Entering Values using the Project Base Point

A recent message asked how they can enter values into the Project Base Point (PBP) like we used to be able to do when the PBP had a clipped/not clipped status.

The answer is Specify Coordinates at Point (SCaP).

They wanted to enter 8,000,000/8,000,000 as their example. R2021 won't accept that value but R2019 would.

In the past, when we selected the PBP, entered coordinate values, it actually shifted the Survey Coordinate System (SCS) away from the Origin/PBP. It was easy to assume we moved the PBP because it is easy to overlook the information that displays above the selected PBP. It says PBP but right underneath (see image) it says Shared Site: and the coordinates it displays are relative to the SCS.

Entering values in the PBP directly (in the past) is same as using SCaP (now). The Survey Point will move to mark the 0,0 origin of the SCS after we enter our values. The PBP will still be at the Internal Origin (IO). The following image is 2019 and 2021 showing the same end result, just using a different tool.

Entering values directly into the PBP now will move it away from the IO, something it did not do in the past. This invokes a Local Coordinate System (LCS) that uses the PBP as its origin. Spot Coordinate/Elevation annotation can reference this LCS. This why Revit won't let us move the PBP too far (10 miles) from the IO.

I think Autodesk should change the PBP reference to the Shared Site since it is confusing. I think the PBP should show reference coordinates back to the Internal Origin. There is probably some room for disagreement though, which is why it probably still references the SCS.

This change seems to annoy people the most because we can't just enter values into the PBP directly and get the "old" result. We can enter values but not to alter the SCS, which is what really happens with the clipped PBP of old. The unclipped status of old is when the LCS is invoked.

The PBP only moves in an unclipped state now, thus no clip.

Internal Origin Follow Up

After I shared the earlier Dynamo graph I received an email from Aaron Rumple that did away with any package requirements. He wrote a python script and added it to my graph. It also eliminates the warning message that appears after running mine. The crux of that issue is the need to filter out view templates from the process because while view templates are applied to views under the hood they are also views...at least that's my layman's understanding.

Many thanks to Aaron, a real design software savant.

Download the new Dyn

As before, my graph allows you to include/exclude the internal origin, survey point and project base point. Just edit the settings of the Dyn before running it (see previous post).

Revit 2020.2 Turn Off Internal Origin - Dynamo Option

In a thread at RFO John Pierson (Parallax Team, and Dynamo guru) got the ball rolling with a video link that described overriding graphics in views. I picked up the ball and created the graph but missed an essential but tiny setting for one node to make it work (Lacing - Cross Product).

The Dynamo Graph looks like this (click to Download).

You can use Dynamo, with this graph, to turn off the Internal Origin, Survey Point, and Project Base Point in floor and ceiling plans, sections, elevations and 3D views. Change the code block from False to True and it will turn them all on instead.

Regarding Jean-Marc's comment: I think he was suggesting this instead.

Revit 2020.2 - Internal Origin

A quick post to mention this since I've already run into this issue with users several times. The latest update for Revit introduces a new icon to mark the location of the file's Internal Origin. This is what it looks like in the 3D view.

It's off in all views initially, in the stock templates. Reveal Elements will display it quickly in a view without having to use Visibility/Graphics to show it. It can't be selected, it's just visible to help understand where it is.

Edit: It seems existing projects that are opened in 2020.2 have this Internal Origin turned on in all views (many). That's a bug in my opinion. They should not be turning this on. Though, in my own testing it is not getting turned on with upgraded files. It seems to be existing 2020 files that get this turned after opening it with the 2020.2.

Project Base Point - You won't see the clip when you select it. Move it away from the internal origin and it is automatically behaving as if it isn't clipped. In other words, it isn't clipped anymore. We couldn't really move the project origin, only the Project Coordinate System could be adjusted to provide a local coordinate reference for the Spot Coordinate tool, for example.

The Survey Point remains much the same.

When dealing with linked files you'll find that the icons for each of these is also visible but halftone (gray) to differentiate from the host file's own icons. You can snap to the links icon's to help align the files, using the Move tool for example.

