November 27, 2016

ACA: Interference Condition vs Subtraction in Area Calculations

For all of the work I have done with the Schedule Feature of AutoCAD® Architecture over the years, I have not done much with trying to produce accurate Space Schedules, particularly where Interference Conditions and/or Linework Subtraction is involved.

A question came up the other day about this, and I was surprised to learn that even though an Interference Condition "removes" any visible Hatch Component from a Space in a plan (Top) view, it does not have any effect on any of the reported Area properties of a Space. I did discover that using the AecLineworkSubtract command, the area removed does affect the reported area. I cannot speak to the reasons behind this, but given that an Interference Condition (SpaceInterferenceAdd command) only affects the Floor/Floor thickness of a Space, whereas the AecLineworkSubtract command removes the projected 3D volume of a selected 2D Polygon from bottom to top of a Space, perhaps that would be considered to be "by design".

Some additional notes regarding the use of the AecLineworkSubtract command:
  • As noted in the previously linked article on the AecLineworkSubtract command, associative Spaces are not affected (even though the command will allow you to select them as objects from which to subtract). See below for a partial exception when Manual offset boundaries are used.
  • The setting of the Offset boundaries property of a Space (By style, By Standard or Manual) will affect how the AecLineworkSubtract command works.
  • When the Offset boundaries property is set to By style, if the Space is not associative, the AecLineworkSubtract command will affect all of the reported Area values (Gross, Usable, Base and Net), with the offsets specified in the Space Style (on the Design Rules tab, at the bottom right) applied to the area to be subtracted as well. Depending upon the size of the offset and the dimensions of the area to be subtracted, it is possible that some or all of the area to be subtracted could be negated by the boundary offset, giving the appearance of there being no effect. If the Space is associative, then the AecLineworkSubtract command will have no effect.
  • The By Standard offset boundary option is only offered for associative Spaces, so the AecLineworkSubtract command will have no effect on Spaces with this setting.
  • When using Manual offset boundaries with non-associative Spaces, only the the boundaries that are currently set to be editable will be affected by the AecLineworkSubtract command. You can toggle the editability of a boundary using the round gray grips that appear around the location grip or by selecting the Space, right clicking and choosing Edit Boundary and then the boundary whose status you want to toggle, from the context menu.
    The All option on the context menu, only offered when all are not already enabled, will enable all four boundaries. The Reset option on the context menu will enable just the Base boundary. For an associative Space with Manual offset boundaries, only the Gross, Usable and Net boundaries can be manually edited; the Base boundary is associative to the bounding elements. The AecLineworkSubtract command will have no effect on the area reported for the associative Base boundary, but will be applied to the three editable boundaries.
Note: AecLineworkSubtract and LineworkSubtract are two names for the same command. The autocomplete function only recognizes LineworkSubtract, so if you are going to type the command name, omit the "Aec".

November 12, 2016

ACA: WALL Command

I was asked a question about the various command line options for the WALL command in AutoCAD® Architecture, and was surprised to find that the online Help does not have an article on this command. I suppose that, in recent years, most people use the WALLADD command to add a new Wall, most likely through a Tool Palette tool, Ribbon tool or the Styles Browser, but the WALL command still exists. There are other ways to execute the other options as well. The heyday of the WALL command was most likely back in the early days, before Tool Palettes and the Styles Manager (let alone the Styles Browser), but if it is good enough to remain in the program, it should be covered in the Help.
For ease of future reference, here are my findings on the command line options:
  • Add: This option is the equivalent of running the WALLADD command, and allows you to create a new Wall.
  • COnvert: Use this option to select lines, arcs, circles, or polylines and convert them into Walls. You will be given the option to keep or delete the selected linework. Using this option appears to result in a Standard-style Wall, regardless of what the current drawing's default Wall Style is. You may be better served by right clicking on a Wall tool on a tool palette which references the desired final style and then choosing Apply Tool Properties to > Linework from the context menu. (Applying a style to linework is not available from the Styles Browser.)
  • Properties: Use this option to select one or more Walls and have the Properties palette open (if closed) and display the Wall's properties. Unless you do not keep the Properties palette open all the time, this option is fairly worthless. Even if you keep it closed, selecting the Wall, right clicking and choosing Properties from the context menu is faster than typing WALL and choosing the Properties command option. It is a relic from the bad old days before the modern Properties palette, when each AEC Object had its own Properties dialog.
  • Styles: Opens the Style Manager, filtered for Wall Styles.
  • CLeanup groups: Opens the Style Manager, filtered for Wall Cleanup Group Definitions.
  • Dimension: Allows you to select one or more Walls and have AutoCAD Dimensions (not AEC Dimensions) added to it/them. The dimensions will be oriented parallel to the first Wall selected, so choose wisely.
  • Interference: Allows you to add or remove a Wall interference. If you are going to add an interference, you will need to have the AEC object(s) that will be the interfering objects in the drawing and selectable prior to executing the command. Likewise, to remove an interference condition requires that the AEC Object(s) doing the interfering are selectable when the command is run, so if any are on layers that are Off or Frozen, you will want to turn those layers On and/or Thaw them and your display settings need to have an active Display Representation that has visible graphics for those objects.
  • Reverse: Reverses the direction of one or more selected Walls. More easily done for individual Walls with the flip grip in more recent versions of the program, but if you had a reason to reverse the direction of a large number of Walls at once, do not want to maintain the location of the justification line, dislike using tools on contextual ribbon tabs or right-click menus and would rather not click on all those flip grips, one by one, the Reverse option of the WALL command is the way to go.

