Fix T51618: Add a warning message override, poll check

Bumped version to 1.0.2
Add a poll for the bpy.app.path is not an empty string
that can happen if the file is not saved
Add and override to the warning_messages that will allow to
show up the message no matter what the setting is
Small UI fixes

5 files changed, 181 insertions, 174 deletions

diff --git a/materials_utils/__init__.py b/materials_utils/__init__.py
index 09342408..c001a882 100644
--- a/materials_utils/__init__.py
+++ b/materials_utils/__init__.py
@@ -15,24 +15,24 @@
 #  Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 #
 # ##### END GPL LICENSE BLOCK #####
+
 #  (c) 2016 meta-androcto, parts based on work by Saidenka, lijenstina
-#           Materials Utils: by MichaleW, lijenstina,
-#                           (some code thanks to: CoDEmanX, SynaGl0w,
-#                                                 ideasman42)
-#           Materials Conversion: Silvio Falcinelli, johnzero7#,
-#                                  fixes by angavrilov and others
-#           Link to base names: Sybren, Texture renamer: Yadoob
+#  Materials Utils: by MichaleW, lijenstina,
+#       (some code thanks to: CoDEmanX, SynaGl0w, ideasman42)
+#  Materials Conversion: Silvio Falcinelli, johnzero7#,
+#        fixes by angavrilov and others
+#  Link to base names: Sybren, Texture renamer: Yadoob
 
 bl_info = {
     "name": "Materials Utils Specials",
     "author": "Community",
-    "version": (1, 0, 1),
+    "version": (1, 0, 2),
     "blender": (2, 77, 0),
-    "location": "Materials Properties Specials/Shift Q",
-    "description": "Materials Utils & Convertors",
+    "location": "Materials Properties Specials > Shift Q",
+    "description": "Materials Utils and Convertors",
     "warning": "",
-    "wiki_url": "https://wiki.blender.org/index.php/Extensions:2.6/Py/Scripts/3D_interaction/Materials_Utils",
-    "tracker_url": "",
+    "wiki_url": "https://wiki.blender.org/index.php/Extensions:2.6/Py/"
+                "Scripts/3D_interaction/Materials_Utils",
     "category": "Material"
     }
 
@@ -51,29 +51,30 @@ else:
 import bpy
 import os
 from os import (
-            path as os_path,
-            access as os_access,
-            remove as os_remove,
-            )
+        path as os_path,
+        access as os_access,
+        remove as os_remove,
+        )
 from bpy.props import (
-            StringProperty,
-            BoolProperty,
-            EnumProperty,
-            )
+        StringProperty,
+        BoolProperty,
+        EnumProperty,
+        PointerProperty,
+        )
 from bpy.types import (
-            Menu,
-            Operator,
-            Panel,
-            AddonPreferences,
-            PropertyGroup,
-            )
+        Menu,
+        Operator,
+        Panel,
+        AddonPreferences,
+        PropertyGroup,
+        )
 from .warning_messages_utils import (
-            warning_messages,
-            c_data_has_materials,
-            )
+        warning_messages,
+        c_data_has_materials,
+        )
 
 
-# Functions #
+# Functions
 
 def fake_user_set(fake_user='ON', materials='UNUSED', operator=None):
     warn_mesg, w_mesg = '', ""
@@ -420,8 +421,7 @@ def cleanmatslots(operator=None):
             bpy.ops.object.mode_set(mode='EDIT')
 
 
-# separate edit mode mesh function
-# (faster than iterating through all faces)
+# separate edit mode mesh function (faster than iterating through all faces)
 
 def assign_mat_mesh_edit(matname="Default", operator=None):
     actob = bpy.context.active_object
@@ -733,8 +733,7 @@ def remove_materials_all(operator=None):
 class VIEW3D_OT_show_mat_preview(Operator):
     bl_label = "Preview Active Material"
     bl_idname = "view3d.show_mat_preview"
-    bl_description = ("Show the preview of Active Material \n"
-                      "and context related settings")
+    bl_description = "Show the preview of Active Material and context related settings"
     bl_options = {'REGISTER', 'UNDO'}
 
     is_not_undo = False     # prevent drawing props on undo
@@ -1193,9 +1192,8 @@ class VIEW3D_OT_fake_user_set(Operator):
 class MATERIAL_OT_set_transparent_back_side(Operator):
     bl_idname = "material.set_transparent_back_side"
     bl_label = "Transparent back (BI)"
-    bl_description = ("Creates BI nodes with Alpha output connected to"
-                      "Front/Back Geometry node \n"
-                      "on Object's Active Material Slot")
+    bl_description = ("Creates BI nodes with Alpha output connected to Front/Back\n"
+                      "Geometry node on Object's Active Material Slot")
     bl_options = {'REGISTER', 'UNDO'}
 
