Merge pull request #1423 from danieldresser-ie/noVdbStats

VDBObject : Don't bake in automatic metadata when querying metadata

Author: johnhaddon

Changes

@@ -1,10 +1,16 @@
 10.5.x.x (relative to 10.5.15.1)
 ========
 
+Fixes
+-----
+
+- VDBObject : Fixed worldBound() result when bbox metadata not already present.
+
 API
 ---
 
 - SConstruct : Install "private" headers.
+- VDBObject : Marked metadata() as deprecated
 
 10.5.15.1 (relative to 10.5.15.0)
 =========

include/IECoreVDB/VDBObject.h

@@ -88,6 +88,12 @@ class IECOREVDB_API VDBObject : public IECoreScene::VisibleRenderable
 		Imath::Box3f bound() const override;
 		void render( IECoreScene::Renderer *renderer ) const override;
 
+		// \deprecated
+		// Not threadsafe ( it computes statistics if not present and stores them on the grids ).
+		// Instead, use the VDB api, for example:
+		// findGrid( name )->beginMeta() to iterate the metadata,
+		// or
+		// findGrid( name )->evalActiveVoxelBoundingBox() or activeVoxelCount() to compute statistics
 		IECore::CompoundObjectPtr metadata( const std::string &name );
 
 		//! Are the grids in this VDBObject unmodified from the vdb file in filename?

src/IECoreVDB/VDBObject.cpp

@@ -57,11 +57,23 @@ namespace
 template<typename T>
 Imath::Box<Imath::Vec3<T> > worldBound( const openvdb::GridBase *grid, float padding = 0.50f )
 {
-	openvdb::Vec3i min = grid->metaValue<openvdb::Vec3i>( grid->META_FILE_BBOX_MIN );
-	openvdb::Vec3i max = grid->metaValue<openvdb::Vec3i>( grid->META_FILE_BBOX_MAX );
+	openvdb::CoordBBox vdbBbox;
+	try
+	{
+		vdbBbox.min() = openvdb::Coord( grid->metaValue<openvdb::Vec3i>( grid->META_FILE_BBOX_MIN ) );
+		vdbBbox.max() = openvdb::Coord( grid->metaValue<openvdb::Vec3i>( grid->META_FILE_BBOX_MAX ) );
+	}
+	catch( ... )
+	{
+		// If we don't have metadata available, then hopefully it's because the vdb was freshly created and
+		// hasn't been saved to file yet, which should mean it's fully loaded, and we can call
+		// evalActiveVoxelBoundingBox.
+		// \todo : Can we guarantee that every VDB either is loaded, or has metadata?
+		vdbBbox = grid->evalActiveVoxelBoundingBox();
+	}
 
 	openvdb::Vec3d offset = openvdb::Vec3d( padding );
-	openvdb::BBoxd indexBounds = openvdb::BBoxd( min - offset, max + offset );
+	openvdb::BBoxd indexBounds = openvdb::BBoxd( vdbBbox.min() - offset, vdbBbox.max() + offset );
 	openvdb::BBoxd worldBounds = grid->transform().indexToWorld( indexBounds );
 	openvdb::Vec3d minBB = worldBounds.min();
 	openvdb::Vec3d maxBB = worldBounds.max();