Re: [Algorithms] Tangential Curvature of terrain

[Klaus H. <k_h...@os...>]

Pierre,

I think it's better if you look for yourself, because people tend to show
the nicest screenshot they can find, and so do I :)

(Win95/98/2K, 108 KB)
http://www.thecore.de/TheCore/gdhighlands.zip

Some instructions...

First run the program Highlands.exe. It'll then take a while before you see
some terrain, because the program needs to generate the height field and
textures.
If you have enough video memory, then try to maximize the window now,
because that looks better... after all you want to judge the quality of the
texture, and not of quality of the LOD algorithm. So it doesn't matter if
things run a bit slower.
Now press and hold the <4> key, until the status bar at the top reads "MRes:
15". Note, that the status bar will not update while you hold the key, so
just hold it long enough. Next step is to enable geomorphing by pressing the
<g> key once. Now you can walk around (press <h> for help).

Some more info...
[1] The sample is work-in-progress, so there are a couple of flaws. For
example, there are situations, where popping occurs, even though geomorphing
is enabled. Also, I don't free all memory, so don't use the <r> key too
much. In addition, the rendering code is slow (the OpenGL specific pieces).

[2] The terrain is 1025x1025, and the texture is 1024x1024 (divided into
sixteen 256x256 patches). Thus, there's less than 1 texel per data point.

[3] I didn't use any image files to create the surface texture. It is
color-based only. In fact there are seven different colors. 3 of these
colors are green, 2 are sand, and 2 are gray. The noise-like
ground-structure was done by adding a small random value to he illumination
factors.

[4] There are two light sources. The first one is a direct sun-light that
shines from the east, and the second is an anit-sunlight source that shines
from the west. The lighting is sort of bad, and that's why darker places
look much better than bright places.

[5] There's no additional noise used to break up the transitions between the
ecosystems. It's purely based on the height field.

[6] As I said... some places look good, which does not mean all places :) So
you'll have to walk a bit, and maybe try a couple of other terrain (see
help). Most of the time, things look good, if you are not too close to the
sight (there's no detail mapping or something like that).

Niki

----- Original Message -----
From: Pierre Terdiman <p.t...@wa...>
To: <gda...@li...>
Sent: Tuesday, August 22, 2000 4:29 PM
Subject: Re: [Algorithms] Tangential Curvature of terrain


> > There are places in my terrain that look almost real, and I could
further
> > enhance this by casting shadows.
>
> What about a new snapshot...?   :)
>
> Pierre
>
>
>
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