     @classmethod
@@ -1346,8 +1344,7 @@ class MATERIAL_OT_link_to_base_names(Operator):
         return context.window_manager.invoke_props_dialog(self)
 
     def replace_name(self):
-        # use the chosen material as a base one
-        # check if there is a name
+        # use the chosen material as a base one, check if there is a name
         self.check_no_name = (False if self.mat_keep in {""} else True)
 
         if self.check_no_name is True:
@@ -1356,7 +1353,7 @@ class MATERIAL_OT_link_to_base_names(Operator):
                 if name == self.mat_keep:
                     try:
                         base, suffix = name.rsplit('.', 1)
-                        # trigger the except
+                        # trigger the exception
                         num = int(suffix, 10)
                         self.mat_keep = base
                         mat.name = self.mat_keep
@@ -1376,7 +1373,7 @@ class MATERIAL_OT_link_to_base_names(Operator):
         base, suffix = name.rsplit('.', 1)
 
         try:
-            # trigger the except
+            # trigger the exception
             num = int(suffix, 10)
         except ValueError:
             # Not a numeric suffix
@@ -1442,18 +1439,17 @@ class MATERIAL_OT_link_to_base_names(Operator):
 class MATERIAL_OT_check_converter_path(Operator):
     bl_idname = "material.check_converter_path"
     bl_label = "Check Converters images/data save path"
-    bl_description = ("Checks if the given path is writeable \n"
-                      "(has OS writing privileges)")
+    bl_description = "Check if the given path is writeable (has OS writing privileges)"
     bl_options = {'REGISTER', 'INTERNAL'}
 
-    @classmethod
-    def poll(cls, context):
-        return True
-
     def check_valid_path(self, context):
         sc = context.scene
         paths = bpy.path.abspath(sc.mat_specials.conv_path)
 
+        if bpy.data.filepath == "":
+            warning_messages(self, "DIR_PATH_EMPTY", override=True)
+            return False
+
         if os_path.exists(paths):
             if os_access(paths, os.W_OK | os.X_OK):
                 try:
@@ -1463,13 +1459,13 @@ class MATERIAL_OT_check_converter_path(Operator):
                     os_remove(path_test)
                     return True
                 except (OSError, IOError):
-                    warning_messages(self, 'DIR_PATH_W_ERROR')
+                    warning_messages(self, 'DIR_PATH_W_ERROR', override=True)
                     return False
             else:
-                warning_messages(self, 'DIR_PATH_A_ERROR')
+                warning_messages(self, 'DIR_PATH_A_ERROR', override=True)
                 return False
         else:
-            warning_messages(self, 'DIR_PATH_N_ERROR')
+            warning_messages(self, 'DIR_PATH_N_ERROR', override=True)
             return False
 
         return True
@@ -1477,13 +1473,13 @@ class MATERIAL_OT_check_converter_path(Operator):
     def execute(self, context):
         if not self.check_valid_path(context):
             return {'CANCELLED'}
-        else:
-            warning_messages(self, 'DIR_PATH_W_OK')
+
+        warning_messages(self, 'DIR_PATH_W_OK', override=True)
 
         return {'FINISHED'}
 
 
-# Menu classes #
+# Menu classes
 
 class VIEW3D_MT_assign_material(Menu):
     bl_label = "Assign Material"
@@ -1759,19 +1755,17 @@ class MATERIAL_PT_scenemassive(Panel):
                        text="Convert All to Cycles", icon='MATERIAL')
         split.operator("ml.refresh_active",
                        text="Convert Active to Cycles", icon='MATERIAL')
-        box = box.box()
-        ml_restore = box.operator("ml.restore",
-                                  text="To BI Nodes Off",
+        row = box.row()
+        ml_restore = row.operator("ml.restore", text="To BI Nodes Off",
                                   icon='MATERIAL')
         ml_restore.switcher = False
         ml_restore.renderer = "BI"
 