I'll have to return to the subject once we've gotten fully acquainted.

Edit: 11/24/2019

I traded a couple emails with Autodesk staff on this. My understanding (not a developer) is this is not merely something they overlooked. Consider when a 2020 file is opened in 2020.2 it is not going through an upgrade because the file format is compatible. This creates a scenario where they are not activating upgrade code to resolve the existing file's structure with a new version's structure.

Unfortunately this new subcategory gets enabled and its visible status is "on" at the outset. It's my understanding that "off" isn't an option...in this scenario...without also creating an upgrade scenario...which is conceptually a no-go...within a release year.

Upgraded files go through an upgrade process which imposes rules on that process...which includes a task that deliberately "turns off" this new subcategory. It's a quirk of the file open sequence/process.

I think they didn't expect it to be a significant issue. It doesn't print after all. It can negatively affect zooming behavior in many views though. User perceptions can't be ignored either. An unexpected "thing" encroaching on views is "bad"...similar to seeing a view's crop boundary when not intended.

To their credit, they asked if I agreed they should create a Dynamo solution to turn it off in all views. Naturally I encouraged them to DO IT! Hopefully we'll be able to say that such a solution exists soon.

Revit Coordinate Systems Video

A lengthy exchange at Autodesk's User Forums about this subject reminded me that I've meant to create a short video to describe how they relate to each other for quite awhile. This morning I saw our cutting boards drying next to the sink and realized they could serve as metaphorical coordinate system planes (Project and Survey) work in Revit. I am curious if readers find it helpful.



The original post at the forum dealt with a few projects that had been modelled very far from Revit's Internal Origin/Startup Location. I looked at one of the project files and found the Survey Point and Project Base Point had been moved very far away while unclipped. The modelling started there, really far far away. They started to experience some of the negative symptoms that can occur and started looking for solutions...thus the original post. The short answer is they needed to move their model closer to the origin. No other way around it.

Clipped or Un-clipped - That is the Question

The question asked: "Steve, should we leave our coordinate system icons clipped or un-clipped?"

My Answer: As we know, the Project Base Point (PBP) and Survey Point (SP) can be un-clipped. If they are untouched we'll find them clipped.

When these are clipped the symbols for each of these are attached to the coordinate systems they belong to. That means moving either while clipped will alter the coordinate system. If this is done unintentionally, or by someone who does not realize they have been adjusted intentionally already, the coordinate system(s) will be changed.

Therefore I'd say it is not unreasonable to leave these in their NOT clipped or un-clipped state at all times, especially after they have been adjusted intentionally to align models or survey data. If they are not clipped then accidental movement of these icons do not alter their related coordinate systems. It merely changes the symbol's position relative to their coordinate systems.

I regard these symbols as markers or annotation when they are not clipped. In this state they are harmless to our coordinate machinations. Clipped they pose a danger to our careful adjustments to align models and site information.

My opinion: Keep them Not clipped, un-clipped.

Survey Point Values after using Publish Coordinates

A RevitForum member remarked that it was confusing to see that the Survey Point shows 0,0,0 after using Publish Coordinates.

The image above shows the initial position, in a Building file, of the PBP and SP after using Publish Coordinates to pass the Shared Coordinate system information from a Site file to it. You can't see a building because they are quite far apart...which is why the icons do not change size when you zoom in/out.

When we open the Building model the Survey Point (SP) is marking its own origin, which is 0,0,0. When we examine the Project Base Point (PBP) we'll find coordinate values that indicate how far away it is from the SP. If we un-clip the SP we can choose to move it closer to the building and we'll see the coordinate values change to show how far the icon is moving away from its origin .

When we use Acquire Coordinates Revit moves the SP (when it is Pinned) to mark the location of the World Coordinate System origin (WCS assuming a DWG site source). When we use Publish Coordinates on the linked Building file it does the same thing but remember the SP is marking the WCS origin, which is 0,0,0 in the DWG...and for the SP of the building model too.

