Clip Mask

Used to mask the display of elements in a view that are located within the region of a clipping element. When a clip mask is applied to a view, only elements that are located outside the range of the clipping element will display, or can be snapped to, in that view. Each view may have a different clip mask applied.

Operations, such as view rotation, fence processing, hidden line removal, and rendering, honor the clip masks. They ignore any elements that are not displayed in the view.

Clipping elements may consist of any solid (other than feature solids) or closed extrusion, cylinders, or closed planar elements (shapes, circles, ellipses, complex shapes, grouped holes). Additionally, cells can be selected as a clip element, in which case each component of the cell that is valid for masking will generate a separate mask volume.

Where a planar element is chosen, the clipping volume is generated by sweeping the planar element through the entire model. Planar elements may be selected in any view, because the sweep direction is orthogonal to the plane of the element.

If you later move, or modify a clipping element, then the clip mask is moved or modified also. If you delete a clipping element, then the clipping is removed also. Clipping elements can be manipulated/modified with the standard MicroStation tools.

Once a clip mask has been applied to a view, you can switch the clipping on and off via the Clip Volume check box in the View Attributes dialog box (Settings > View Attributes). Similarly, you can toggle the display of the clip element via the Show or Hide Clip Mask Element icon in the tool settings.

May be used in conjunction with clip volumes. In these situations, the only elements that will display are those that are located within the clip volume and outside the clip mask.

Tool Setting	Effect
Display Clip Element	If on, the clip element remains displayed after creating the clip mask for the view. Display of this element can be toggled on/off later, with the Show or Hide Clip Mask Element icon.
Close Element button	(Apply Clip By Polygon only) Closes the polygon clipping element.
Apply Clip Mask By Element icon	Applies a clip volume from an existing element.
Apply Clip Volume By 2 Points icon	Lets you apply a clip mask by interactively defining a rectangular clipping element with two data points. The clipping mask is created by sweeping the defined clipping element through the entire model.
Apply Clip Mask By Polygon icon	Lets you apply a clip mask by interactively defining vertexes of a polygon with data points. The polygon can be closed by entering a data point at the start point, or by clicking the Close Element button. The clipping mask is created by sweeping the defined clipping element through the entire model.
Apply Clip Mask By Element Range	Applies a clip mask that encloses the range of a selected element or group of elements. If a selection set is active, the clip element will enclose the entire group of elements.
Show or Hide Clip Volume Element	Toggles the display of a view's clip mask element. Typically, the clip element would not be displayed in a view, but needs to be if you want to modify or move the element, or merely to check its location.
Clear Clip Mask	Removes the current clip mask from a view. If the clip element was generated by the Apply Clip Mask tools, then the clip element is deleted. If the clip element was created from an existing element, then it is disassociated from the view, but not deleted.

To apply a clip mask by element

1. Place an element to be used as the clipping element.


2. Select the Clip Volume view control.


3. In the tool settings, click the Apply Clip Mask By Element icon.


4. Identify the clipping element.


5. Accept the clipping element in the view to which you want masking applied.

To apply a clip mask by 2 points

1. Select the Clip Mask view control.


2. In the tool settings, click the Apply Clip Mask By 2 Points icon.


3. Enter 2 data points to define diagonally opposite corners of a rectangular clip element.
   If only one view is open, then the clip mask is applied.


4. If more than one view is open, enter a data point in the view to which clipping is required.

To apply a clip mask by polygon

1. Select the Clip Mask view control.


2. In the tool settings, click the Apply Clip Mask By Polygon icon.


3. Enter data points to define vertices of the polygon.


4. When all vertices are defined, click the Close Element button to close the polygon.
   If only one view is open, then the clip volume is applied.


5. If more than one view is open, enter a data point in the view to which clipping is required.

To apply a clip mask by element range

1. Select the Clip Volume view control.


2. In the tool settings, click the Apply Clip Mask By Element Range icon.


3. Identify the element to be used for the clip mask.


4. Accept in the view to which you want clipping applied.

To apply a clip mask by element range for a group of elements

1. Use the Element Selection tool to select the elements about which clipping is required.


2. Select the Clip Volume view control.


3. In the tool settings, click the Apply Clip Volume By Element Range icon.


4. Accept in the view to which you want clipping applied.
   Separate clip masks are set for the range of each element in the selection group.

To apply a clip mask by element range for a cell

1. Select the Clip Mask view control.


2. In the tool settings, click the Apply Clip Mask By Element Range icon.


3. Identify the cell.


4. Accept the cell in the view to which you want clipping applied.
   A single clipping mask is set to enclose the elements in the cell.

To toggle the display of the clipping element

1. Select the Clip Mask view control.


2. In the tool settings, click the Show or Hide Clip Mask Element icon.


3. Enter a data point in the view in which the clip mask was created.

To clear a clip mask

1. Select the Clip Mask view control.


2. In the tool settings, click the Clear Clip Mask icon.


3. Enter a data point in the view in which the clip mask was created.

Key-in: view mask icon