Light function color desaturation bug

Development Rendering
1

Why is light function in UE4.7.3 colorless by default?
It is some settings to make it work like in UDK: color function + white light = color spot on wall?

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UE4 vs. UDK
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2

Hi Shipo,

In the documentation on Light Functions this is already mentioned.

Unreal Engine 4 has only been publicly available for a little over a year and is still being actively developed. It’ll take a while to implement a lot of the features that UE3/UDK had, if there are even plans to with some. This may be added in the future though. Some features, however, may never be brought over though.

With Light Functions you can fake color by setting up three lights with three materials (can probably condense down to one and use material instances, but I just threw this together quickly).

Here are the results:

SoniceLightFunction.png
SoniceLightFunction.png759×896 501 KB

  1. Top row is each light function with it’s corresponding material with the light color changed to the full RED, GREEN, or BLUE channel.
  2. The Middle is the final result of the combined Lights over top each other.
  3. Bottom row is each light function with just the corresponding material using the RGB channel. The lights color has not been set yet.

Material Setup:

SoniceLightFunction.png
SoniceLightFunction.png759×896 466 KB

I hope this helps. :slight_smile:

1 Like
3

Thank you Tim Hobson, idea helped me a lot. :slight_smile:

Triples lights/materials eat some performance, but isn’t too bad as i thought:
0L = 50fps
1L = BW = 47fps
3L = RGB = 38fps

For nine instances of a Blueprint:
9L = BW = 25fps
27L = RGB = 12,5fps

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