Modules:Fiducials-Documentation

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Fiducials Module GUI

The Fiducials Module creates and manages lists of Fiducial points.

Making New Fiducials

New fiducials can be created in multiple ways:

Click on the tool bar icon of an arrow pointing to a starburst fiducial to enter the 'place a new object mode', then use the mouse to left click on 3D models or on 2D slices to show where you wish to place your fiducials.

You can also place fiducials while in 'tranform view' mode by positioning the mouse over a 2D slice plane in the Slice view windows (it must be the active window) and pressing the 'P' key.

Interaction

You can then click and drag the fiducial using the mouse in 'transform view' mode. 3D interactions are possible by clicking and dragging the fiducials in the 3D window.

You can reset the positions of the fiducials in the table that appears in the 'Add, Configure and Delete' section of the Fiducials GUI.

Double click on the fiducial name, or position, to edit it manually. Each fiducial can also be selected or unselected, and visible or invisible. The 'Adjust Display Properties' tab controls the visibility of the list as a whole.

The distance between the first two selected fiducials in the list will be computed automatically and appear in a label below the list of fiducials. This distance is in milimetres.

To align slices with fiducials, move the fiducial while holding down the Control key. You can use the '`' (backtick) key to jump to the next fiducial, Shift-` to jump backwards through the list.

Use the backspace or delete key to delete a fiducial over which you are hovering in 2D.

Argument Lists

Fiducials can be passed as a list of points to a command line module, for example to do ACPC registration. Only the points that are selected in the list are passed to the command line module, so you can adjust which points are used for calculating the output.

Display

The display properties of the fiducials in the list can be adjusted by expanding the 'Adjust Display Properties' tab:

There is a long list of glyph types available, each list can have a different glyph type, as well as colour and size properties. The default is the 2D starburst, but 3D glyphs are also available.

The following image shows what these types of glyphs look like in 3D:

The various lists have had their fiducial glyph sizes scaled, and the selected colours changed by selecting the appropriate list from Fiducial List drop down menu and then using the 'Adjust Display Properties' widgets. The text size can be scaled as well, as well as the visibility of all the fiducials in the list toggled on or off. The opacity of the fiducials can also be adjusted between 0 and 1.