-        row = layout.row()
-        box = row.box()
-        box.menu("scenemassive.opt", text="Advanced Options", icon='SCRIPTWIN')
-        box = row.box()
-        box.menu("help.biconvert",
-                 text="Usage Information Guide", icon='MOD_EXPLODE')
+        box = layout.box()
+        row = box.row()
+        row.menu("scenemassive.opt", text="Advanced Options", icon='SCRIPTWIN')
+        row.menu("help.biconvert",
+                 text="Usage Information Guide", icon="INFO")
 
         box = layout.box()
         box.label("Save Directory")
@@ -1804,18 +1798,15 @@ class MATERIAL_PT_xps_convert(Panel):
         split.operator("xps_tools.convert_to_cycles_selected",
                        text="Convert Selected to Nodes", icon="TEXTURE")
 
-        col = layout.column()
-        row = col.row()
-        box = row.box()
-        ml_restore = box.operator("ml.restore",
-                                  text="To BI Nodes ON",
+        box = layout.box()
+        row = box.row()
+        ml_restore = row.operator("ml.restore", text="To BI Nodes ON",
                                   icon='MATERIAL')
         ml_restore.switcher = True
         ml_restore.renderer = "BI"
 
-        box = row.box()
-        box.menu("help.nodeconvert",
-                 text="Usage Information Guide", icon="MOD_EXPLODE")
+        row.menu("help.nodeconvert",
+                 text="Usage Information Guide", icon="INFO")
 
 
 # Converters Help #
@@ -1891,7 +1882,7 @@ class MATERIAL_MT_nodeconv_help(Menu):
         layout.label(text="Convert Materials/Image Textures from Imports:", icon="INFO")
 
 
-# Make Report #
+# Make Report
 class material_converter_report(Operator):
     bl_idname = "mat_converter.reports"
     bl_label = "Material Converter Report"
@@ -1902,14 +1893,12 @@ class material_converter_report(Operator):
 
     def draw(self, context):
         layout = self.layout
-        box = layout.box()
-
-        box.label(text="Converter Report", icon='INFO')
+        layout.label(text="Information:", icon='INFO')
 
         if self.message and type(self.message) is str:
             list_string = self.message.split("*")
             for line in range(len(list_string)):
-                box.label(text=str(list_string[line]))
+                layout.label(text=str(list_string[line]))
 
     def invoke(self, context, event):
         return context.window_manager.invoke_props_dialog(self, width=500)
@@ -1919,7 +1908,6 @@ class material_converter_report(Operator):
 
 
 # Scene Properties
-
 class material_specials_scene_props(PropertyGroup):
     conv_path = StringProperty(
             name="Save Directory",
@@ -1990,7 +1978,6 @@ class material_specials_scene_props(PropertyGroup):
 
 
 # Addon Preferences
-
 class VIEW3D_MT_material_utils_pref(AddonPreferences):
     bl_idname = __name__
 
@@ -2004,10 +1991,9 @@ class VIEW3D_MT_material_utils_pref(AddonPreferences):
     show_remove_mat = BoolProperty(
             name="Enable Remove all Materials",
             default=False,
-            description="Enable Remove all Materials \n"
-                        "for all Selected Objects \n \n"
-                        "Use with care - if you want to keep materials after \n"
-                        "closing \ reloading Blender Set Fake User for them",
+            description="Enable Remove all Materials for all Selected Objects\n\n"
+                        "Use with care - if you want to keep materials after\n"
+                        "closing or reloading Blender, Set Fake User for them",
             )
     show_mat_preview = BoolProperty(
             name="Enable Material Preview",
@@ -2034,7 +2020,7 @@ class VIEW3D_MT_material_utils_pref(AddonPreferences):
             )
     show_converters = BoolProperty(
             name="Enable Converters",
-            default=True,
+            default=False,
             description="Enable Material Converters",
             )
     set_preview_size = EnumProperty(
@@ -2056,13 +2042,12 @@ class VIEW3D_MT_material_utils_pref(AddonPreferences):
             name="Preview Menu Type",
             description="Set the the Preview menu type",
             items=(('LIST', "Classic",
-                    "Display as a Classic List like in Blender Propreties. \n \n"
-                    "Preview of Active Material not available"),
+                    "Display as a Classic List like in Blender Propreties.\n"
+                    "Preview of Active Material is not available"),
                    ('PREVIEW', "Preview Display",
-                    "Display as a preview of Thumbnails \n"
-                    "It can have some performance issues with \n"
-                    "scenes containing a lot of materials \n \n"
-                    "Preview of Active Material available")),
+                    "Display as a preview of Thumbnails\n"
+                    "It can have some performance issues with scenes containing a lot of materials\n"
+                    "Preview of Active Material is available")),
             default='PREVIEW',
             )
     set_experimental_type = EnumProperty(
@@ -2101,21 +2086,22 @@ class VIEW3D_MT_material_utils_pref(AddonPreferences):
         col.prop(self, "show_separators")
 
