title: how to determine OpenGL winding based on normals?
body: <p>I am trying to understand how to manually generate objects.</p>
  
  <p>I have a mesh, part of which I delete and create a new geometry in its place. I have information about the normals of deleted vertices. On the basis of which I have to build new faces (in a different size and quantity) looking in the same direction.</p>
  
  <p>But I don’t understand how to choose the correct winding.  It sounds easy when the lessons talk about CCW winding in screen space.  But what if I have a bunch of almost chaotic points in the model space?  How then to determine this CCW, which axis is used for this?  I suggest that the nearest old normals might help.  But what is the cheapest method to determine the correct order?</p>