Alembic: exporting MetaBalls as mesh

- Only basis balls are exported, as they represent the resulting mesh.
  As a result the mesh is written to Alembic using the name of the basis
  ball.
- MetaBalls are converted to a mesh on every frame, then an
  AbcMeshWriter is used to write that mesh to Alembic.

1 files changed, 61 insertions, 0 deletions

diff --git a/source/blender/alembic/intern/abc_mball.h b/source/blender/alembic/intern/abc_mball.h
new file mode 100644
index 00000000000..46b61151216
--- /dev/null
+++ b/source/blender/alembic/intern/abc_mball.h
@@ -0,0 +1,61 @@
+/*
+ * ***** 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.
+ *
+ * Contributor(s): Sybren A. Stüvel
+ *
+ * ***** END GPL LICENSE BLOCK *****
+ */
+
+#ifndef __ABC_MBALL_H__
+#define __ABC_MBALL_H__
+
+#include "abc_object.h"
+
+struct AbcMeshWriter;
+struct Main;
+struct MetaBall;
+struct Object;
+
+/* AbcMBallWriter converts the metaballs to meshes at every frame,
+ * and defers to a wrapped AbcMeshWriter to perform the writing
+ * to the Alembic file. Only the basis balls are exported, as this
+ * results in the entire shape as one mesh. */
+class AbcMBallWriter : public AbcObjectWriter {
+	AbcMeshWriter *m_mesh_writer;
+	Object *m_mesh_ob;
+	bool m_is_animated;
+	Main *m_bmain;
+public:
+	AbcMBallWriter(
+	        Main *bmain,
+	        Scene *scene,
+	        Object *ob,
+	        AbcTransformWriter *parent,
+	        uint32_t time_sampling,
+	        ExportSettings &settings);
+
+	~AbcMBallWriter();
+
+	static bool isBasisBall(Scene *scene, Object *ob);
+
+private:
+	virtual void do_write();
+	bool isAnimated() const;
+};
+
+
+#endif  /* __ABC_MBALL_H__ */