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White Knight
09-14-2004, 05:45 AM
How do I make my skydome produce darker shadows?
The skydome washes out all shadows so they get too weak.

/White Knight

BeeVee
09-14-2004, 07:34 AM
If you are producing FP images in LightWave, you can use Image ViewerFP's Expose functions to adjust the colour range that you image has.

B

cathuria
09-14-2004, 07:45 AM
Light domes generally provide even illumination from all sides. You can adjust this by either "lighting" your dome with a gradient (luminosity on slope, so that the topmost part of the dome is much brighter than the sides), or by dividing the dome's poly's into bands and giving the lower bands less luminosity than the top of the dome.
You will still get soft shadows, but the more defined light direction will create more contrast.

You might also ask if you really want skydome lighting if you're looking for dark shadows. Perhaps just a spotlight with radiosity?

wacom
09-14-2004, 09:44 AM
You could also try this:

http://www.informatik.hu-berlin.de/~goetsch/AmbOcc/

And no, just because I keep recomending it like a door to door sales man doesn't mean I'm selling it! :)

Give it a try...

mattclary
09-14-2004, 01:52 PM
Wacom, you sound like me with F-Prime latey! I'm a Worley wh*re. :cool:

wacom
09-14-2004, 02:33 PM
Hey- don't even get me started on FPrime! That program makes my day- day after day.

The catch is that many didn't buy it when it was just 279- which was a great deal IMHO. This Ambi-Occu shader however is free (for now at least) so I think it's worth peoples time/money to try it out- so you bet where ever a GI related topic pops up my ugly mug is going to pop up with this too!

White Knight
09-15-2004, 01:29 AM
Thanx all you guys for all the hints! Apriciate it!

Cathuria: I've tried the gradient-thing but when I use 'Slope' the whole scene gets dark. Guess I must have missed some setting.
However it does work if I use 'Y-distance from object' but it only makes the scene in whole a bit darker and the effect on the shadows is unnoticable.

Wacom: Thanx. According to flay many people are jazzed up about that shader so I think I'll give it a try. =)

White Knight
09-15-2004, 02:11 AM
You could also try this:

http://www.informatik.hu-berlin.de/~goetsch/AmbOcc/

And no, just because I keep recomending it like a door to door sales man doesn't mean I'm selling it! :)

Give it a try...

How do I actually use this plug?
What's the process of setting it up and useing it with FPrime?

hrgiger
09-15-2004, 03:44 AM
The whole idea of a skydome is to simulate the lighting that you would get on a cloudy day without any strong directional light source so you really shouldn't be getting dark shadows at all. If you want stronger shadows, you'll have to give some indication of a directional light source that doesn't cover the whole sky.

What I have done generally in this case is made my light dome a lower intensity to make my ambient lighting. Say make most of the light dome around 20-25% luminous. But then I select some of the polys of my light dome in modeler on one side of it and make them a higher value of say 150-200% to simulate a directional lighting.

wacom
09-15-2004, 08:24 PM
How do I actually use this plug?
What's the process of setting it up and useing it with FPrime?

Doh! I didn't know you have FPrime! Well then...hmm. To be honest this plug will only help you out in FPrime if you want to use it to fake some of your GI. I'd say if you want to NOT use radiosity (BG or MC) in FPrime for everything and want to use area lights with inverse falloff or inverse falloff^2 then this plug-in is worth messing with to get the right look.

You can use it a couple of ways, but if you aren't moving the camera in your set I suggest you render out a copy from you camera view with the shader in "shader only" render mode. You should get a grey scale image. Then you apply this to the diffuse channel of your sets textures as a front projected image. It's not really a replacement for true radiosity, but it can be good for a faked GI BG radiosity look. Then if anything is moving in your set you can opt to have it lit with BG radiosity/radiosity so you only have to render out Radiosity for the moving objects. There are a lot of other options...but you get my drift.

Once we can bake things with FPrime though this would be a moot advantage (hell you can even do the front project thing with Fprime already).

Well that's the long way of saying it's just another option...

White Knight
09-17-2004, 12:52 AM
Whow, thanks a bunch guys!
Really nice hints from all of you.

In the what gavge me the most obvious results was when I used Cathuria's suggestion of simply "manually" assign surfaces with different luminosity to different "rows" of the polydome. In other words select the bottom few rows and give it a value of say 10% and the rows nearer to the top 25% and the topmost about 200%.
I tried different types of gradients (which should do the same things but smoother) but somehow they didn't make as clear results and I found it a bit harder to control the outcome.
Then again it's probably just some setting which would have needed to be tweaked to get that right too (was a bit in a hurry).


/White Knight.