Forcing LMT to use it's own external lightmap?

(G0-Gerbil) #1

Erm, how?
I notice in fueldump etc the LMT uses it’s own lightmaps.
I want to simulate this because I’m doing some shading messing with my terrain shaders, and I need to manually edit the lightmaps for the terrain.
Currently of course it’s all just a big mess, and I can’t clearly see which bit is which, not to mention every time I recompile it changes :slight_smile:

(G0-Gerbil) #2

Might as well give you an idea of what I’m trying to achieve:

For my helm’s deep map I have terrain that obviously ends, but with no VIS blocking, IE you can see (and actually get quite close to) the edge of the terrain.

What I’m trying to do (and almost managing if it wasn’t for this problem of tracking down the lightmap pixels associated with the edges) is take the last row of terrain and fade it.

The idea is I use a unique terrain texture and paint it all along the one edge. Then I manually edit the shader that defines this boundary, and remove the top layer, and make the bottom layer fade using alpha gen.

This works fine, but of course I want lightmapped terrain, so…

I simply leave in the lightmap layer, and then manually fade this edge from whatever colours it is to uniform grey. So the faded bits ARE lightmapped, but the lightmap doesn’t actually tint anything. Hey presto, lightmapped fading terrain. Trying it without lighting and it looks pretty damn good (certainly it’s the best idea I’ve had so far on how to soften the edge - especially since it blends well into the skybox), so I reckon with this lightmapping it’ll be ‘perfick’, but of course I can’t track down the area to manually colour :confused:

(ydnar) #3

We experimented with that for the ocean water in Battery for a while.

You could do it, but use rgbGen vertex instead of the lightmap pass on the fading layer.

In reality, just buckling it so you can’t see the falloff from the field/helm’s deep castle thing should work fine, as long as you have a good skybox image.

y

(G0-Gerbil) #4

buckiling isnt an option - you can simply get too close to it.
And I can’t use rgbgen vertex because then that row won’t visually line up with the rest of the terrain because it’s lightmapped. Unless I manually edit the lightmap, which means I still need to be able to do what I’m asking here.

I can do it - trust me - I’m a rodent :slight_smile:

If I knew how to get all the terrain into one lightmap that is… :???:

(G0-Gerbil) #5

This is my edge - players can get (and indeed spawn at start) just over 1 terrain tile’s width away from it - hence I really need to fade:

(ydnar) #6

You are using lightmapped terrain with q3map_lightmapSize 512 512 in the base shader right?

You are compiling with -external, right?

I’d say just extend your terrain entity out, but using much larger triangles, bring it up into a hill, then bend it down out of view.

y

(G0-Gerbil) #7

Nah I was using easygen’s q3map2 output.
I trawled through the official map shaders and saw the difference straight away.
Once set up properly it did do as you’d expect. I love easygen more each day…

Anyway, I’ve got it all working correctly now, but of course have finally twigged why I think you believe it won’t work - because of the brightness / gamma settings.

IE what I paint as mid grey into the lightmap will be scaled up and down according to user settings, meaning it’ll never fade perfectly.

Would I be right? :slight_smile:

Anyway I really can’t afford the hills, nor do I want to - it’s not what’s in the map. Anyway, it’s made me think about combining methods - I make one row go to a neutral brightness by modifying the lightmap, then I make the final row next to it use vertex lighting (or full brightness using a muted texture might be easier) and fade that out using the alphagen.
So basically a 2 stage process.

Any thoughts?