I hear and read the following a lot...

I then test it by removing the linked building model and re-link using shared coordinates and it works.

If you're tempted to do that, just don't do that on real projects since it opens the door to messing up the work we've just done. Just link the building model, re-position it and use Publish Coordinates. Then leave it alone; unless design changes require it to be moved again. A better test? Link the Site model into the Building model using By Shared Coordinates. That doesn't change anything you've done and you'll see they line up properly.

Placing a few spot coordinate annotations on this fine building design, after zooming in closer, looks like this. Also, the one closest to the PBP is assigned to PBP while the others are assigned to the SP.

Survey Point - Post 3 - Five Minutes with Shared Coordinates

I created a video that goes through the process I described in the previous two posts. It is set to a four and half minute song by Michael Lee Firkins called "The Window". If you've never heard his music I believe you owe it to yourself to check him out, very talented and unique sounding guitarist and song writer.

Survey Point
Survey Point - Post 2

Survey Point - Post 2

Yesterday I ended the post with a list of steps that I'd take to create a relationship between my building project file(s) and the Master Site file. I started another pair of projects that I'm calling Tiny House A and B (inspired by Sean's Tiny House project). I can start a project with or without site context. Revit's bias is making the project easy to document, forget about True North initially. It is trivial to resolve that in the Master Site file once it is ready, regardless if it is created before or after the tiny house models are started.

Here's how far I took the design of Tiny House A before I decided to work out its location on site.

I closed Tiny House A's project file. I opened up my Master Site file and linked Tiny House A using positioning: Auto - Origin to Origin. The choice for positioning at this stage really doesn't matter since I'm going to move the file to another part of the site anyway; have to pick something so I just let the default option reign. In the following image you can see Tiny House A is sitting at/near the Master Site's origin, marked by the Project Base Point icon.

Now it's time to move Tiny House A into position. I moved it and then aligned it with the East boundary. Then I was careful to put it at 8'-0" from that boundary. I then made sure the closest corner (wall) of the house to the North boundary was also at 8'-0". Being fussy about this isn't particularly important, I'm just being fussy.

Now I want to make sure the house is at an appropriate ground floor elevation. I created a section view so I could see the site's contours and the floor of the house. I can see here that the house is buried under a fair bit of the site.

I decided that raising the house to 22'-0" feels good. I used the Move tool, and typed 22 into the temporary listening dimension that appeared.

I think I'm ready to deal with Tiny House B now. It's really just another project file saved with a new name. I was too lazy to make another design. If this was a real project I wouldn't be able to get away with that. I decided that this house has to be no closer than 8'-0" to the North boundary but I've also made the North end of the house parallel to the boundary.

I learned while reading the development's covenant and zoning requirements that these houses can't be closer than 15'-0 to one another. I decided to put Tiny House B 18'-0" from A. I heard that A's owner is a drummer so those extra three feet might help keep B's sanity. I also decided that the ground floor elevation for B should be 20'-0", a little bit lower than A.

Now that I'm satisfied with the positions of Tiny House A and B I'm ready to use Publish Coordinates. This tool will PUSH the site orientation information to each house's project file. Revit will use this information to shift the house's Shared Coordinate system to align with the Shared Coordinate system of Master Site. In yesterday's post, the Master Site was manipulated to be in alignment with a linked DWG file's WCS (the World Coordinate System in AutoCAD to be precise) through the use of the Acquire Coordinates tool.

When you successfully select a linked file to Publish Coordinates the Location Weather and Site dialog appears. This give us an opportunity to provide a meaningful name for the location we're creating for that model. I clicked Rename... and typed Tiny House A Location 1.

It's significant to appreciate that I could now create a copy of Tiny House A in Master Site and place this copy in another location. I could then use Publish Coordinates on this copy which would allow me to use Duplicate... and use another name like Tiny House A Location 2. In the Tiny House A project file I can now choose between these two named locations and make one of them current. Revit will reorient everything to show the building correctly for this location, all without really changing anything  in the model. It's pretty clever and powerful; actually doing it is something I'll save for another post.

