Alembic import: port DerivedMesh → Mesh

10 files changed, 133 insertions, 149 deletions

diff --git a/source/blender/alembic/ABC_alembic.h b/source/blender/alembic/ABC_alembic.h
index 70250310213..08136fc2f49 100644
--- a/source/blender/alembic/ABC_alembic.h
+++ b/source/blender/alembic/ABC_alembic.h
@@ -29,8 +29,8 @@ extern "C" {
 
 struct bContext;
 struct CacheReader;
-struct DerivedMesh;
 struct ListBase;
+struct Mesh;
 struct Object;
 struct Scene;
 
@@ -114,12 +114,13 @@ void ABC_get_transform(struct CacheReader *reader,
                        float time,
                        float scale);
 
-struct DerivedMesh *ABC_read_mesh(struct CacheReader *reader,
-                                  struct Object *ob,
-                                  struct DerivedMesh *dm,
-                                  const float time,
-                                  const char **err_str,
-                                  int flags);
+/* Either modifies current_mesh in-place or constructs a new mesh. */
+struct Mesh *ABC_read_mesh(struct CacheReader *reader,
+                           struct Object *ob,
+                           struct Mesh *current_mesh,
+                           const float time,
+                           const char **err_str,
+                           int flags);
 
 void CacheReader_incref(struct CacheReader *reader);
 void CacheReader_free(struct CacheReader *reader);
diff --git a/source/blender/alembic/intern/abc_curves.cc b/source/blender/alembic/intern/abc_curves.cc
index 41c1dacabc0..9c64fd0481e 100644
--- a/source/blender/alembic/intern/abc_curves.cc
+++ b/source/blender/alembic/intern/abc_curves.cc
@@ -37,8 +37,8 @@ extern "C" {
 
 #include "BLI_listbase.h"
 
-#include "BKE_cdderivedmesh.h"
 #include "BKE_curve.h"
+#include "BKE_mesh.h"
 #include "BKE_object.h"
 
 #include "ED_curve.h"
@@ -400,16 +400,16 @@ void read_curve_sample(Curve *cu, const ICurvesSchema &schema, const ISampleSele
 	}
 }
 
-/* NOTE: Alembic only stores data about control points, but the DerivedMesh
+/* NOTE: Alembic only stores data about control points, but the Mesh
  * passed from the cache modifier contains the displist, which has more data
  * than the control points, so to avoid corrupting the displist we modify the
- * object directly and create a new DerivedMesh from that. Also we might need to
+ * object directly and create a new Mesh from that. Also we might need to
  * create new or delete existing NURBS in the curve.
  */
-DerivedMesh *AbcCurveReader::read_derivedmesh(DerivedMesh * /*dm*/,
-                                              const ISampleSelector &sample_sel,
-                                              int /*read_flag*/,
-                                              const char ** /*err_str*/)
+Mesh *AbcCurveReader::read_mesh(Mesh * /*existing_mesh*/,
+                                const ISampleSelector &sample_sel,
+                                int /*read_flag*/,
+                                const char ** /*err_str*/)
 {
 	const ICurvesSchema::Sample sample = m_curves_schema.getValue(sample_sel);
 
@@ -450,5 +450,5 @@ DerivedMesh *AbcCurveReader::read_derivedmesh(DerivedMesh * /*dm*/,
 		}
 	}
 
-	return CDDM_from_curve(m_object);
+	return BKE_mesh_new_nomain_from_curve(m_object);
 }
diff --git a/source/blender/alembic/intern/abc_curves.h b/source/blender/alembic/intern/abc_curves.h
index 1e7180bbb1f..e2373381703 100644
--- a/source/blender/alembic/intern/abc_curves.h
+++ b/source/blender/alembic/intern/abc_curves.h
@@ -60,10 +60,10 @@ public:
 	                         const char **err_str) const;
 
 	void readObjectData(Main *bmain, const Alembic::Abc::ISampleSelector &sample_sel);
-	DerivedMesh *read_derivedmesh(DerivedMesh *dm,
-	                              const Alembic::Abc::ISampleSelector &sample_sel,
-	                              int read_flag,
-	                              const char **err_str);
+	struct Mesh *read_mesh(struct Mesh *existing_mesh,
+	                       const Alembic::Abc::ISampleSelector &sample_sel,
+	                       int read_flag,
+	                       const char **err_str);
 };
 
