Raw Terrain Files

...while waiting for my island, I've been offline designing in the dark...The RAW file as an example is VERY helpful!

*MWAH*

I'm curious how many people actually use Terragen to create terrains for sims. The reason I'm interested is I've written a .NET app for editing sim raw files that imports and exports Terragen files, but doesn't currently do any terrain editing itself (it does edit the other channels). I've seen people suggest Terragen, but I realized I don't know how much it's actually used.

I've recently been using World Machine (http://www.world-machine.com) to generate a .768 sq. km terrain, which I then save as a TIF (or other image file, rather than the various RAW formats.)

Download the/a sample RAW file. There's one available through the knowledge base, or you can download the terrain for an island. In Photoshop CS2 I open it as a 256x256 13 channel RAW file.

Now open the terrain image from World Machine, select and copy the entire image to the clipboard. Replace the relevant channel* (channel #1) with your WM terrain. Fill channel 2 with a single shade of gray for ease of use. Save as a Photoshop RAW file in interleaved format.

Upload, rinse and repeat. You may also need or want to zero out channels 12 & 13, which appear to be the "original" height and multiplier fields.

As of Dec 12, 2006, the current terrain in the Lovelace sim is an example of WM work.

The chief problem, IMO, and confirmed with focus group testing, is that the scale is psychologically wonky, since it's a .768km2 space reduced to 256m2. The terrain looks amazing, but it also looks like a model. Mr. Desmond Shang suggesting switching to a tiny avatar, and that helped a lot. The solution will either be to tweak the vertical scale a bit or just carve out a small chunk of a larger generated section.

As mentioned elsewhere, detailed instructions are available at: http://secondlife.com/knowledgebase/article.php?id=288

I've attached the RAW file for Lovelace' current terrain.

*Please note that I said "channel" and not "layer".

CoyoteAngel,
Thanks for the pointer to World-Machine!
Its 'almost' enough to make me forego my Mac and go rent a PC to do terrain modeling!

I'm curious about your comment that "The terrain looks ... like a model... suggesting switching to a tiny avatar." You say to fill Channel 2 with a single shade of gray. Channel 2 is used as a 'multiplier' to the height in Channel 1. (and my experiments show its more of a geometric multiplier effect--doubling it seems to result in about a 4x difference between the mountain highs and the valley lows).

Have you tried filling channel 2 with a single shade of gray that's closer to black?
I'd be curious if that fixes the out of proportion terrain...

Another way to think about channel 2 is that it is the resolution. A value of 127 everywhere in channel 2 means that channel 1 values indicate 0 to 255 meters, in 1 m increments.

A value of 64 (or so) in channel 2 means that channel 1 values are

0 --> 0
255 --> 127m high

with a resolution of 1/2 meter.

A value of 32 means

0 --> 0
255 --> 63m high

with a resolution of 1/4 meter.

So, it seems like you would get the most precision if you choose channel 2 based on the highest altitude you want in SL.

May or may not help, but --

http://blogs.electricsheepcompany.com/primdig/?p=4

Good luck

The OOP problem is just that I'm shrinking terrain features to fit in 256x256, and it's not a good psychological fit. If you take a 1000 yard high mountain and shrink it to 10 yards, it's just gonna look weird, 'cause terrain is shaped based on materials and wear, which are scale dependent.

Halving my height just made everything look twice as large, or four times if you're a mathematician. Or something.

I tried the canonical greys: {0,0,0} {127,127,127}, {255,255,255} and a few random settings and sure enough, it multipled my terrain, however, see my first comment. Just shrinking major land features produces uncontrollable cognitive dissonance. Cranking down the fog distance helps a little, but mostly I just need to make terrain at the proper scale.

CoyoteAngel,
My comment was meant to suggest filling channel 2 with <35,35,35>, or <71,71,71> (both as examples). The idea to make the fill color closer to black <0,0,0>. This seems to relieve the 'startling' effect that channel 2 seems to have on height. It seems to be a geometric effect... (Lee Ponzu has some insight into this, as well. There's another thread running on this very issue.)

But, 'yes', the cognitive dissonance issues with the scale is troubling. I thought I had great islands designed, with beautiful mountains, until I plopped down some 10x10x10 cubes as sample buildings...and realized that a 60meter mountain looks all out of proportion. I'm back to playing with the RAW terrain files trying to get it right.

Not <35,35,35>. Channel 2 is the second number only. Depending on your tool, you would probably be ok. Painting in channel 2 would only *use* the second number. I'd hate to see you accidentally make all of channel 1 have a value of 35, too, though.

As described elsewhere, a value of 127 in channel 2 (everywhere) means that channel 1 represents 0 to 255 meters. You want startling? A value of 255 in channel 2 means that channel 1 represents 0 to 510 meters . WoooHooo.

One apprach is

Choose your maximum needed altitude, say H. Fill channel 2 with H/2 (rounded to integer). This will give you maximum resolution of height changes.