Spheres are not perfectly round

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  01 January 2013
Originally Posted by Broodstar: I am trying to have it low poly though...512 is just insane.

Not really, remember there is viewport resolution, and render resolution. Changing the uv values sees in the viewport what render resolution is needed.
  01 January 2013
This is really interesting from an academic viewpoint, but...

I noticed this a long time ago, especially after putting it into SubD. I just squash it a little in the Y axis until it looks about right and then I forget about it and pretend it's a sphere. Seems to have worked so far. That is to say, nobody has ever said "hey dude, your spheres aren't round enough."
  01 January 2013
The distortion (or skewing) would happen to any type of object (not just spheres) that was off the screen's center. It's the nature of the beast.

In general, it happens because of the perspective projection.
e.g. A sphere in the center on the screen is projected perpendicularly to the view plane (imagine a line from the screen to the center of that sphere). The sphere is projected as a circle as it should.
A sphere on the right side of the screen is projected on a skewed angle onto the view plane and will show up as some sort of ellipse instead of a circle.
Zoom the camera out and to the left, and the ellipse effect will be more pronounced.

Animations are mostly fine since the camera will follow the moving object of interest and that will always be projected perpendicularly to the view plane.

What to do other than live with it?

1. Move the camera away since the rotation effect disappears at long distances, or even increase the field of view to compress the objects towards the center.
2. Don't use perspective projection.

Reminded me the EGA days and the money I spent on Number Nine's Pepper cards thinking it was a low resolution problem.
  01 January 2013
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