 /* ************************************************************************** */
diff --git a/source/blender/alembic/intern/abc_mesh.cc b/source/blender/alembic/intern/abc_mesh.cc
index d52d7f06048..03d70b4f56b 100644
--- a/source/blender/alembic/intern/abc_mesh.cc
+++ b/source/blender/alembic/intern/abc_mesh.cc
@@ -873,11 +873,11 @@ ABC_INLINE void read_normals_params(AbcMeshData &abc_data,
 	}
 }
 
-static bool check_smooth_poly_flag(DerivedMesh *dm)
+static bool check_smooth_poly_flag(Mesh *mesh)
 {
-	MPoly *mpolys = dm->getPolyArray(dm);
+	MPoly *mpolys = mesh->mpoly;
 
-	for (int i = 0, e = dm->getNumPolys(dm); i < e; ++i) {
+	for (int i = 0, e = mesh->totpoly; i < e; ++i) {
 		MPoly &poly = mpolys[i];
 
 		if ((poly.flag & ME_SMOOTH) != 0) {
@@ -888,11 +888,11 @@ static bool check_smooth_poly_flag(DerivedMesh *dm)
 	return false;
 }
 
-static void set_smooth_poly_flag(DerivedMesh *dm)
+static void set_smooth_poly_flag(Mesh *mesh)
 {
-	MPoly *mpolys = dm->getPolyArray(dm);
+	MPoly *mpolys = mesh->mpoly;
 
-	for (int i = 0, e = dm->getNumPolys(dm); i < e; ++i) {
+	for (int i = 0, e = mesh->totpoly; i < e; ++i) {
 		MPoly &poly = mpolys[i];
 		poly.flag |= ME_SMOOTH;
 	}
@@ -900,7 +900,7 @@ static void set_smooth_poly_flag(DerivedMesh *dm)
 
 static void *add_customdata_cb(void *user_data, const char *name, int data_type)
 {
-	DerivedMesh *dm = static_cast<DerivedMesh *>(user_data);
+	Mesh *mesh = static_cast<Mesh *>(user_data);
 	CustomDataType cd_data_type = static_cast<CustomDataType>(data_type);
 	void *cd_ptr;
 	CustomData *loopdata;
@@ -911,7 +911,7 @@ static void *add_customdata_cb(void *user_data, const char *name, int data_type)
 		return NULL;
 	}
 
-	loopdata = dm->getLoopDataLayout(dm);
+	loopdata = &mesh->ldata;
 	cd_ptr = CustomData_get_layer_named(loopdata, cd_data_type, name);
 	if (cd_ptr != NULL) {
 		/* layer already exists, so just return it. */
@@ -920,7 +920,7 @@ static void *add_customdata_cb(void *user_data, const char *name, int data_type)
 
 	/* create a new layer, taking care to construct the hopefully-soon-to-be-removed
 	 * CD_MTEXPOLY layer too, with the same name. */
-	numloops = dm->getNumLoops(dm);
+	numloops = mesh->totloop;
 	cd_ptr = CustomData_add_layer_named(loopdata, cd_data_type, CD_DEFAULT,
 	                                    NULL, numloops, name);
 	return cd_ptr;
@@ -986,17 +986,19 @@ static void read_mesh_sample(const std::string & iobject_full_name,
 	}
 }
 
-CDStreamConfig get_config(DerivedMesh *dm)
+CDStreamConfig get_config(Mesh *mesh)
 {
 	CDStreamConfig config;
 
-	config.user_data = dm;
-	config.mvert = dm->getVertArray(dm);
-	config.mloop = dm->getLoopArray(dm);
-	config.mpoly = dm->getPolyArray(dm);
-	config.totloop = dm->getNumLoops(dm);
-	config.totpoly = dm->getNumPolys(dm);
-	config.loopdata = dm->getLoopDataLayout(dm);
+	BLI_assert(mesh->mvert);
+
+	config.user_data = mesh;
+	config.mvert = mesh->mvert;
+	config.mloop = mesh->mloop;
+	config.mpoly = mesh->mpoly;
+	config.totloop = mesh->totloop;
+	config.totpoly = mesh->totpoly;
+	config.loopdata = &mesh->ldata;
 	config.add_customdata_cb = add_customdata_cb;
 
 	return config;
@@ -1027,14 +1029,8 @@ void AbcMeshReader::readObjectData(Main *bmain, const Alembic::Abc::ISampleSelec
 	m_object = BKE_object_add_only_object(bmain, OB_MESH, m_object_name.c_str());
 	m_object->data = mesh;
 
