It is sometimes desired to mask or hide certain elements, frequently so that other elements such as text are more readable. This can be done in Promis.e Standalone and Bentley Substation by using a filled shape that is the color of the background. The "BG" color is a special setting that will always match the color of the background while designing, and will not appear on printouts even if the designing background is black.
The example used by this article to demonstrate this technique will be a schematic cable symbol. This symbol is to be used on vertical wire segments, with the tag mnemonic appearing to break, or blank out, the wire without actually breaking or and inserting unwanted connections in the connection list. The technique can be used for other situations as well.
It is also possible to define a Text Style that specifies the Background color for masking purposes. This might work for this example, but it adds complexity.
The example in this article works in 2D design files only. For 3D design files, element elevations must be adjusted so the elements are truly in front of or behind each other.
This document assumes the user is familiar with symbol creation in general.
Select Create Symbol to create a new Cable type symbol and insert the tag mnemonic, the connection point, connection point text, and insertion point. Note that for cable symbols, there is a single connection point that should not fall on the wire so that the wire does not break. So the connection point is typically not in the same position as the insertion point. In this example the tag mnemonic ("CAB") has "Right Center" alignment and the connection point text ("?") has "Left Center" alignment so they can be placed near each other but never interfere.
Select the Place Block tool available via Manage > Component Management > Place SmartLine > Polygons > Place Block and other menus.
On the Place Block box that appears, set Area to "Solid", set Fill Type to "Opaque", and set Fill Color to "BG" (for background) by selecting the square in the lower right of the color grid, marked with "B".
Draw the block where the schematic wire should be masked when the symbol is placed. The block has masked the insertion point and connection point but not the text in the screen shot below.
Close the Place Block dialog or select the Element Selection tool.
Go to the last step on the Create Symbol wizard and save the symbol.
Be sure to create or modify at least one cable family and specify the new cable symbol in the family's roles since a family must be specified when placing a schematic cable symbol.
Priority is an attribute that elements in a 2D design file have. Elements with higher Priority appear "in front of" elements with lower Priority. Since the Priority of the device ID and other symbol text always gets set to 0 when the symbol is saved, it is not possible using Create Symbol to set the text to a higher Priority than the masking shape and still have the priority of the masking shape higher than the default of 0 for everything else such as wires. This must be done outside of Create Symbol.
Note: This process will have to be repeated if the symbol is subsequently modified using Create Symbol.
Alternatively, leaving the Priority of the text and masking shape at 0 will work fine when the cable symbol is placed on a wire. If, however, a wire is drawn across an inserted cable symbol, the wire will not be masked. To avoid this, always place the cable symbol after the wire is drawn or draw the wire with the Active Element Priority set to a negative value.
Note for 3D design files: Elements in a 3D design file can be assigned different elevations, or Z origins, so that they are truly in front of or behind other elements. Even though schematics are 2D by nature, schematic pages and symbols can still be 3D design files.
Keywords: wipeout box, wipe out, mask, hide, hidden