Basic Alembic support

All in all, this patch adds an Alembic importer, an Alembic exporter,
and a new CacheFile data block which, for now, wraps around an Alembic
archive. This data block is made available through a new modifier ("Mesh
Sequence Cache") as well as a new constraint ("Transform Cache") to
somewhat properly support respectively geometric and transformation data
streaming from alembic caches.

A more in-depth documentation is to be found on the wiki, as well as a
 guide to compile alembic: https://wiki.blender.org/index.php/
User:Kevindietrich/AlembicBasicIo.

Many thanks to everyone involved in this little project, and huge shout
out to "cgstrive" for the thorough testings with Maya, 3ds Max, Houdini
and Realflow as well as @fjuhec, @jensverwiebe and @jasperge for the
custom builds and compile fixes.

Reviewers: sergey, campbellbarton, mont29

Reviewed By: sergey, campbellbarton, mont29

Differential Revision: https://developer.blender.org/D2060

1 files changed, 22 insertions, 0 deletions

diff --git a/source/blender/makesdna/DNA_modifier_types.h b/source/blender/makesdna/DNA_modifier_types.h
index bbc8edf4344..0424dc98a25 100644
--- a/source/blender/makesdna/DNA_modifier_types.h
+++ b/source/blender/makesdna/DNA_modifier_types.h
@@ -85,6 +85,7 @@ typedef enum ModifierType {
 	eModifierType_DataTransfer      = 49,
 	eModifierType_NormalEdit        = 50,
 	eModifierType_CorrectiveSmooth  = 51,
+	eModifierType_MeshSequenceCache = 52,
 	NUM_MODIFIER_TYPES
 } ModifierType;
 
@@ -1541,4 +1542,25 @@ enum {
 	MOD_NORMALEDIT_MIX_MUL  = 3,
 };
 
+typedef struct MeshSeqCacheModifierData {
+	ModifierData modifier;
+
+	struct CacheFile *cache_file;
+	char object_path[1024];  /* 1024 = FILE_MAX */
+
+	char read_flag;
+	char pad[7];
+} MeshSeqCacheModifierData;
+
+/* MeshSeqCacheModifierData.read_flag */
+enum {
+	MOD_MESHSEQ_READ_VERT  = (1 << 0),
+	MOD_MESHSEQ_READ_POLY  = (1 << 1),
+	MOD_MESHSEQ_READ_UV    = (1 << 2),
+	MOD_MESHSEQ_READ_COLOR = (1 << 3),
+};
+
+#define MOD_MESHSEQ_READ_ALL \
+	(MOD_MESHSEQ_READ_VERT | MOD_MESHSEQ_READ_POLY | MOD_MESHSEQ_READ_UV | MOD_MESHSEQ_READ_COLOR)
+
 #endif  /* __DNA_MODIFIER_TYPES_H__ */