I used Publish Coordinates again but on Tiny House B and used the name Tiny House B Location 1 when the dialog appeared. I'm ready to return to work on my Tiny House A design. I clicked Save so I can close the Master Site project. The following dialog appears twice, once for Tiny House A and the second time for B. This is confirming that I want to commit the location and shared coordinate changes I made while using Publish Coordinates. I clicked Save each time (2x), the top option in the list.

It is necessary to make sure others are not working on the Tiny House A or B now. The Save will fail if someone is working on them. Just ask them to close the project for a minute. When worksharing is involved the same is true but it is a bit more forgiving. Either way, if an error message appears you need to ask others to stop working on these files briefly; they need to Save and close them. Once my Save is completed they can get back to work.

When I open Tiny House A I find that the Site plan is oriented to True North. I changed the Orientation parameter to True North earlier (noted in the image at the beginning). All plan views in the stock templates are assigned to Project North, including the Site view. Changing it meant that I'd see the results of using Publish Coordinates immediately, or at least as soon as I bother to open the Site view. The reality of this is that the project is NOT altered materially, no physical change to any geometry, it is just oriented correctly based on my actions in Master Site. This trivializes the task of re-positioning a building on site, if that becomes necessary.

Taking things a little further, each Level type has a Type Parameter called Elevation Base. It can be assigned to either Project Base Point or Survey Point. When I change this to Survey Point I find that the levels are reporting elevation values based on how much I raised Tiny House A in the Master Site file.

Now I've decided I want to be able to see Tiny House B here too, for context, but while working on Tiny House A. I linked Tiny House B into Tiny House A using positioning: Auto - By Shared Coordinates. This is possible because I used Publish Coordinates, from within Master Site, on both Tiny House A and B. Their shared understanding of their position in Master Site makes it possible to link either file into the other using Auto - By Shared Coordinates and they land in the correct spot relative to each other.

I can also link Master Site into either Tiny House A or B and use Auto - By Shared Coordinates too. They all understand their relationship to each other because of Publish Coordinates and the work I did in Master Site to put them into the proper context with each other. Here is Tiny House A, with Tiny House B linked in. I also created a Toposurface and Building Pads for each house in the Master Site file, then I returned to Tiny House A so I could link Master Site in using Auto - By Shared Coordinates as well.

A Few Notes

• Master Site is in CHARGE of positioning
• Only move models in Master Site
• Do not move linked models when viewed in other related project files
• Acquire Coordinates created the relationship between Survey and Master Site
• Publish Coordinates created the relationship between Master Site and Tiny House A and B
• Respect this order and it is easy to maintain
• It is technically possible to manipulate the relationship in either direction, DON'T.
• You must Resist the temptation!

Multi-Discipline Comments:

• Trades link the Tiny House A and B models into their projects using Auto - Origin to Origin, nothing else.
• Do NOT start work without a preliminary model of the Tiny House. If you do, be prepared to move your work into alignment manually.
• It is only necessary to use Acquire Coordinates on Tiny House A or B (whichever house you are designing for in your project file)
• It is only necessary to use Acquire Coordinates IF there IS an expectation that your data must align in 3rd party software like Navisworks
• The Tiny House projects will link your models using Auto - Origin to Origin too

Survey Point

In my view, it is no accident that the Survey Point (SP) is named using Survey. It's purpose or role in Revit is to permit us to relate our project to survey coordinate data, which is ordinarily provided by linking an external file. This image depicts a linked DWG site file whose origin is roughly 85 miles from the southwest property corner. The iron pipe at this corner has X/Y coordinates of exactly 450,000',450,000'.

It was imported using Positioning: Auto - Center to Center. This is what Autodesk recommends we do with files that are far from origin. Place the survey information close to the Project Base Point (origin) of the project. Then I used the Acquire Coordinates (AC) tool which was created to let us PULL this information in from the external (linked) source.

