Hi PaQ, I guess it's just due to the particular way this surface is straight in one direction and has a particular amount of curvature in its other direction, that just meshing by an angle parameter alone makes some pieces of it to be subdivided and another area right next to it to not be subdivided, making for long and skinny polygons sitting right next to some subdivided ones. When you get a situation like that it's pretty easy to get shading glitches.
Like Burr says above if you use the "Divide larger than" meshing parameter, it should help to solve this - put in for example 1.0 or 0.5 in the "Divide larger than" meshing option and then look at the mesh wireframe, you should see that it doesn't have any long skinny triangles spanning the entire length of the surface anymore and should work better.
When you have long skinny triangles, any slight shape changes at the ends of the triangles tends to make for low-poly type shading glitches.
I don't think there's anything really wrong with the red surface, it's just that due to its particular shape you'll get low poly like shading glitches if it gets long skinny polygons being made right next to some subdivided polys, and meshing by the angle parameter alone just happens to give that kind of result.
- Michael
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