orbyThe topics in this section include:

Each OpenSim 3D View window is a VTK window. VTK is an open source visualization package distributed by Kitware Inc. (www.kitware.com). VTK windows come with a built-in set of key bindings that you can use to navigate within the window and to perform rotations, pan, and zoom operations. The key bindings differ, depending on whether you are running OpenSim on a Windows, Mac, or Linux platform.
On Windows, you can translate and rotate in the 3D View window using the following:


Rotate by clicking the left mouse and dragging.


Pan by clicking the center mouse and dragging left or right, or by clicking the left mouse with shift and dragging left or right.


Zoom by clicking the right mouse and dragging up or down.


Refit the models in the view window by typing "r".


Center an object in the window by selecting the object (ctrl+left mouse) and typing "r".

The 3D View window comes equipped with a set of standard buttons to make it convenient to orient the objects in the 3D View according to your preferences. These buttons appear in a Toolbar, which is located by default along the right edge of the 3D View window but can be dragged to any of the four sides of the 3D View window. The following buttons are available in the Toolbar:

Change background color. A color chooser is brought up when this button is clicked and the background of the current 3D View is set to the new color you select. This new color is saved in User Preferences so that future 3D View windows come up with this new background color.

Look at the model from the world's –X direction. Note that multiple models could be loaded and each model could have its own concept of "front," but there's one unambiguous –X direction within the world's coordinate system. Similarly, = +X, = -Y, = +Y, = -Z, = +Z.

Toggle the display of world coordinate axes on and off.

Take a snapshot of the view. When you click this button, a file browser is brought up and you are prompted for the name of a .tiff file in which to save the 3D View.

Record a movie. Clicking this icon toggles movie recording on and off.

Create or edit a Camera Dolly for custom camera positioning. Details are covered in Snapshots and Movies.

Annotate objects in the 3-D view.

The following set of hot keys are available and can be used to achieve some of the same functionality that is available through the ToolBar:




Zoom in


Zoom out


View along the X axis (of the world coordinate system)


View along the Y axis (of the world coordinate system)


View along the Z axis (of the world coordinate system)


Refit selected objects in the view window. All models are fit inside the view window if nothing is selected.

jRotate left around vertical axis.
kRotate right around vertical axis.

Selecting objects in the 3D View is a fundamental part of the graphical editing capabilities available in OpenSim. It makes it easier to perform tasks, such as moving muscle attachment points. The following operations are supported:


Select an object using double click (3.2 and later) or ctrl+left mouse (all versions). An object that has been selected will be colored yellow, and its name will appear in the status bar. Selection is possible only on the current model. Objects can also be selected by double clicking on them.


Add another object to the current selection group using shift+ctrl+left mouse. Re-selecting an object toggles its selection.


Clear all selections by using ctrl+left mouse in an empty area of the view.


Drag objects by selecting them and then use the left mouse to click and drag the object to its new location. Currently only dragging of muscle points is supported.

OpenSim allows you to annotate objects in the 3D View. This is accomplished by selecting the button . . This is a toggle button that reverses colors when activated. While activated, picking any object in the 3D View (e.g., bodies, markers or muscle points) will cause the object's name to be displayed in the 3D View in white text. Multiple objects can be selected using the SHIFT key. Deselecting the button will remove all annotations from the 3D View.