November 05, 2016

Off Topic: SEPTA Strike, Work Week 1

The union representing the City Division of the local transit agency, SEPTA, went on strike at midnight, Monday, October 21/Tuesday, November 1, leaving me with a six-mile walk to get to work each morning and again on the return trip. I usually try to get 10,000 steps in every day (weather and schedule permitting), but the strike has me over that before I even get to the office each morning.
Both sides in the negotiations have been feeding at the public trough for so long that they have forgotten that most of the people who provide the money that pays for their salaries and benefits through fares paid and tax-payer funded subsidies make quite a bit less in total compensation for equivalent levels of education and experience, and that those very people are the ones hurt most by their grandstanding and inability to compromise. Drive enough people away from using public transit, and there will not be any money to argue over.

October 30, 2016

ACA 2015 & 2016: Missing Tools in Layer Properties Manager

If you are using AutoCAD® Architecture 2015 or 2016, you may find that the New Property Filter, New Group Filter, New Standards Filter and Layer States Manager tools in the Layer Properties Manager are missing from the tool bar at the top.
As noted in this Autodesk Knowledge Network article, if you collapse the Layer Filter Tree, the missing tools will appear.
You can then expand the Layer Filter Tree, and the tools will remain visible.

Here is a brief Screencast showing this in action.

10/31/2016 UPDATE: The same issue can arise in the 2017 release, and the same workaround will bring the missing tools back there, as well.

October 26, 2016

Autodesk Answer Days

Another Autodesk® Answer Day is scheduled for October 27, 2016 (tomorrow!). This event will be held in both English and, for the first time, German. Autodesk staff will be scouring the forums for the included software, focused on product design, and providing answers to questions posted.

The German event covers AutoCAD and Inventor and takes place between 10:00 am and 5:00 pm Central Europe Time.

The English event covers AutoCAD, Inventor and Fusion 360 and takes place between 6:00 am and 6:00 pm US Pacific Time.

Read more about the event here.

October 20, 2016

Revit Families: Yes/No Parameter Defaulting to No

When you add a Yes/No parameter in a Revit® family, the initial default value is "Yes" - the box in the Value column is checked. If you only have one Type in your family at the time, it is easy enough to uncheck the box if you want it to be set to "No" and to have the value be "No" for any other Types created while that Type is current.

But there are occasions, such as for visibility parameters, where a family may get created, with multiple Types, and then later edited to add a new Type that requires a new Yes/No parameter that should only be turned on for the new Type. It is tedious to set each existing Type current and uncheck the newly added Yes/No parameter if there are more than two or three existing Types. Unfortunately, there is no way to specify the initial value for a newly added Yes/No parameter. Thanks to this post in the Who's afraid of the Big Bad BIM? blog, I have worked out a way to quickly get all types set to "No". I believe that what follows is the full intent of what the original article posted, but the article stops short of clearing the formula so that one or more of the Types can be set to "Yes" and therefore also does not note the need to change to a different Type when clearing the formula, so that all Types remain unchecked. [Perhaps that was not necessary in whatever version Erik was using in the summer of 2012 when the article was written.]

