Use PEP8. Fix NameError&note use. Switch to 2.79-2.80 code.

utilities/blender/generate_Empty_at_each_vertex.py

@@ -1,21 +1,23 @@
+#!/usr/bin/env python
+import bpy
+# from mathutils import Matrix
+from mathutils import Vector
+# from mathutils import Euler
+
 print("How to use: paste into a Blender Text Editor panel, select"
       " object, Run Script")
 
 y_up = True
 enable_minetest = True
 
-import bpy
-# from mathutils import Matrix
-from mathutils import Vector
-# from mathutils import Euler
 
 class MessageBox(bpy.types.Operator):
     bl_idname = "message.messagebox"
     bl_label = ""
     message = bpy.props.StringProperty(
-        name = "message",
-        description = "message",
-        default = ''
+        name="message",
+        description="message",
+        default=''
     )
 
     def execute(self, context):
@@ -34,26 +36,33 @@ class MessageBox(bpy.types.Operator):
         # col.prop(context.scene, "my_string_prop")
 
 
-ob1 = None
-try:
-    ob1 = obj.select_get()
-except:
-    # < 2.8
-    ob1 = bpy.context.scene.objects.active
+ob1 = bpy.context.active_object  # works with 2.7 or 2.8
+# try:
+#     # See <https://blender.stackexchange.com/questions/141330/
+#     #   problem-with-bpy-context-selected-objects>
+#     # for o in context.scene.objects:
+#     #     o.select_get() returns bool!
+#     # To select it automatically: o.select_set(bool)
+# except:
+#     # Blender version <= 2.79
+#     ob1 = bpy.context.scene.objects.active
 
 bpy.utils.register_class(MessageBox)
 
 if ob1 is None:
     msg = "Nothing is selected."
-    # WRONG: https://stackoverflow.com/questions/7697532/how-to-show-a-message-from-a-blender-script
+    # WRONG: <https://stackoverflow.com/questions/7697532/how-to-show-a-
+    #   message-from-a-blender-script>
     # self.report({'ERROR'}, msg)
-    bpy.ops.message.messagebox('INVOKE_DEFAULT', message = msg)
+    bpy.ops.message.messagebox('INVOKE_DEFAULT', message=msg)
 else:
 
     loc1 = ob1.location
     # loc1 = ob1.matrix_world.translation
 
-    # See https://blender.stackexchange.com/questions/6139/how-to-iterate-through-all-vertices-of-an-object-that-contains-multiple-meshes
+    # See <https://blender.stackexchange.com/questions/6139/how-to-
+    #   iterate-through-all-vertices-of-an-object-that-contains-
+    #   multiple-meshes>
     mesh = ob1.data
     # print("mesh:" + str(mesh))
     # print("hasattr(mesh, 'vertices'):" + str(hasattr(mesh,
@@ -68,7 +77,8 @@ else:
         xMax = None
         yMax = None
         zMax = None
-        # See https://blender.stackexchange.com/questions/6155/how-to-convert-coordinates-from-vertex-to-world-space
+        # See <https://blender.stackexchange.com/questions/6155/how-to-
+        #   convert-coordinates-from-vertex-to-world-space>
         wm = ob1.matrix_world
         newNamePrefix = "Empty.from." + ob1.name
         i = 0
@@ -80,7 +90,7 @@ else:
             except TypeError:
                 loc = wm * vert.co  # Blender <2.8
             # See also vert.co.x (and y and z)
-            bpy.ops.object.add(type='EMPTY', radius=.25, location=loc);
+            bpy.ops.object.add(type='EMPTY', radius=.25, location=loc)
             bpy.context.active_object.name = name
 
             # Also consider sambler's answer at