several fixes to tessellation and extremely fast (in comparison) initial load of CAD objects

yacv_server/tessellate.py

@@ -2,15 +2,17 @@ import hashlib
 import io
 import re
 
-import numpy as np
+from OCP.BRep import BRep_Tool
 from OCP.BRepAdaptor import BRepAdaptor_Curve
 from OCP.GCPnts import GCPnts_TangentialDeflection
 from OCP.TopExp import TopExp
+from OCP.TopLoc import TopLoc_Location
 from OCP.TopTools import TopTools_IndexedMapOfShape
 from OCP.TopoDS import TopoDS_Face, TopoDS_Edge, TopoDS_Shape, TopoDS_Vertex
 from build123d import Shape, Vertex
 from pygltflib import GLTF2
 
+import mylogger
 from gltf import GLTFMgr
 
 
@@ -29,20 +31,16 @@ def tessellate(
     mgr = GLTFMgr()
     shape = Shape(ocp_shape)
 
-    # Triangulate all faces at the same time
-    # shape.mesh(tolerance, angular_tolerance)
-    _tessellate_face(mgr, shape.wrapped)
-
     # Perform tessellation tasks
-    # if faces:
-    #     for face in shape.faces():
-    #         _tessellate_face(mgr, face.wrapped)
-    # if edges:
-    #     for edge in shape.edges():
-    #         _tessellate_edge(mgr, edge.wrapped, angular_tolerance, angular_tolerance)
-    # if vertices:
-    #     for vertex in shape.vertices():
-    #         _tessellate_vertex(mgr, vertex.wrapped)
+    if faces:
+        for face in shape.faces():
+            _tessellate_face(mgr, face.wrapped, tolerance, angular_tolerance)
+    if edges:
+        for edge in shape.edges():
+            _tessellate_edge(mgr, edge.wrapped, angular_tolerance, angular_tolerance)
+    if vertices:
+        for vertex in shape.vertices():
+            _tessellate_vertex(mgr, vertex.wrapped)
 
     return mgr.gltf
 
@@ -54,24 +52,22 @@ def _tessellate_face(
         angular_tolerance: float = 0.1
 ):
     face = Shape(ocp_face)
-    # loc = TopLoc_Location()
-    # poly = BRep_Tool.Triangulation_s(face.wrapped, loc)
-    # if poly is None:
-    #     mylogger.logger.warn("No triangulation found for face")
-    #     return GLTF2()
+    face.mesh(tolerance, angular_tolerance)
+    poly = BRep_Tool.Triangulation_s(face.wrapped, TopLoc_Location())
+    if poly is None:
+        mylogger.logger.warn("No triangulation found for face")
+        return GLTF2()
     tri_mesh = face.tessellate(tolerance, angular_tolerance)
 
     # Get UV of each face from the parameters
-    # uv = [
-    #     [v.X(), v.Y()]
-    #     for v in (poly.UVNode(i) for i in range(1, poly.NbNodes() + 1))
-    # ]
-    uv = []
+    uv = [
+        (v.X(), v.Y())
+        for v in (poly.UVNode(i) for i in range(1, poly.NbNodes() + 1))
+    ]
 
-    vertices = np.array(list(map(lambda v: [v.X, v.Y, v.Z], tri_mesh[0])))
-    indices = np.array(tri_mesh[1])
-    tex_coord = np.array(uv)
-    mgr.add_face(vertices, indices, tex_coord)
+    vertices = [(v.X, v.Y, v.Z) for v in tri_mesh[0]]
+    indices = tri_mesh[1]
+    mgr.add_face(vertices, indices, uv)
 
 
 def _tessellate_edge(
@@ -84,37 +80,34 @@ def _tessellate_edge(
     discretizer = GCPnts_TangentialDeflection(curve, angular_deflection, curvature_deflection)
     assert discretizer.NbPoints() > 1, "Edge is too small??"
 
-    # TODO: get and apply transformation??
-
     # add vertices
-    vertices: list[list[float]] = [
-        [v.X(), v.Y(), v.Z()]
+    vertices = [
+        (v.X(), v.Y(), v.Z())
         for v in (
             discretizer.Value(i)  # .Transformed(transformation)
             for i in range(1, discretizer.NbPoints() + 1)
         )
     ]
-    mgr.add_edge(np.array(vertices))
+    mgr.add_edge(vertices)
 
 
 def _tessellate_vertex(mgr: GLTFMgr, ocp_vertex: TopoDS_Vertex):
     c = Vertex(ocp_vertex).center()
-    mgr.add_vertex(c)
+    mgr.add_vertex((c.X, c.Y, c.Z))
 
 
 def _hashcode(obj: TopoDS_Shape) -> str:
     """Utility to compute the hash code of a shape recursively without the need to tessellate it"""
     # NOTE: obj.HashCode(MAX_HASH_CODE) is not stable across different runs of the same program
     # This is best-effort and not guaranteed to be unique
-    data = io.BytesIO()
     map_of_shapes = TopTools_IndexedMapOfShape()
     TopExp.MapShapes_s(obj, map_of_shapes)
+    hasher = hashlib.md5(usedforsecurity=False)
     for i in range(1, map_of_shapes.Extent() + 1):
         sub_shape = map_of_shapes.FindKey(i)
         sub_data = io.BytesIO()
         TopoDS_Shape.DumpJson(sub_shape, sub_data)
         val = sub_data.getvalue()
         val = re.sub(b'"this": "[^"]*"', b'', val)  # Remove memory address
-        data.write(val)
-    to_hash = data.getvalue()
-    return hashlib.md5(to_hash, usedforsecurity=False).hexdigest()
+        hasher.update(val)
+    return hasher.hexdigest()