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, 26 insertions, 0 deletions

diff --git a/source/blender/makesrna/intern/rna_constraint.c b/source/blender/makesrna/intern/rna_constraint.c
index 98560bf3452..db3f76f3cfc 100644
--- a/source/blender/makesrna/intern/rna_constraint.c
+++ b/source/blender/makesrna/intern/rna_constraint.c
@@ -72,6 +72,8 @@ EnumPropertyItem rna_enum_constraint_type_items[] = {
 	                            "Compensate for scaling one axis by applying suitable scaling to the other two axes"},
 	{CONSTRAINT_TYPE_TRANSFORM, "TRANSFORM", ICON_CONSTRAINT_DATA, "Transformation", 
 	                            "Use one transform property from target to control another (or same) property on owner"},
+	{CONSTRAINT_TYPE_TRANSFORM_CACHE, "TRANSFORM_CACHE", ICON_CONSTRAINT_DATA, "Transform Cache",
+	                            "Look up the transformation matrix from an external file"},
 	{0, "", 0, N_("Tracking"), ""},
 	{CONSTRAINT_TYPE_CLAMPTO,   "CLAMP_TO", ICON_CONSTRAINT_DATA, "Clamp To", 
 	                            "Restrict movements to lie along a curve by remapping location along curve's longest axis"},
@@ -214,6 +216,8 @@ static StructRNA *rna_ConstraintType_refine(struct PointerRNA *ptr)
 			return &RNA_CameraSolverConstraint;
 		case CONSTRAINT_TYPE_OBJECTSOLVER:
 			return &RNA_ObjectSolverConstraint;
+		case CONSTRAINT_TYPE_TRANSFORM_CACHE:
+			return &RNA_TransformCacheConstraint;
 		default:
 			return &RNA_UnknownType;
 	}
@@ -2571,6 +2575,27 @@ static void rna_def_constraint_object_solver(BlenderRNA *brna)
 	                               "rna_Constraint_cameraObject_poll");
 }
 
+static void rna_def_constraint_transform_cache(BlenderRNA *brna)
+{
+	StructRNA *srna;
+	PropertyRNA *prop;
+
+	srna = RNA_def_struct(brna, "TransformCacheConstraint", "Constraint");
+	RNA_def_struct_ui_text(srna, "Transform Cache Constraint", "Look up transformation from an external file");
+	RNA_def_struct_sdna_from(srna, "bTransformCacheConstraint", "data");
+
+	prop = RNA_def_property(srna, "cache_file", PROP_POINTER, PROP_NONE);
+	RNA_def_property_pointer_sdna(prop, NULL, "cache_file");
+	RNA_def_property_struct_type(prop, "CacheFile");
+	RNA_def_property_ui_text(prop, "Cache File", "");
+	RNA_def_property_flag(prop, PROP_EDITABLE | PROP_ID_SELF_CHECK);
+	RNA_def_property_update(prop, 0, "rna_Constraint_dependency_update");
+
+	prop = RNA_def_property(srna, "object_path", PROP_STRING, PROP_NONE);
+	RNA_def_property_ui_text(prop, "Object Path", "Path to the object in the Alembic archive used to lookup the transform matrix");
+	RNA_def_property_update(prop, 0, "rna_Constraint_update");
+}
+
 /* base struct for constraints */
 void RNA_def_constraint(BlenderRNA *brna)
 {
@@ -2687,6 +2712,7 @@ void RNA_def_constraint(BlenderRNA *brna)
 	rna_def_constraint_follow_track(brna);
 	rna_def_constraint_camera_solver(brna);
 	rna_def_constraint_object_solver(brna);
+	rna_def_constraint_transform_cache(brna);
 }
 
 #endif