-	DerivedMesh *dm = CDDM_from_mesh(mesh);
-	DerivedMesh *ndm = this->read_derivedmesh(dm, sample_sel, MOD_MESHSEQ_READ_ALL, NULL);
-
-	if (ndm != dm) {
-		dm->release(dm);
-	}
-
-	DM_to_mesh(ndm, mesh, m_object, CD_MASK_MESH, true);
+	Mesh *read_mesh = this->read_mesh(mesh, sample_sel, MOD_MESHSEQ_READ_ALL, NULL);
+	BKE_mesh_nomain_to_mesh(read_mesh, mesh, m_object, CD_MASK_MESH, true);
 
 	if (m_settings->validate_meshes) {
 		BKE_mesh_validate(mesh, false, false);
@@ -1064,10 +1060,10 @@ bool AbcMeshReader::accepts_object_type(const Alembic::AbcCoreAbstract::ObjectHe
 	return true;
 }
 
-DerivedMesh *AbcMeshReader::read_derivedmesh(DerivedMesh *dm,
-                                             const ISampleSelector &sample_sel,
-                                             int read_flag,
-                                             const char **err_str)
+Mesh *AbcMeshReader::read_mesh(Mesh *existing_mesh,
+                               const ISampleSelector &sample_sel,
+                               int read_flag,
+                               const char **err_str)
 {
 	const IPolyMeshSchema::Sample sample = m_schema.getValue(sample_sel);
 
@@ -1075,22 +1071,22 @@ DerivedMesh *AbcMeshReader::read_derivedmesh(DerivedMesh *dm,
 	const Alembic::Abc::Int32ArraySamplePtr &face_indices = sample.getFaceIndices();
 	const Alembic::Abc::Int32ArraySamplePtr &face_counts = sample.getFaceCounts();
 
-	DerivedMesh *new_dm = NULL;
+	Mesh *new_mesh = NULL;
 
 	/* Only read point data when streaming meshes, unless we need to create new ones. */
 	ImportSettings settings;
 	settings.read_flag |= read_flag;
 
-	bool topology_changed =  positions->size() != dm->getNumVerts(dm) ||
-	                         face_counts->size() != dm->getNumPolys(dm) ||
-	                         face_indices->size() != dm->getNumLoops(dm);
+	bool topology_changed =  positions->size() != existing_mesh->totvert ||
+	                         face_counts->size() != existing_mesh->totpoly ||
+	                         face_indices->size() != existing_mesh->totloop;
 	if (topology_changed) {
-		new_dm = CDDM_from_template(dm,
-		                            positions->size(),
-		                            0,
-		                            0,
-		                            face_indices->size(),
-		                            face_counts->size());
+		new_mesh = BKE_mesh_new_nomain_from_template(existing_mesh,
+		                                             positions->size(),
+		                                             0,
+		                                             0,
+		                                             face_indices->size(),
+		                                             face_counts->size());
 
 		settings.read_flag |= MOD_MESHSEQ_READ_ALL;
 	}
@@ -1098,8 +1094,8 @@ DerivedMesh *AbcMeshReader::read_derivedmesh(DerivedMesh *dm,
 		/* If the face count changed (e.g. by triangulation), only read points.
 		 * This prevents crash from T49813.
 		 * TODO(kevin): perhaps find a better way to do this? */
-		if (face_counts->size() != dm->getNumPolys(dm) ||
-		    face_indices->size() != dm->getNumLoops(dm))
+		if (face_counts->size() != existing_mesh->totpoly ||
+		    face_indices->size() != existing_mesh->totloop)
 		{
 			settings.read_flag = MOD_MESHSEQ_READ_VERT;
 
@@ -1110,40 +1106,39 @@ DerivedMesh *AbcMeshReader::read_derivedmesh(DerivedMesh *dm,
 		}
 	}
 
