Rigify: refactor feature sets to avoid modifying global path.

Instead of adding the feature set installation directory
to the global path, and thus inserting the modules into
the top level namespace, add an empty rigify.feature_sets
package and use __path__ to redirect the module loader
to read its sub-modules from the feature set directory.

Now feature set modules are effectively installed into
that package and loaded as 'rigify.feature_sets.foo'.

As an aside, clean up loading code to avoid weird path
manipulations, add more safety checks when installing sets,
and add a way for sets to expose a user-friendly name.

1 files changed, 29 insertions, 0 deletions

diff --git a/rigify/feature_sets/__init__.py b/rigify/feature_sets/__init__.py
new file mode 100644
index 00000000..e9981d52
--- /dev/null
+++ b/rigify/feature_sets/__init__.py
@@ -0,0 +1,29 @@
+#====================== BEGIN GPL LICENSE BLOCK ======================
+#
+#  This program is free software; you can redistribute it and/or
+#  modify it under the terms of the GNU General Public License
+#  as published by the Free Software Foundation; either version 2
+#  of the License, or (at your option) any later version.
+#
+#  This program is distributed in the hope that it will be useful,
+#  but WITHOUT ANY WARRANTY; without even the implied warranty of
+#  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+#  GNU General Public License for more details.
+#
+#  You should have received a copy of the GNU General Public License
+#  along with this program; if not, write to the Free Software Foundation,
+#  Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+#
+#======================= END GPL LICENSE BLOCK ========================
+
+# Redirect the module loader to the user scripts directory.
+
+# Thus feature set modules can be added to this package without
+# writing to the actual Rigify installation directory.
+
+def _install_path():
+    import bpy
+    import os
+    return os.path.join(bpy.utils.script_path_user(), 'rigify')
+
+__path__ = [ _install_path() ]