         boxie = box.box()
-        row = boxie.row()
-        row.prop(self, "show_mat_preview")
-        rowsy = row.split(align=True)
-        rowsy.enabled = True if self.show_mat_preview else False
-        rowsy.prop(self, "set_preview_type", expand=True)
-        rowsa = boxie.row(align=True)
-        rowsa.enabled = True if self.set_preview_type in {'PREVIEW'} else False
-        rowsa.prop(self, "set_preview_size", expand=True)
+        split = boxie.split(percentage=0.3)
+        split.prop(self, "show_mat_preview")
+        if self.show_mat_preview:
+            rowsy = split.row(align=True)
+            rowsy.enabled = True if self.show_mat_preview else False
+            rowsy.prop(self, "set_preview_type", expand=True)
+            rowsa = boxie.row(align=True)
+            rowsa.enabled = True if self.set_preview_type in {'PREVIEW'} else False
+            rowsa.prop(self, "set_preview_size", expand=True)
 
         boxif = box.box()
-        rowf = boxif.row()
-        rowf.prop(self, "show_converters")
-        rowsf = rowf.split()
-        rowsf.enabled = True if self.show_converters else False
-        rowsf.prop(self, "set_experimental_type", expand=True)
+        split = boxif.split(percentage=0.3)
+        split.prop(self, "show_converters")
+        if self.show_converters:
+            rowe = split.row(align=True)
+            rowe.prop(self, "set_experimental_type", expand=True)
 
 
 # utility functions:
@@ -2224,7 +2210,7 @@ def c_need_of_viewport_colors():
     return False
 
 
-# Draw Separator #
+# Draw Separator
 def use_separator(operator, context):
     # pass the preferences show_separators bool to enable/disable them
     pref = return_preferences()
@@ -2233,7 +2219,7 @@ def use_separator(operator, context):
         operator.layout.separator()
 
 
-# preferences utilities #
+# preferences utilities
 
 def return_preferences():
     return bpy.context.user_preferences.addons[__name__].preferences
@@ -2299,9 +2285,9 @@ def register():
     warning_messages_utils.MAT_SPEC_NAME = __name__
 
     # Register Scene Properties
-    bpy.types.Scene.mat_specials = bpy.props.PointerProperty(
-                                            type=material_specials_scene_props
-                                            )
+    bpy.types.Scene.mat_specials = PointerProperty(
+                                        type=material_specials_scene_props
+                                        )
 
     kc = bpy.context.window_manager.keyconfigs.addon
     if kc:
diff --git a/materials_utils/material_converter.py b/materials_utils/material_converter.py
index 86e6ada7..dfde5c50 100644
--- a/materials_utils/material_converter.py
+++ b/materials_utils/material_converter.py
@@ -1,18 +1,17 @@
 # -*- coding: utf-8 -*-
 
 import bpy
-import mathutils
 from mathutils import Vector
 from bpy.types import Operator
 from .warning_messages_utils import (
-            warning_messages,
-            c_is_cycles_addon_enabled,
-            c_data_has_materials,
-            collect_report,
-            )
+        warning_messages,
+        c_is_cycles_addon_enabled,
+        c_data_has_materials,
+        collect_report,
+        )
 
 # -----------------------------------------------------------------------------
-# Globals #
+# Globals
 
 nodesDictionary = None
 
@@ -39,7 +38,7 @@ textureNodeSizeY = 350
 
 
 # -----------------------------------------------------------------------------
-# Functions #
+# Functions
 
 def makeTextureNodeDict(cmat):
     global nodesDictionary
@@ -155,11 +154,11 @@ def replaceNode(oldNode, newNode):
     newNode.location = oldNode.location
     try:
         for link in oldNode.outputs['BSDF'].links:
-            links.new(newNode.outputs['BSDF'], link.to_socket)
+            link.new(newNode.outputs['BSDF'], link.to_socket)
         for link in oldNode.inputs['Color'].links:
-            links.new(newNode.inputs['Color'], link.from_socket)
+            link.new(newNode.inputs['Color'], link.from_socket)
         for link in oldNode.inputs['Normal'].links:
-            links.new(newNode.inputs['Normal'], link.from_socket)
+            link.new(newNode.inputs['Normal'], link.from_socket)
     except:
         collect_report("ERROR: Failure to replace node")
 
