title: Is there a way to extract geometric information out of cad model for feature recognition?
body: <p>I am really new to this so any help is appreciated so basically I am trying to use PyTorch geometric to identify topological features within 3D CAD models (i.e. slots, pockets, holes, etc) but in order to do that I need to represent the cad model into a graph in PyTorch geometric.
  For the input data, I am thinking of using adjacency of the faces to identify the features within the model.</p>
  <p>Below is an example that is what I want to achieve out of a 3D model. The
  relationships between each face are represented in a graph format.</p>
  <p><a href="https://i.stack.imgur.com/3DA4I.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/3DA4I.png" alt="enter image description here" /></a></p>
  <p>So after getting the above graph I want to feed that to the algorithm for the graph classification.
  The issue that I am facing is how can I extract that adjacency information out of the CAD model (i.e. Let's say face 1 is connected to face 3 so I take the 2 faces as two nodes in the graph and connect the two-node with an edge as both faces are touching each other) makes a graph out of it as shown in the above image.</p>
  <p>I did come across one tool called pythonOCC not sure I can use that to extract the adjacency information out of it, if possible please suggest what I can do using that tool.</p>