Player light problem

jimbo · Post by **jimbo** » Thu Aug 09, 2007 22:51

Hi there,

I'm mainly using GZDoom to play the 'ol doom games with sexier graphics but I noticed somthing's slighty amiss. The player in the Doom games seems to emit his own light that brightens walls / creatures in dark rooms as you get closer to them - but this doesn't happen with GZDoom (though swtiching the render to software or just using ZDoom does... but looks crap:)

Is it something I'm doing wrong or have missed?

I've tested this on my desktop & laptop - both use Radeon cards (desktop gfx card is a Radeon X800.) I'm using the latest versions of ZDoom & GZDoom on WinXP.

Thanks

YouTube · Post by **Nash** » Thu Aug 09, 2007 23:28

The effect you are talking about is the software renderer's "Doom fog" as most people call it.

The Doom fog is not easily achievable using the OpenGL renderer. Graf Zahl may have more technical information but all I can tell you right now that if it could have been done easily, it would have been done a long time ago.

The lack of the Doom fog also leads to some bland-looking lighting in maps when using OpenGL. It's not a big issue really but yes it does make it not look like the Doom you are used to seeing.

Currently the only port I'm aware of that emulates Doom fog in OpenGL correctly is EDGE.

I'm sure Graf would like to implement it eventually though.

Lazureus · Post by **Lazureus** » Fri Aug 10, 2007 2:33

There IS some fog in GZ's opengl, it's just faint and not very customizable. There's about 5 settings for it and none of them use as severe fog as software renderer. Putting sector light level on "standard" is closest, though.

Post by **Graf Zahl** » Fri Aug 10, 2007 9:12

Unfortunately the hardware based fog is not customizable enough. And using shaders for this causes too many problems with the renderer. It just was never designed for shaders.

YouTube · Post by **Nash** » Fri Aug 10, 2007 9:19

Graf, how does EDGE pull it off? Is it using some hardware features that older graphics cards can't do?

Post by **Graf Zahl** » Fri Aug 10, 2007 15:22

No. It splits polygons across fog density boundaries.

jimbo · Post by **jimbo** » Fri Aug 10, 2007 15:37

Thanks for the replies & info guys. Using the sector light level at standard does brighten up some of the darker parts so that'll do.

YouTube · Post by **Nash** » Fri Aug 10, 2007 23:59

Graf Zahl wrote:No. It splits polygons across fog density boundaries.

Is this something that can be done with your renderer?

Post by **Graf Zahl** » Sat Aug 11, 2007 0:37

It's something that can be really, really messy. I'd rather not bother with it and its implications.