Hmmm - well, it's possible to set things up so that water recieves light but doesn't occlude it - which actually looks mostly OK!

http://i.imgur.com/lDKcJs7.jpg 

Warren speaks the truth. Let's not get sperged down by details of physically realistic water.

I reckon:

ability to specify lightmap resolution on liquids - as discussed, lower resolutions than usual will probably look better.

0-1 float value to define liquid lightmap "influence" - 0 = fullbright surface as before, 1 = full lightmap, as if it's a solid opaque surface.

For lava, I'm sure you'd want 0 always, but for slime and water, I reckon there's a happy medium somwhere. 

 

And then normalize the color maybe?
Just thinking out loud here...

float Alpha = magnitude(lightmap.rgb)
float3 LightColor = normalize(lightmap.rgb)
float3 Color = texture.rgb * LightColor
output float4(Color, Alpha)

Haven't written any shaders in years, can't remember how it's actually done.

Maybe skip the color and just use intensity
Maybe this would look completely weird... 

the reason why we dont have lightmapping on water was because the water texture warps around and moves, and the lightmap would move and distort with it? 

Not necessarily. It's possible to warp the water texture but not warp the lightmap. 

I do hope this is something that gets implemented then, fullbright water is crap. 

Is gorgeous, lets just do that ;)

Theres no clean water in quake anyway! Shub-n-word-erath and his buddies have been jizzing in it for aeons, we all know that. Does no one even read the back story? 

https://www.shadertoy.com/view/MtB3DK
Click and drag around to mess with the alpha values! I'm sorry I suck at this! 

I'm not quite sure I see the appeal of what's going on in that czg...thing - but let's stick with the czg theme for a bit and just remind ourselves about this sort of thing:

http://i.imgur.com/htecdQb.jpg

We've been using those crummy "waterfall" textures for years, and they get lightmapped, and I don't think anyone's complained (about the lightmaps on them). I think they look alright don't they? I still don't get what's so terrible about just trying that on the proper liquids. 

Well... that's something we can test right now with the tools given to us. Here's a crummy waterfall made of func_illusionarys with "alpha" "0.65"

http://scampie.net/etc/transwater_1.jpg
http://scampie.net/etc/transwater_2.jpg

It looks okish when viewed from above, but once you get to about chest deep in the water, you realize it's just a plane of animated texture and it starts to look fake. It's not the worst thing in the world, but certainly not convincing.

here's the .bsp and .map and all that. requires an engine that supports "alpha" key on brush models (fitzquake engines)... if you want to compile the .map so you can fool with the alpha values and such, you'll want ericw's tyrlite becuase it's mostly lit with sunlight and sunlight2
http://scampie.net/etc/transwatertest.zip 

"It's not the worst thing in the world, but certainly not convincing. "

This implies that it was convincing before. 

Well, what I meant is it looks odder where you have a lightmap on the transparent water because you lose a sense of it having any volume. The bright spots on the surface of the water call attention to the fact that there should be lighting on some volume inside the water as well, so it ends up just looking like a flat plane suspended in the air. In a modern engine, people would be putting volumetric effects and fog in the water to hide exactly this.

http://scampie.net/etc/transwater_3.jpg
Uniform brightness of the water surface, despite being too bright here, seems to sell volume better. Without the added transparency of the shadowed areas revealing that the light isn't hitting any particles in the water, your mind fills in that the water must be dense. I think if this were simply vertex lit to end up being closer to average brightness of the area it would look fine. 

I for one love it. And just leave it up to the math authors to support it or not. This on muddy swamp water would look great. This could work nicely when used on fake ground fog as well. 

Just started with corridor for the level introduction. I'm not even sure if that matches the theme in anyway, also I wasn't using any level editor for like 7 years, so it is just a quick sketch to remember basic things:

http://imgur.com/a/rGJIz 

Quick fix for geometry, small changes for light and texturing:

http://imgur.com/8GSFG88 

I think you're in the wrong thread. :)