  1. Add a new Yes/No parameter to a Revit family with multiple Types, in which you want most of the Types to be set to "No".
    Note that all of the Types will be initially set to "Yes" (checked).
  2. In the Formula column for the newly added Yes/No parameter, type 1=0, and then press the ENTER key. Any expression that evaluates to false will do.
    Note that the toggle in the Value column is now unchecked, but it is also grayed out and locked, because it is being controlled by the formula.
  3. Set a different Type to be the current Type.**
  4. Delete the formula for the newly added Yes/No parameter.
  5. All of the Types are now set to "No". If you want any to be set to "Yes", set each one current, in turn, and select the toggle to check it.
The Screencast below shows the above steps in action. It also shows a second Yes/No parameter being added where the formula is deleted immediately after it was added, with the result that only that one Type is set to "No".
** - In Revit 2016, I found that if I deleted the formula in the Type in which I originally placed it, immediately after placing it, that only that Type remained set to "No", and the others remained checked. If you want, you can change to another Type and then change back to the original to do the deletion. There may be other actions which will "set" the "No" values for all Types.

September 02, 2016


I have been working on files that were created by others recently, and they contain a large number of Block References created using the PASTEBLOCK command, and left with the random name that gets assigned to the Block Definition by the PASTEBLOCK command. The names all start with A$C, followed by eight characters that appear to be a hexadecimal number. I find this very annoying, as you have no idea what is in any of these blocks, whereas you might if a meaningful name had been given.

Part of my current task required me to find things inside these annoying Block References, so I have been WBLOCKing them out to separate files and then opening those files to view the contents in isolation from all of the other things in the original file. I made an interesting discovery: when opening these files, the file name does not appear in the title area of the AutoCAD window and, in AutoCAD Architecture 2014 and 2016 (and, I suspect, all other versions that have File tabs), a file tab is not generated for these files. They are listed by the Switch Windows tool on the View ribbon tab, on the Windows panel, and they also appear in the Application Menu's Recent Documents list. So why do they not have drawing tabs or have their names in the title bar?

I thought there might be something wrong with my installation, so I did some admittedly brief searching on the Internet and in the online Help, and did not find any mention of this "situation." Surely I cannot be the first person to try this; perhaps I am the only one who thought it was odd.

It does not appear to be anything inside the WBLOCKed file itself. If I save the file under a different name, that does not follow the format of A$C followed by a hexadecimal number, and open that file, the file name will appear in the title area and a drawing tab will be generated. If I manually create a file and save it with a name that does follow that format (the length of the hexadecimal number does not appear to matter; so long as all of the characters that follow the initial A$C are taken from the numerals 0-9 and the letters A-F), when opened, the file name will not appear in the title area and a drawing tab will not be created.

This is not that big of a deal; I am writing this so that when I come across this in five years, having forgotten about it in the mean time, there will be at least one Internet source that discusses it.

August 24, 2016

Dropbox and Open/Save Issues in AutoCAD and Revit

Like many others, I experienced the problem with the 8.4.19 (8/16/2016) build of Dropbox. In my case, Revit® 2014 would display the whirlpool of death when selecting Open > Project from the Application Menu or selecting the Open link under Projects in the Recent Files window. I did not have any problems with AutoCAD®.

I just forced the current build of Dropbox to install (8.4.21), and I no longer have that issue.

For the record, here are the Autodesk Knowledge Network articles related to this issue:
AutoCAD becomes unresponsive when opening or saving files
Revit: Hang when clicking Open after recent Dropbox update

August 14, 2016

Dynamo - Element Parameters

If you are relatively new to Dynamo and not intimately familiar with the Revit API, like me, you may find this relatively simple graph of use.
The Select Model Element node at the upper left allows you to select an element in your Revit model and will report back, through the two Watch nodes at the right, the available instance parameters and their current values. These are the parameters that work with the Element.GetParameterValueByName and Element.SetParameterValueByName nodes. This can be helpful in identifying the parameter you need to access for a particular task.

The Element.Parameters node generates a list of these parameters, the Element.Name node takes that list and turns it into a list of the parameter names, as strings, and the List.Sort node sorts that list alphbetically. The left Watch node displays this sorted list; the list is also fed into the Element.GetParameterValueByName node, which generates a list the values for those parameters, for the selected element, and displays them in the right Watch node. My experience has been that the Element.Parameters node will list the parameters found in what seems like a random order that makes it hard (for me, anyway) to track them from element to element. The description of the Object.Identity node states that it passes out what is passed into it, doing nothing, which, I suppose, it true, but I included it here because by locking the Data Preview of the node in the open position, it shows the element category as well as the element ID number, whereas the Select Model Element node only shows the element ID number. Seeing the element category helps me be sure that I selected the desired element correctly.

