RE: [Algorithms] It looks terrible (was: Lightmap Terrain)

[Pallister, K. <kim...@in...>]

Niki,

Why are you anti-ambient lighting?

Everyone else, am I the only one that find's Ralf's email address
intriguing?

Kim Pallister

We will find a way or we will make one.
                     - Hannibal


> -----Original Message-----
> From: Ralf Schneider [mailto:rap...@ra...]
> Sent: Sunday, August 27, 2000 8:27 AM
> To: gda...@li...
> Subject: Re: [Algorithms] It looks terrible (was: Lightmap Terrain)
> 
> 
> Niki,
> 
> well it do NOT look that terrible!
> it's a lightmap, isn't it? what du you suspect?
> shadows make scenes nore realistic, not neccesarily 
> beautiful. you are loosing visual information if yo add 
> shadows to a top down view of a heightfield. you know that 
> already, because you are trying to avoid it, by using a 
> second light source instead of ambient light (we can say the 
> second light is simulating the reflection of the sun at the 
> other mountain...).
> 
> take a look at some landscape/mountain top-down photos. i 
> guess, you will recognice you lightmap is ok!
> 
> greetings, ralf
> 
> 
> | Hi all,
> 
> | Please have a look at the following image (~310 KB):
> | http://www.thecore.de/TheCore/shadows.jpg
> 
> | This lightmap looks majorly terrible, and I'm looking for 
> ways to enhance
> | this. I use the simple dot-product approach, and I have two 
> light source.
> | One light source (sun) is to the east, and the other 
> ('anti' sun) is to the
> | west. I use two light sources, because I don't like 
> ambient. I compute the
> | light for each texel, and then I cast a ray towards the sun 
> (directional
> | light). If this ray intersect with the surface before it 
> reaches the sun,
> | then I decrease the texel's intensity by some amount. I 
> don't reflect or
> | refract rays. I figured, that reflection probably wouldn't 
> make much sense,
> | because there's only a few cases where the reflected ray 
> would hit the
> | terrain again (or am I wrong?).
> 
> | How can I make this look better? For example, is there a 
> way to have real
> | penumbrae in the shadows. Of course, I could blur the 
> image, but that just
> | wouldn't be the same.
> 
> | Any ideas? Honestly... a simple dot-product (without 
> shadows) looks more
> | than twice as good (I can upload the same scene without shadows, if
> | requested).
> | Niki
> 
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