2 files changed, 134 insertions, 0 deletions

diff --git a/source/blender/blenkernel/BKE_mesh.h b/source/blender/blenkernel/BKE_mesh.h
index edbf4da33ac..339d13b06b2 100644
--- a/source/blender/blenkernel/BKE_mesh.h
+++ b/source/blender/blenkernel/BKE_mesh.h
@@ -361,6 +361,13 @@ void BKE_mesh_poly_edgehash_insert(struct EdgeHash *ehash, const struct MPoly *m
 
 void BKE_mesh_do_versions_cd_flag_init(struct Mesh *mesh);
 
+
+void BKE_mesh_mselect_clear(struct Mesh *me);
+void BKE_mesh_mselect_validate(struct Mesh *me);
+int  BKE_mesh_mselect_find(struct Mesh *me, int index, int type);
+int  BKE_mesh_mselect_active_get(struct Mesh *me, int type);
+void BKE_mesh_mselect_active_set(struct Mesh *me, int index, int type);
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/source/blender/blenkernel/intern/mesh.c b/source/blender/blenkernel/intern/mesh.c
index 3bb2d6fdba4..0ef92ca75a3 100644
--- a/source/blender/blenkernel/intern/mesh.c
+++ b/source/blender/blenkernel/intern/mesh.c
@@ -3767,3 +3767,130 @@ void BKE_mesh_do_versions_cd_flag_init(Mesh *mesh)
 
 	}
 }
+
+
+/* -------------------------------------------------------------------- */
+/* MSelect functions (currently used in weight paint mode) */
+
+void BKE_mesh_mselect_clear(Mesh *me)
+{
+	MEM_freeN(me->mselect);
+	me->mselect = NULL;
+	me->totselect = 0;
+}
+
+void BKE_mesh_mselect_validate(Mesh *me)
+{
+	MSelect *mselect_src, *mselect_dst;
+	int i_src, i_dst;
+
+	if (me->totselect == 0)
+		return;
+
+	mselect_src = me->mselect;
+	mselect_dst = MEM_mallocN(sizeof(MSelect) * (me->totselect), "Mesh selection history");
+
+	for (i_src = 0, i_dst = 0; i_src < me->totselect; i_src++) {
+		int index = mselect_src[i_src].index;
+		switch (mselect_src[i_src].type) {
+			case ME_VSEL:
+			{
+				if (me->mvert[index].flag & SELECT) {
+					mselect_dst[i_dst] = mselect_src[i_src];
+					i_dst++;
+				}
+				break;
+			}
+			case ME_ESEL:
+			{
+				if (me->medge[index].flag & SELECT) {
+					mselect_dst[i_dst] = mselect_src[i_src];
+					i_dst++;
+				}
+				break;
+			}
+			case ME_FSEL:
+			{
+				if (me->mpoly[index].flag & SELECT) {
+					mselect_dst[i_dst] = mselect_src[i_src];
+					i_dst++;
+				}
+				break;
+			}
+			default:
+			{
+				BLI_assert(0);
+				break;
+			}
+		}
+	}
+
+	MEM_freeN(mselect_src);
+
+	if (i_dst == 0) {
+		MEM_freeN(mselect_dst);
+		mselect_dst = NULL;
+	}
+	else if (i_dst != me->totselect) {
+		mselect_dst = MEM_reallocN(mselect_dst, sizeof(MSelect) * i_dst);
+	}
+
+	me->totselect = i_dst;
+	me->mselect = mselect_dst;
+
+}
+
+/**
+ * Return the index within me->mselect, or -1
+ */
+int BKE_mesh_mselect_find(Mesh *me, int index, int type)
+{
+	int i;
+
+	BLI_assert(ELEM3(type, ME_VSEL, ME_ESEL, ME_FSEL));
+
+	for (i = 0; i < me->totselect; i++) {
+		if ((me->mselect[i].index == index) &&
+			(me->mselect[i].type == type))
+		{
+			return i;
+		}
+	}
+
+	return -1;
+}
+
+/**
+ * Return The index of the active element.
+ */
+int BKE_mesh_mselect_active_get(Mesh *me, int type)
+{
+	BLI_assert(ELEM3(type, ME_VSEL, ME_ESEL, ME_FSEL));
+
+	if (me->totselect) {
+		if (me->mselect[me->totselect - 1].type == type) {
+			return me->mselect[me->totselect - 1].index;
+		}
+	}
+	return -1;
+}
+
+void BKE_mesh_mselect_active_set(Mesh *me, int index, int type)
+{
+	const int msel_index = BKE_mesh_mselect_find(me, index, type);
+
+	if (msel_index == -1) {
+		/* add to the end */
+		me->mselect = MEM_reallocN(me->mselect, sizeof(MSelect) * (me->totselect + 1));
+		me->mselect[me->totselect].index = index;
+		me->mselect[me->totselect].type  = type;
+		me->totselect++;
+	}
+	else if (msel_index != me->totselect - 1) {
+		/* move to the end */
+		SWAP(MSelect, me->mselect[msel_index], me->mselect[me->totselect - 1]);
+	}
+
+	BLI_assert((me->mselect[me->totselect - 1].index == index) &&
+	           (me->mselect[me->totselect - 1].type  == type));
+}