Material Noise node produces values out of range

Development Asset Creation
, , , ,
1

Currently using 4.7.3.

The material Noise node can produce values considerably greater than its Output Max. Simplex and Gradient noise produce these values with the default settings. I only saw Perlin and FastGradient produce values outside of range with a Level Scale between -1 and 1. I only saw values below Output Min when Level Scale was between -1 and 0.

The image below was produced with all default node settings.

36384-noisebug.jpg
36384-noisebug.jpg1920×1080 337 KB

Edit: Multiple levels with Level Scale 1 produce the issue, as does a single level with a Level Scale other than 1. With 1 level and Level Scale 1, I’m not seeing the issue. Also using a Custom node with:

return SimplexNoise3D_TEX(EvalPos);

and Input Name: EvalPos appears to produce a uniform distribution.

2

Hi xnihil0zer0 -

Thank you for your report. I have entered a bug report for this issue, for reference UE-13074. We believe that this issue may be a result of float point error used in the calculation process, but we are investigating this issue currently and as we know more I will let you know here.

Thank You Again -

Eric Ketchum

3

Have also run into this recently, looks like it’s marked as Won’t Fix due to lack of updates. Any chance of re-opening?

4

Also ran into this recently… Any chance of reopening?

Really don’t wanna make a noise function from scratch, you know how much maths that is?

5

Here is another case (UE 5.3):

image
image1413×964 202 KB

Coordinates as entered are (-232.4, -145.3, 55.5)

This is what it looks like in-game:

image
image1920×909 33.9 KB

In the screenshot above, simplifying a bit, I combined the noise with a radius and check if the value is positive or not to create a halo effect (the white color on the outer edge). The colored quadrants are what I used to located the coordinates of the glitch.
Note the three white dots in the middle of the halo, and especially the size of the middle dot.