@@ -252,8 +251,10 @@ def createDiffuseNodes(cmat, texCoordNode, mainShader, materialOutput):
                     mixRgbNode.parent = diffuseFrame
                     addRGBMixNode(TreeNodes, textureSlot, mixRgbNode, texNode, latestNode,
                                   '{}'.format(groupName), textureIdx)
-                    mixRgbNode.location = Vector((max(texNode.location.x, latestNode.location.x),
-                                                 (texNode.location.y + latestNode.location.y) / 2)) + Vector((200, 0))
+                    mixRgbNode.location = Vector(
+                                    (max(texNode.location.x, latestNode.location.x),
+                                    (texNode.location.y + latestNode.location.y) / 2)) + Vector((200, 0)
+                                    )
                     latestNode = mixRgbNode
                 except:
                     continue
@@ -325,7 +326,8 @@ def createNormalNodes(cmat, texCoordNode, mainShader, materialOutput):
             tex_node_name = getattr(texNode.image, "name", "")
             collect_report("INFO: Generating Normal Nodes for: " + tex_node_name)
             texNode.parent = normalFrame
-            placeNode(texNode, -500 - ((texCount) * 200), currPosY, textureNodeSizeX, textureNodeSizeY, 0, textureIdx)
+            placeNode(texNode, -500 - ((texCount) * 200), currPosY,
+                      textureNodeSizeX, textureNodeSizeY, 0, textureIdx)
 
             # Add mapping node
             normalMapping = TreeNodes.nodes.new(MAPPING_NODE)
@@ -364,8 +366,10 @@ def createNormalNodes(cmat, texCoordNode, mainShader, materialOutput):
                     mixRgbNode.parent = normalFrame
                     addRGBMixNode(TreeNodes, textureSlot, mixRgbNode, texNode, latestNode,
                                   '{}'.format(groupName), textureIdx)
-                    mixRgbNode.location = Vector((max(texNode.location.x, latestNode.location.x),
-                                                 (texNode.location.y + latestNode.location.y) / 2)) + Vector((200, 0))
+                    mixRgbNode.location = Vector(
+                                            (max(texNode.location.x, latestNode.location.x),
+                                            (texNode.location.y + latestNode.location.y) / 2)) + Vector((200, 0)
+                                            )
                     latestNode = mixRgbNode
                 except:
                     continue
@@ -401,7 +405,8 @@ def createSpecularNodes(cmat, texCoordNode, mainShader, mainDiffuse, materialOut
             tex_node_name = getattr(texNode.image, "name", "")
             collect_report("INFO: Generating {} Nodes for: ".format(groupName) + tex_node_name)
             texNode.parent = specularFrame
-            placeNode(texNode, -500 - ((texCount) * 200), currPosY, textureNodeSizeX, textureNodeSizeY, 0, textureIdx)
+            placeNode(texNode, -500 - ((texCount) * 200),
+                      currPosY, textureNodeSizeX, textureNodeSizeY, 0, textureIdx)
 
             # Add mapping node
             specularMapping = TreeNodes.nodes.new(MAPPING_NODE)
@@ -439,8 +444,10 @@ def createSpecularNodes(cmat, texCoordNode, mainShader, mainDiffuse, materialOut
                     mixRgbNode.parent = specularFrame
                     addRGBMixNode(TreeNodes, textureSlot, mixRgbNode, texNode, latestNode,
                                   '{}'.format(groupName), textureIdx)
-                    mixRgbNode.location = Vector((max(texNode.location.x, latestNode.location.x),
-                                                 (texNode.location.y + latestNode.location.y) / 2)) + Vector((200, 0))
+                    mixRgbNode.location = Vector(
+                                            (max(texNode.location.x, latestNode.location.x),
+                                            (texNode.location.y + latestNode.location.y) / 2)) + Vector((200, 0)
+                                            )
                     latestNode = mixRgbNode
                 except:
                     continue
@@ -505,7 +512,8 @@ def createEmissionNodes(cmat, texCoordNode, mainShader, materialOutput):
             tex_node_name = getattr(texNode.image, "name", "")
             collect_report("INFO: Generating {} Nodes for: ".format(groupName) + tex_node_name)
             texNode.parent = emissionFrame
-            placeNode(texNode, -500 - ((texCount) * 200), currPosY, textureNodeSizeX, textureNodeSizeY, 0, textureIdx)
+            placeNode(texNode, -500 - ((texCount) * 200), currPosY,
+                      textureNodeSizeX, textureNodeSizeY, 0, textureIdx)
 