Here are two screen shots of this graph in action, one with a Wall selected, and the other with a Dimension selected.
As always, you can select any of the images to see it full size.

July 29, 2016

ACA/AMEP: "BIND" Bound External Reference Named Object Naming

Whenever possible, I try to avoid binding External References with the BIND option; I prefer to use the INSERT option when I cannot leave the references as external. In cases where the "root" layer (for example, A-Door) has the same layer attributes and is treated the exact same way, whether as a "live" layer in the host file or a layer within one or more external references, using the INSERT option simply combines all of the various layers with the same root name into one layer (A-Door in the example here). But there are times when one has to work on a project done by others (perhaps, many others, over a long period of time), where the various layers with the same root name (A-Door, External01|A-Door, External02|A-Door, etc.) are not treated the same way, in particular, with regard to on/off, freeze/thaw and/or viewport freeze/thaw status. If A-Door is on, thawed and viewport thawed, External01|A-Door is globally frozen and External02|A-Door is viewport frozen, using the INSERT option of the BIND command will not preserve what is seen in the sheet. (Or, maybe it does, if nothing on that layer is visible in the viewports on that sheet - but if you are tasked with preparing hundreds of files for turnover at the end of a project on which you did not work, including disciplines other than your own, you will likely not have time to carefully note what is visible in each viewport on each sheet and then reproduce that.) Using the BIND option of the BIND command may be the best course in this case.

I have been involved in such an effort lately, and in the course of that have come to a clearer understanding of how named objects are renamed when using the BIND option of the BIND command. I knew that the named objects in each external reference were renamed, using the external reference name as a prefix, with the vertical bar (|) delimiter being replaced with, typically, $0$. So, External01|A-Door would become External01$0$A-Door. A long time ago, when all this was new to me, I (erroneously) thought that the "0" in the delimiter was the layer name on which the external reference resided, as back then most, if not all, of our external references were placed on Layer 0. At some point, I did a "bind-bind" on an external reference on a different layer, and still got $0$ as the delimiter, and realized that the "0" was not the layer name on which the external reference was at the time of binding, but did not give it a whole lot of additional thought.

In my current effort, I am writing AutoLISP code to help automate certain processing tasks which involve being able to specify layer attributes for the root layer name, and have those applied to all variations of that root layer name, whether or not the layer has a prefix/delimiter from having been "bind-bound". I wanted my code to be able to identify the final delimiter in a layer name, so that the root name could be extracted. I made a very brief attempt to find something in the Help that described how the delimiter is determined, without any success. (It may be in there, and I just did not have enough patience to find it.) So I played around with some test files, with a very small number of layers, to figure out if the delimiter could ever be anything but $0$. As it turns out, it can, but, at least for the way we work, it will almost always be $0$. Your experience may vary, as your workflow may differ from ours.

When you bind-bind an external reference, AutoCAD® will create unique names for all of the named objects in the external reference, whether or not there is a named object of the same type and name in the host file. It does this as previously noted, by starting with a prefix that is the same as the external reference name (which may or may not be the same as the external file name), adding a delimiter consisting of a $ character followed by an integer followed by a $ character, and finally the root name of the named object. The first time you bind-bind an external reference of a given name, that integer will be 0. Should you later add an external reference of that same name (having renamed the bound block -OR- exploded the bound block and purged the definition), and then bind-bind that reference, AutoCAD will see that there already are named objects using the $0$ delimiter, and will increment the integer to "1" - $1$. Do all of that again, and the delimiter will be $2$. Do it eleven times, and the delimiter becomes $10$.

Armed with that knowledge, I was able to write code that would examine the layer names character-by-character, starting at the right end, and would collect the root name in a variable. Once a $ character was found, if it is preceded by one or more integers and then another $ character, that delimiter was saved and the routine then had both the root layer name and the last delimiter in the layer name, allowing the routine to be able to process things accordingly. (If you externally reference a file that has itself had an external reference bind-bound, and then bind-bind the reference, you can get named objects with multiple delimiters, such as External01$0$PreviouslyBound01$0$A-Door.)