory will see the low res (I think it's 64mb or lower) and not the high.

Oh! That explains that! I've only ever had 128mb or 256mb videocards while using SL.

Thanks Adam.

-Ghoti

Great, thanks for all the info, folks! Desmond, I will probably take you up on that offer, I appreciate it. I'll also look at the Region/Estate menu on my own. A long time ago, it seemed to me that the black sand sims (around Mahulu I think) might be applying the textures partially based on slope. Did I imagine that?

4 pairs of textures (high and low rez) for four designated altitude layers, and you can skew the distribution of those layers by adjusting the altitude bands at each corner of the sim. So, for example, an island could have white sandy beaches on one coastline, and green grassy shores on another, by lowering the altitude at which the grassy band above the white sand appears on one or more corners. It's strictly altitude based - not slope.

The low-rez terrain texture also appears if that option is selected in a user's prefs. People with low-end video cards sometimes turn off rendering of high-res terrain textures to improve performance. If you're indoors, who cares what the ground outside looks like?

No, that's exactly correct - but there is also an algorithm that rather 'randomises' the blending so the textures aren't pure gradients.


Other than that the control goes somewhat like this:

NW corner | NE corner | SE corner | SW corner

low alt # | low alt # | low alt # | low alt #

high alt # | high alt # | high alt # | high alt #

(apply)


So say in the NW corner it was 10m for low, 40m for high altitude texture.

That means that the low texture would dominate at 10m altitude & below, the lower mid at 20m, the upper mid at 30m and the highest at 40m & up.

I'm on kinda randomly but fairly easy to find ^^

Thanks for the detailed responses I attached a screenshot of the textures dialog for Seacliff. I can see why I didn't realize there was this additional corner effect; the first sim texture set had the same setting at every corner, so the layers are actually horizontal (with randomized blending at the boundaries). I checked Kissling and it has the same values. I admit I'm still not completely clear about how the blending works, but I need to study it a bit. For instance, it looks like minimum and maximum heights are set only for the first and last texture. But how does it decide how to blend the two middle textures? Does it set the boundary by splitting the difference? Like I said, I need to study it some more. Thanks for all the help. Once I understand it better, I'll probably add this info to the wiki, if no one else has.

For anyone else curious about this stuff... It does seem like in the simple case the boundary between the second and third textures is the middle of the low and high values. For Seacliff, the low is 20 and the high is 60 for every corner. The boundaries do appear to be 20, 40, 60 based on observation. I guess I'll have come up with a function that generates vertical texture boundaries based on proximity to the corners...

It's a rather complex function, actually.

I've terraformed sims perfectly flat and set the heightmap flat, and what you get are spots and splotches of the textures above and below your land's present altitude.

I can't say I recognised the blending function. It appears to be a rather randomish thing; or maybe a 10th order or more polynomial mapping where z = f(x,y). Whatever the function is, it appears to be 'seamless' to adjoining sims.

I won't be terraforming a sim again until early September; perhaps catch someone with a brand new island (or me in September) and you can take a series of detailed overhead screenshots with a defined solid-color topographic texture grid.

I'd love to know what the texture mapping function is myself.