             # Add mapping node
             emissionMapping = TreeNodes.nodes.new(MAPPING_NODE)
@@ -544,8 +552,10 @@ def createEmissionNodes(cmat, texCoordNode, mainShader, materialOutput):
                     mixRgbNode.parent = emissionFrame
                     addRGBMixNode(TreeNodes, textureSlot, mixRgbNode, texNode, latestNode,
                                   '{}'.format(groupName), textureIdx)
-                    mixRgbNode.location = Vector((max(texNode.location.x, latestNode.location.x),
-                                                 (texNode.location.y + latestNode.location.y) / 2)) + Vector((200, 0))
+                    mixRgbNode.location = Vector(
+                                            (max(texNode.location.x, latestNode.location.x),
+                                            (texNode.location.y + latestNode.location.y) / 2)) + Vector((200, 0)
+                                            )
                     latestNode = mixRgbNode
                 except:
                     continue
@@ -604,9 +614,9 @@ def AutoNode(active=False, operator=None):
     if not materials:
         if operator:
             if active:
-                warning_messages(operator, 'CONV_NO_SEL_MAT')
+                warning_messages(operator, 'CONV_NO_SEL_MAT', override=True)
             else:
-                warning_messages(operator, 'CONV_NO_SC_MAT')
+                warning_messages(operator, 'CONV_NO_SC_MAT', override=True)
         return
 
     for cmat in materials:
@@ -649,7 +659,6 @@ def makeCyclesFromBI(cmat):
     cmat_mirror = cmat.raytrace_mirror.use
     cmat_mirror_fac = cmat.raytrace_mirror.reflect_factor
 
-    # --------------------------------------
     # Material Shaders
     # Diffuse nodes
     # --------------------------------------
@@ -727,17 +736,19 @@ def makeCyclesFromBI(cmat):
 
 
 # -----------------------------------------------------------------------------
-# Operator Classes #
+# Operator Classes
 
 class material_convert_all(Operator):
     bl_idname = "xps_tools.convert_to_cycles_all"
     bl_label = "Convert All Materials"
-    bl_description = "Convert All Materials to BI and Cycles Nodes"
+    bl_description = ("Convert All Materials to BI and Cycles Nodes\n"
+                      "Needs saving the .blend file first")
     bl_options = {'REGISTER', 'UNDO'}
 
     @classmethod
     def poll(cls, context):
-        return (c_is_cycles_addon_enabled() and c_data_has_materials())
+        return (bpy.data.filepath != "" and c_is_cycles_addon_enabled() and
+                c_data_has_materials())
 
     def execute(self, context):
         AutoNode(False, self)
@@ -747,14 +758,15 @@ class material_convert_all(Operator):
 class material_convert_selected(Operator):
     bl_idname = "xps_tools.convert_to_cycles_selected"
     bl_label = "Convert All Materials From Selected Objects"
-    bl_description = "Convert All Materials on Selected Objects to BI and Cycles Nodes"
+    bl_description = ("Convert All Materials on Selected Objects to BI and Cycles Nodes\n"
+                      "Needs saving the .blend file first")
     bl_options = {'REGISTER', 'UNDO'}
 
     @classmethod
     def poll(cls, context):
-        return (c_data_has_materials() and c_is_cycles_addon_enabled() and
-                bool(
-                    next((obj for obj in context.selected_objects if obj.type == 'MESH'),
+        return (bpy.data.filepath != "" and c_data_has_materials() and
+                c_is_cycles_addon_enabled() and
+                bool(next((obj for obj in context.selected_objects if obj.type == 'MESH'),
                          None)
                     )
                 )
@@ -773,5 +785,6 @@ def unregister():
     bpy.utils.unregister_module(__name__)
     pass
 
