Fix T61309: mesh_utils.triangle_random_points fails with a TypeError

Caused by an error in rBe65784a0519e.
And since we are going over loop triangles anyways, we can remove the
part quecking for quads [remainder of tessface era] entirely.

Reviewers: campbellbarton

Maniphest Tasks: T61309

Differential Revision: https://developer.blender.org/D4324

release/scripts/modules/bpy_extras/mesh_utils.py

@@ -454,19 +454,6 @@ def triangle_random_points(num_points, loop_triangles):
         tv = (verts[ltv[0]].co, verts[ltv[1]].co, verts[ltv[2]].co)
 
         for k in range(num_points):
-            # If this is a quad, we need to weight its 2 tris by their area
-            if len(tv) != 1:
-                area1 = area_tri(*tv[0])
-                area2 = area_tri(*tv[1])
-                area_tot = area1 + area2
-
-                area1 = area1 / area_tot
-                area2 = area2 / area_tot
-
-                vecs = tv[0 if (random() < area1) else 1]
-            else:
-                vecs = tv[0]
-
             u1 = random()
             u2 = random()
             u_tot = u1 + u2
@@ -475,10 +462,10 @@ def triangle_random_points(num_points, loop_triangles):
                 u1 = 1.0 - u1
                 u2 = 1.0 - u2
 
-            side1 = vecs[1] - vecs[0]
+            side1 = tv[1] - tv[0]
-            side2 = vecs[2] - vecs[0]
+            side2 = tv[2] - tv[0]
 
-            p = vecs[0] + u1 * side1 + u2 * side2
+            p = tv[0] + u1 * side1 + u2 * side2
 
             sampled_points[num_points * i + k] = p