Normal map weirdness

[monkriss]

I've just started out with Corona and one of my biggest issues is that if i get a normal map, plug it into the normal map node and then output from DirectX and set it to "1", it works. But if i try to increase the strength to anything more than 1, it goes really weird and creates very odd shadows?

It doesn't increase the normal strength either, just creates unnecessary shadowing and looks terrible.

You can see in the images that Strength 1 looks far better than Strength 5. Is this an error? am i doing something wrong? I've love to increase normal strength just like in Cycles...




https://imgur.com/g7JmHQO
https://imgur.com/H48wuJT

[blanchg]

Hi monkriss,

I will have a look when I can but currently I don't have access to a windows machine to develop or test against.

Apologies

Glen.

[monkriss]

No problem :)

[monkriss]

I don't suppose anyone else is having issues with Normal maps? I just wonder if i'm using it incorrectly

[burnin]

NOTE:
- no displacement in corona SA
- only bump (using either N or B maps)
- unreasonably high values produce artifacts

PS
1 Blender Unit = 1m

[monkriss]

Sorry, are you agreeing with me there? haha

I know there is no displacement, only N and B maps.

Is a normal strength of 2 considered unreasonable?.... i get artefacts with anything over 1 which seems unreasonable.

I know in my example i tried using a value of 5, but that too doesn't seem unreasonable. I can barely see some normal maps with just a strength of 1

[blanchg]

Try much lower values, like 0.001 which equals 1 mm of bump.  0.01 is 1 cm of bump

[burnin]

:D rinse - repeat - think, consider UNITS!
(as mentioned in PS posted above & explained again by blanchg)

[monkriss]

Sorry i feel like i'm completely missing the point :(..

Sorry if i'm being a pain but i did a test. At 0.001 the normal map is completely invisible. Almost all the way up until about 0.5.
At 1 it looks okay but i cannot exceed 1.

Here are two gifs
Corona normal map strengths:
https://imgur.com/a/fOcGd

Cycles normal map strengths
https://imgur.com/a/7YXAV

[burnin]

:) no problem
Just post your scene & material settings (be sure to use correct scale & so on)
Best would be if you provide the test scene, to have facts at hand.

i.e.
Here's 8k normal map on a sphere (r=1m): Grass Cut from megascans
(from left to right) Bump Strength: 1 m, 5 cm, 10 m 

[melviso]

I have to second what monkris is saying. I am having this issue as well. This seems to apply to bump maps too. Both normal and bump maps don't show any effect after the vaule 1 . Neither do they affect the lighting in anyway.

In cycles or 3dsmax, this is not an issue. With 3dsmax, corona bump and normal work correctly even when using high vaules.
@burnin Even from the image u have posted, the bump at 5cm doesn't seem to affect the lighting.
Is there anyway this can be looked into. Unfortunately, I am using Corona right now, and I have gone too far to switch in the project.

Thanks :-)

[burnin]

affect on how the surface is lit (0.05 (5cm) on the middle sphere) can be observed - very subtle, but visible ;)

& as mentioned few times already, standalone version only uses simple/cheap bump technique for this effect - ai, no miracles to be expected

[melviso]

& as mentioned few times already, standalone version only uses simple/cheap bump technique for this effect - ai, no miracles to be expected

Thanks for the info, will try and see if there is a workaround sort of. I guess it will have to make do. Thanks :)