AbcView 1.1.0

AbcView is a graphical PyQt-based Alembic inspection and visualization tool. It offers a number of widgets to help you inspect and visualize your Alembic data, as well as assemble hierarchical scenes.

  • Object, property, sample and value widgets
  • Deferred loading for all Alembic objects
  • Hierarchical scene assembly (standard JSON format)
  • Python console for closer inspection of Alembic objects
  • Playback or step through animation using the Timeline widget
  • Per-camera render modes (box, fill, line, point)
  • Widgets are embeddable in other PyQt applications


AbcView has the following requirements:

  • Alembic 1.5+
  • Python 2.6+
  • PyAlembic
  • PyAbcOpenGL
  • PyOpenGL
  • PyQt4
  • argparse

For your convenience, AbcView comes with a csh wrapper that sets up your environment for running AbcView from your Alembic build directory. To build the wrapper inside your Alembic build dir, make sure the “examples” subdirectory is active in the /python/CMakeLists.txt file


Basic Usage

Loading one or more Alembic scenes or AbcView sessions

abcview [file1 .. fileN] [OPTIONS]

positional arguments:
  filepath              File to open.

optional arguments:
  -h, --help            show this help message and exit
  -f FRAME, --frame FRAME
                        Frame to load in viewer.
  --first FIRST         Set viewer first frame value.
  --last LAST           Set viewer last frame value.
  --bounds              Force scene bounds display mode.
  --review              Use review display settings.
  --reset               Reset settings.
  -v, --verbose         Verbose output.
  --script SCRIPT       Load and execute Python script.

Using the --bounds option tells AbcView to force displaying scenes in bounding box mode. If the .childBnds property is written at export time, this means that AbcView can get the bounds information from the archive rather than the GL scene, which usually means a much faster load time.

Save your session at any time using File->Save/Save As. Loading a saved session is the same as loading an Alembic scene

$ abcview

Display Modes

AbcView supports various OpenGL display modes for scene data. Each scene and camera can have their own display mode.

Scene display modes are available by right-clicking on a scene in the Objects widget:

  • Clear - Inherit the display mode from the camera
  • Off - Do not display this scene
  • Fill - Display in selected scene in smooth shaded mode (default)
  • Line - Display the selected scene in line mode
  • Point - Display the scene in point mode
  • Bounds - Per-object bounding boxes [1]

Camera display modes are available by right-clicking anywhere in the Viewer widget:


AbcView also has a concept of “load state”: each scene has a load state value of either true or false. This value is changed by clicking on the “eye” icon in the Objects widget next to the scene. Toggling the load state will tell AbcView to load or unload the scene from the GL Viewer, but it is still available in the Objects widget.

A scene’s load state is stored in the session .io file as “loaded” under the scene item.

"items": [
        "loaded": true,

[1] Note: Object bounds is different from scene bounds (Shift+B). Turning on the scene bounds option will display a single bounding box for the entire scene, and object bounds is a scene display mode that shows bounding boxes for each object within that scene.

Console Widget

The Console widget is an embedded Python interpreter (the same Python process currently running AbcView) with preloaded Python modules and convenience handles.

Pre-loaded modules:

Convenience handles to AbcView widgets:

  • app - Main application accessor
  • objects - Objects widget accessor
  • properties - Properties widget accessor
  • samples - Samples widget accessor

Accessing the current Session in the console, or in a script that gets called from an AbcView session, is therefore simply:

>>> app.session

Importing a session or Alembic cache:

>>> app.import_file(filepath)

Getting a handle on the currently selected object, property or sample:

>>> objects.selected()
<alembic.Abc.IObject object at 0x211ccc8>
>>> properties.selected()
<alembic.Abc.IArrayProperty object at 0x21816b0>
>>> samples.selected()
<imath.V3fArray object at 0x1ff81a0>

The current state of the viewer can be accessed like this:

>>> app.viewer.state

The list of loaded scenes and cameras can be access from the state object:

>>> app.viewer.state.scenes
[<GLScene "">]
>>> app.viewer.state.cameras
[<GLCamera "interactive">, <GLCamera "side">]

Note: AbcView can have multiple viewer and camera instances (RMB->Layout->Split). The app.viewer accessor is always set to the current viewer, that is, the one most recently interacted with. Clicking on another viewer window will change the value of app.viewer.


The above screen capture shows the value of app.viewer changing after clicking on each viewer widget.

Python API

You can inspect and manipulate session data using the AbcView Python API, for example

>>> from import Session
>>> s = Session()
>>> s.add_file("")

There are a number of properties you can set on session items, such as TRS values, color and GL rendering mode

>>> from import Mode
>>> item = s.items[0]
>>> item.mode = Mode.FILL

Change the display color

>>> item.color = (0, 255, 0)

Set transation, rotation and scale values

>>> item.translate = (10, 0, 100)
>>> item.rotate = (0, 90, 0, 0)
>>> item.scale = (1, 1, 1)

AbcView supports both custom non-animated Cameras and loading ICameras from Alembic archives. To load an ICamera from the GUI, navigate to the ICamera in the objects widget and right-click->view through selected. You can also add it to the session using the IO module

>>> from import ICamera, get_object
>>> s.add_camera(ICamera(get_object("",

For a more complicated example, check out the contextual overrides example.

Writing Scripts

Writing scripts for AbcView is straight-forward. Anything you can do in the Console widget can be saved to a script file and called from the AbcView Scripts menu.

Script Configuration

The Scripts menu is populated by looking for .py files along the paths defined by the ABCVIEW_SCRIPT_PATH environment variable, or by placing files in the scripts subdir of the abcview Python package. Script directory definitions can also be configured in the lib/abcview/ file.

There are few restrictions on what you can write in an AbcView script. Scripts are executed by AbcView’s console widget, which simply makes a call to execfile in the current AbcView session.

Defining a Python docstring at the top of your script will populate the menu tooltip as you mouseover scripts in AbcView. For example

My Awesome AbcView Tool

The name of the script, version and author are similary defined using private attributes, for example

__name__ = "My Awesome Tool"
__version__ = "1.0"
__author__ = "Joe Animator"