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Volume Slices and the IDL Slicer

Another useful volume visualization tool is IDL's SLICER3 procedure. The Slicer is a widget-based application that allows you to create iso-surfaces and pass cutting planes through 3-D datasets.

The IDL Slicer provides many other volume visualization techniques. As the name implies, the slicer allows you to look at slices through a volume dataset.

  1. To use the slicer with dataset B, it is first required to pass in a pointer to the data set by entering the following at the IDL Command Line:
    2. BDATA=PTR_NEW(HEAD_BINARY.B)

     

  2. Then enter:
    3. SLICER3,BDATA

     

  3. The IDL Slicer appears. The Slicer window will come up empty by default though the data is loaded. Be sure that the Mode pull-down menu is set to Slice which is the default. Position the pointer within the cube. Hold down the left mouse button and move the mouse. (In IDL for Macintosh, the mouse button is interpreted as the left mouse button.) An outline of the cutting plane appears. This plane moves only in the direction indicated by the orientation display. Move the cutting plane to the center of the volume and release the mouse button. A cross-section of the volume is displayed.

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    Figure 8-4: IDL Slicer3

    Figure 8-4: IDL Slicer3

     

  4. To make slices in different orientations, move the cursor into the large drawing window and press the right mouse button.

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  5. To simulate a right mouse button press, IDL for Macintosh users can hold down the command key and click the mouse. The orientation display changes to show the new direction of the cutting plane.

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  6. Click the right button a second time to see the third possible orientation.

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  7. Make slices in these orientations by clicking on the mouse button and dragging the cutting plane outline to the desired location.

  IDL Online Help (March 06, 2007)