1 files changed, 69 insertions, 0 deletions
diff --git a/source/blender/bmesh/intern/bmesh_mesh_partial_update.h b/source/blender/bmesh/intern/bmesh_mesh_partial_update.h
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+++ b/source/blender/bmesh/intern/bmesh_mesh_partial_update.h
@@ -0,0 +1,69 @@
+/*
+ * 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.
+ */
+
+#pragma once
+
+/** \file
+ * \ingroup bmesh
+ */
+
+#include "BLI_compiler_attrs.h"
+
+/**
+ * Parameters used to determine which kinds of data needs to be generated.
+ */
+typedef struct BMPartialUpdate_Params {
+  bool do_normals;
+  bool do_tessellate;
+} BMPartialUpdate_Params;
+
+/**
+ * Cached data to speed up partial updates.
+ *
+ * Hints:
+ *
+ * - Avoid creating this data for single updates,
+ *   it should be created and reused across multiple updates to gain a significant benefit
+ *   (while transforming geometry for example).
+ *
+ * - Partial normal updates use face & loop indices,
+ *   setting them to dirty values between updates will slow down normal recalculation.
+ */
+typedef struct BMPartialUpdate {
+  BMVert **verts;
+  BMEdge **edges;
+  BMFace **faces;
+  int verts_len, verts_len_alloc;
+  int edges_len, edges_len_alloc;
+  int faces_len, faces_len_alloc;
+  /**
+   * Faces at the end of `faces` that don't need to have the normals recalculated
+   * but must be included when waiting the vertex normals.
+   */
+  int faces_len_normal_calc_accumulate;
+
+  /** Store the parameters used in creation so invalid use can be asserted. */
+  BMPartialUpdate_Params params;
+} BMPartialUpdate;
+
+BMPartialUpdate *BM_mesh_partial_create_from_verts(BMesh *bm,
+                                                   const BMPartialUpdate_Params *params,
+                                                   const int verts_len,
+                                                   bool (*filter_fn)(BMVert *, void *user_data),
+                                                   void *user_data)
+    ATTR_NONNULL(1, 2, 4) ATTR_WARN_UNUSED_RESULT;
+
+void BM_mesh_partial_destroy(BMPartialUpdate *bmpinfo) ATTR_NONNULL(1);