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I was rendering a 3D eye where i have a 'glint' on the upper-left side of the object, and it looks like a white circle (just like in the image) the problem is that i animated the camera into the black part of the texture, and when it reach some point the texture looks weird the geometry 'shows too much' and the light doesn't look right...i know the model isn't totally a perfect sphere but maybe there's a way to only fix that light. Is that possible?

enter image description here

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  • $\begingroup$ adding a loop cut inside that red circle will get rid of the glitches $\endgroup$ – Chebhou Feb 9 '15 at 12:26
  • $\begingroup$ The issue is you are using a non-symmetrical sphere type, the UV sphere has these artifacts when subdivided, similar to cylinders. An icosphere reacts much better to subdivision. $\endgroup$ – VRM Feb 9 '15 at 12:36
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To make a perfectly spherical sphere, that responds well to modifiers, you need to use an Icosphere. This is a spherical mesh made from congruent triangular faces:

Icosphere

When using smooth shading or a subdivision modifier, there are no artifacts as all the faces are exactly the same in size and shape.

In contrast, a UV Sphere is made up in the manner of a globe, with degrees of Longitude and Latitude:

UV Sphere

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  • $\begingroup$ Icsphere is perfectly even, but not suited for things like crystalline lens modeling. A workaround is to use a UV sphere and "quadify" the bad star pole(s). This can be done by merging faces (tri+tri = quad) but not so good. Another way is to delete the center vertex and to use face menu/grid fill (Ctrl+F for menu). Nothing's perfect... $\endgroup$ – Bithur Feb 9 '15 at 19:29
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As others have pointed out the issue is from the triangulated points on a uv sphere. You only see the issue if you have the triangulated part at the front of the eye, if you rotate the sphere 90 degrees it won't be visible, because that section will be hidden behind the eyelid.

Another option is to use a polyshere, which is a sphere made of square polygons. You can make one by adding a subsurf of level 3 to a cube and applying the modifier. You will also want to use To Sphere in edit mode to get it 'rounder' with ⇧ Shift ⎇ Alt S

enter image description here

Or a simpler way is to enable the Extra Objects addon and you will find a polyshere in your add mesh menu.

enter image description here

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    $\begingroup$ If you do start with a cube and a Sub-surf modifier, you should apply the modifier and then use 'To Sphere'-(Alt+Ctrl+s) while in Edit mode to round it out because the subdivision modifier leaves the sphered-cube a bit out of shape. $\endgroup$ – MarcClintDion Feb 10 '15 at 20:46
  • $\begingroup$ I did think of the to sphere step but seem to have missed it. add it now. $\endgroup$ – sambler Feb 11 '15 at 1:04
  • $\begingroup$ You don't have to apply the subsurf, you can use a 'Cast' modifier with a factor of '1'. $\endgroup$ – Ray Mairlot May 17 '16 at 14:53

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