These normals! They have always confused me.

If I scale a normal (say 100 times larger)
are the normal patterns still the same depth
relative to their size on the surface?

It seems to me that it depends on the pattern
used and I find that confusing.

OK I have a sphere with a bozo normal.
Now I scale the sphere 100 times larger
BEFORE the normal is added and I also scale
the camera and light_source 100 times larger.
To make the normal look the same way as before
I scale it 100 times larger, but I also have
to multiply the pattern depth by 100 (bozo 1
becomes bozo 100). Now the normal looks the
same as before.

So if you scale a normal X times larger you
also have to multiply the depth of the pattern
with X.

That is true for some patterns but for others
it isn't.

Now, I have a sphere with bumps pattern.
I scale the sphere 100 times larger (before the
normal is added) and I also scale the normal
100 times larger. Now I thought I'd also have to
multiply the pattern depth with 100 but I don't!

I only have to do that with the patterns which
were not original meant to be used in normals.
Am I right here?

OK but here's something that REALLY confuses me:

I have a sphere with a normal with one of these
patterns that were not original meant to be used
in normals.
Now the sphere doesn't fit in my scene. It is 100
times too big. So I want to scale down the whole
sphere with normal and everything.
I do so and suddenly the normal pattern is 100
times deeper! So deep that the before light shaded
areas is now totally black spots.

Is that a bug?
How can I scale up or down an object without
ruining the normals?

I don't want a man in my scene who are 100 times
too big!
But I also don't want a regular man who have folds
in his clothes so deep that half of his white shirt
are shaded totally black and with skin that makes
you think he has some kind of disease!

Thank you for your help and enlightenment!

Greetings,

Rune S. Johansen

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