-	CDStreamConfig config = get_config(new_dm ? new_dm : dm);
+	CDStreamConfig config = get_config(new_mesh ? new_mesh : existing_mesh);
 	config.time = sample_sel.getRequestedTime();
 
 	bool do_normals = false;
 	read_mesh_sample(m_iobject.getFullName(),
 	                 &settings, m_schema, sample_sel, config, do_normals);
 
-	if (new_dm) {
+	if (new_mesh) {
 		/* Check if we had ME_SMOOTH flag set to restore it. */
-		if (!do_normals && check_smooth_poly_flag(dm)) {
-			set_smooth_poly_flag(new_dm);
+		if (!do_normals && check_smooth_poly_flag(existing_mesh)) {
+			set_smooth_poly_flag(new_mesh);
 		}
 
-		CDDM_calc_normals(new_dm);
-		CDDM_calc_edges(new_dm);
+		BKE_mesh_calc_normals(new_mesh);
+		BKE_mesh_calc_edges(new_mesh, false, false);
 
 		/* Here we assume that the number of materials doesn't change, i.e. that
 		 * the material slots that were created when the object was loaded from
 		 * Alembic are still valid now. */
-		size_t num_polys = new_dm->getNumPolys(new_dm);
+		size_t num_polys = new_mesh->totpoly;
 		if (num_polys > 0) {
-			MPoly *dmpolies = new_dm->getPolyArray(new_dm);
 			std::map<std::string, int> mat_map;
-			assign_facesets_to_mpoly(sample_sel, 0, dmpolies, num_polys, mat_map);
+			assign_facesets_to_mpoly(sample_sel, 0, new_mesh->mpoly, num_polys, mat_map);
 		}
 
-		return new_dm;
+		return new_mesh;
 	}
 
 	if (do_normals) {
-		CDDM_calc_normals(dm);
+		BKE_mesh_calc_normals(existing_mesh);
 	}
 
-	return dm;
+	return existing_mesh;
 }
 
 void AbcMeshReader::assign_facesets_to_mpoly(
@@ -1305,14 +1300,8 @@ void AbcSubDReader::readObjectData(Main *bmain, const Alembic::Abc::ISampleSelec
 	m_object = BKE_object_add_only_object(bmain, OB_MESH, m_object_name.c_str());
 	m_object->data = mesh;
 
-	DerivedMesh *dm = CDDM_from_mesh(mesh);
-	DerivedMesh *ndm = this->read_derivedmesh(dm, sample_sel, MOD_MESHSEQ_READ_ALL, NULL);
-
-	if (ndm != dm) {
-		dm->release(dm);
-	}
-
-	DM_to_mesh(ndm, mesh, m_object, CD_MASK_MESH, true);
+	Mesh *read_mesh = this->read_mesh(mesh, sample_sel, MOD_MESHSEQ_READ_ALL, NULL);
+	BKE_mesh_nomain_to_mesh(read_mesh, mesh, m_object, CD_MASK_MESH, true);
 
 	const ISubDSchema::Sample sample = m_schema.getValue(sample_sel);
 	Int32ArraySamplePtr indices = sample.getCreaseIndices();
@@ -1344,10 +1333,10 @@ void AbcSubDReader::readObjectData(Main *bmain, const Alembic::Abc::ISampleSelec
 	}
 }
 
-DerivedMesh *AbcSubDReader::read_derivedmesh(DerivedMesh *dm,
-                                             const ISampleSelector &sample_sel,
-                                             int read_flag,
-                                             const char **err_str)
+Mesh *AbcSubDReader::read_mesh(Mesh *existing_mesh,
+                               const ISampleSelector &sample_sel,
+                               int read_flag,
+                               const char **err_str)
 {
 	const ISubDSchema::Sample sample = m_schema.getValue(sample_sel);
 
@@ -1355,18 +1344,18 @@ DerivedMesh *AbcSubDReader::read_derivedmesh(DerivedMesh *dm,
 	const Alembic::Abc::Int32ArraySamplePtr &face_indices = sample.getFaceIndices();
 	const Alembic::Abc::Int32ArraySamplePtr &face_counts = sample.getFaceCounts();
 
