Putting Design on Display

This month, we'll focus primarily on controlling the graphical display and output of your design files. Because the consumer base of our designs and design alternatives is ever increasing, your design plays an important role as a primary communication and decision-making vehicle; therefore, the clarity of the presentation is crucial.

You'll learn to apply transparency to references and to clip or mask volumes in one operation. Additionally, you will learn to change the fundamental mode by which MicroStation commands operate.

Transparent References

A design project is an ever increasing collection of files, types, and disciplines. One of the challenges is to communicate your design alternatives in a rich graphical manner. When your design presentation encompasses several levels of information, you are sometimes required to either adjust your thinking to the capabilities of your software or export your design data for processing in a separate graphics package.

MicroStation's References can be an effective design and collaboration tool. One of the nice options is the ability to control the transparency of any Reference within the current design session. The Adjust References Color utility modifies or adjusts the intensity of element colors in an attached reference for display, as shown in Figure 1.

• From the File menu, select Reference.
• From the References dialog, select Settings > Adjust Colors.
• From the Adjust References Colors dialog, make the desired adjustments.

Figure 1. You can use the Adjust References Color utility to modify or adjust the intensity of element colors.

First, let's look at the options for adjusting reference color.

• Value sets a multiplier that is applied to every color in the color table in HSV (Hue, Saturation, Value) color space. When Value is set to 50, the value for every color in the color table is multiplied by 0.50. Moving the Value slider to the left lowers the brightness of the color table.
• Saturation also sets a multiplier that is applied to every color in the color table in HSV color space. When the Saturation slider is set to 50, saturation for every color in the color table is multiplied by 0.50. Moving the Saturation slider to the left lowers the contrast of the color table.

When the proper settings have been chosen, select OK to apply the color adjustments, redraw the selected references, and close the dialog box. If you prefer to key-in a command, use the following:

reference adjustcolors
< value, saturation,
reference_specification > >

The syntax allows wildcards, matching both the reference filename and logical name, as is the case for all reference commands.

Escape from a Command

By default, MicroStation command modes operate in a manner consistent with most Windows-based design applications. The current selected command remains active until you select another function. However, some would like the ability to stop the current operation by simply pressing the ESC key on the keyboard. In order to allow the ESC key to stop the current operation, we simply need to change our Input Preferences with the Workspace Preferences control panel.

Workspace Input Preferences consist of controls that are used to set preferences for keyed input and pointer drag operations, as shown in Figure 2. To make the change, follow these easy steps:

• From the Workspace menu, select Preferences.
• From the Preferences dialog, select the "Input" category.
• Select the Allow ESC key to stop current command toggle.
• Select OK to activate.

Figure 2. Workspace Input Preferences consist of controls to set preferences for keyed input and pointer drag operators.

Once the feature is turned on, pressing ESC deactivates the selected tool and activates the Default Tool chosen in the Look and Feel category.

Clip and Mask References

Let's explore the ability to limit the displayed volume for a particular view. To accomplish the task of both clipping and masking a portion of your design, you'll use MicroStation's View Control. The View Control toolbox contains several tools for manipulating views in the active DGN file.

For this exercise we will specifically introduce a clipped volume. When a clip volume is applied to a view, only the elements located within the clip volume will display, or can be snapped to, in that view. Traditionally, clipping elements consist of any solid or closed extrusion, cylinders, or closed planar elements. When a planar element is chosen, the clipping volume is generated by sweeping the planar element through the entire design. Planar elements may be selected in any view. Any modification to the planar clipping element will result in updating the clip volume. To remove the clipped volume, simply delete the element used to apply a clip volume.

As shown in Figure 3, in order to perform a clip and mask a view in one operation, we will incorporate Group Holes, as a subtracted region, into the planar boundary element resulting in a composite planar region. The Group Holes key-in is used to identify a solid element and the hole elements to be associated with the solid. The solid and its associated holes can be shapes, ellipses, and/or complex shapes that are in the same plane. Holes are not patterned and appear "transparent" in rendered views. You can group a solid and holes as follows:

• Key-in Group > Holes.
• Identify the solid element.
• Identify the hole elements to associate with the solid.

Figure 3. With MicroStation's View Control, you can limit the displayed volume for a particular view, by clipping (3A) and masking (3B) portions of your design in a single operation.

The solid and holes are consolidated into a group (orphan cell). The area attribute (solid or hole) of each element is set appropriately. The holes immediately follow the solid in the group definition.

Now that we have our composite planar clipping region identified, we simply apply this region to our active view to clip and mask in one operation as follows:

• Place an element to be used as the clipping element.
• From the Tools menu, select the View Control option.
• From the View Control Toolbar, select the Apply Clip Volume control.
• In the tool settings, set Method to Single View.
• Identify the clipping element.
• Accept the clipping element in the view you want clipping applied to.

Finally, the planar region remains interactive. Should you change the shape of the composite image, boundary or holes, the clipping volume and masked areas will dynamically update. I welcome your MicroStation tips. You can email them to me at james.dyer@bentley.com.

Until next time, enjoy MicroStation!