Light Functions

Azumante

I'm trying to make a flickering light in one of my levels, but whenever I click on the blue arrow to create a light function it doesn't do anything. I've been searching around for a couple of weks now and can't find anything relating to this problem, hoping one of you might know. Thanks.

Minato

As far as i can remember normal light classes(Pointlight,Spotlight,...) can't use light functions,try either movable,toggle-able or Dominant classes of those lights...maybe someone with a bit more info on this can explain this behavior...

Azumante

I have tried both moveable and toggleable for all of the different light types and none of them work.

blackterror

Here's a condensed version of making a simple flickering light using light functions:

Has to be a dynamic light - Move/Toggle
Create a spotlight MOVEABLE
In the content browser, create a new material
In the material’s properties, look under Material settings, set Blend mode to Translucent and Lighting Model to Unlit
Under mutually exclusive usage, activate Used As Light Function
Bring in a cloud texture using the Content Browser (this will give us random flicker in a few moments)
Plug the texture directly into the Emissive channel
Save the material
In the properties, look under Function
Click the little blue arrow and choose Function
Under the function’s properties, add the new material under Light Function Material
Your spotlight should now have a cloud gel
Back in your material, add a Panner (hold the P key and click)
Wire that into the texture to make it move
Save and see the results
Create a new TextureCoordinates node. Wire it into the Panner
Set the TexCoords to something VERY small (0.001 for x and y)
You’re now sampling a very small area, about a pixel
You need to boost the brightness at this point
Bring in a power node, add a constant of 3 or so, and use it to boost the texture before it plugs into the emissive channel

Let me know if you still can't get it. G'Luck!

Azumante

Yeah I've done all that I got it working one time, bui the first time I did it and now whenever I try to click the blue arrow nothing happens.

blackterror

Are you talking about the blue arrow in the light properties, as in mapping in the material? My only guess to that is making sure your package is fully loaded and you have it selected in the content browser before trying to map it in.

underfox

what kind of light are you using for your light function?

I had the same problem a few days ago, and discovered that only certain light can activate light function.

-dominant directional light
-directional light toggeable
-dominant point light
-Point light movable
-pointlight toggeable
-dominant spotlight
-spotlight movable
-spotlight toggeable

thos are the types of light that can use light fucntion.

and here is an explanation from unstoppablex.

unstoppablex wrote: »

yes, only real time lights can have light functions. this is because a material can be dynamic, with changing values. so the light also has to be dynamic

hope it helped.

Azumante

I have tried it with ever different type of light and the blue arrow still doesn't do anything when I click it.