[openscad] add icon for mirror mesh feature

src/Mod/OpenSCAD/OpenSCADCommands.py

@@ -168,8 +168,12 @@ class MirrorMeshFeature:
             newobj=selobj.Document.addObject("Mesh::Feature",'mirror')
             newobj.Label='mirror_%s' % selobj.Object.Label
             msh=selobj.Object.Mesh
-            newobj.Mesh=OpenSCADUtils.mirror(msh)
-            selobj.Object.ViewObject.hide()
+            newmesh=OpenSCADUtils.mirror(msh)
+            if not newmesh:
+                selobj.Document.removeObject(newobj.Name)
+            else:
+                newobj.Mesh=newmesh
+                selobj.Object.ViewObject.hide()
         FreeCAD.ActiveDocument.recompute()
     def GetResources(self):
         return {'Pixmap'  : 'OpenSCAD_MirrorMeshFeature',

src/Mod/OpenSCAD/OpenSCADUtils.py

@@ -309,7 +309,7 @@ def mirror(msh):
         mi = callopenscadmeshstring('%s{%s}' % (param,''.join(poly)))
         mi.flipNormals()
         return mi
-    return msh
+    return None
 
 
 def angneg(d):

src/Mod/OpenSCAD/Resources/OpenSCAD.qrc

@@ -1,5 +1,5 @@
 <RCC>
-    <qresource>
+    <qresource prefix="/">
         <file>icons/preferences-openscad.svg</file>
         <file>icons/OpenSCAD_AddOpenSCADElement.svg</file>
         <file>icons/OpenSCAD_ColorCodeShape.svg</file>
@@ -50,5 +50,6 @@
         <file>translations/OpenSCAD_val-ES.qm</file>
         <file>translations/OpenSCAD_ar.qm</file>
         <file>translations/OpenSCAD_vi.qm</file>
+        <file>icons/OpenSCAD_MirrorMeshFeature.svg</file>
     </qresource>
 </RCC>