Creating and Editing Cells

This section covers how to create and edit cells.

Instead of creating cells “from scratch,” consider using the cell libraries supplied in MicroStation's sample workspaces. This could save you substantial time and effort. Also, many cell libraries can be purchased from third-party vendors. These cell libraries can be customized to meet your exact needs.

If you need a cell but cannot add one to a cell library (because, for example, a system administrator is in charge of the cell libraries in your company), consider using a group to place the same elements repeatedly in a design. A group is an unnamed cell that is not defined in a cell library. For more information about groups, see Using groups.

DWG workmode supports only shared cells. For more information, see Cells.

Cell type

When you create a cell, you define the cell origin (the location around which the cell is placed) and the cell type. There are three types of cells: graphic, point, and menu.

The symbology (color, line style, and line weight) of a graphic cell is determined when it is created, whereas a point cell assumes the active symbology when placed. A graphic cell rotates when a view is rotated, while a point cell is view-independent. A point cell can be especially useful for text.

A point cell has one “snappable” point — its origin — and is always placed on the Active Level, regardless of the level(s) on which its components were created. A graphic cell, however, is level-independent. That is, it can be placed on levels relative to the Active Level or on the same levels as when created, depending on whether Relative is on. The differences between graphic and point cells are summarized in this table:

	Graphic Cell	Point Cell
Level	level independent	placed on active level
Rotation	with view	view independent
Snap	to keypoints	to cell origin
Symbology	active settings when created	active settings when placed

The term “point cell” as discussed here refers to the Cell Type, which is assigned when the cell is created. This should not be confused with the “Active Point Cell,” which refers to a cell in a cell library that is designated for placement using the tools in the Points tool box . It is possible for a cell of either type — graphic or point — to be the Active Point Cell.

For information about menu cells, see Digitizing Tablet Menus.

To create a cell

1. If no cell library is attached, attach one before continuing. See To attach a previously existing cell library.


2. Draw the contents of the cell on the desired levels.


3. With the Element Selection tool, select all the elements to be included in the cell.
   or
   Place a fence that contains all elements to be included in the cell. See Specifying which elements are in the fence contents.


4. In the Cells tool box, select the Define Cell Origin tool.
   The prompt in the status bar is “Define origin.” The cell origin is the point that is used to position the cell in a design. When a cell is placed in a design, the cell origin will lie on the data point entered to position it.


5. Enter a data point to define the cell origin.
   The origin stays active and displays until the next time the Define Cell Origin tool is selected.


6. From the Element menu, choose Cells.
   The Cell Library dialog box opens.


7. In the lower right corner of the dialog box, click the Create button.
   The Create Cell dialog box opens.

   Create Cell dialog box



8. In the Name field, key in a name.


9. (Optional) In the Description field, key in a description.


10. From the option menu, choose the Cell type.


11. Click the Create button.

Alternatively, you can define the cell origin (steps 4–5) before selecting or fencing the elements (step 3) to be included in the cell.

One or more cells can be made part of another cell, or nested. Just select the cells to be nested when you create the new cell. If a cell with the same name as the nested cell exists in the library, the nested cell is replaced by a reference to the cell in the cell library. When the cell is placed, the reference is expanded back to the original geometry.

To edit the name or description of a cell

1. From the Element menu, choose Cells.
   The Cell Library dialog box opens.


2. In the list box, select the name of the desired cell.


3. In the lower right corner of the Cell Library dialog box, click the Edit button.
   The Edit Cell Information dialog box opens.


4. Edit the name, description, or both.


5. Click the Modify button.

To delete a cell from the attached cell library

1. From the Element menu, choose Cells.
   The Cell Library dialog box opens.


2. In the list box, select the name of the desired cell.


3. In the lower right corner of the Cell Library dialog box, click the Delete button.
   Since the deletion cannot be undone, an alert box opens, asking you to confirm that you want to delete the selected cell.
   see footnote 40


4. Click OK.

ByCell

When a cell is created, the symbology (i.e., color, line style and line weight) of each element is established. When that cell is placed in a DWG file, this symbology is used. However, it is possible to leave the symbology open-ended by using ByCell. If ByCell is selected as the color, line style and\or line weight, when the cell is placed the active attributes are used. For example, if a cell is created containing a square with color set to red and a circle with color set to ByLevel, when the cell is placed into a DWG file with color set to yellow, the square appears in red and the circle appears in the active color of yellow.

ByCell is enabled, by default, only in DWG workmode. You can enable ByCell in DGN workmode by adding _USTN_CAPABILITY > –CAPABILITY_NO_BYCELL to the workmode.cfg configuration file.