Lighting on textures doesn't fade gracefully..

Lighting on textures doesn't fade gracefully..

Re: Lighting on textures doesn't fade gracefully.. Posted by Warren on Sat Nov 4th 2006 at 7:08am
Warren
17 posts
Posted 2006-11-04 7:08am
Warren
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17 posts 2 snarkmarks Registered: Aug 7th 2006
Some images in this post have been automatically down-sized, click on them to view the full sized versions:

Some images in this post have been automatically down-sized, click on them to view the full sized versions:

A minor issue with lighting. I have a large, moderately complex room
lit by a variety of low intensity spotlights. The problem I'm having is
that textures that are hit by very dim light towards the point where
light becomes negligable, become discolored and "blotchy."

You can observe the same thing often in games like Deus Ex, although it
might depend on monitor and ingame brightness settings. (I wonder)
Here's a couple screenshots of one of the more noticeable instances:

The top screenshot here is unaltered and in the bottom one I boosted
the brightness and contrast in Photoshop to illustrate the problem.
Where you can see it go blue in the bottom shot is where the problem
lies.

User posted image

User posted image

I hope the problem is visible in the top shot - it's hard for me to
even see a problem myself, but in-game it was very noticeable.

The light fading degradation if I may call it that was more severe
before I changed the lightmap scale on all the room's textures to 4,
which is what they are set at in these shots.

Is there anything else I can do? Or, is this related to an unusually
high brightness setting within HL2 or from my monitor? (That means for
other people it should look fine)
Re: Lighting on textures doesn't fade gracefully.. Posted by fishy on Sat Nov 4th 2006 at 11:30am
fishy
2623 posts
Posted 2006-11-04 11:30am
fishy
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2623 posts 1476 snarkmarks Registered: Sep 7th 2003 Location: glasgow
the top picture is almost black for me, although the bottom-right corner of it seems to have a little bit of light that evenly fades out to black.
i eat paint
Re: Lighting on textures doesn't fade gracefully.. Posted by Orpheus on Sat Nov 4th 2006 at 1:29pm
Orpheus
13860 posts
Posted 2006-11-04 1:29pm
Orpheus
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13860 posts 2024 snarkmarks Registered: Aug 26th 2001 Occupation: Long Haul Trucking Location: Long Oklahoma - USA
I can see both.. IMO you're a bit premature in your concern. The room/area consists of vacant wall textures. /methinks that once the compiler tools have a bit of useful detail to work with that the light issue will play itself out.

/opinion

The best things in life, aren't things.
Re: Lighting on textures doesn't fade gracefully.. Posted by Dark_Kilauea on Sat Nov 4th 2006 at 7:30pm
Dark_Kilauea
629 posts
Posted 2006-11-04 7:30pm
629 posts 123 snarkmarks Registered: Apr 15th 2005 Occupation: Fast Food Location: USA
Yes, this is an artifact caused by not enough light on certain textures. You can reduce the effect somewhat by decreasing the light scale. Another technique is to use so called "black lights." Make several lights of low intensity that have a color value of 0,0,0. Cubemaps do not help though.

Usually, this artifact is not a problem due to the final texture being diverse enough that the effect is never noticeable.
Dark_Kilauea
DVS Administration
http://www.dvstudio-production.com/
Re: Lighting on textures doesn't fade gracefully.. Posted by reaper47 on Sun Nov 5th 2006 at 1:19pm
reaper47
2827 posts
Posted 2006-11-05 1:19pm
reaper47
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2827 posts 1921 snarkmarks Registered: Feb 16th 2005 Location: Austria
These effects are almost impossible to avoid. You'll find some dark, ugly spots in professional maps as well. It's RAD not calculating light bounces correctly (every wall reflects a tiny amount of lighting and bounces it around to make shadow areas not so pitch-black [Doom3]).

Adding more or brighter lights might work, but it will also kill the nice contrast between dark and shady spots.