-	DerivedMesh *new_dm = NULL;
+	Mesh *new_mesh = NULL;
 
 	ImportSettings settings;
 	settings.read_flag |= read_flag;
 
-	if (dm->getNumVerts(dm) != positions->size()) {
-		new_dm = CDDM_from_template(dm,
-		                            positions->size(),
-		                            0,
-		                            0,
-		                            face_indices->size(),
-		                            face_counts->size());
+	if (existing_mesh->totvert != positions->size()) {
+		new_mesh = BKE_mesh_new_nomain_from_template(existing_mesh,
+		                                           positions->size(),
+		                                           0,
+		                                           0,
+		                                           face_indices->size(),
+		                                           face_counts->size());
 
 		settings.read_flag |= MOD_MESHSEQ_READ_ALL;
 	}
@@ -1374,8 +1363,8 @@ DerivedMesh *AbcSubDReader::read_derivedmesh(DerivedMesh *dm,
 		/* If the face count changed (e.g. by triangulation), only read points.
 		 * This prevents crash from T49813.
 		 * TODO(kevin): perhaps find a better way to do this? */
-		if (face_counts->size() != dm->getNumPolys(dm) ||
-		    face_indices->size() != dm->getNumLoops(dm))
+		if (face_counts->size() != existing_mesh->totpoly ||
+		    face_indices->size() != existing_mesh->totpoly)
 		{
 			settings.read_flag = MOD_MESHSEQ_READ_VERT;
 
@@ -1387,22 +1376,22 @@ DerivedMesh *AbcSubDReader::read_derivedmesh(DerivedMesh *dm,
 	}
 
 	/* Only read point data when streaming meshes, unless we need to create new ones. */
-	CDStreamConfig config = get_config(new_dm ? new_dm : dm);
+	CDStreamConfig config = get_config(new_mesh ? new_mesh : existing_mesh);
 	config.time = sample_sel.getRequestedTime();
 	read_subd_sample(m_iobject.getFullName(),
 	                 &settings, m_schema, sample_sel, config);
 
-	if (new_dm) {
+	if (new_mesh) {
 		/* Check if we had ME_SMOOTH flag set to restore it. */
-		if (check_smooth_poly_flag(dm)) {
-			set_smooth_poly_flag(new_dm);
+		if (check_smooth_poly_flag(existing_mesh)) {
+			set_smooth_poly_flag(new_mesh);
 		}
 
-		CDDM_calc_normals(new_dm);
-		CDDM_calc_edges(new_dm);
+		BKE_mesh_calc_normals(new_mesh);
+		BKE_mesh_calc_edges(new_mesh, false, false);
 
-		return new_dm;
+		return new_mesh;
 	}
 
-	return dm;
+	return existing_mesh;
 }
diff --git a/source/blender/alembic/intern/abc_mesh.h b/source/blender/alembic/intern/abc_mesh.h
index c57123cda4c..455d263c689 100644
--- a/source/blender/alembic/intern/abc_mesh.h
+++ b/source/blender/alembic/intern/abc_mesh.h
@@ -106,10 +106,10 @@ public:
 	                       const char **err_str) const;
 	void readObjectData(Main *bmain, const Alembic::Abc::ISampleSelector &sample_sel);
 
-	DerivedMesh *read_derivedmesh(DerivedMesh *dm,
-	                              const Alembic::Abc::ISampleSelector &sample_sel,
-	                              int read_flag,
-	                              const char **err_str);
+	struct Mesh *read_mesh(struct Mesh *existing_mesh,
+	                       const Alembic::Abc::ISampleSelector &sample_sel,
+	                       int read_flag,
+	                       const char **err_str);
 
 private:
 	void readFaceSetsSample(Main *bmain, Mesh *mesh, size_t poly_start,
@@ -136,10 +136,10 @@ public:
 	                         const Object *const ob,
 	                         const char **err_str) const;
 	void readObjectData(Main *bmain, const Alembic::Abc::ISampleSelector &sample_sel);
-	DerivedMesh *read_derivedmesh(DerivedMesh *dm,
-	                              const Alembic::Abc::ISampleSelector &sample_sel,
-	                              int read_flag,
-	                              const char **err_str);
+	struct Mesh *read_mesh(struct Mesh *existing_mesh,
+	                       const Alembic::Abc::ISampleSelector &sample_sel,
+	                       int read_flag,
+	                       const char **err_str);
 };
 
