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

[Ralf S. <rap...@ra...>]

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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