Deborah R. Fowler
Alembic Files
Posted Feb 8 2015
Alembic - Open Interchange Format for Computer Graphics initially was developed in 2010 by Sony Pictures Imageworks and ILM. This interchange file format is used for geometry and animation.
Houdini supports demand-loading Alembic data (display without storing in memory). Note that you can set alembic nodes to view bounding boxes or point clouds instead of geometry. More information in Sidefx documentation.
Alembic file format (extension .abc) was designed to be a more robust, standard way of sharing information that was to avoid some of the version problems sometimes found with fbx format. This new format is easy to use in Houdini. Unfortunately you will not be able to export in the apprentice (H13) version but you can import alembic files. The educational license supports both import and export.
Import an Alembic
1. Bring in your alembic using File->Import->Alembic Scene
This will create an alembicarchive1 node in your network view (note, it may be out of view so look for it)
2. Set the path relative to $HIP and push Build or Update Hierachy and then Push Parameters to Children
3. If you will be importing the same file (ie. just animation changes) you may want to use an object merge node
For Houdini to Houdini
1. Use an ROP Alembic Output node with Format set to HDFS
2. When reading the file back in use Import as above - reference the bottom most node in your network
For Maya to Houdini
1. In Maya be sure that in Window->Preferences->Plug-in Manager that AbcExport.mll and AbcImport.mll are checked
2. On the top menu bar you will see Pipeline Cache then Export selection
Under Advanced Options check off Renderable Only and Strip Namespaces
3. Import as above
Example files to follow
Tip: Be sure to output your cameras separate from your models
Tip: Reference your camera in your mantra node
Tip: If your camera is giving you errors on the farm, delete the aperature key
Tip: Remember to set you camera resolution in your alembic, or override it in your mantra node