 /* ************************************************************************** */
@@ -148,6 +148,6 @@ void read_mverts(MVert *mverts,
                  const Alembic::AbcGeom::P3fArraySamplePtr &positions,
                  const Alembic::AbcGeom::N3fArraySamplePtr &normals);
 
-CDStreamConfig get_config(DerivedMesh *dm);
+CDStreamConfig get_config(struct Mesh *mesh);
 
 #endif  /* __ABC_MESH_H__ */
diff --git a/source/blender/alembic/intern/abc_object.cc b/source/blender/alembic/intern/abc_object.cc
index 85bda9aa8eb..0f02300eae3 100644
--- a/source/blender/alembic/intern/abc_object.cc
+++ b/source/blender/alembic/intern/abc_object.cc
@@ -248,12 +248,12 @@ Imath::M44d get_matrix(const IXformSchema &schema, const float time)
 	return s0.getMatrix();
 }
 
-DerivedMesh *AbcObjectReader::read_derivedmesh(DerivedMesh *dm,
-                                               const Alembic::Abc::ISampleSelector &UNUSED(sample_sel),
-                                               int UNUSED(read_flag),
-                                               const char **UNUSED(err_str))
+struct Mesh *AbcObjectReader::read_mesh(struct Mesh *existing_mesh,
+                                        const Alembic::Abc::ISampleSelector &UNUSED(sample_sel),
+                                        int UNUSED(read_flag),
+                                        const char **UNUSED(err_str))
 {
-	return dm;
+	return existing_mesh;
 }
 
 void AbcObjectReader::setupObjectTransform(const float time)
diff --git a/source/blender/alembic/intern/abc_object.h b/source/blender/alembic/intern/abc_object.h
index d41088bdcad..809efd63d24 100644
--- a/source/blender/alembic/intern/abc_object.h
+++ b/source/blender/alembic/intern/abc_object.h
@@ -124,7 +124,7 @@ static bool has_animations(Schema &schema, ImportSettings *settings)
 
 /* ************************************************************************** */
 
-struct DerivedMesh;
+struct Mesh;
 
 using Alembic::AbcCoreAbstract::chrono_t;
 
@@ -180,10 +180,10 @@ public:
 
 	virtual void readObjectData(Main *bmain, const Alembic::Abc::ISampleSelector &sample_sel) = 0;
 
-	virtual DerivedMesh *read_derivedmesh(DerivedMesh *dm,
-	                                      const Alembic::Abc::ISampleSelector &sample_sel,
-	                                      int read_flag,
-	                                      const char **err_str);
+	virtual struct Mesh *read_mesh(struct Mesh *mesh,
+	                               const Alembic::Abc::ISampleSelector &sample_sel,
+	                               int read_flag,
+	                               const char **err_str);
 
 	/** Reads the object matrix and sets up an object transform if animated. */
 	void setupObjectTransform(const float time);
diff --git a/source/blender/alembic/intern/abc_points.cc b/source/blender/alembic/intern/abc_points.cc
index 6f52ccec4a7..c0d10ea4645 100644
--- a/source/blender/alembic/intern/abc_points.cc
+++ b/source/blender/alembic/intern/abc_points.cc
@@ -173,15 +173,9 @@ bool AbcPointsReader::accepts_object_type(const Alembic::AbcCoreAbstract::Object
 void AbcPointsReader::readObjectData(Main *bmain, const Alembic::Abc::ISampleSelector &sample_sel)
 {
 	Mesh *mesh = BKE_mesh_add(bmain, m_data_name.c_str());
+	Mesh *read_mesh = this->read_mesh(mesh, sample_sel, 0, NULL);
 
-	DerivedMesh *dm = CDDM_from_mesh(mesh);
-	DerivedMesh *ndm = this->read_derivedmesh(dm, sample_sel, 0, NULL);
-
-	if (ndm != dm) {
-		dm->release(dm);
-	}
-
-	DM_to_mesh(ndm, mesh, m_object, CD_MASK_MESH, true);
+	BKE_mesh_nomain_to_mesh(read_mesh, mesh, m_object, CD_MASK_MESH, true);
 
 	if (m_settings->validate_meshes) {
 		BKE_mesh_validate(mesh, false, false);
@@ -218,23 +212,23 @@ void read_points_sample(const IPointsSchema &schema,
 	read_mverts(config.mvert, positions, vnormals);
 }
 
