ACA: Custom Block for Railing Model Display Representation

The Model Display Representation of Railings in AutoCAD^® Architecture allow for the addition of custom blocks to create additional display components for the Railing. For example, you can add base plates to the Railing Posts. For this example, I started with the out-of-the-box Guardrail - Pipe Railing Style and renamed it to Guardrail - Pipe with Base Plate.

The first step is to create an AutoCAD Block Definition to represent the base plate. I decided that the base plate should be 5.5" long, 2" wide and 1/4" high, and I wanted to be able to use the same Material Definition that is used for the Railing, so I chose to use a Mass Element for the base plate, and created a Mass Element Style, called Stainless Steel, that had the same Material Definition assigned. In the example file, which can be found in this AutoCAD Architecture forum post, I used the out-of-the-box Metals.Metal Handrails and Railings.Stainless Steel.Satin Material Definition. Using the Stainless Steel Mass Element Style, I created a "Box" shaped Mass Element of the desired dimensions.

I then made a Block Definition with the Mass Element as the only included object, with the insertion point at the centroid of the bottom face of the Mass Element.

With the Block Definition created, the next step is to add it to the Railing. This is done in the Railing's Display Properties, in the Model Display Representation. Because I want this block to be added to all instances of this Railing Style, but do not want it to be added to all Railings, this was done as a Style-level Display Override.

• Edit the Railing Style.
• On the Display Properties tab, select the Model Display Representation. Depending upon what view direction and Display Configuration are current, this may or may not be the Display Representation in bold type.
  
• Left click on the toggle in the Style Override column on the Model Display Representation line to create a style-level override and open the Display Properties dialog for the overridden Model Display Representation.
  
• In the Display Properties dialog, select the Other tab.
• Select the Add button. This will open the Custom Block dialog.
• In the Custom Block dialog, select the Select Block button, and then choose the Block Definition that contains the base plate in the Select a Block dialog.
  
• Select OK to ratify the choice of block and return to the Custom Block dialog.
• Since we want this added to the Posts, in the Component area at the upper right, clear the check mark from the Baluster toggle and add one to both the Fixed Post and Dynamic Post toggles. We only want to add this block to the existing posts, not replace the posts, so leave the Replace toggle unchecked.
  
• Verify that none of the toggles in the Scale To Fit, Mirror In or Rotate areas are checked.
• Verify that the Insertion Point is set to Center for X and Y and Bottom for Z. This matches the insertion point of the RailingPostBasePlate block that was created.
• Verify that the Insertion Offset values are all set to 0.
• Choose an appropriate radio button in the Attach To area. Since I wanted all posts to have the base plate, I chose All in this example.
• Select OK to ratify the Custom Block settings, dismiss the Custom Block dialog and return to the Display Settings dialog.
• Select the Layer/Color/Linetype tab.
  
• Notice that there is a new Display Component listed, with the same name as the name of the Block Definition selected for the Custom Block. You can make any desired settings here, but since a Mass Element is the only element in the Custom Block, it will follow its own display settings for the Model Display Representation. The out-of-the-box drawing default settings display Mass Elements "By Material" for the Model Display Representation, just like all of the other Railing components. Since the same Material Defintion is assigned to the Railing components and the Mass Element in the Custom Block, they should all display alike. (If you really wanted to control the display properties of the Custom Block on the Layer/Color/Linetype tab of the Railing Display Properties, you could set a Style-level display override on the Mass Element Style for the Model Display Representation, clear the ByMaterial toggle and set all of the properties in the Mass Element Style Override to ByBlock. But that is not the goal in this example, and beyond the scope of this article.)
• Select the OK button twice, to accept all the edits made, dismiss the Display Properties and Railing Styles dialogs (or, if you edited the Railing Style with the Style Manager, to dismiss the Display Properties dialog and the Style Manager) and return to the drawing.

If you do not already have an instance of the Railing Style in your drawing, add one, and then change to one of the isometric view directions, if you are not in one already. You should see the Custom Block at the bottom of each post.

The baseplate will show whenever the Model Display Representation for Railings is active, which is just about any Display Configuration/View Direction combination where Railings are turned on, except for the Top view direction, where one of the "plan" Display Representations will be used. The Plan Display Representations do not allow for attaching Custom Blocks, but they do allow for adding Custom Profile Displays. An article on how to do that can be found here.