A VRAD compile with "-final" (which takes about 3 times as long) also adds a bit of quality. But the artifacts won't be gone completely.

If you work on your brush-architecture and texturing no-one will blame you for this, probably even won't notice it at all. Be happy with it.

PS: Dark_Kilauea: Black lights? Never heared of that! Interesting! Do they make the room darker?
Why snark works.
Re: Lighting on textures doesn't fade gracefully.. Posted by Dark_Kilauea on Sun Nov 5th 2006 at 5:59pm
Dark_Kilauea
629 posts
Posted 2006-11-05 5:59pm
629 posts 123 snarkmarks Registered: Apr 15th 2005 Occupation: Fast Food Location: USA
I have yet to use them myself, but apparently, yes they do paint an area darker, but don't use them with high intensities :smile:
Dark_Kilauea
DVS Administration
http://www.dvstudio-production.com/
Re: Lighting on textures doesn't fade gracefully.. Posted by midkay on Sun Nov 5th 2006 at 8:17pm
midkay
398 posts
Posted 2006-11-05 8:17pm
midkay
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398 posts 120 snarkmarks Registered: Apr 15th 2005 Location: United States
Just curious - have you got a leak in your map?

I used to have this on one of my maps in a dark room - it was terrible. There was this red and blue weird blotchiness on the walls. I realized I had a leak, fixed it, recompiled and the entire map was much more evenly-lit (vrad calculating radiosity) and as a result of radiosity, the blotches were gone.
-- midkay
Re: Lighting on textures doesn't fade gracefully.. Posted by Orpheus on Sun Nov 5th 2006 at 8:24pm
Orpheus
13860 posts
Posted 2006-11-05 8:24pm
Orpheus
member
13860 posts 2024 snarkmarks Registered: Aug 26th 2001 Occupation: Long Haul Trucking Location: Long Oklahoma - USA
whispers

Wouldn't it be fullbright and hence no shadows at all?

The best things in life, aren't things.
Re: Lighting on textures doesn't fade gracefully.. Posted by midkay on Sun Nov 5th 2006 at 8:37pm
midkay
398 posts
Posted 2006-11-05 8:37pm
midkay
member
398 posts 120 snarkmarks Registered: Apr 15th 2005 Location: United States
whispers back

Not at all. Vrad still runs when you have a leak, just "not as well" (doesn't do the whole radiosity bit that takes all of about 2 seconds).
-- midkay
Re: Lighting on textures doesn't fade gracefully.. Posted by Orpheus on Sun Nov 5th 2006 at 8:54pm
Orpheus
13860 posts
Posted 2006-11-05 8:54pm
Orpheus
member
13860 posts 2024 snarkmarks Registered: Aug 26th 2001 Occupation: Long Haul Trucking Location: Long Oklahoma - USA
Whispers, inhales spittle and coughs uncontrollably

glares at midkay for causing scene

I wouldn't know really. I don't create leaks. Have not actually had one since my second or third release.

The best things in life, aren't things.
Re: Lighting on textures doesn't fade gracefully.. Posted by Warren on Sun Nov 5th 2006 at 10:06pm
Warren
17 posts
Posted 2006-11-05 10:06pm
Warren
member
17 posts 2 snarkmarks Registered: Aug 7th 2006
Orpheus: the area is almost fully textured. I've used a placeholder
texture in the above screenshots because I'm about to build a door and
hallway through it. But there's similar artifacts on even the detailed
textures.

Dark_Kilauea: I will give that a try.

midkay: no leaks. :smile:

Thank you for the help gentlemen.

[b][url]users.php?name=Dark_Kilauea[/b][/url]
Re: Lighting on textures doesn't fade gracefully.. Posted by midkay on Sun Nov 5th 2006 at 10:10pm
midkay
398 posts
Posted 2006-11-05 10:10pm
midkay
member
398 posts 120 snarkmarks Registered: Apr 15th 2005 Location: United States
whispers back at Orph

Ah, fine excuse, fine excuse indeed.
-- midkay