added Mesh.calc_tessface(), needed to update mesh tessface after bmesh edits.

also add py api BMDeformVert.clear()

doc/python_api/rst/include__bmesh.rst

@@ -75,6 +75,16 @@ its good practice to call :class:`bmesh.types.BMesh.free` which will remove all
 further access.
 
 
+EditMode Tessellation
+^^^^^^^^^^^^^^^^^^^^^
+
+When writing scripts that operate on editmode data you will normally want to re-calculate the tessellation after
+running the  script, this needs to be called explicitly.
+
+The BMesh its self does not store the triangulated faces, they are stored in the :class:`bpy.types.Mesh`,
+to refresh tessellation faces call :class:`bpy.types.Mesh.calc_tessface`.
+
+
 CustomData Access
 -----------------
 

source/blender/editors/include/ED_mesh.h

@@ -261,6 +261,7 @@ void ED_mesh_vertices_remove(struct Mesh *mesh, struct ReportList *reports, int
 
 void ED_mesh_transform(struct Mesh *me, float *mat);
 void ED_mesh_calc_normals(struct Mesh *me);
+void ED_mesh_calc_tessface(struct Mesh *mesh);
 void ED_mesh_material_link(struct Mesh *me, struct Material *ma);
 void ED_mesh_update(struct Mesh *mesh, struct bContext *C, int calc_edges, int calc_tessface);
 

source/blender/editors/mesh/mesh_data.c

@@ -1182,3 +1182,13 @@ void ED_mesh_calc_normals(Mesh *mesh)
 	                  NULL);
 #endif
 }
+
+void ED_mesh_calc_tessface(Mesh *mesh)
+{
+	if (mesh->edit_btmesh) {
+		BMEdit_RecalcTessellation(mesh->edit_btmesh);
+	}
+	else {
+		BKE_mesh_tessface_calc(mesh);
+	}
+}

source/blender/makesrna/intern/rna_mesh_api.c

@@ -65,6 +65,9 @@ void RNA_api_mesh(StructRNA *srna)
 	func = RNA_def_function(srna, "calc_normals", "ED_mesh_calc_normals");
 	RNA_def_function_ui_description(func, "Calculate vertex normals");
 
+	func = RNA_def_function(srna, "calc_tessface", "ED_mesh_calc_tessface");
+	RNA_def_function_ui_description(func, "Calculate face tessellation (supports editmode too)");
+
 	func = RNA_def_function(srna, "update", "ED_mesh_update");
 	RNA_def_boolean(func, "calc_edges", 0, "Calculate Edges", "Force recalculation of edges");
 	RNA_def_boolean(func, "calc_tessface", 0, "Calculate Tessellation", "Force recalculation of tessellation faces");

source/blender/python/bmesh/bmesh_py_types_meshdata.c

@@ -525,12 +525,26 @@ static PyObject *bpy_bmdeformvert_get(BPy_BMDeformVert *self, PyObject *args)
 	}
 }
 
+
+PyDoc_STRVAR(bpy_bmdeformvert_clear_doc,
+".. method:: clear()\n"
+"\n"
+"   Clears all weights.\n"
+);
+static PyObject *bpy_bmdeformvert_clear(BPy_BMDeformVert *self)
+{
+	defvert_clear(self->data);
+
+	Py_RETURN_NONE;
+}
+
 static struct PyMethodDef bpy_bmdeformvert_methods[] = {
     {"keys",    (PyCFunction)bpy_bmdeformvert_keys,    METH_NOARGS,  bpy_bmdeformvert_keys_doc},
     {"values",  (PyCFunction)bpy_bmdeformvert_values,  METH_NOARGS,  bpy_bmdeformvert_values_doc},
     {"items",   (PyCFunction)bpy_bmdeformvert_items,   METH_NOARGS,  bpy_bmdeformvert_items_doc},
     {"get",     (PyCFunction)bpy_bmdeformvert_get,     METH_VARARGS, bpy_bmdeformvert_get_doc},
-    /* BMESH_TODO */
+    /* BMESH_TODO pop, popitem, update */
+    {"clear",   (PyCFunction)bpy_bmdeformvert_clear,   METH_NOARGS,  bpy_bmdeformvert_clear_doc},
     {NULL, NULL, 0, NULL}
 };
 
@@ -586,3 +600,4 @@ void BPy_BM_init_types_meshdata(void)
 	bm_init_types_bmloopcol();
 	bm_init_types_bmdvert();
 }
+