Objects: add Volume object type, and prototypes for Hair and PointCloud

Only the volume object is exposed in the user interface. It is based on OpenVDB
internally. Drawing and rendering code will follow in another commit.
https://wiki.blender.org/wiki/Source/Objects/Volume
https://wiki.blender.org/wiki/Reference/Release_Notes/2.83/Volumes

Hair and PointCloud object types are hidden behind a WITH_NEW_OBJECT_TYPES
build option. These are unfinished, and included only to make it easier to
cooperate on development in the future and avoid tricky merges.
https://wiki.blender.org/wiki/Source/Objects/New_Object_Types

Ref T73201, T68981

Differential Revision: https://developer.blender.org/D6945

1 files changed, 168 insertions, 0 deletions

diff --git a/source/blender/blenkernel/BKE_volume.h b/source/blender/blenkernel/BKE_volume.h
new file mode 100644
index 00000000000..b9845397d84
--- /dev/null
+++ b/source/blender/blenkernel/BKE_volume.h
@@ -0,0 +1,168 @@
+/*
+ * ***** 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): Brecht Van Lommel.
+ *
+ * ***** END GPL LICENSE BLOCK *****
+ */
+
+#ifndef __BKE_VOLUME_H__
+#define __BKE_VOLUME_H__
+
+/** \file BKE_volume.h
+ *  \ingroup bke
+ *  \brief Volume datablock.
+ */
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+struct BoundBox;
+struct Depsgraph;
+struct Main;
+struct Object;
+struct Scene;
+struct Volume;
+struct VolumeGridVector;
+
+/* Module */
+
+void BKE_volumes_init(void);
+
+/* Datablock Management */
+
+void BKE_volume_init_grids(struct Volume *volume);
+void *BKE_volume_add(struct Main *bmain, const char *name);
+struct Volume *BKE_volume_copy(struct Main *bmain, const struct Volume *volume);
+
+struct BoundBox *BKE_volume_boundbox_get(struct Object *ob);
+
+bool BKE_volume_is_y_up(const struct Volume *volume);
+bool BKE_volume_is_points_only(const struct Volume *volume);
+
+/* Depsgraph */
+
+void BKE_volume_eval_geometry(struct Depsgraph *depsgraph, struct Volume *volume);
+void BKE_volume_data_update(struct Depsgraph *depsgraph,
+                            struct Scene *scene,
+                            struct Object *object);
+
+void BKE_volume_grids_backup_restore(struct Volume *volume,
+                                     struct VolumeGridVector *grids,
+                                     const char *filepath);
+
+/* Draw Cache */
+
+enum {
+  BKE_VOLUME_BATCH_DIRTY_ALL = 0,
+};
+
+void BKE_volume_batch_cache_dirty_tag(struct Volume *volume, int mode);
+void BKE_volume_batch_cache_free(struct Volume *volume);
+
+extern void (*BKE_volume_batch_cache_dirty_tag_cb)(struct Volume *volume, int mode);
+extern void (*BKE_volume_batch_cache_free_cb)(struct Volume *volume);
+
+/* Grids
+ *
+ * For volumes referencing a file, the list of grids and metadata must be
+ * loaded before it can be accessed. This happens on-demand, only when needed
+ * by the user interface, dependency graph or render engine. */
+
+typedef struct VolumeGrid VolumeGrid;
+
+bool BKE_volume_load(struct Volume *volume, struct Main *bmain);
+void BKE_volume_unload(struct Volume *volume);
+bool BKE_volume_is_loaded(const struct Volume *volume);
+
+int BKE_volume_num_grids(const struct Volume *volume);
+const char *BKE_volume_grids_error_msg(const struct Volume *volume);
+VolumeGrid *BKE_volume_grid_get(const struct Volume *volume, int grid_index);
+VolumeGrid *BKE_volume_grid_active_get(const struct Volume *volume);
+VolumeGrid *BKE_volume_grid_find(const struct Volume *volume, const char *name);
+
+/* Grid
+ *
+ * By default only grid metadata is loaded, for access to the tree and voxels
+ * BKE_volume_grid_load must be called first. */
+
+typedef enum VolumeGridType {
+  VOLUME_GRID_UNKNOWN = 0,
+  VOLUME_GRID_BOOLEAN,
+  VOLUME_GRID_FLOAT,
+  VOLUME_GRID_DOUBLE,
+  VOLUME_GRID_INT,
+  VOLUME_GRID_INT64,
+  VOLUME_GRID_MASK,
+  VOLUME_GRID_STRING,
+  VOLUME_GRID_VECTOR_FLOAT,
+  VOLUME_GRID_VECTOR_DOUBLE,
+  VOLUME_GRID_VECTOR_INT,
+  VOLUME_GRID_POINTS,
+} VolumeGridType;
+
+bool BKE_volume_grid_load(const struct Volume *volume, struct VolumeGrid *grid);
+void BKE_volume_grid_unload(const struct Volume *volume, struct VolumeGrid *grid);
+bool BKE_volume_grid_is_loaded(const struct VolumeGrid *grid);
+
+/* Metadata */
+const char *BKE_volume_grid_name(const struct VolumeGrid *grid);
+VolumeGridType BKE_volume_grid_type(const struct VolumeGrid *grid);
+int BKE_volume_grid_channels(const struct VolumeGrid *grid);
+void BKE_volume_grid_transform_matrix(const struct VolumeGrid *grid, float mat[4][4]);
+
+/* Bounds */
+bool BKE_volume_grid_bounds(const struct VolumeGrid *grid, float min[3], float max[3]);
+
+/* Volume Editing
+ *
+ * These are intended for modifiers to use on evaluated datablocks.
+ *
+ * new_for_eval creates a volume datablock with no grids or file path, but
+ * preserves other settings such as viewport display options.
+ *
+ * copy_for_eval creates a volume datablock preserving everything except the
+ * file path. Grids are shared with the source datablock, not copied. */
+
+struct Volume *BKE_volume_new_for_eval(const struct Volume *volume_src);
+struct Volume *BKE_volume_copy_for_eval(struct Volume *volume_src, bool reference);
+
+struct VolumeGrid *BKE_volume_grid_add(struct Volume *volume,
+                                       const char *name,
+                                       VolumeGridType type);
+void BKE_volume_grid_remove(struct Volume *volume, struct VolumeGrid *grid);
+
+#ifdef __cplusplus
+}
+#endif
+
+/* OpenVDB Grid Access
+ *
+ * Access to OpenVDB grid for C++. These will automatically load grids from
+ * file or copy shared grids to make them writeable. */
+
+#if defined(__cplusplus) && defined(WITH_OPENVDB)
+#  include <openvdb/openvdb.h>
+openvdb::GridBase::ConstPtr BKE_volume_grid_openvdb_for_metadata(const struct VolumeGrid *grid);
+openvdb::GridBase::ConstPtr BKE_volume_grid_openvdb_for_read(const struct Volume *volume,
+                                                             struct VolumeGrid *grid);
+openvdb::GridBase::Ptr BKE_volume_grid_openvdb_for_write(const struct Volume *volume,
+                                                         struct VolumeGrid *grid,
+                                                         const bool clear);
+#endif
+
+#endif