I have a 3D complex shape composed of simpler primitive geometric shapes. The geometric shapes are made of triangles.
I already know how to draw the edges of a single object (geometric shapes). In this case I am comparing each pair of triangles that are adjacent and comparing its normals. If the normals are not the same then it's an edge, so I draw a line.
However, when combining primitive shapes to form a more complex shape (current rendering), I don't know how to remove the edges of the faces that are coplanar with the faces of the adjacent shape.
How can I know what lines are not anymore edges in the complex shape so I get the desired rendering?