Draft: Added preference setting to use the new C++ dxf importer

src/Mod/Draft/Resources/ui/preferences-dxf.ui

@@ -61,6 +61,29 @@
       <property name="margin">
        <number>9</number>
       </property>
+      <item>
+       <layout class="QHBoxLayout" name="horizontalLayout_6">
+        <item>
+         <widget class="Gui::PrefCheckBox" name="checkBox_4">
+          <property name="toolTip">
+           <string>If this is checked, the old python importer is used, otherwise the new C++ one (faster, but not as many features yet)</string>
+          </property>
+          <property name="text">
+           <string>Use legacy python importer</string>
+          </property>
+          <property name="checked">
+           <bool>true</bool>
+          </property>
+          <property name="prefEntry" stdset="0">
+           <cstring>dxfUseLegacyImporter</cstring>
+          </property>
+          <property name="prefPath" stdset="0">
+           <cstring>Mod/Draft</cstring>
+          </property>
+         </widget>
+        </item>
+       </layout>
+      </item>
       <item>
        <layout class="QHBoxLayout" name="horizontalLayout_7">
         <item>

src/Mod/Draft/importDXF.py

@@ -1467,6 +1467,7 @@ def warn(dxfobject,num=None):
 def open(filename):
     "called when freecad opens a file."
     readPreferences()
+    if dxfUseLegacyImporter:
         if dxfReader:
             docname = os.path.splitext(os.path.basename(filename))[0]
             if isinstance(docname,unicode): 
@@ -1478,10 +1479,21 @@ def open(filename):
             return doc
         else:
             errorDXFLib(gui)
+    else:
+        docname = os.path.splitext(os.path.basename(filename))[0]
+        if isinstance(docname,unicode): 
+            import sys #workaround since newDocument currently can't handle unicode filenames
+            docname = docname.encode(sys.getfilesystemencoding())
+        doc = FreeCAD.newDocument(docname)
+        doc.Label = decodeName(docname)
+        FreeCAD.setActiveDocument(docname)
+        import DraftUtils
+        DraftUtils.readDXF(filename)
 
 def insert(filename,docname):
     "called when freecad imports a file"
     readPreferences()
+    if dxfUseLegacyImporter:
         if dxfReader:
             groupname = os.path.splitext(os.path.basename(filename))[0]
             try:
@@ -1496,6 +1508,10 @@ def insert(filename,docname):
                 importgroup.addObject(l)
         else:
             errorDXFLib(gui)
+    else:
+        FreeCAD.setActiveDocument(docname)
+        import DraftUtils
+        DraftUtils.readDXF(filename)
 
 def getShapes(filename):
     "reads a dxf file and returns a list of shapes from its contents"
@@ -1944,7 +1960,7 @@ def readPreferences():
     global dxfCreatePart, dxfCreateDraft, dxfCreateSketch, dxfDiscretizeCurves, dxfStarBlocks
     global dxfMakeBlocks, dxfJoin, dxfRenderPolylineWidth, dxfImportTexts, dxfImportLayouts
     global dxfImportPoints, dxfImportHatches, dxfUseStandardSize, dxfGetColors, dxfUseDraftVisGroups
-    global dxfFillMode, dxfBrightBackground, dxfDefaultColor
+    global dxfFillMode, dxfBrightBackground, dxfDefaultColor, dxfUseLegacyImporter
     dxfCreatePart = p.GetBool("dxfCreatePart",True)
     dxfCreateDraft = p.GetBool("dxfCreateDraft",False)
     dxfCreateSketch = p.GetBool("dxfCreateSketch",False)
@@ -1961,5 +1977,6 @@ def readPreferences():
     dxfGetColors = p.GetBool("dxfGetOriginalColors",False)
     dxfUseDraftVisGroups = p.GetBool("dxfUseDraftVisGroups",False)
     dxfFillMode = p.GetBool("fillmode",True)
+    dxfUseLegacyImporter = p.GetBool("dxfUseLegacyImporter",True)
     dxfBrightBackground = isBrightBackground()
     dxfDefaultColor = getColor()