-DerivedMesh *AbcPointsReader::read_derivedmesh(DerivedMesh *dm,
-                                               const ISampleSelector &sample_sel,
-                                               int /*read_flag*/,
-                                               const char ** /*err_str*/)
+struct Mesh *AbcPointsReader::read_mesh(struct Mesh *existing_mesh,
+                                        const ISampleSelector &sample_sel,
+                                        int /*read_flag*/,
+                                        const char ** /*err_str*/)
 {
 	const IPointsSchema::Sample sample = m_schema.getValue(sample_sel);
 
 	const P3fArraySamplePtr &positions = sample.getPositions();
 
-	DerivedMesh *new_dm = NULL;
+	Mesh *new_mesh = NULL;
 
-	if (dm->getNumVerts(dm) != positions->size()) {
-		new_dm = CDDM_new(positions->size(), 0, 0, 0, 0);
+	if (existing_mesh->totvert != positions->size()) {
+		new_mesh = BKE_mesh_new_nomain(positions->size(), 0, 0, 0, 0);
 	}
 
-	CDStreamConfig config = get_config(new_dm ? new_dm : dm);
+	CDStreamConfig config = get_config(new_mesh ? new_mesh : existing_mesh);
 	read_points_sample(m_schema, sample_sel, config);
 
-	return new_dm ? new_dm : dm;
+	return new_mesh ? new_mesh : existing_mesh;
 }
diff --git a/source/blender/alembic/intern/abc_points.h b/source/blender/alembic/intern/abc_points.h
index 1ac8792ede1..0c7924d9b9a 100644
--- a/source/blender/alembic/intern/abc_points.h
+++ b/source/blender/alembic/intern/abc_points.h
@@ -65,10 +65,10 @@ public:
 
 	void readObjectData(Main *bmain, const Alembic::Abc::ISampleSelector &sample_sel);
 
-	DerivedMesh *read_derivedmesh(DerivedMesh *dm,
-	                              const Alembic::Abc::ISampleSelector &sample_sel,
-	                              int read_flag,
-	                              const char **err_str);
+	struct Mesh *read_mesh(struct Mesh *existing_mesh,
+	                       const Alembic::Abc::ISampleSelector &sample_sel,
+	                       int read_flag,
+	                       const char **err_str);
 };
 
 void read_points_sample(const Alembic::AbcGeom::IPointsSchema &schema,
diff --git a/source/blender/alembic/intern/alembic_capi.cc b/source/blender/alembic/intern/alembic_capi.cc
index 1a6990a1de8..a32eabf2470 100644
--- a/source/blender/alembic/intern/alembic_capi.cc
+++ b/source/blender/alembic/intern/alembic_capi.cc
@@ -960,12 +960,12 @@ void ABC_get_transform(CacheReader *reader, float r_mat[4][4], float time, float
 
 /* ************************************************************************** */
 
-DerivedMesh *ABC_read_mesh(CacheReader *reader,
-                           Object *ob,
-                           DerivedMesh *dm,
-                           const float time,
-                           const char **err_str,
-                           int read_flag)
+Mesh *ABC_read_mesh(CacheReader *reader,
+                    Object *ob,
+                    Mesh *existing_mesh,
+                    const float time,
+                    const char **err_str,
+                    int read_flag)
 {
 	AbcObjectReader *abc_reader = reinterpret_cast<AbcObjectReader *>(reader);
 	IObject iobject = abc_reader->iobject();
@@ -984,7 +984,7 @@ DerivedMesh *ABC_read_mesh(CacheReader *reader,
 	/* kFloorIndex is used to be compatible with non-interpolating
 	 * properties; they use the floor. */
 	ISampleSelector sample_sel(time, ISampleSelector::kFloorIndex);
-	return abc_reader->read_derivedmesh(dm, sample_sel, read_flag, err_str);
+	return abc_reader->read_mesh(existing_mesh, sample_sel, read_flag, err_str);
 }
 
 /* ************************************************************************** */