+
 if __name__ == "__main__":
     register()
diff --git a/materials_utils/materials_cycles_converter.py b/materials_utils/materials_cycles_converter.py
index 55c57ba7..c9dd994d 100644
--- a/materials_utils/materials_cycles_converter.py
+++ b/materials_utils/materials_cycles_converter.py
@@ -5,22 +5,22 @@
 import bpy
 from os import path as os_path
 from bpy.types import Operator
-from math import (log2,
-                  ceil,
-                  )
+from math import (
+        log2, ceil,
+        )
 from bpy.props import (
-            BoolProperty,
-            EnumProperty,
-            )
+        BoolProperty,
+        EnumProperty,
+        )
 from .warning_messages_utils import (
-            warning_messages,
-            c_is_cycles_addon_enabled,
-            c_data_has_materials,
-            collect_report,
-            )
+        warning_messages,
+        c_is_cycles_addon_enabled,
+        c_data_has_materials,
+        collect_report,
+        )
 
 # -----------------------------------------------------------------------------
-# Globals #
+# Globals
 
 # switch for operator's function called after AutoNodeInitiate
 CHECK_AUTONODE = False
@@ -37,7 +37,7 @@ PAINT_SC_COLOR = (0.80, 0.75, 0.54, 0.9)
 CLAY_GLOSSY = (0.38, 0.032, 0.023, 1)
 
 # -----------------------------------------------------------------------------
-# Functions #
+# Functions
 
 
 def AutoNodeSwitch(renderer="CYCLES", switch="OFF", operator=None):
@@ -130,8 +130,7 @@ def BakingText(tex, mode, tex_type=None):
     img = bpy.data.images.get("TMP_BAKING")
     img.file_format = ("JPEG" if not mode == "ALPHA" else "PNG")
 
-    # switch temporarly to 'IMAGE EDITOR'
-    # other approaches are not reliable
+    # switch temporarly to 'IMAGE EDITOR', other approaches are not reliable
     check_area = False
     store_area = bpy.context.area.type
     collect_report("INFO: Temporarly switching context to Image Editor")
@@ -211,7 +210,7 @@ def AutoNodeInitiate(active=False, operator=None):
         if sc.mat_specials.SET_FAKE_USER:
             SetFakeUserTex()
     else:
-        warning_messages(operator, 'DIR_PATH_CONVERT')
+        warning_messages(operator, 'DIR_PATH_CONVERT', override=True)
 
 
 def AutoNode(active=False, operator=None):
@@ -850,7 +849,7 @@ def create_mix_node(TreeNodes, links, nodes, loc, start, median_point, row, fram
 
 
 # -----------------------------------------------------------------------------
-# Operator Classes #
+# Operator Classes
 
 class mllock(Operator):
     bl_idname = "ml.lock"
@@ -877,12 +876,14 @@ class mllock(Operator):
 class mlrefresh(Operator):
     bl_idname = "ml.refresh"
     bl_label = "Convert All Materials"
-    bl_description = "Convert All Materials in the scene from non-nodes to Cycles"
+    bl_description = ("Convert All Materials in the scene from non-nodes to Cycles\n"
+                      "Needs saving the .blend file first")
     bl_options = {'REGISTER', 'UNDO'}
 
     @classmethod
     def poll(cls, context):
-        return (c_is_cycles_addon_enabled() and c_data_has_materials())
+        return (bpy.data.filepath != ""and c_is_cycles_addon_enabled() and
+                c_data_has_materials())
 
     def execute(self, context):
         AutoNodeInitiate(False, self)
@@ -909,13 +910,14 @@ class mlrefresh(Operator):
 class mlrefresh_active(Operator):
     bl_idname = "ml.refresh_active"
     bl_label = "Convert All Materials From Active Object"
-    bl_description = "Convert all Active Object's Materials from non-nodes to Cycles"
+    bl_description = ("Convert all Active Object's Materials from non-nodes to Cycles\n"
+                      "Needs saving the .blend file first")
     bl_options = {'REGISTER', 'UNDO'}
 
     @classmethod
     def poll(cls, context):
-        return (c_is_cycles_addon_enabled() and c_data_has_materials() and
-                context.active_object is not None)
+        return (bpy.data.filepath != "" and c_is_cycles_addon_enabled() and
+                c_data_has_materials() and context.active_object is not None)
 
     def execute(self, context):
         AutoNodeInitiate(True, self)
@@ -978,5 +980,6 @@ def unregister():
     bpy.utils.unregister_module(__name__)
     pass
 
