Normal hard weird edges

[kumaran7]

Hard edges in normal map.how can i fix this problem.

[Dade]

Can you post the scene ?

[wasd]

My wild guess is that normal map doesn't respect Phong normals. So, Phong normal should be calculated first, then normal from map added. But it seems (I didn't read the actual code) that normal map added to surface normal, ignoring Phong interpolation.

Here's my example scene

bump_terminator-c.blend

(2.79 MiB) Downloaded 146 times

[kintuX]

Use Normal Height value below 3 cm = 0.03.
eg. h = 3cm / without Subdivision, as you can observe artifact starts appearing

[wasd]

Use Normal Height value below 3 cm = 0.03.
eg. h = 3cm / without Subdivision, as you can observe artifact starts appearing

bump_terminator-c@3cm(=0.003).jpg

1.) As far as I know normal "Height" is not in meters, it's 0-100%. At 0 it's no change to initial normal; at 1 it's 100% added map value.
2.) My guess must be wrong, because at 0 Height the surface is smoothed.

No normal map, flat

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No normal map, smoothed

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Yes normal map, Height = 0

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Yes normal map, Height = 1

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3.) My another observation: it's the same faces that experience terminator problem are affected by the "normal map problem". Faces affected by terminator problem has sharp edges, but smoothed at the middle. With normal map they look flat.

Normal map

Terminator

File with cylinder

bump_terminator-d.blend

(2.84 MiB) Downloaded 145 times

4.) My another wild guess is that the problem lies somewhere in clipping combined normals.

[wasd]

Normal map Height = 2.45

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No bump

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Normal map Height = 0.3

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https://github.com/LuxCoreRender/LuxCor ... malmap.cpp

Code: Select all

// Transform n from tangent to object space
	Normal shadeN = Normal(Normalize(hitPoint.GetFrame().ToWorld(n)));
	shadeN *= (Dot(oldShadeN, shadeN) < 0.f) ? -1.f : 1.f;

If normal is pointing wrong way it is reversed?

[Dade]

Normal map Height = 2.45

Use Normal Height value below 3 cm = 0.03.

[wasd]

Normal map Height = 2.45

Use Normal Height value below 3 cm = 0.03.

It's not 3 cm though.

When normal is pointing outward the camera is should be clipped at near perpendicular, not inverted.
Setting so-called "Height" multiplier doesn't solve anything.