Spherical Tilt

I thought that spherify by byRo LINK might help, but it doesn't seem to do the trick.

I think that perhaps something with curves needs to happen in the gradient offset map.

This is better, but only partially wrapping ...

Somewhat interesting effect

Here is the filter

_SphereTwist3.ffxml

Here's the image:

It actually tilts!

Here's the file:

_SphereTwist7.ffxml

Definitely a strange effect. It seems to help to have seamless tiling on.

So, of course I had to try it -- this one almost works.



If I can get the distortion to match the diagram, it probably will.

It isn't geometrically correct nor perfect, but it looks pretty good now.



You can see how much I had to bloat it to make it look like a sphere by looking at the size difference of the squares at the equator in the first and the last render.

And no, it certainly wasn't too easy to do.

There shall be snippets.

Maybe "3D" planets with those nebulae aren't such a far-fetched idea...

Exciting times!

Oh, I thought that devil was more fitting to the occasion!

That's awesome. I can't believe you figured that out so fast, ThreeDee. (I think my brain is still in a knot from trying the stuff I did.) How the @#$% do you figure this stuff out?

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CorvusCroax wrote: That's awesome. I can't believe you figured that out so fast, ThreeDee. (I think my brain is still in a knot from trying the stuff I did.) How the @#$% do you figure this stuff out?

I like these "is this even possible in FF?" challenges.

In this case it must have something to do with geometry being one of my favorite subjects and my fascination with different mapping systems ("Mapping" as in world atlas). I first tried to figure out if there is a way to simply rotate a texture spherically but I couldn't do it, so next I asked myself what is halfway between where I'm starting from and where I want to get to. The primary problem seemed to be the poles and the tilting on X-axis, so I got the idea of making an intermediate flat map that already has the poles. In a way polar mapping is a combination of cylindrical mapping in three coordinate directions, so somewhere there the solution loomed.

In fact, if you had asked me 6 months ago whether this transformation was possible in FF, I would probably have said 'no.'

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CorvusCroax wrote: btw: have you ever thought of writing an 'Understanding Offset' page / tutorial over at 'dilla's dos and don't Wiki?

I was thinking about it. Seemed like quite a bit of work, but perhaps doing it one offset feature at a time it wouldn't sound like too much to undertake.

Just kidding!

Ponch says 'You the man!'

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ThreeDee wrote: I like these "is this even possible in FF?" challenges.

I've noticed that.....and PLEASE don't stop!!!

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Crapadilla wrote: You'd defininitely be THE person to do it

+2 Definitely.....

I'm glued to my computer 24/7 just to see what's next.....

So, downloaded the filter and started messing around with it. Wow complicated. I noticed that there are a couple strange things going on. (see image)
1) The underlying pattern is actually reflected once across the 'globe'. So, if you look at the test pattern, C1 and C8 are reflecting.

2) At certain angles, for some reason, the hemispheres 'double' and you get the 'north' hemisphere in both the north and the south, mirrored again.

I suspect that on both, something is a half a step off, or something.

Hi Corvus,

I can fix some of those things, but not necessarily all. After all, this is NOT true spherical mapping but a simulation that is trying to look like one.

Here's what I could do to fix the tiling, so it isn't mirroring:



Since it is simulated spherical mapping, it tends to look better with repeated pattern.



By the way, in the current version the number of repeats is a bit odd, at Repeat value 2 (as in the above image) you actually get 3 repeats. I probably should fix that as well.

Is this how you want to map it (rendered in a 3D program)?



I think I can get it at least somewhat close to that.

Above snippet output looks like this:

BTW ThreeDee; if you wanted help doing an 'understanding offsets' wiki article, I'd be more than happy to help. (I might actually learn something in the process. )

This is very interesting and useful

Great work and thanks for sharing this filters plus the ones already available in the FF library