problem with spline-based procedual geometry (Unite15)

Unity Engine
1

Greetings,
I’m trying to recreate what was presented in the talk of @JoachimHolmer about ‘spline-based procedual geometry’ from Unite 2015.

The Talk:

The Slides (heavy images!): A coder's guide to spline-based procedural geometry - Google Slides

problem is, when I move or rotate the gameobject and then update the mesh, the mesh doubles everything I do:

Code (I will provide more if needed):

public struct OrientedPoint {
   public Vector3 position;
   public Quaternion rotation;

   public OrientedPoint(Vector3 pos, Quaternion rot) {
      position = pos;
      rotation = rot;
   }

   public Vector3 LocalToWorld(Vector3 point) {
      return position + rotation * point;
   }

   public Vector3 WorldToLocal(Vector3 point) {
      return Quaternion.Inverse(rotation) * (point - position);
   }
   public Vector3 LocalToWorldDirection(Vector3 dir) {
      return rotation * dir;
   }
}

(curve = OrientedPoint[ ])

private void SetMesh() {
   if (curveOK) {
      int vertsInShape = shape.vertices.Length;
      int edgeLoops = curve.Length;
      int vertCount = vertsInShape * edgeLoops;
      int triCount = shape.lines.Length * segments;

      int[] triIndices = new int[triCount * 3];
      Vector3[] vertices = new Vector3[vertCount];
      Vector3[] normals = new Vector3[vertCount];
      Vector2[] uvs = new Vector2[vertCount];

      for (int i = 0; i < curve.Length; i++) {
         int offset = i * vertsInShape;
         for (int n = 0; n < vertsInShape; n++) {
            int id = offset + n;
            vertices[id] = curve[i].LocalToWorld(shape.vertices[n]);
            normals[id] = curve[i].LocalToWorldDirection(shape.normals[n]);
            uvs[id] = new Vector2(shape.us[n], i / (float)edgeLoops);
         }
      }
      int ti = 0;
      for (int i = 0; i < segments; i++) {
         int offset = i * vertsInShape;
         for (int n = 0; n < shape.lines.Length; n += 2) {
            int a = offset + shape.lines[n] + vertsInShape;
            int b = offset + shape.lines[n];
            int c = offset + shape.lines[n + 1];
            int d = offset + shape.lines[n + 1] + vertsInShape;
            triIndices[ti] = c; ti++;
            triIndices[ti] = a; ti++;
            triIndices[ti] = b; ti++;
            triIndices[ti] = a; ti++;
            triIndices[ti] = c; ti++;
            triIndices[ti] = d; ti++;
         }
      }

      Mesh mesh = new Mesh();
      mesh.name = "CurvedMesh";
      mesh.vertices = vertices;
      mesh.triangles = triIndices;
      mesh.normals = normals;
      mesh.uv = uvs;
      mesh.RecalculateNormals();
      filter.sharedMesh.Clear();
      filter.sharedMesh = mesh;
   }
}

Tryed several things, and I think it has a problem with me also moving the curve corners (the grey and blue circles in the video. they are also gameobjects.). If I leave them unparented and don’t move them the mesh wont displace (when moving. rotating makes crazy things with the mesh that way). Any ideas how to fix this?

2

Just remembered, that there is a ‘localPosition’ property on transform (normally I never use that for anything). Now the moving part is working.
But rotating still messes up the mesh:

I feel like more code will be needed (this is called before SetMesh():

private void SetCorners() {
   if (shapeOK) {
      corners = new Vector3[] { start.localPosition, corner1.localPosition, corner2.localPosition, end.localPosition };
      cornersOK = true;
   }
}
private void SetCurve() {
   if (cornersOK) {
      float step = 1.0f / segments;
      curve = new BezierCurve.OrientedPoint[segments + 1];
      for (int i = 0; i < segments + 1; i++) {
         Vector3 pos = BezierCurve.CurvePoint(corners, step * i);
         Quaternion rot = BezierCurve.CurveOrientation3D(corners, step * i, transform.up);
         curve[i] = new BezierCurve.OrientedPoint(pos, rot);
      }
      curveOK = true;
   }
}
3

If you send me the full script i’ll take a look at it.