Userpreferences Panel (for the 3DView)

This is an attempt to improve the User preferences panel for the 3DView. I made 2 changes:

- I reordered the sequence of properties by grouping them into more logical groups as it made sense to me. Please indicate where to rearrange the order if necessary.

- Then i added some changes in the code to get the groups better arranged visually. I am pretty sure that this can be done much better, more clever, more generic, whatever. This is just what i could figure out on my own so far.

Reviewers: aligorith, sergey, gaiaclary

Subscribers: sergey

Projects: #user_interface

Maniphest Tasks: T47295

Differential Revision: https://developer.blender.org/D1757

release/scripts/startup/bl_ui/space_userpref.py

@@ -559,8 +559,33 @@ class USERPREF_PT_theme(Panel):
     bl_region_type = 'WINDOW'
     bl_options = {'HIDE_HEADER'}
 
+    # not essential, hard-coded UI delimiters for the theme layout
+    ui_delimiters = {
+        'VIEW_3D': {
+            "text_grease_pencil",
+            "text_keyframe",
+            "speaker",
+            "freestyle_face_mark",
+            "split_normal",
+            "bone_solid",
+            "paint_curve_pivot",
+            },
+        'GRAPH_EDITOR': {
+            "handle_vertex_select",
+            },
+        'IMAGE_EDITOR': {
+            "paint_curve_pivot",
+            },
+        'NODE_EDITOR': {
+            "layout_node",
+            },
+        'CLIP_EDITOR': {
+            "handle_vertex_select",
+            }
+        }
+
     @staticmethod
-    def _theme_generic(split, themedata):
+    def _theme_generic(split, themedata, theme_area):
 
         col = split.column()
 
@@ -587,13 +612,30 @@ class USERPREF_PT_theme(Panel):
 
                 props_type.setdefault((prop.type, prop.subtype), []).append(prop)
 
+            th_delimiters = USERPREF_PT_theme.ui_delimiters.get(theme_area)
             for props_type, props_ls in sorted(props_type.items()):
                 if props_type[0] == 'POINTER':
                     for i, prop in enumerate(props_ls):
                         theme_generic_recurse(getattr(data, prop.identifier))
                 else:
-                    for i, prop in enumerate(props_ls):
-                        colsub_pair[i % 2].row().prop(data, prop.identifier)
+                    if th_delimiters is None:
+                        # simple, no delimiters
+                        for i, prop in enumerate(props_ls):
+                            colsub_pair[i % 2].row().prop(data, prop.identifier)
+                    else:
+                        # add hard coded delimiters
+                        i = 0
+                        for prop in props_ls:
+                            colsub = colsub_pair[i]
+                            colsub.row().prop(data, prop.identifier)
+                            i = (i + 1) % 2
+                            if prop.identifier in th_delimiters:
+                                if i:
+                                    colsub = colsub_pair[1]
+                                    colsub.row().label("")
+                                colsub_pair[0].row().label("")
+                                colsub_pair[1].row().label("")
+                                i = 0
 
         theme_generic_recurse(themedata)
 
@@ -864,7 +906,7 @@ class USERPREF_PT_theme(Panel):
             col.label(text="Widget Label:")
             self._ui_font_style(col, style.widget_label)
         else:
-            self._theme_generic(split, getattr(theme, theme.theme_area.lower()))
+            self._theme_generic(split, getattr(theme, theme.theme_area.lower()), theme.theme_area)
 
 
 class USERPREF_PT_file(Panel):