Selecting Using the Preselection Navigator

 

This task explains how to use the preselection navigator (or the keyboard arrows) for selecting hidden or coincident elements, or elements located elsewhere in the specification tree. Note that the preselection navigator cannot be used with selection filters.
Open the document Select.CATProduct.

Displaying the Preselection Navigator

Method 1

  1. Make sure the focus is given to the target graphic window. To do so:

    • Click anywhere in the graphic window.

    • Or, position your pointer anywhere in the graphic window and press Ctrl + F11.
    This step is not needed if the the Preselection navigator always started by keyboard arrows check box in the Navigation tab.

  2. Position your pointer over the object you want to select.

  3. Press any keyboard arrow (up, down, right or left).

    The preselection navigator appears.
 

Method 2

  1. Position your pointer over the object you want to select.

  2. Press Alt + the left mouse button.

Method 3

  1. Select Tools > Options > General > Display then the Navigation tab.

  2. Select the Display the preselection navigator after ... seconds check box, set the spinner to the time delay.

    The spinner sets the amount of time, in seconds, which elapses before the preselection navigator appears after pointing at an object.

  3. Make sure that the following three check boxes are selected as well:

    • Display immersive list for preselection navigator

    • Prehighlight faces for preselection navigator

    • Display immersive viewer for preselection navigator.

  4. Click OK to close the Options dialog box.

  5. Point to the part of the object you want to select.

    The selection tool is displayed after the time delay you set in step 2:
 

About display options
  As explained above, a certain number of options are available for customizing the display of your preselection navigator. Below are examples of what you see in the geometry area when these options are activated or deactivated:
 
  • Prehighlight faces for preselection navigator
    You can activate/deactivate the highlight of preselected faces by selecting/clearing the Prehighlight faces for preselection navigator check box under the Navigation tab.
    By default, this option is deactivated and in that case, the preselected face looks like this:
 

 

When the Prehighlight faces for preselection navigator check box is selected, the preselected face looks like this:
 

 
  • Display immersive list for preselection navigator
    You can activate/deactivate the immersive list's display by selecting/clearing the Display immersive list for preselection navigator check box. The immersive list displays all the stacked elements you can preselect.
    By default, this check box is activated which means that the immersive list is displayed as shown below:

 
  • Display immersive viewer for preselection navigator
    You can activate/deactivate the immersive viewer's display by selecting/clearing the Display immersive viewer for preselection navigator check box. The immersive viewer provides a visual feedback on the preselected element and lets you validate your selection.
    By default, this check box is selected which means that the immersive viewer is displayed as shown below:

When the Display immersive viewer for preselection navigator check box is cleared, the result is as follows:
 

 
  • Display auxiliary viewer for preselection navigator
    You can activate/deactivate the auxiliary viewer's display by selecting/clearing the Display auxiliary viewer for preselection navigator check box. The auxiliary viewer lets you perform viewing operations with the mouse such as zoom, rotate or pan.
    By default, this check box is cleared. When the option is activated, you see something like this in the geometry area:

The use of this check box is detailed further in this scenario.
 
  • Color
    The default color used to highlight selected and preselected elements is "orange" but you can choose other colors using the Selected elements and Preselected elements lists available in the Visualization tab.
    For instance, if you select a "pink" color in the Selected elements list, the result looks something like this:
 

 

Using the Preselection Navigator
The following diagram describes graphic selection tool features: 
 
  The preselection navigator is made up of the following elements:
  • A circle providing a visual feedback for the pointed object. This circle with an opaque background shows the preselected element and displays the surrounding elements in transparency. The circle keeps the proportions of the current viewer.
  • Arrow controls to navigate:
    • "In-depth" using up/down arrows.
    • Up and down in the object hierarchy using left and right arrows.
  • A cross pinpoints the preselected location. Four arrows are used for navigating or scrolling through the object you point at. These arrows turn black when you reach an extremity.
  • A list of all the stacked elements you can preselect. This list indicates the selection path and the identity of each element. This information is identical to the one displayed in the status bar.
    You can choose to display or not the immersive list of elements you can preselect (shown in the example below). To do so, select or clear the Display immersive list for preselection navigator check box in the Navigation tab.
  • An auxiliary viewer displaying the preselected object. This viewer also lets you perform viewing operations with the mouse such as zoom, rotate or pan. By default, this viewer is not displayed and has to be activated via the Navigation tab as explained further in this task.

An invisible area around the selection tool determines the tool's sensitivity.

 

  1. When the preselection navigator is displayed, click the up arrow to navigate "in-depth", in other words, from the front to the back of the object, to highlight hidden, superposed or coincident elements.

    This method is particularly useful for large parts since it lets you select, for example, edges, faces, etc. which are not visible or accessible near the front of the part.
    The cursor shape changes according to the type of the preselected element as shown below:
    point... edge...
    or face:  
     
    The identity of the preselected element is displayed in the status bar:
    Note:
    • The preselection navigator lets you use the contextual menu.
    • You can also navigate between different objects, not just inside single objects. When one object hides another, the preselection navigator also lets you select elements belonging to the hidden object.
    • When navigating with the keyboard arrows or when pointing at a too long element name in the immersive list, a tooltip is displayed to show the full name of the preselected element (which is truncated in the immersive list). If the name is short enough to be fully displayed, no tooltip appears.

  2. Click the down arrow to navigate in the opposite direction, towards the front of the object.

    There are two other ways to navigate using the mouse:
    • position your cursor over the circle, then click with the middle mouse button to navigate inside the object. As you click, the corresponding element path is highlighted in the list displayed to the right.
    • move the mouse over the list of element paths. As you do this, the element corresponding to each path you point at is pre-highlighted in the circle. Then, click the desired path to select the corresponding element.

    Moreover, when pointing at an element in the circle or at a path in the list, you can right-click to display the contextual menu as shown in the following two examples:
    Example 1 - when pointing at an element in the circle
    Example 2 - when pointing at a path in the list
    To select a contextual command, right-click it.

    You can also press the up and down arrows to achieve the same effect, and validate your selection by pressing Enter. Using any of these keys displays the selection tool automatically.
    The navigation is cyclic: when you reach the end of the selection path using the up and down keys, the preselection navigator automatically goes back to the starting point (i.e. the highest element in the hierarchy) and you can then re-start navigating.

  3. Click the left and right arrows to navigate up and down in the object's hierarchy. 

    For example, click the left arrow and look at the specification tree to see that each click on the left arrow takes you to the top of the tree, then click the right arrow to navigate downwards.
    Similarly, you can also press the left and right keys to achieve the same effect, and validate your selection by pressing Enter or using the left mouse button.
    When preselecting an edge, a prehighlight is also provided which is especially useful in case of overlapped elements:

  4. Select Tools > Options > General > Display then access the Navigation tab and select the Display auxiliary viewer for preselection navigator check box.

  5. Click anywhere in the geometry area, then position your pointer over the object and restart navigating by clicking the up or left arrow.
    An additional window opens and displays the object with the element you have preselected:

    The Auxiliary Viewer window lets you manipulate the object and perform viewing operations with the mouse such as rotate, zoom or pan as shown below:
    Rotate Zoom
    To hide the viewer, simply re-access the Navigation tab then clear the Display auxiliary viewer check box.

     

  6. To validate your selection and exit the preselection navigator, use one of the following methods below, depending on the display options that have been activated:

    • Click the circle in the center of the immersive viewer

    • Or, click the desired item in the immersive list

    • Or, click the element directly on the object.

    The item is selected:

The selection tool disappears, in any case, once a selection has been made, or if you point or click outside the selection activation area around the selection tool.