After using AC the Survey Point (clipped) marks (makes it easy to see) the actual origin of the source survey data's origin. It is why it usually disappears off into the distance, in stark contrast to where the project's origin is.

When the SP is un-clipped and dragged away from the origin, presumably closer to the project's site, it begins showing coordinate values that equal its offset from its origin, the origin is not altered/moved.

This is what the project looks like after I've finished adjusting the position of the unclipped Survey Point. At this point I only regard it as a marker that validates my belief that my Revit project is now aware of the same coordinate values as, and aligned (in sync with), the linked Survey file.

At this stage I save the file as my Master Site file. This file will act as the Control for site relationships with the site for any and all related building files I may use for this project.

Next (in a follow up post):

• Import a building file
• Position it (X/Y)
• Orient it (rotation)
• Raise it to the appropriate Ground Floor elevation
• Publish Coordinates
• Repeat for other buildings

Note:

• I'm intentionally NOT interested in the Project Base Point in this post
• I intentionally did NOT move or alter the Project Base Point
• I WON'T move or alter the Project Base Point in this file EVER.
• I WILL turn off the visibility of the Project Base Point.
• Shared Coordinates are NOT a Band-Aid, to fix poor communication/alignment

Importing CAD Files and By Shared Coordinates

When we link/import DWG files with survey data Revit often encounters file extents that are quite large. The developers have always encouraged us to use the Auto - Center to Center positioning option with those files. Revit will forcefully use that option when the extents of the file violate the current 20 mile tolerance it has.

I wish I could write that linking/importing survey files was very simple and error free. The reality couldn't be further from that. I recommend these steps to improve the odds for success:

• Import multiple Survey files individually (don't nest them as xref's)
• Purge everything you don't need, purge again
• Use Wblock if you can't get Zoom Extents to focus on just the relevant portion of the site
• Remove Named UCS (Revit only wants the World Coordinate System)
• Set UCS (User Coordinate System) to WCS and Plan to WCS
• If the survey isn't oriented to WCS, North is "up", have the civil engineer/surveyor change their file first
• Identify a specific location within the relevant part of the survey, put a marker, identify its coordinates, better still make those coordinates easy to use, even clean numbers.
• Make sure everything actually aligns correctly in AutoCAD first, no point setting it up in Revit if it doesn't work there
• Once you get a working first survey file, pass it back to the surveyor so they know what you need in the future

Once we've used Acquire Coordinates on our first survey file and verified the resulting coordinates are correct we can import the rest of the site related files. If Acquire Coordinates didn't work then we need revisit the items above, especially Named UCS. I find that Revit will acquire very large coordinates accurately IF the file is pristine.

In contrast I also like to use Specify Coordinates at Point (SCaP), using the marker I created earlier. Keeping in mind that doing so doesn't establish a shared coordinate relationship between the CAD file and the project. By relationship I mean that Revit records the identity of the linked file in the project when/if Acquire Coordinates is used to align the project with the linked file's WCS origin. SCaP does not.

Now regarding the title of this post, importing the rest of the files. Once shared coordinates are defined based on our first file we can import other site files using the positioning option: by Shared Coordinates. This assumes that each of the site related files are already aligned with each other using the same WCS origin. When we link a file this way a warning will appear while it is loading.

Revit is being precise, warning us that this project doesn't have a shared coordinate relationship with the incoming file. That's true, it is just another CAD file as far as this project is concerned. The only shared coordinate relationship that is established is between the first file and this project.

The last part of the warning is the significant part, The link's World coordinates will be aligned with this project's Shared coordinates". That means it will line up correctly because our project is aligned with the same WCS and both cad files already use the same WCS origin between themselves. Clicking Close accepts the warning and the link should land in the correct location. We can repeat this as many times as we have site related files to use.

When we save our project we may receive this warning. In this circumstance choose the bottom option Disable shared positioning...

We really don't want to create a named UCS in the CAD file the dialog references. It's linked and lined up correctly, its WCS is already correct, there is nothing to be gained by letting Revit store a named UCS in the file. This is what happens if you click Save instead, we end up with the named UCS in the image below.

