What's the problem in this example? I don't quite understand what the pictures want to imply.

churchill

I think the idea is that approximating vertex positions very well does not guarantee that other properties of the shape are preserved. In this particular example, the approximation of the cylinder using more points gives a worse representation of the area than the approximation using fewer points because the surface normals of the triangles differ more from the true surface normal of the cylinder.

What's the problem in this example? I don't quite understand what the pictures want to imply.

I think the idea is that approximating vertex positions very well does not guarantee that other properties of the shape are preserved. In this particular example, the approximation of the cylinder using more points gives a worse representation of the area than the approximation using fewer points because the surface normals of the triangles differ more from the true surface normal of the cylinder.