Realtime Lightmap Swapping?

Mr_Paris

Is it possible to swap between 2 lightmaps in-game? I was hoping to allow a player to turn a power generator on and off in a fairly complex section of my environment. When the lights are off emergency lighting is triggered showing a very different looking space. Strictly using triggerable dynamic lights wouldn't work nearly as well imo as having the 2 lighting schemes already baked in. Plus it's hard on the system.

So is there a way to swap out lightmaps dynamically? Or do UDK's lightmaps simply lack that sort of capability?

Thanks for any advice

ZacD

There's types of lights where you can change the color and intensity of the light after it has baked. I believe they are called toggleable

ambershee

A toggle light will indeed do it.

Mr_Paris

Aren't toggle lights just dynamic lights? Wouldn't that just overlay on top of the already baked map? Or are you suggesting using nothing but dynamic lights for the whole scene? Wouldn't that be harder on the engine?

Sorry, just trying to get a better/clearer idea of what you're suggesting.

ambershee

Toggle lights bake a set of static lightmaps for each viable combination of toggleable lights in the scene.

Mr_Paris

Oooohh ok. That's great to know. Thanks alot Amber & Zacd :thumbup:

sprunghunt

ambershee wrote: »

Toggle lights bake a set of static lightmaps for each viable combination of toggleable lights in the scene.

This does mean an extra shader pass per dynamic light. (unless you're using DX11 deffered rendering) Which is harder on the engine.

Mr_Paris

sprunghunt wrote: »

This does mean an extra shader pass per dynamic light. (unless you're using DX11 deffered rendering) Which is harder on the engine.

Good to know, thanks.

ambershee

sprunghunt wrote: »

This does mean an extra shader pass per dynamic light. (unless you're using DX11 deffered rendering) Which is harder on the engine.

No it doesn't; they're not dynamic lights (if you use it properly). It literally just switches the lightmap reference from one set to the other. The only time it starts to get sketchy is when toggle lights overlap.

Rooster128

I know this is an old thread (sorry for bumping old thread) but I was wondering... is it possible to use toggle lights to switch between two lightmaps inside one room or building, but still have a normal light bake outside the room (or outside the building) without artifacts and such going on?

Looking into toggle lights- sounds like the solution I need right now.

ambershee

I don't understand the question. All a toggle light does is bake one set of lightmaps for geometry that it is affecting - one with the light on, another with it off.

Rooster128

Right, but what if you have more static lights in the scene that are on no matter what? Will their light maps interfere with the toggle light maps?