I don't recall Revit bringing up this dialog in the past, unless I moved the link later, and I don't think it should be doing it in this circumstance. Fwiw, it doesn't in Revit 2015, at least not with the files I've been experimenting with for this post. It may be related to having a Named UCS. In some further testing I was able to link and save without generating the dialog. The inconsistency seems to consistently fall back on the condition of the DWG file though.

If we are careful to link each file and Disable the shared positioning Revit seems to think needs to be established all our linked file should line up very nicely. When they don't I find it necessary to revisit the list above. Skipping over them is very likely to bring on heartache later.

Relocate Project is Sleight of Hand

Try these steps:

• Create a new empty project
• Open the Site plan View
• Make sure the PBP (Project Base Point-circle) and the SP (Survey Point-triangle) are visible
• Use Relocate Project, "move" the PBP 1 meter to the left
• We'll find the SP is now 1 meter to the right, left behind marking where the origin was
• The SP identifies the origin of an alternate coordinate system, roughly equivalent to AutoCAD's WCS (World Coordinate System) origin, consider that using Acquire Coordinates aligns Revit with the WCS of the source DWG file.
• The previous steps are essentially the same as moving the SP (clipped) to the right 1 meter instead (use Undo and try it)
• Using Relocate Project you see the PBP move but its really the SP that's changed, it just doesn't look like it because the PBP is reporting a different 0,0 coordinate offset now (more on that below).

In a sense Revit just shifted the world over, underneath our building, and the origin never really changed. If we try the steps above and make sure we can see elevation symbols it becomes more apparent when they don't change their relationship to the PBP after using Relocate Project.

The PBP and SP start out at the same location in stock templates, but they are NOT marking the same information.

The Project Base Point always (when clipped) identifies where the project's origin is. The Survey Point identifies one alternate coordinate system's origin location, when it reports 0,0.

I believe it causes confusion when we examine the PBP coordinate values (when selected) because it displays values that are relative to where the SP defines the WCS origin, NOT the project origin. Since the project origin is never really changing it would be more accurate or consistent to continue displaying 0,0 and only begin showing different coordinates when it is moved un-clipped.

The following image shows a SP that has been moved by Acquire Coordinates to mark the WCS origin of a source survey DWG. The PBP now shows coordinates that match the offset from this alternate coordinate system's origin. To be fair it does say Shared Site: just above the values but it isn't as meaningful to most users as we'd hope.

The following image shows both PBP and SP moved while un-clipped. It is tempting to think of them as points when they are moved like this but they are really annotation referencing coordinates that are only meaningful when compared with where the origins they are referencing are, which I believe contributes to the confusion about what they display when selected.

General Comments and Advice

• The Project Base Point never displays coordinates that reference anything but the Shared Coordinate origin location.
• The Survey Point initially identifies an alternate coordinate origin but it can be un-clipped and moved to show coordinates that reference its origin location.
• The Project Base Point and Survey Point start by marking their own origins, at same location in stock templates but they are NOT the same coordinate systems.
• Don't use Relocate Project for X/Y axis project changes, it's really just establishing an offset relative to the Survey Point, not changing the project origin.
• Don't move the Project Base Point clipped
• Relocate Project can be useful in the Z axis when you need to show an arbitrary elevation value without placing the building at the actual elevations, see True Elevation and Position, it is still sleight of hand though, using Shared Coordinates to achieve the difference.
• Moving the PBP un-clipped can be used with the Spot Coordinate annotation. It can reference the Project Base Point location when it is desirable to mark locations, using the Spot Coordinate tool, that all reference where we've placed the un-clipped PBP.
  

Missing Survey Point

Traded a couple emails with Paul Aubin regarding a client's Survey Point that went missing. It turns out that it had been moved up quite high. I'd never tried to move either the Survey or Project Base Point symbols "up" before so it took me by surprise that it could be done.

Moral of the story, take care when you are selecting things and moving them. You could move your survey point unintentionally.