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Weird effect near creased angles

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#1

Hi!
I’ve a strange problem with hard surfaces (not always though). As you see in the picture (circled in red), when I crease (also when I Subdivide the mesh) at the angles appears those weird “pointy edges” that interrupt the regular flowing of the surface.
Does anyone know why this happens and how to fix it?

Pointy%20edges

#2

This is just a byproduct of the subdivision process. There is no solution that fits every situation. Mixing creases/hardedges with smooth curved surface can by tricky, especially near the corners. There are a couple things you can try, but often you have to experiment with your topology until you find a configuration that produces acceptable results.

You can:

  1. Subdivide the surface to a higher resolution before performing your extrusions. You always want at least 1 point between a hard edge and another on a curved surface, or you will lose the curve. The more points there are on the surface, the better defined the curve will be making it less susceptible to deformation when subdividing, and the smaller the polygons will be, limiting the potential for distortion.
  • You’re having some trouble here because there is no other point between the last point on the curve near your hard corner. It results in a “flattening” of the curve in that polygon, and the distortion you are seeing. The larger the polygons, the more pronounced this effect is. You want the curve to be disrupted as little as possible.
  1. Change the way the topology is drawn. Instead of trying to define the corner with a single edge, define it with a triangular poly instead, so that a single point anchors the bottom, and two points define the corner where the distortion is occurring.
  1. Remember that two edges very close to each other have the same effect as a crease when subdividing, while also allowing a degree of control over how hard the edge is. You can often produce acceptable results by inserting another edge loop (horizontal or vertical, depending on the situation) that will reinforce the corner, instead of a crease. You can slide points closer to each other where you want to define a hard edge, and farther away from other points to avoid forming edges where you don’t want them.
  1. Perform your work at high poly with high poly tools instead if your intended output allows. This is an issue with Low poly modelling.
#3

Thanks Spyndel, i’ll try the methods you suggested, maybe an higher polycount could fix the issue.

#4

I do think your issue is mostly just not having a high enough resolution for the curved surface before performing your extrusions, but I neglected to mention the Spin Edge operation in Zmodeler. Sometimes these situations can be resolved or diminished by changing the way the edges are drawn between points. Spin edge is a quick way to try out different connections.

Also be sure to make use of Dynamic Subdivision when doing low poly work in order to preview a change non-destructively before committing to an actual subdivision.