+
 if __name__ == "__main__":
     register()
diff --git a/materials_utils/texture_rename.py b/materials_utils/texture_rename.py
index ddea43cc..ac728b70 100644
--- a/materials_utils/texture_rename.py
+++ b/materials_utils/texture_rename.py
@@ -3,21 +3,20 @@
 
 import bpy
 from bpy.types import (
-            Operator,
-            Panel,
-            )
+        Operator,
+        Panel,
+        )
 from bpy.props import StringProperty
 from .warning_messages_utils import (
-            warning_messages,
-            c_data_has_images,
-            )
+        warning_messages,
+        c_data_has_images,
+        )
 
 
 class TEXTURE_OT_patern_rename(Operator):
     bl_idname = "texture.patern_rename"
     bl_label = "Texture Renamer"
-    bl_description = ("Replace the Texture names pattern with \n"
-                      "the attached Image ones. \n"
+    bl_description = ("Replace the Texture names pattern with the attached Image ones\n"
                       "Works on all Textures (Including Brushes) \n \n"
                       "The First field - the name pattern to replace \n"
                       "The Second - searches for existing names \n")
@@ -108,5 +107,6 @@ def unregister():
     bpy.utils.unregister_module(__name__)
     pass
 
+
 if __name__ == "__main__":
     register()
diff --git a/materials_utils/warning_messages_utils.py b/materials_utils/warning_messages_utils.py
index 7a7ab0de..2e5f3b69 100644
--- a/materials_utils/warning_messages_utils.py
+++ b/materials_utils/warning_messages_utils.py
@@ -12,19 +12,22 @@ MAT_SPEC_NAME = "materials_specials"
 COLLECT_REPORT = []
 
 
-# Functions #
+# Functions
 
-def warning_messages(operator=None, warn='DEFAULT', object_name="", is_mat=None, fake=""):
+def warning_messages(operator=None, warn='DEFAULT', object_name="", is_mat=None,
+                     fake="", override=False):
     # Enter warning messages to the message dictionary
     # warn - if nothing passed falls back to DEFAULT
     # a list of strings can be passed and concatenated in obj_name too
     # is_mat a switch to change to materials or textures for obj_name('MAT','TEX', 'FILE', None)
     # fake - optional string that can be passed
     # MAX_COUNT - max members of an list to be displayed
+    # override - important messages that should be enabled, no matter the setting
 
     # pass the show_warnings bool to enable/disable them
     addon = bpy.context.user_preferences.addons[MAT_SPEC_NAME]
-    show_warn = (addon.preferences.show_warnings if addon else False)
+    get_warn = addon.preferences.show_warnings if addon else False
+    show_warn = get_warn if override is False else override
 
     if show_warn and operator:
         obj_name = ""
@@ -102,6 +105,7 @@ def warning_messages(operator=None, warn='DEFAULT', object_name="", is_mat=None,
             'DIR_PATH_A_ERROR': "ERROR: Directory not accessible",
             'DIR_PATH_W_OK': "Directory has writing privileges",
             'DIR_PATH_CONVERT': "Conversion Cancelled. Problem with chosen Directory, check System Console",
+            'DIR_PATH_EMPTY': "File Path is empty. Please save the .blend file first",
             'MAT_LINK_ERROR': "{}{}".format(obj_name, "not be renamed or set as Base(s)"),
             'MAT_LINK_NO_NAME': "No Base name given, No changes applied",
             'MOVE_SLOT_UP': "{}{}".format(obj_name, "been moved on top of the stack"),
@@ -122,6 +126,10 @@ def warning_messages(operator=None, warn='DEFAULT', object_name="", is_mat=None,
             print("\n** MATERIAL SPECIALS **: \n Full list for the Info message is: \n",
                   ", ".join(object_name), "\n")
 
+    # restore settings if overriden
+    if override:
+        addon.preferences.show_warnings = get_warn
+
 
 def collect_report(collection="", is_start=False, is_final=False):
     # collection passes a string for appending to COLLECT_REPORT global
@@ -146,11 +154,8 @@ def collect_report(collection="", is_start=False, is_final=False):
         COLLECT_REPORT = []
 
 
-# utility functions:
-
 def c_is_cycles_addon_enabled():
-    # checks if Cycles is enabled
-    # thanks to ideasman42
+    # checks if Cycles is enabled thanks to ideasman42
     return ('cycles' in bpy.context.user_preferences.addons.keys())